<?xml version="1.0" encoding="us-ascii"?>
<!--Generated by EDGARfilings PROfile 5.0.0.0 Broadridge-->
<link:linkbase xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xbrli="http://www.xbrl.org/2003/instance" xmlns:t1="http://xbrl.org/2005/xbrldt">
  <link:roleRef roleURI="http://usph.com/role/CommonStockDetails" xlink:type="simple" xlink:href="usph-20180930.xsd#CommonStockDetails" />
  <link:roleRef roleURI="http://usph.com/role/NotesPayableAndAmendedCreditAgreementSummaryOfAggregateAnnualPaymentsOfPrincipalRequiredToRevolvingCreditFacilityDetails" xlink:type="simple" xlink:href="usph-20180930.xsd#NotesPayableAndAmendedCreditAgreementSummaryOfAggregateAnnualPaymentsOfPrincipalRequiredToRevolvingCreditFacilityDetails" />
  <link:roleRef roleURI="http://usph.com/role/NotesPayableAndAmendedCreditAgreementDetails" xlink:type="simple" xlink:href="usph-20180930.xsd#NotesPayableAndAmendedCreditAgreementDetails" />
  <link:roleRef roleURI="http://usph.com/role/NotesPayableAndAmendedCreditAgreementSummaryOfNotesPayableAndCreditAgreementDetails" xlink:type="simple" xlink:href="usph-20180930.xsd#NotesPayableAndAmendedCreditAgreementSummaryOfNotesPayableAndCreditAgreementDetails" />
  <link:roleRef roleURI="http://usph.com/role/AccruedExpensesDetails" xlink:type="simple" xlink:href="usph-20180930.xsd#AccruedExpensesDetails" />
  <link:roleRef roleURI="http://usph.com/role/IntangibleAssetsNetAmortizationOfTradenameReferralRelationshipsAndNoncompetitionAgreementsDetails" xlink:type="simple" xlink:href="usph-20180930.xsd#IntangibleAssetsNetAmortizationOfTradenameReferralRelationshipsAndNoncompetitionAgreementsDetails" />
  <link:roleRef roleURI="http://usph.com/role/IntangibleAssetsNetAmortizationExpensesDetails" xlink:type="simple" xlink:href="usph-20180930.xsd#IntangibleAssetsNetAmortizationExpensesDetails" />
  <link:roleRef roleURI="http://usph.com/role/IntangibleAssetsNetIntangibleAssetsNetDetails" xlink:type="simple" xlink:href="usph-20180930.xsd#IntangibleAssetsNetIntangibleAssetsNetDetails" />
  <link:roleRef roleURI="http://usph.com/role/GoodwillDetails" xlink:type="simple" xlink:href="usph-20180930.xsd#GoodwillDetails" />
  <link:roleRef roleURI="http://usph.com/role/RedeemableNoncontrollingInterestsDetails" xlink:type="simple" xlink:href="usph-20180930.xsd#RedeemableNoncontrollingInterestsDetails" />
  <link:roleRef roleURI="http://usph.com/role/MandatorilyRedeemableNoncontrollingInterestsDetails" xlink:type="simple" xlink:href="usph-20180930.xsd#MandatorilyRedeemableNoncontrollingInterestsDetails" />
  <link:roleRef roleURI="http://usph.com/role/EarningsPerShareDetails" xlink:type="simple" xlink:href="usph-20180930.xsd#EarningsPerShareDetails" />
  <link:roleRef roleURI="http://usph.com/role/RevenueRecognitionDetails" xlink:type="simple" xlink:href="usph-20180930.xsd#RevenueRecognitionDetails" />
  <link:roleRef roleURI="http://usph.com/role/AcquisitionsOfBusinessesDetails" xlink:type="simple" xlink:href="usph-20180930.xsd#AcquisitionsOfBusinessesDetails" />
  <link:roleRef roleURI="http://usph.com/role/BasisOfPresentationAndSignificantAccountingPoliciesScheduleOfClinicAcquisitionDetails" xlink:type="simple" xlink:href="usph-20180930.xsd#BasisOfPresentationAndSignificantAccountingPoliciesScheduleOfClinicAcquisitionDetails" />
  <link:roleRef roleURI="http://usph.com/role/BasisOfPresentationAndSignificantAccountingPoliciesDetails" xlink:type="simple" xlink:href="usph-20180930.xsd#BasisOfPresentationAndSignificantAccountingPoliciesDetails" />
  <link:roleRef roleURI="http://usph.com/role/NotesPayableAndAmendedCreditAgreementTables" xlink:type="simple" xlink:href="usph-20180930.xsd#NotesPayableAndAmendedCreditAgreementTables" />
  <link:roleRef roleURI="http://usph.com/role/AccruedExpensesTables" xlink:type="simple" xlink:href="usph-20180930.xsd#AccruedExpensesTables" />
  <link:roleRef roleURI="http://usph.com/role/IntangibleAssetsNetTables" xlink:type="simple" xlink:href="usph-20180930.xsd#IntangibleAssetsNetTables" />
  <link:roleRef roleURI="http://usph.com/role/GoodwillTables" xlink:type="simple" xlink:href="usph-20180930.xsd#GoodwillTables" />
  <link:roleRef roleURI="http://usph.com/role/RedeemableNoncontrollingInterestsTables" xlink:type="simple" xlink:href="usph-20180930.xsd#RedeemableNoncontrollingInterestsTables" />
  <link:roleRef roleURI="http://usph.com/role/EarningsPerShareTables" xlink:type="simple" xlink:href="usph-20180930.xsd#EarningsPerShareTables" />
  <link:roleRef roleURI="http://usph.com/role/RevenueRecognitionTables" xlink:type="simple" xlink:href="usph-20180930.xsd#RevenueRecognitionTables" />
  <link:roleRef roleURI="http://usph.com/role/AcquisitionsOfBusinessesTables" xlink:type="simple" xlink:href="usph-20180930.xsd#AcquisitionsOfBusinessesTables" />
  <link:roleRef roleURI="http://usph.com/role/BasisOfPresentationAndSignificantAccountingPoliciesTables" xlink:type="simple" xlink:href="usph-20180930.xsd#BasisOfPresentationAndSignificantAccountingPoliciesTables" />
  <link:roleRef roleURI="http://usph.com/role/BasisOfPresentationAndSignificantAccountingPoliciesPolicies" xlink:type="simple" xlink:href="usph-20180930.xsd#BasisOfPresentationAndSignificantAccountingPoliciesPolicies" />
  <link:roleRef roleURI="http://usph.com/role/CommonStock" xlink:type="simple" xlink:href="usph-20180930.xsd#CommonStock" />
  <link:roleRef roleURI="http://usph.com/role/NotesPayableAndAmendedCreditAgreement" xlink:type="simple" xlink:href="usph-20180930.xsd#NotesPayableAndAmendedCreditAgreement" />
  <link:roleRef roleURI="http://usph.com/role/AccruedExpenses" xlink:type="simple" xlink:href="usph-20180930.xsd#AccruedExpenses" />
  <link:roleRef roleURI="http://usph.com/role/IntangibleAssetsNet" xlink:type="simple" xlink:href="usph-20180930.xsd#IntangibleAssetsNet" />
  <link:roleRef roleURI="http://usph.com/role/Goodwill" xlink:type="simple" xlink:href="usph-20180930.xsd#Goodwill" />
  <link:roleRef roleURI="http://usph.com/role/RedeemableNoncontrollingInterests" xlink:type="simple" xlink:href="usph-20180930.xsd#RedeemableNoncontrollingInterests" />
  <link:roleRef roleURI="http://usph.com/role/MandatorilyRedeemableNoncontrollingInterests" xlink:type="simple" xlink:href="usph-20180930.xsd#MandatorilyRedeemableNoncontrollingInterests" />
  <link:roleRef roleURI="http://usph.com/role/EarningsPerShare" xlink:type="simple" xlink:href="usph-20180930.xsd#EarningsPerShare" />
  <link:roleRef roleURI="http://usph.com/role/RevenueRecognition" xlink:type="simple" xlink:href="usph-20180930.xsd#RevenueRecognition" />
  <link:roleRef roleURI="http://usph.com/role/AcquisitionsOfBusinesses" xlink:type="simple" xlink:href="usph-20180930.xsd#AcquisitionsOfBusinesses" />
  <link:roleRef roleURI="http://usph.com/role/BasisOfPresentationAndSignificantAccountingPolicies" xlink:type="simple" xlink:href="usph-20180930.xsd#BasisOfPresentationAndSignificantAccountingPolicies" />
  <link:roleRef roleURI="http://usph.com/role/ConsolidatedStatementOfShareholdersEquityUnaudited" xlink:type="simple" xlink:href="usph-20180930.xsd#ConsolidatedStatementOfShareholdersEquityUnaudited" />
  <link:roleRef roleURI="http://usph.com/role/ConsolidatedStatementsOfCashFlowsUnaudited" xlink:type="simple" xlink:href="usph-20180930.xsd#ConsolidatedStatementsOfCashFlowsUnaudited" />
  <link:roleRef roleURI="http://usph.com/role/ConsolidatedStatementsOfNetIncomeUnaudited" xlink:type="simple" xlink:href="usph-20180930.xsd#ConsolidatedStatementsOfNetIncomeUnaudited" />
  <link:roleRef roleURI="http://usph.com/role/ConsolidatedBalanceSheetsUnauditedParenthetical" xlink:type="simple" xlink:href="usph-20180930.xsd#ConsolidatedBalanceSheetsUnauditedParenthetical" />
  <link:roleRef roleURI="http://usph.com/role/ConsolidatedBalanceSheetsUnaudited" xlink:type="simple" xlink:href="usph-20180930.xsd#ConsolidatedBalanceSheetsUnaudited" />
  <link:roleRef roleURI="http://usph.com/role/DocumentAndEntityInformation" xlink:type="simple" xlink:href="usph-20180930.xsd#DocumentAndEntityInformation" />
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/all" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all" />
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default" />
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain" />
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member" />
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension" />
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/DocumentAndEntityInformation" />
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/ConsolidatedBalanceSheetsUnaudited" />
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/ConsolidatedBalanceSheetsUnauditedParenthetical" />
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/ConsolidatedStatementsOfNetIncomeUnaudited">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementLineItems" xlink:label="StatementLineItems" xlink:title="StatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" xlink:label="RevenueFromContractWithCustomerExcludingAssessedTax" xlink:title="RevenueFromContractWithCustomerExcludingAssessedTax" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="StatementLineItems" xlink:to="RevenueFromContractWithCustomerExcludingAssessedTax" xlink:title="definition: StatementLineItems to RevenueFromContractWithCustomerExcludingAssessedTax" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementTable" xlink:label="StatementTable" xlink:title="StatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="StatementLineItems" xlink:to="StatementTable" xlink:title="definition: StatementLineItems to StatementTable" order="2.0" t1:closed="true" t1:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ProductOrServiceAxis" xlink:label="ProductOrServiceAxis" xlink:title="ProductOrServiceAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="StatementTable" xlink:to="ProductOrServiceAxis" xlink:title="definition: StatementTable to ProductOrServiceAxis" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ProductsAndServicesDomain" xlink:label="ProductsAndServicesDomain" xlink:title="ProductsAndServicesDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="ProductOrServiceAxis" xlink:to="ProductsAndServicesDomain" xlink:title="definition: ProductOrServiceAxis to ProductsAndServicesDomain" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ProductsAndServicesDomain" xlink:label="ProductsAndServicesDomain_2" xlink:title="ProductsAndServicesDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="ProductOrServiceAxis" xlink:to="ProductsAndServicesDomain_2" xlink:title="definition: ProductOrServiceAxis to ProductsAndServicesDomain_2" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_NetPatientRevenuesMember" xlink:label="NetPatientRevenuesMember" xlink:title="NetPatientRevenuesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ProductsAndServicesDomain" xlink:to="NetPatientRevenuesMember" xlink:title="definition: ProductsAndServicesDomain to NetPatientRevenuesMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_OtherRevenuesIncludingManagementContractRevenuesAndIndustrialInjuryPreventionServicesRevenuesMember" xlink:label="OtherRevenuesIncludingManagementContractRevenuesAndIndustrialInjuryPreventionServicesRevenuesMember" xlink:title="OtherRevenuesIncludingManagementContractRevenuesAndIndustrialInjuryPreventionServicesRevenuesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ProductsAndServicesDomain" xlink:to="OtherRevenuesIncludingManagementContractRevenuesAndIndustrialInjuryPreventionServicesRevenuesMember" xlink:title="definition: ProductsAndServicesDomain to OtherRevenuesIncludingManagementContractRevenuesAndIndustrialInjuryPreventionServicesRevenuesMember" order="2.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/ConsolidatedStatementsOfCashFlowsUnaudited" />
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/ConsolidatedStatementOfShareholdersEquityUnaudited">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementLineItems" xlink:label="StatementLineItems" xlink:title="StatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncreaseDecreaseInStockholdersEquityRollForward" xlink:label="IncreaseDecreaseInStockholdersEquityRollForward" xlink:title="IncreaseDecreaseInStockholdersEquityRollForward" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="StatementLineItems" xlink:to="IncreaseDecreaseInStockholdersEquityRollForward" xlink:title="definition: StatementLineItems to IncreaseDecreaseInStockholdersEquityRollForward" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest" xlink:label="StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest" xlink:title="StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="StatementLineItems" xlink:to="StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest" xlink:title="definition: StatementLineItems to StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SharesOutstanding" xlink:label="SharesOutstanding" xlink:title="SharesOutstanding" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="StatementLineItems" xlink:to="SharesOutstanding" xlink:title="definition: StatementLineItems to SharesOutstanding" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures" xlink:label="StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures" xlink:title="StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="StatementLineItems" xlink:to="StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures" xlink:title="definition: StatementLineItems to StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures" xlink:label="StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures" xlink:title="StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="StatementLineItems" xlink:to="StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures" xlink:title="definition: StatementLineItems to StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures" order="5.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_RevaluationOfRedeemableNonControllingInterestNetOfTax" xlink:label="RevaluationOfRedeemableNonControllingInterestNetOfTax" xlink:title="RevaluationOfRedeemableNonControllingInterestNetOfTax" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="StatementLineItems" xlink:to="RevaluationOfRedeemableNonControllingInterestNetOfTax" xlink:title="definition: StatementLineItems to RevaluationOfRedeemableNonControllingInterestNetOfTax" order="6.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue" xlink:label="AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue" xlink:title="AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="StatementLineItems" xlink:to="AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue" xlink:title="definition: StatementLineItems to AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue" order="7.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_TransferOfCompensationLiabilityForCertainStockIssuedPursuantToIncentivePlans" xlink:label="TransferOfCompensationLiabilityForCertainStockIssuedPursuantToIncentivePlans" xlink:title="TransferOfCompensationLiabilityForCertainStockIssuedPursuantToIncentivePlans" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="StatementLineItems" xlink:to="TransferOfCompensationLiabilityForCertainStockIssuedPursuantToIncentivePlans" xlink:title="definition: StatementLineItems to TransferOfCompensationLiabilityForCertainStockIssuedPursuantToIncentivePlans" order="8.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_MinorityInterestDecreaseFromRedemptions" xlink:label="MinorityInterestDecreaseFromRedemptions" xlink:title="MinorityInterestDecreaseFromRedemptions" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="StatementLineItems" xlink:to="MinorityInterestDecreaseFromRedemptions" xlink:title="definition: StatementLineItems to MinorityInterestDecreaseFromRedemptions" order="9.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DividendsCommonStockCash" xlink:label="DividendsCommonStockCash" xlink:title="DividendsCommonStockCash" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="StatementLineItems" xlink:to="DividendsCommonStockCash" xlink:title="definition: StatementLineItems to DividendsCommonStockCash" order="10.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders" xlink:label="MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders" xlink:title="MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="StatementLineItems" xlink:to="MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders" xlink:title="definition: StatementLineItems to MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders" order="11.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockholdersEquityOther" xlink:label="StockholdersEquityOther" xlink:title="StockholdersEquityOther" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="StatementLineItems" xlink:to="StockholdersEquityOther" xlink:title="definition: StatementLineItems to StockholdersEquityOther" order="12.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NetIncomeLossIncludingPortionAttributableToNonredeemableNoncontrollingInterest" xlink:label="NetIncomeLossIncludingPortionAttributableToNonredeemableNoncontrollingInterest" xlink:title="NetIncomeLossIncludingPortionAttributableToNonredeemableNoncontrollingInterest" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="StatementLineItems" xlink:to="NetIncomeLossIncludingPortionAttributableToNonredeemableNoncontrollingInterest" xlink:title="definition: StatementLineItems to NetIncomeLossIncludingPortionAttributableToNonredeemableNoncontrollingInterest" order="13.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementTable" xlink:label="StatementTable" xlink:title="StatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="StatementLineItems" xlink:to="StatementTable" xlink:title="definition: StatementLineItems to StatementTable" order="14.0" t1:closed="true" t1:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="StatementEquityComponentsAxis" xlink:title="StatementEquityComponentsAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="StatementTable" xlink:to="StatementEquityComponentsAxis" xlink:title="definition: StatementTable to StatementEquityComponentsAxis" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="EquityComponentDomain" xlink:title="EquityComponentDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="StatementEquityComponentsAxis" xlink:to="EquityComponentDomain" xlink:title="definition: StatementEquityComponentsAxis to EquityComponentDomain" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="EquityComponentDomain_2" xlink:title="EquityComponentDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="StatementEquityComponentsAxis" xlink:to="EquityComponentDomain_2" xlink:title="definition: StatementEquityComponentsAxis to EquityComponentDomain_2" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockMember" xlink:label="CommonStockMember" xlink:title="CommonStockMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EquityComponentDomain" xlink:to="CommonStockMember" xlink:title="definition: EquityComponentDomain to CommonStockMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AdditionalPaidInCapitalMember" xlink:label="AdditionalPaidInCapitalMember" xlink:title="AdditionalPaidInCapitalMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EquityComponentDomain" xlink:to="AdditionalPaidInCapitalMember" xlink:title="definition: EquityComponentDomain to AdditionalPaidInCapitalMember" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RetainedEarningsMember" xlink:label="RetainedEarningsMember" xlink:title="RetainedEarningsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EquityComponentDomain" xlink:to="RetainedEarningsMember" xlink:title="definition: EquityComponentDomain to RetainedEarningsMember" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TreasuryStockMember" xlink:label="TreasuryStockMember" xlink:title="TreasuryStockMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EquityComponentDomain" xlink:to="TreasuryStockMember" xlink:title="definition: EquityComponentDomain to TreasuryStockMember" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ParentMember" xlink:label="ParentMember" xlink:title="ParentMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EquityComponentDomain" xlink:to="ParentMember" xlink:title="definition: EquityComponentDomain to ParentMember" order="5.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NoncontrollingInterestMember" xlink:label="NoncontrollingInterestMember" xlink:title="NoncontrollingInterestMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EquityComponentDomain" xlink:to="NoncontrollingInterestMember" xlink:title="definition: EquityComponentDomain to NoncontrollingInterestMember" order="6.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/BasisOfPresentationAndSignificantAccountingPolicies" />
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/AcquisitionsOfBusinesses" />
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/RevenueRecognition" />
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/EarningsPerShare" />
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/MandatorilyRedeemableNoncontrollingInterests" />
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/RedeemableNoncontrollingInterests" />
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/Goodwill" />
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/IntangibleAssetsNet" />
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/AccruedExpenses" />
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/NotesPayableAndAmendedCreditAgreement" />
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/CommonStock" />
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/BasisOfPresentationAndSignificantAccountingPoliciesPolicies" />
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/BasisOfPresentationAndSignificantAccountingPoliciesTables" />
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/AcquisitionsOfBusinessesTables" />
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/RevenueRecognitionTables" />
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/EarningsPerShareTables" />
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/RedeemableNoncontrollingInterestsTables" />
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/GoodwillTables" />
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/IntangibleAssetsNetTables" />
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/AccruedExpensesTables" />
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/NotesPayableAndAmendedCreditAgreementTables" />
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/BasisOfPresentationAndSignificantAccountingPoliciesDetails">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredCompensationArrangementWithIndividualExcludingShareBasedPaymentsAndPostretirementBenefitsLineItems" xlink:label="DeferredCompensationArrangementWithIndividualExcludingShareBasedPaymentsAndPostretirementBenefitsLineItems" xlink:title="DeferredCompensationArrangementWithIndividualExcludingShareBasedPaymentsAndPostretirementBenefitsLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredCompensationArrangementsAbstract" xlink:label="DeferredCompensationArrangementsAbstract" xlink:title="DeferredCompensationArrangementsAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DeferredCompensationArrangementWithIndividualExcludingShareBasedPaymentsAndPostretirementBenefitsLineItems" xlink:to="DeferredCompensationArrangementsAbstract" xlink:title="definition: DeferredCompensationArrangementWithIndividualExcludingShareBasedPaymentsAndPostretirementBenefitsLineItems to DeferredCompensationArrangementsAbstract" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredCompensationArrangementWithIndividualRequisiteServicePeriod1" xlink:label="DeferredCompensationArrangementWithIndividualRequisiteServicePeriod1" xlink:title="DeferredCompensationArrangementWithIndividualRequisiteServicePeriod1" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DeferredCompensationArrangementWithIndividualExcludingShareBasedPaymentsAndPostretirementBenefitsLineItems" xlink:to="DeferredCompensationArrangementWithIndividualRequisiteServicePeriod1" xlink:title="definition: DeferredCompensationArrangementWithIndividualExcludingShareBasedPaymentsAndPostretirementBenefitsLineItems to DeferredCompensationArrangementWithIndividualRequisiteServicePeriod1" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfDeferredCompensationArrangementWithIndividualExcludingShareBasedPaymentsAndPostretirementBenefitsByTitleOfIndividualAndByTypeOfDeferredCompensationTable" xlink:label="ScheduleOfDeferredCompensationArrangementWithIndividualExcludingShareBasedPaymentsAndPostretirementBenefitsByTitleOfIndividualAndByTypeOfDeferredCompensationTable" xlink:title="ScheduleOfDeferredCompensationArrangementWithIndividualExcludingShareBasedPaymentsAndPostretirementBenefitsByTitleOfIndividualAndByTypeOfDeferredCompensationTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="DeferredCompensationArrangementWithIndividualExcludingShareBasedPaymentsAndPostretirementBenefitsLineItems" xlink:to="ScheduleOfDeferredCompensationArrangementWithIndividualExcludingShareBasedPaymentsAndPostretirementBenefitsByTitleOfIndividualAndByTypeOfDeferredCompensationTable" xlink:title="definition: DeferredCompensationArrangementWithIndividualExcludingShareBasedPaymentsAndPostretirementBenefitsLineItems to ScheduleOfDeferredCompensationArrangementWithIndividualExcludingShareBasedPaymentsAndPostretirementBenefitsByTitleOfIndividualAndByTypeOfDeferredCompensationTable" order="3.0" t1:closed="true" t1:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TitleOfIndividualAxis" xlink:label="TitleOfIndividualAxis" xlink:title="TitleOfIndividualAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfDeferredCompensationArrangementWithIndividualExcludingShareBasedPaymentsAndPostretirementBenefitsByTitleOfIndividualAndByTypeOfDeferredCompensationTable" xlink:to="TitleOfIndividualAxis" xlink:title="definition: ScheduleOfDeferredCompensationArrangementWithIndividualExcludingShareBasedPaymentsAndPostretirementBenefitsByTitleOfIndividualAndByTypeOfDeferredCompensationTable to TitleOfIndividualAxis" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TitleOfIndividualWithRelationshipToEntityDomain" xlink:label="TitleOfIndividualWithRelationshipToEntityDomain" xlink:title="TitleOfIndividualWithRelationshipToEntityDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="TitleOfIndividualAxis" xlink:to="TitleOfIndividualWithRelationshipToEntityDomain" xlink:title="definition: TitleOfIndividualAxis to TitleOfIndividualWithRelationshipToEntityDomain" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TitleOfIndividualWithRelationshipToEntityDomain" xlink:label="TitleOfIndividualWithRelationshipToEntityDomain_2" xlink:title="TitleOfIndividualWithRelationshipToEntityDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="TitleOfIndividualAxis" xlink:to="TitleOfIndividualWithRelationshipToEntityDomain_2" xlink:title="definition: TitleOfIndividualAxis to TitleOfIndividualWithRelationshipToEntityDomain_2" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_EmployeeMember" xlink:label="EmployeeMember" xlink:title="EmployeeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="TitleOfIndividualWithRelationshipToEntityDomain" xlink:to="EmployeeMember" xlink:title="definition: TitleOfIndividualWithRelationshipToEntityDomain to EmployeeMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DirectorMember" xlink:label="DirectorMember" xlink:title="DirectorMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="TitleOfIndividualWithRelationshipToEntityDomain" xlink:to="DirectorMember" xlink:title="definition: TitleOfIndividualWithRelationshipToEntityDomain to DirectorMember" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OfficerMember" xlink:label="OfficerMember" xlink:title="OfficerMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="TitleOfIndividualWithRelationshipToEntityDomain" xlink:to="OfficerMember" xlink:title="definition: TitleOfIndividualWithRelationshipToEntityDomain to OfficerMember" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_DepreciationAmortizationImpairmentLineItems" xlink:label="DepreciationAmortizationImpairmentLineItems" xlink:title="DepreciationAmortizationImpairmentLineItems" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_BasisOfPresentationAbstract" xlink:label="BasisOfPresentationAbstract" xlink:title="BasisOfPresentationAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DepreciationAmortizationImpairmentLineItems" xlink:to="BasisOfPresentationAbstract" xlink:title="definition: DepreciationAmortizationImpairmentLineItems to BasisOfPresentationAbstract" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_PercentageOfGeneralPartnershipInterestOwned" xlink:label="PercentageOfGeneralPartnershipInterestOwned" xlink:title="PercentageOfGeneralPartnershipInterestOwned" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DepreciationAmortizationImpairmentLineItems" xlink:to="PercentageOfGeneralPartnershipInterestOwned" xlink:title="definition: DepreciationAmortizationImpairmentLineItems to PercentageOfGeneralPartnershipInterestOwned" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_PercentageOfLimitedPartnershipInterestOwned" xlink:label="PercentageOfLimitedPartnershipInterestOwned" xlink:title="PercentageOfLimitedPartnershipInterestOwned" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DepreciationAmortizationImpairmentLineItems" xlink:to="PercentageOfLimitedPartnershipInterestOwned" xlink:title="definition: DepreciationAmortizationImpairmentLineItems to PercentageOfLimitedPartnershipInterestOwned" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired" xlink:label="BusinessAcquisitionPercentageOfVotingInterestsAcquired" xlink:title="BusinessAcquisitionPercentageOfVotingInterestsAcquired" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DepreciationAmortizationImpairmentLineItems" xlink:to="BusinessAcquisitionPercentageOfVotingInterestsAcquired" xlink:title="definition: DepreciationAmortizationImpairmentLineItems to BusinessAcquisitionPercentageOfVotingInterestsAcquired" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_NumberOfBusinessesMerged" xlink:label="NumberOfBusinessesMerged" xlink:title="NumberOfBusinessesMerged" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DepreciationAmortizationImpairmentLineItems" xlink:to="NumberOfBusinessesMerged" xlink:title="definition: DepreciationAmortizationImpairmentLineItems to NumberOfBusinessesMerged" order="5.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_PercentageOfCombinedBusinessInterestOwned" xlink:label="PercentageOfCombinedBusinessInterestOwned" xlink:title="PercentageOfCombinedBusinessInterestOwned" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DepreciationAmortizationImpairmentLineItems" xlink:to="PercentageOfCombinedBusinessInterestOwned" xlink:title="definition: DepreciationAmortizationImpairmentLineItems to PercentageOfCombinedBusinessInterestOwned" order="6.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NumberOfBusinessesAcquired" xlink:label="NumberOfBusinessesAcquired" xlink:title="NumberOfBusinessesAcquired" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DepreciationAmortizationImpairmentLineItems" xlink:to="NumberOfBusinessesAcquired" xlink:title="definition: DepreciationAmortizationImpairmentLineItems to NumberOfBusinessesAcquired" order="7.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_NumberOfClinicsConsolidatedWithExistingClinics" xlink:label="NumberOfClinicsConsolidatedWithExistingClinics" xlink:title="NumberOfClinicsConsolidatedWithExistingClinics" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DepreciationAmortizationImpairmentLineItems" xlink:to="NumberOfClinicsConsolidatedWithExistingClinics" xlink:title="definition: DepreciationAmortizationImpairmentLineItems to NumberOfClinicsConsolidatedWithExistingClinics" order="8.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_NumberOfClinicsOperatesAsASatelliteClinicWithExistingPartnerships" xlink:label="NumberOfClinicsOperatesAsASatelliteClinicWithExistingPartnerships" xlink:title="NumberOfClinicsOperatesAsASatelliteClinicWithExistingPartnerships" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DepreciationAmortizationImpairmentLineItems" xlink:to="NumberOfClinicsOperatesAsASatelliteClinicWithExistingPartnerships" xlink:title="definition: DepreciationAmortizationImpairmentLineItems to NumberOfClinicsOperatesAsASatelliteClinicWithExistingPartnerships" order="9.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_NumberOfClinicsOperated" xlink:label="NumberOfClinicsOperated" xlink:title="NumberOfClinicsOperated" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DepreciationAmortizationImpairmentLineItems" xlink:to="NumberOfClinicsOperated" xlink:title="definition: DepreciationAmortizationImpairmentLineItems to NumberOfClinicsOperated" order="10.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NumberOfStatesInWhichEntityOperates" xlink:label="NumberOfStatesInWhichEntityOperates" xlink:title="NumberOfStatesInWhichEntityOperates" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DepreciationAmortizationImpairmentLineItems" xlink:to="NumberOfStatesInWhichEntityOperates" xlink:title="definition: DepreciationAmortizationImpairmentLineItems to NumberOfStatesInWhichEntityOperates" order="11.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_NumberOfThirdPartyFacilities" xlink:label="NumberOfThirdPartyFacilities" xlink:title="NumberOfThirdPartyFacilities" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DepreciationAmortizationImpairmentLineItems" xlink:to="NumberOfThirdPartyFacilities" xlink:title="definition: DepreciationAmortizationImpairmentLineItems to NumberOfThirdPartyFacilities" order="12.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SharesSubjectToMandatoryRedemptionSettlementTermsAmountNoncurrent" xlink:label="SharesSubjectToMandatoryRedemptionSettlementTermsAmountNoncurrent" xlink:title="SharesSubjectToMandatoryRedemptionSettlementTermsAmountNoncurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DepreciationAmortizationImpairmentLineItems" xlink:to="SharesSubjectToMandatoryRedemptionSettlementTermsAmountNoncurrent" xlink:title="definition: DepreciationAmortizationImpairmentLineItems to SharesSubjectToMandatoryRedemptionSettlementTermsAmountNoncurrent" order="13.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PropertyPlantAndEquipmentUsefulLife" xlink:label="PropertyPlantAndEquipmentUsefulLife" xlink:title="PropertyPlantAndEquipmentUsefulLife" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DepreciationAmortizationImpairmentLineItems" xlink:to="PropertyPlantAndEquipmentUsefulLife" xlink:title="definition: DepreciationAmortizationImpairmentLineItems to PropertyPlantAndEquipmentUsefulLife" order="14.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_NumberOfRegions" xlink:label="NumberOfRegions" xlink:title="NumberOfRegions" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DepreciationAmortizationImpairmentLineItems" xlink:to="NumberOfRegions" xlink:title="definition: DepreciationAmortizationImpairmentLineItems to NumberOfRegions" order="15.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_RedeemableNonControllingInterestRedemptionRightsCommencementPeriod" xlink:label="RedeemableNonControllingInterestRedemptionRightsCommencementPeriod" xlink:title="RedeemableNonControllingInterestRedemptionRightsCommencementPeriod" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DepreciationAmortizationImpairmentLineItems" xlink:to="RedeemableNonControllingInterestRedemptionRightsCommencementPeriod" xlink:title="definition: DepreciationAmortizationImpairmentLineItems to RedeemableNonControllingInterestRedemptionRightsCommencementPeriod" order="16.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate" xlink:label="EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate" xlink:title="EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DepreciationAmortizationImpairmentLineItems" xlink:to="EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate" xlink:title="definition: DepreciationAmortizationImpairmentLineItems to EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate" order="17.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense" xlink:label="UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense" xlink:title="UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DepreciationAmortizationImpairmentLineItems" xlink:to="UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense" xlink:title="definition: DepreciationAmortizationImpairmentLineItems to UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense" order="18.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued" xlink:label="UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued" xlink:title="UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DepreciationAmortizationImpairmentLineItems" xlink:to="UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued" xlink:title="definition: DepreciationAmortizationImpairmentLineItems to UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued" order="19.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InterestExpenseOnPrepetitionLiabilitiesRecognizedInStatementOfOperations" xlink:label="InterestExpenseOnPrepetitionLiabilitiesRecognizedInStatementOfOperations" xlink:title="InterestExpenseOnPrepetitionLiabilitiesRecognizedInStatementOfOperations" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DepreciationAmortizationImpairmentLineItems" xlink:to="InterestExpenseOnPrepetitionLiabilitiesRecognizedInStatementOfOperations" xlink:title="definition: DepreciationAmortizationImpairmentLineItems to InterestExpenseOnPrepetitionLiabilitiesRecognizedInStatementOfOperations" order="20.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_DepreciationAmortizationImpairmentTable" xlink:label="DepreciationAmortizationImpairmentTable" xlink:title="DepreciationAmortizationImpairmentTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="DepreciationAmortizationImpairmentLineItems" xlink:to="DepreciationAmortizationImpairmentTable" xlink:title="definition: DepreciationAmortizationImpairmentLineItems to DepreciationAmortizationImpairmentTable" order="21.0" t1:closed="true" t1:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeAxis" xlink:label="RangeAxis" xlink:title="RangeAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="DepreciationAmortizationImpairmentTable" xlink:to="RangeAxis" xlink:title="definition: DepreciationAmortizationImpairmentTable to RangeAxis" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeMember" xlink:label="RangeMember" xlink:title="RangeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="RangeAxis" xlink:to="RangeMember" xlink:title="definition: RangeAxis to RangeMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeMember" xlink:label="RangeMember_2" xlink:title="RangeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="RangeAxis" xlink:to="RangeMember_2" xlink:title="definition: RangeAxis to RangeMember_2" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_MinimumMember" xlink:label="MinimumMember" xlink:title="MinimumMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RangeMember" xlink:to="MinimumMember" xlink:title="definition: RangeMember to MinimumMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_MaximumMember" xlink:label="MaximumMember" xlink:title="MaximumMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RangeMember" xlink:to="MaximumMember" xlink:title="definition: RangeMember to MaximumMember" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessAcquisitionAxis" xlink:label="BusinessAcquisitionAxis" xlink:title="BusinessAcquisitionAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="DepreciationAmortizationImpairmentTable" xlink:to="BusinessAcquisitionAxis" xlink:title="definition: DepreciationAmortizationImpairmentTable to BusinessAcquisitionAxis" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="BusinessAcquisitionAcquireeDomain" xlink:title="BusinessAcquisitionAcquireeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="BusinessAcquisitionAxis" xlink:to="BusinessAcquisitionAcquireeDomain" xlink:title="definition: BusinessAcquisitionAxis to BusinessAcquisitionAcquireeDomain" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="BusinessAcquisitionAcquireeDomain_2" xlink:title="BusinessAcquisitionAcquireeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="BusinessAcquisitionAxis" xlink:to="BusinessAcquisitionAcquireeDomain_2" xlink:title="definition: BusinessAcquisitionAxis to BusinessAcquisitionAcquireeDomain_2" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_MarchTwoThousandSeventeenAcquisitionMember" xlink:label="MarchTwoThousandSeventeenAcquisitionMember" xlink:title="MarchTwoThousandSeventeenAcquisitionMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionAcquireeDomain" xlink:to="MarchTwoThousandSeventeenAcquisitionMember" xlink:title="definition: BusinessAcquisitionAcquireeDomain to MarchTwoThousandSeventeenAcquisitionMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_LeadingProviderOfIndustrialInjuryPreventionMember" xlink:label="LeadingProviderOfIndustrialInjuryPreventionMember" xlink:title="LeadingProviderOfIndustrialInjuryPreventionMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionAcquireeDomain" xlink:to="LeadingProviderOfIndustrialInjuryPreventionMember" xlink:title="definition: BusinessAcquisitionAcquireeDomain to LeadingProviderOfIndustrialInjuryPreventionMember" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis" xlink:label="PropertyPlantAndEquipmentByTypeAxis" xlink:title="PropertyPlantAndEquipmentByTypeAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="DepreciationAmortizationImpairmentTable" xlink:to="PropertyPlantAndEquipmentByTypeAxis" xlink:title="definition: DepreciationAmortizationImpairmentTable to PropertyPlantAndEquipmentByTypeAxis" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:label="PropertyPlantAndEquipmentTypeDomain" xlink:title="PropertyPlantAndEquipmentTypeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="PropertyPlantAndEquipmentByTypeAxis" xlink:to="PropertyPlantAndEquipmentTypeDomain" xlink:title="definition: PropertyPlantAndEquipmentByTypeAxis to PropertyPlantAndEquipmentTypeDomain" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:label="PropertyPlantAndEquipmentTypeDomain_2" xlink:title="PropertyPlantAndEquipmentTypeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="PropertyPlantAndEquipmentByTypeAxis" xlink:to="PropertyPlantAndEquipmentTypeDomain_2" xlink:title="definition: PropertyPlantAndEquipmentByTypeAxis to PropertyPlantAndEquipmentTypeDomain_2" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FurnitureAndFixturesMember" xlink:label="FurnitureAndFixturesMember" xlink:title="FurnitureAndFixturesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="PropertyPlantAndEquipmentTypeDomain" xlink:to="FurnitureAndFixturesMember" xlink:title="definition: PropertyPlantAndEquipmentTypeDomain to FurnitureAndFixturesMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ComputerSoftwareIntangibleAssetMember" xlink:label="ComputerSoftwareIntangibleAssetMember" xlink:title="ComputerSoftwareIntangibleAssetMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="PropertyPlantAndEquipmentTypeDomain" xlink:to="ComputerSoftwareIntangibleAssetMember" xlink:title="definition: PropertyPlantAndEquipmentTypeDomain to ComputerSoftwareIntangibleAssetMember" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LeaseholdImprovementsMember" xlink:label="LeaseholdImprovementsMember" xlink:title="LeaseholdImprovementsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="PropertyPlantAndEquipmentTypeDomain" xlink:to="LeaseholdImprovementsMember" xlink:title="definition: PropertyPlantAndEquipmentTypeDomain to LeaseholdImprovementsMember" order="3.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/BasisOfPresentationAndSignificantAccountingPoliciesScheduleOfClinicAcquisitionDetails">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessAcquisitionLineItems" xlink:label="BusinessAcquisitionLineItems" xlink:title="BusinessAcquisitionLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessCombinationDescriptionAbstract" xlink:label="BusinessCombinationDescriptionAbstract" xlink:title="BusinessCombinationDescriptionAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessCombinationDescriptionAbstract" xlink:title="definition: BusinessAcquisitionLineItems to BusinessCombinationDescriptionAbstract" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessAcquisitionDateOfAcquisitionAgreement1" xlink:label="BusinessAcquisitionDateOfAcquisitionAgreement1" xlink:title="BusinessAcquisitionDateOfAcquisitionAgreement1" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessAcquisitionDateOfAcquisitionAgreement1" xlink:title="definition: BusinessAcquisitionLineItems to BusinessAcquisitionDateOfAcquisitionAgreement1" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired" xlink:label="BusinessAcquisitionPercentageOfVotingInterestsAcquired" xlink:title="BusinessAcquisitionPercentageOfVotingInterestsAcquired" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessAcquisitionPercentageOfVotingInterestsAcquired" xlink:title="definition: BusinessAcquisitionLineItems to BusinessAcquisitionPercentageOfVotingInterestsAcquired" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NumberOfBusinessesAcquired" xlink:label="NumberOfBusinessesAcquired" xlink:title="NumberOfBusinessesAcquired" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="NumberOfBusinessesAcquired" xlink:title="definition: BusinessAcquisitionLineItems to NumberOfBusinessesAcquired" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:label="ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:title="ScheduleOfBusinessAcquisitionsByAcquisitionTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="BusinessAcquisitionLineItems" xlink:to="ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:title="definition: BusinessAcquisitionLineItems to ScheduleOfBusinessAcquisitionsByAcquisitionTable" order="5.0" t1:closed="true" t1:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessAcquisitionAxis" xlink:label="BusinessAcquisitionAxis" xlink:title="BusinessAcquisitionAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:to="BusinessAcquisitionAxis" xlink:title="definition: ScheduleOfBusinessAcquisitionsByAcquisitionTable to BusinessAcquisitionAxis" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="BusinessAcquisitionAcquireeDomain" xlink:title="BusinessAcquisitionAcquireeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="BusinessAcquisitionAxis" xlink:to="BusinessAcquisitionAcquireeDomain" xlink:title="definition: BusinessAcquisitionAxis to BusinessAcquisitionAcquireeDomain" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="BusinessAcquisitionAcquireeDomain_2" xlink:title="BusinessAcquisitionAcquireeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="BusinessAcquisitionAxis" xlink:to="BusinessAcquisitionAcquireeDomain_2" xlink:title="definition: BusinessAcquisitionAxis to BusinessAcquisitionAcquireeDomain_2" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_JanuaryTwoThousandSeventeenAcquisitionMember" xlink:label="JanuaryTwoThousandSeventeenAcquisitionMember" xlink:title="JanuaryTwoThousandSeventeenAcquisitionMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionAcquireeDomain" xlink:to="JanuaryTwoThousandSeventeenAcquisitionMember" xlink:title="definition: BusinessAcquisitionAcquireeDomain to JanuaryTwoThousandSeventeenAcquisitionMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_MayTwoThousandSeventeenAcquisitionMember" xlink:label="MayTwoThousandSeventeenAcquisitionMember" xlink:title="MayTwoThousandSeventeenAcquisitionMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionAcquireeDomain" xlink:to="MayTwoThousandSeventeenAcquisitionMember" xlink:title="definition: BusinessAcquisitionAcquireeDomain to MayTwoThousandSeventeenAcquisitionMember" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_JuneTwoThousandSeventeenAcquisitionMember" xlink:label="JuneTwoThousandSeventeenAcquisitionMember" xlink:title="JuneTwoThousandSeventeenAcquisitionMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionAcquireeDomain" xlink:to="JuneTwoThousandSeventeenAcquisitionMember" xlink:title="definition: BusinessAcquisitionAcquireeDomain to JuneTwoThousandSeventeenAcquisitionMember" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_OctoberTwoThousandSeventeenAcquisitionMember" xlink:label="OctoberTwoThousandSeventeenAcquisitionMember" xlink:title="OctoberTwoThousandSeventeenAcquisitionMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionAcquireeDomain" xlink:to="OctoberTwoThousandSeventeenAcquisitionMember" xlink:title="definition: BusinessAcquisitionAcquireeDomain to OctoberTwoThousandSeventeenAcquisitionMember" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_August2018AcquisitionMember" xlink:label="August2018AcquisitionMember" xlink:title="August2018AcquisitionMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionAcquireeDomain" xlink:to="August2018AcquisitionMember" xlink:title="definition: BusinessAcquisitionAcquireeDomain to August2018AcquisitionMember" order="5.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/AcquisitionsOfBusinessesDetails">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessAcquisitionLineItems" xlink:label="BusinessAcquisitionLineItems" xlink:title="BusinessAcquisitionLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessCombinationDescriptionAbstract" xlink:label="BusinessCombinationDescriptionAbstract" xlink:title="BusinessCombinationDescriptionAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessCombinationDescriptionAbstract" xlink:title="definition: BusinessAcquisitionLineItems to BusinessCombinationDescriptionAbstract" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NumberOfBusinessesAcquired" xlink:label="NumberOfBusinessesAcquired" xlink:title="NumberOfBusinessesAcquired" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="NumberOfBusinessesAcquired" xlink:title="definition: BusinessAcquisitionLineItems to NumberOfBusinessesAcquired" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_NumberOfManagementContracts" xlink:label="NumberOfManagementContracts" xlink:title="NumberOfManagementContracts" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="NumberOfManagementContracts" xlink:title="definition: BusinessAcquisitionLineItems to NumberOfManagementContracts" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_NumberOfClinicsConsolidatedWithExistingClinics" xlink:label="NumberOfClinicsConsolidatedWithExistingClinics" xlink:title="NumberOfClinicsConsolidatedWithExistingClinics" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="NumberOfClinicsConsolidatedWithExistingClinics" xlink:title="definition: BusinessAcquisitionLineItems to NumberOfClinicsConsolidatedWithExistingClinics" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_NumberOfClinicsOperatesAsASatelliteClinicWithExistingPartnerships" xlink:label="NumberOfClinicsOperatesAsASatelliteClinicWithExistingPartnerships" xlink:title="NumberOfClinicsOperatesAsASatelliteClinicWithExistingPartnerships" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="NumberOfClinicsOperatesAsASatelliteClinicWithExistingPartnerships" xlink:title="definition: BusinessAcquisitionLineItems to NumberOfClinicsOperatesAsASatelliteClinicWithExistingPartnerships" order="5.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired" xlink:label="BusinessAcquisitionPercentageOfVotingInterestsAcquired" xlink:title="BusinessAcquisitionPercentageOfVotingInterestsAcquired" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessAcquisitionPercentageOfVotingInterestsAcquired" xlink:title="definition: BusinessAcquisitionLineItems to BusinessAcquisitionPercentageOfVotingInterestsAcquired" order="6.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PaymentsToAcquireBusinessesGross" xlink:label="PaymentsToAcquireBusinessesGross" xlink:title="PaymentsToAcquireBusinessesGross" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="PaymentsToAcquireBusinessesGross" xlink:title="definition: BusinessAcquisitionLineItems to PaymentsToAcquireBusinessesGross" order="7.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_BusinessAcquisitionCostOfAcquiredEntityDebtIssued" xlink:label="BusinessAcquisitionCostOfAcquiredEntityDebtIssued" xlink:title="BusinessAcquisitionCostOfAcquiredEntityDebtIssued" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessAcquisitionCostOfAcquiredEntityDebtIssued" xlink:title="definition: BusinessAcquisitionLineItems to BusinessAcquisitionCostOfAcquiredEntityDebtIssued" order="8.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_NumberOfBusinessesMerged" xlink:label="NumberOfBusinessesMerged" xlink:title="NumberOfBusinessesMerged" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="NumberOfBusinessesMerged" xlink:title="definition: BusinessAcquisitionLineItems to NumberOfBusinessesMerged" order="9.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_PercentageOfCombinedBusinessInterestOwned" xlink:label="PercentageOfCombinedBusinessInterestOwned" xlink:title="PercentageOfCombinedBusinessInterestOwned" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="PercentageOfCombinedBusinessInterestOwned" xlink:title="definition: BusinessAcquisitionLineItems to PercentageOfCombinedBusinessInterestOwned" order="10.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_BusinessAcquisitionNumberOfInstallmentsToPaymentOfPurchaseConsideration" xlink:label="BusinessAcquisitionNumberOfInstallmentsToPaymentOfPurchaseConsideration" xlink:title="BusinessAcquisitionNumberOfInstallmentsToPaymentOfPurchaseConsideration" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessAcquisitionNumberOfInstallmentsToPaymentOfPurchaseConsideration" xlink:title="definition: BusinessAcquisitionLineItems to BusinessAcquisitionNumberOfInstallmentsToPaymentOfPurchaseConsideration" order="11.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_BusinessAcquisitionPrincipalInstallmentsPayableAtCostOfAcquiredByEntityAtAccruedInterest" xlink:label="BusinessAcquisitionPrincipalInstallmentsPayableAtCostOfAcquiredByEntityAtAccruedInterest" xlink:title="BusinessAcquisitionPrincipalInstallmentsPayableAtCostOfAcquiredByEntityAtAccruedInterest" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessAcquisitionPrincipalInstallmentsPayableAtCostOfAcquiredByEntityAtAccruedInterest" xlink:title="definition: BusinessAcquisitionLineItems to BusinessAcquisitionPrincipalInstallmentsPayableAtCostOfAcquiredByEntityAtAccruedInterest" order="12.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_BusinessCombinationAcquiredFiniteLivedIntangibleAssetUsefulLife" xlink:label="BusinessCombinationAcquiredFiniteLivedIntangibleAssetUsefulLife" xlink:title="BusinessCombinationAcquiredFiniteLivedIntangibleAssetUsefulLife" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessCombinationAcquiredFiniteLivedIntangibleAssetUsefulLife" xlink:title="definition: BusinessAcquisitionLineItems to BusinessCombinationAcquiredFiniteLivedIntangibleAssetUsefulLife" order="13.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:label="ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:title="ScheduleOfBusinessAcquisitionsByAcquisitionTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="BusinessAcquisitionLineItems" xlink:to="ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:title="definition: BusinessAcquisitionLineItems to ScheduleOfBusinessAcquisitionsByAcquisitionTable" order="14.0" t1:closed="true" t1:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessAcquisitionAxis" xlink:label="BusinessAcquisitionAxis" xlink:title="BusinessAcquisitionAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:to="BusinessAcquisitionAxis" xlink:title="definition: ScheduleOfBusinessAcquisitionsByAcquisitionTable to BusinessAcquisitionAxis" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="BusinessAcquisitionAcquireeDomain" xlink:title="BusinessAcquisitionAcquireeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="BusinessAcquisitionAxis" xlink:to="BusinessAcquisitionAcquireeDomain" xlink:title="definition: BusinessAcquisitionAxis to BusinessAcquisitionAcquireeDomain" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="BusinessAcquisitionAcquireeDomain_2" xlink:title="BusinessAcquisitionAcquireeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="BusinessAcquisitionAxis" xlink:to="BusinessAcquisitionAcquireeDomain_2" xlink:title="definition: BusinessAcquisitionAxis to BusinessAcquisitionAcquireeDomain_2" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_AcquisitionOfTwoClinicPracticesMember" xlink:label="AcquisitionOfTwoClinicPracticesMember" xlink:title="AcquisitionOfTwoClinicPracticesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionAcquireeDomain" xlink:to="AcquisitionOfTwoClinicPracticesMember" xlink:title="definition: BusinessAcquisitionAcquireeDomain to AcquisitionOfTwoClinicPracticesMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_PhysicalTherapyPracticeMember" xlink:label="PhysicalTherapyPracticeMember" xlink:title="PhysicalTherapyPracticeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionAcquireeDomain" xlink:to="PhysicalTherapyPracticeMember" xlink:title="definition: BusinessAcquisitionAcquireeDomain to PhysicalTherapyPracticeMember" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_LeadingProviderOfIndustrialInjuryPreventionMember" xlink:label="LeadingProviderOfIndustrialInjuryPreventionMember" xlink:title="LeadingProviderOfIndustrialInjuryPreventionMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionAcquireeDomain" xlink:to="LeadingProviderOfIndustrialInjuryPreventionMember" xlink:title="definition: BusinessAcquisitionAcquireeDomain to LeadingProviderOfIndustrialInjuryPreventionMember" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_AcquisitionOfSeventeenClinicPracticesMember" xlink:label="AcquisitionOfSeventeenClinicPracticesMember" xlink:title="AcquisitionOfSeventeenClinicPracticesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionAcquireeDomain" xlink:to="AcquisitionOfSeventeenClinicPracticesMember" xlink:title="definition: BusinessAcquisitionAcquireeDomain to AcquisitionOfSeventeenClinicPracticesMember" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_AcquisitionOfFourClinicPracticesMember" xlink:label="AcquisitionOfFourClinicPracticesMember" xlink:title="AcquisitionOfFourClinicPracticesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionAcquireeDomain" xlink:to="AcquisitionOfFourClinicPracticesMember" xlink:title="definition: BusinessAcquisitionAcquireeDomain to AcquisitionOfFourClinicPracticesMember" order="5.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_AcquisitionOfNineClinicPracticesMember" xlink:label="AcquisitionOfNineClinicPracticesMember" xlink:title="AcquisitionOfNineClinicPracticesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionAcquireeDomain" xlink:to="AcquisitionOfNineClinicPracticesMember" xlink:title="definition: BusinessAcquisitionAcquireeDomain to AcquisitionOfNineClinicPracticesMember" order="6.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:label="FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:title="FiniteLivedIntangibleAssetsByMajorClassAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:to="FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:title="definition: ScheduleOfBusinessAcquisitionsByAcquisitionTable to FiniteLivedIntangibleAssetsByMajorClassAxis" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:title="FiniteLivedIntangibleAssetsMajorClassNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:to="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:title="definition: FiniteLivedIntangibleAssetsByMajorClassAxis to FiniteLivedIntangibleAssetsMajorClassNameDomain" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="FiniteLivedIntangibleAssetsMajorClassNameDomain_2" xlink:title="FiniteLivedIntangibleAssetsMajorClassNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:to="FiniteLivedIntangibleAssetsMajorClassNameDomain_2" xlink:title="definition: FiniteLivedIntangibleAssetsByMajorClassAxis to FiniteLivedIntangibleAssetsMajorClassNameDomain_2" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_ReferralRelationshipMember" xlink:label="ReferralRelationshipMember" xlink:title="ReferralRelationshipMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="ReferralRelationshipMember" xlink:title="definition: FiniteLivedIntangibleAssetsMajorClassNameDomain to ReferralRelationshipMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NoncompeteAgreementsMember" xlink:label="NoncompeteAgreementsMember" xlink:title="NoncompeteAgreementsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="NoncompeteAgreementsMember" xlink:title="definition: FiniteLivedIntangibleAssetsMajorClassNameDomain to NoncompeteAgreementsMember" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementScenarioAxis" xlink:label="StatementScenarioAxis" xlink:title="StatementScenarioAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:to="StatementScenarioAxis" xlink:title="definition: ScheduleOfBusinessAcquisitionsByAcquisitionTable to StatementScenarioAxis" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScenarioUnspecifiedDomain" xlink:label="ScenarioUnspecifiedDomain" xlink:title="ScenarioUnspecifiedDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="StatementScenarioAxis" xlink:to="ScenarioUnspecifiedDomain" xlink:title="definition: StatementScenarioAxis to ScenarioUnspecifiedDomain" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScenarioUnspecifiedDomain" xlink:label="ScenarioUnspecifiedDomain_2" xlink:title="ScenarioUnspecifiedDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="StatementScenarioAxis" xlink:to="ScenarioUnspecifiedDomain_2" xlink:title="definition: StatementScenarioAxis to ScenarioUnspecifiedDomain_2" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_AugustTwoThousandNineteenMember" xlink:label="AugustTwoThousandNineteenMember" xlink:title="AugustTwoThousandNineteenMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ScenarioUnspecifiedDomain" xlink:to="AugustTwoThousandNineteenMember" xlink:title="definition: ScenarioUnspecifiedDomain to AugustTwoThousandNineteenMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_AugustTwoThousandTwentyMember" xlink:label="AugustTwoThousandTwentyMember" xlink:title="AugustTwoThousandTwentyMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ScenarioUnspecifiedDomain" xlink:to="AugustTwoThousandTwentyMember" xlink:title="definition: ScenarioUnspecifiedDomain to AugustTwoThousandTwentyMember" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_AprilTwoThousandNineteenMember" xlink:label="AprilTwoThousandNineteenMember" xlink:title="AprilTwoThousandNineteenMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ScenarioUnspecifiedDomain" xlink:to="AprilTwoThousandNineteenMember" xlink:title="definition: ScenarioUnspecifiedDomain to AprilTwoThousandNineteenMember" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_JanuaryTwoThousandEighteenMember" xlink:label="JanuaryTwoThousandEighteenMember" xlink:title="JanuaryTwoThousandEighteenMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ScenarioUnspecifiedDomain" xlink:to="JanuaryTwoThousandEighteenMember" xlink:title="definition: ScenarioUnspecifiedDomain to JanuaryTwoThousandEighteenMember" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_JanuaryTwoThousandNineteenMember" xlink:label="JanuaryTwoThousandNineteenMember" xlink:title="JanuaryTwoThousandNineteenMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ScenarioUnspecifiedDomain" xlink:to="JanuaryTwoThousandNineteenMember" xlink:title="definition: ScenarioUnspecifiedDomain to JanuaryTwoThousandNineteenMember" order="5.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_MayTwoThousandEighteenMember" xlink:label="MayTwoThousandEighteenMember" xlink:title="MayTwoThousandEighteenMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ScenarioUnspecifiedDomain" xlink:to="MayTwoThousandEighteenMember" xlink:title="definition: ScenarioUnspecifiedDomain to MayTwoThousandEighteenMember" order="6.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_MayTwoThousandNineteenMember" xlink:label="MayTwoThousandNineteenMember" xlink:title="MayTwoThousandNineteenMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ScenarioUnspecifiedDomain" xlink:to="MayTwoThousandNineteenMember" xlink:title="definition: ScenarioUnspecifiedDomain to MayTwoThousandNineteenMember" order="7.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_JuneTwoThousandEighteenMember" xlink:label="JuneTwoThousandEighteenMember" xlink:title="JuneTwoThousandEighteenMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ScenarioUnspecifiedDomain" xlink:to="JuneTwoThousandEighteenMember" xlink:title="definition: ScenarioUnspecifiedDomain to JuneTwoThousandEighteenMember" order="8.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_JuneTwoThousandNineteenMember" xlink:label="JuneTwoThousandNineteenMember" xlink:title="JuneTwoThousandNineteenMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ScenarioUnspecifiedDomain" xlink:to="JuneTwoThousandNineteenMember" xlink:title="definition: ScenarioUnspecifiedDomain to JuneTwoThousandNineteenMember" order="9.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_OctoberTwoThousandEighteenMember" xlink:label="OctoberTwoThousandEighteenMember" xlink:title="OctoberTwoThousandEighteenMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ScenarioUnspecifiedDomain" xlink:to="OctoberTwoThousandEighteenMember" xlink:title="definition: ScenarioUnspecifiedDomain to OctoberTwoThousandEighteenMember" order="10.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_OctoberTwoThousandNineteenMember" xlink:label="OctoberTwoThousandNineteenMember" xlink:title="OctoberTwoThousandNineteenMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ScenarioUnspecifiedDomain" xlink:to="OctoberTwoThousandNineteenMember" xlink:title="definition: ScenarioUnspecifiedDomain to OctoberTwoThousandNineteenMember" order="11.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeAxis" xlink:label="RangeAxis" xlink:title="RangeAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:to="RangeAxis" xlink:title="definition: ScheduleOfBusinessAcquisitionsByAcquisitionTable to RangeAxis" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeMember" xlink:label="RangeMember" xlink:title="RangeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="RangeAxis" xlink:to="RangeMember" xlink:title="definition: RangeAxis to RangeMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeMember" xlink:label="RangeMember_2" xlink:title="RangeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="RangeAxis" xlink:to="RangeMember_2" xlink:title="definition: RangeAxis to RangeMember_2" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_MinimumMember" xlink:label="MinimumMember" xlink:title="MinimumMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RangeMember" xlink:to="MinimumMember" xlink:title="definition: RangeMember to MinimumMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_MaximumMember" xlink:label="MaximumMember" xlink:title="MaximumMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RangeMember" xlink:to="MaximumMember" xlink:title="definition: RangeMember to MaximumMember" order="2.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/RevenueRecognitionDetails">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DisaggregationOfRevenueLineItems" xlink:label="DisaggregationOfRevenueLineItems" xlink:title="DisaggregationOfRevenueLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DisaggregationOfRevenueAbstract" xlink:label="DisaggregationOfRevenueAbstract" xlink:title="DisaggregationOfRevenueAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DisaggregationOfRevenueLineItems" xlink:to="DisaggregationOfRevenueAbstract" xlink:title="definition: DisaggregationOfRevenueLineItems to DisaggregationOfRevenueAbstract" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_ContractualAllowancesAbstract" xlink:label="ContractualAllowancesAbstract" xlink:title="ContractualAllowancesAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DisaggregationOfRevenueLineItems" xlink:to="ContractualAllowancesAbstract" xlink:title="definition: DisaggregationOfRevenueLineItems to ContractualAllowancesAbstract" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_MedicareReimbursementAbstract" xlink:label="MedicareReimbursementAbstract" xlink:title="MedicareReimbursementAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DisaggregationOfRevenueLineItems" xlink:to="MedicareReimbursementAbstract" xlink:title="definition: DisaggregationOfRevenueLineItems to MedicareReimbursementAbstract" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_PercentageOfMedicarePaymentIncrease" xlink:label="PercentageOfMedicarePaymentIncrease" xlink:title="PercentageOfMedicarePaymentIncrease" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DisaggregationOfRevenueLineItems" xlink:to="PercentageOfMedicarePaymentIncrease" xlink:title="definition: DisaggregationOfRevenueLineItems to PercentageOfMedicarePaymentIncrease" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_PeriodOfFederalDebtCeilingInConnectionWithDeficitReductions" xlink:label="PeriodOfFederalDebtCeilingInConnectionWithDeficitReductions" xlink:title="PeriodOfFederalDebtCeilingInConnectionWithDeficitReductions" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DisaggregationOfRevenueLineItems" xlink:to="PeriodOfFederalDebtCeilingInConnectionWithDeficitReductions" xlink:title="definition: DisaggregationOfRevenueLineItems to PeriodOfFederalDebtCeilingInConnectionWithDeficitReductions" order="5.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_AmountOfReductionsInFederalSpending" xlink:label="AmountOfReductionsInFederalSpending" xlink:title="AmountOfReductionsInFederalSpending" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DisaggregationOfRevenueLineItems" xlink:to="AmountOfReductionsInFederalSpending" xlink:title="definition: DisaggregationOfRevenueLineItems to AmountOfReductionsInFederalSpending" order="6.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_ReductionInMedicareSpendingPercentage" xlink:label="ReductionInMedicareSpendingPercentage" xlink:title="ReductionInMedicareSpendingPercentage" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DisaggregationOfRevenueLineItems" xlink:to="ReductionInMedicareSpendingPercentage" xlink:title="definition: DisaggregationOfRevenueLineItems to ReductionInMedicareSpendingPercentage" order="7.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_ExpectedReductionInMedicareSpendingPercentage" xlink:label="ExpectedReductionInMedicareSpendingPercentage" xlink:title="ExpectedReductionInMedicareSpendingPercentage" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DisaggregationOfRevenueLineItems" xlink:to="ExpectedReductionInMedicareSpendingPercentage" xlink:title="definition: DisaggregationOfRevenueLineItems to ExpectedReductionInMedicareSpendingPercentage" order="8.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_AnnualLimitOnPhysicalTherapyAndSpeechLanguagePathologyServices" xlink:label="AnnualLimitOnPhysicalTherapyAndSpeechLanguagePathologyServices" xlink:title="AnnualLimitOnPhysicalTherapyAndSpeechLanguagePathologyServices" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DisaggregationOfRevenueLineItems" xlink:to="AnnualLimitOnPhysicalTherapyAndSpeechLanguagePathologyServices" xlink:title="definition: DisaggregationOfRevenueLineItems to AnnualLimitOnPhysicalTherapyAndSpeechLanguagePathologyServices" order="9.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_AnnualLimitOccupationalTherapyServices" xlink:label="AnnualLimitOccupationalTherapyServices" xlink:title="AnnualLimitOccupationalTherapyServices" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DisaggregationOfRevenueLineItems" xlink:to="AnnualLimitOccupationalTherapyServices" xlink:title="definition: DisaggregationOfRevenueLineItems to AnnualLimitOccupationalTherapyServices" order="10.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_CombinedPhysicalTherapySpeechLanguagePathologyExpenses" xlink:label="CombinedPhysicalTherapySpeechLanguagePathologyExpenses" xlink:title="CombinedPhysicalTherapySpeechLanguagePathologyExpenses" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DisaggregationOfRevenueLineItems" xlink:to="CombinedPhysicalTherapySpeechLanguagePathologyExpenses" xlink:title="definition: DisaggregationOfRevenueLineItems to CombinedPhysicalTherapySpeechLanguagePathologyExpenses" order="11.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_ReductionInCombinedPhysicalTherapySpeechLanguagePathologyExpenses" xlink:label="ReductionInCombinedPhysicalTherapySpeechLanguagePathologyExpenses" xlink:title="ReductionInCombinedPhysicalTherapySpeechLanguagePathologyExpenses" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DisaggregationOfRevenueLineItems" xlink:to="ReductionInCombinedPhysicalTherapySpeechLanguagePathologyExpenses" xlink:title="definition: DisaggregationOfRevenueLineItems to ReductionInCombinedPhysicalTherapySpeechLanguagePathologyExpenses" order="12.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_PercentageOfPracticeExpenseComponentOfRelativeValueUnit" xlink:label="PercentageOfPracticeExpenseComponentOfRelativeValueUnit" xlink:title="PercentageOfPracticeExpenseComponentOfRelativeValueUnit" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DisaggregationOfRevenueLineItems" xlink:to="PercentageOfPracticeExpenseComponentOfRelativeValueUnit" xlink:title="definition: DisaggregationOfRevenueLineItems to PercentageOfPracticeExpenseComponentOfRelativeValueUnit" order="13.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_PercentageReductionForServiceInOfficeOrOtherNonInstitutionalSettings" xlink:label="PercentageReductionForServiceInOfficeOrOtherNonInstitutionalSettings" xlink:title="PercentageReductionForServiceInOfficeOrOtherNonInstitutionalSettings" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DisaggregationOfRevenueLineItems" xlink:to="PercentageReductionForServiceInOfficeOrOtherNonInstitutionalSettings" xlink:title="definition: DisaggregationOfRevenueLineItems to PercentageReductionForServiceInOfficeOrOtherNonInstitutionalSettings" order="14.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_PercentageOfPaymentForOutpatientTherapyServices" xlink:label="PercentageOfPaymentForOutpatientTherapyServices" xlink:title="PercentageOfPaymentForOutpatientTherapyServices" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DisaggregationOfRevenueLineItems" xlink:to="PercentageOfPaymentForOutpatientTherapyServices" xlink:title="definition: DisaggregationOfRevenueLineItems to PercentageOfPaymentForOutpatientTherapyServices" order="15.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_NetRevenueFromMedicare" xlink:label="NetRevenueFromMedicare" xlink:title="NetRevenueFromMedicare" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DisaggregationOfRevenueLineItems" xlink:to="NetRevenueFromMedicare" xlink:title="definition: DisaggregationOfRevenueLineItems to NetRevenueFromMedicare" order="16.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_DifferenceBetweenNetRevenuesAndCorrespondingCashCollectionsReflectedPercentageOfNetRevenues" xlink:label="DifferenceBetweenNetRevenuesAndCorrespondingCashCollectionsReflectedPercentageOfNetRevenues" xlink:title="DifferenceBetweenNetRevenuesAndCorrespondingCashCollectionsReflectedPercentageOfNetRevenues" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DisaggregationOfRevenueLineItems" xlink:to="DifferenceBetweenNetRevenuesAndCorrespondingCashCollectionsReflectedPercentageOfNetRevenues" xlink:title="definition: DisaggregationOfRevenueLineItems to DifferenceBetweenNetRevenuesAndCorrespondingCashCollectionsReflectedPercentageOfNetRevenues" order="17.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_DifferenceBetweenActualAggregateContractualReservePercentagesAsComparedToEstimatedContractualAllowanceReservePercentage" xlink:label="DifferenceBetweenActualAggregateContractualReservePercentagesAsComparedToEstimatedContractualAllowanceReservePercentage" xlink:title="DifferenceBetweenActualAggregateContractualReservePercentagesAsComparedToEstimatedContractualAllowanceReservePercentage" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DisaggregationOfRevenueLineItems" xlink:to="DifferenceBetweenActualAggregateContractualReservePercentagesAsComparedToEstimatedContractualAllowanceReservePercentage" xlink:title="definition: DisaggregationOfRevenueLineItems to DifferenceBetweenActualAggregateContractualReservePercentagesAsComparedToEstimatedContractualAllowanceReservePercentage" order="18.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_MaximumContractualAllowanceReserveEstimate" xlink:label="MaximumContractualAllowanceReserveEstimate" xlink:title="MaximumContractualAllowanceReserveEstimate" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DisaggregationOfRevenueLineItems" xlink:to="MaximumContractualAllowanceReserveEstimate" xlink:title="definition: DisaggregationOfRevenueLineItems to MaximumContractualAllowanceReserveEstimate" order="19.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" xlink:label="RevenueFromContractWithCustomerExcludingAssessedTax" xlink:title="RevenueFromContractWithCustomerExcludingAssessedTax" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DisaggregationOfRevenueLineItems" xlink:to="RevenueFromContractWithCustomerExcludingAssessedTax" xlink:title="definition: DisaggregationOfRevenueLineItems to RevenueFromContractWithCustomerExcludingAssessedTax" order="20.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DisaggregationOfRevenueTable" xlink:label="DisaggregationOfRevenueTable" xlink:title="DisaggregationOfRevenueTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="DisaggregationOfRevenueLineItems" xlink:to="DisaggregationOfRevenueTable" xlink:title="definition: DisaggregationOfRevenueLineItems to DisaggregationOfRevenueTable" order="21.0" t1:closed="true" t1:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ProductOrServiceAxis" xlink:label="ProductOrServiceAxis" xlink:title="ProductOrServiceAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="DisaggregationOfRevenueTable" xlink:to="ProductOrServiceAxis" xlink:title="definition: DisaggregationOfRevenueTable to ProductOrServiceAxis" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ProductsAndServicesDomain" xlink:label="ProductsAndServicesDomain" xlink:title="ProductsAndServicesDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="ProductOrServiceAxis" xlink:to="ProductsAndServicesDomain" xlink:title="definition: ProductOrServiceAxis to ProductsAndServicesDomain" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ProductsAndServicesDomain" xlink:label="ProductsAndServicesDomain_2" xlink:title="ProductsAndServicesDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="ProductOrServiceAxis" xlink:to="ProductsAndServicesDomain_2" xlink:title="definition: ProductOrServiceAxis to ProductsAndServicesDomain_2" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_NetPatientRevenuesMember" xlink:label="NetPatientRevenuesMember" xlink:title="NetPatientRevenuesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ProductsAndServicesDomain" xlink:to="NetPatientRevenuesMember" xlink:title="definition: ProductsAndServicesDomain to NetPatientRevenuesMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_ManagementContractRevenuesMember" xlink:label="ManagementContractRevenuesMember" xlink:title="ManagementContractRevenuesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ProductsAndServicesDomain" xlink:to="ManagementContractRevenuesMember" xlink:title="definition: ProductsAndServicesDomain to ManagementContractRevenuesMember" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_IndustrialInjuryPreventionServicesRevenuesMember" xlink:label="IndustrialInjuryPreventionServicesRevenuesMember" xlink:title="IndustrialInjuryPreventionServicesRevenuesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ProductsAndServicesDomain" xlink:to="IndustrialInjuryPreventionServicesRevenuesMember" xlink:title="definition: ProductsAndServicesDomain to IndustrialInjuryPreventionServicesRevenuesMember" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_OtherRevenuesMember" xlink:label="OtherRevenuesMember" xlink:title="OtherRevenuesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ProductsAndServicesDomain" xlink:to="OtherRevenuesMember" xlink:title="definition: ProductsAndServicesDomain to OtherRevenuesMember" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_UnusualOrInfrequentItemAxis" xlink:label="UnusualOrInfrequentItemAxis" xlink:title="UnusualOrInfrequentItemAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="DisaggregationOfRevenueTable" xlink:to="UnusualOrInfrequentItemAxis" xlink:title="definition: DisaggregationOfRevenueTable to UnusualOrInfrequentItemAxis" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_UnusualOrInfrequentItemDomain" xlink:label="UnusualOrInfrequentItemDomain" xlink:title="UnusualOrInfrequentItemDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="UnusualOrInfrequentItemAxis" xlink:to="UnusualOrInfrequentItemDomain" xlink:title="definition: UnusualOrInfrequentItemAxis to UnusualOrInfrequentItemDomain" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_UnusualOrInfrequentItemDomain" xlink:label="UnusualOrInfrequentItemDomain_2" xlink:title="UnusualOrInfrequentItemDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="UnusualOrInfrequentItemAxis" xlink:to="UnusualOrInfrequentItemDomain_2" xlink:title="definition: UnusualOrInfrequentItemAxis to UnusualOrInfrequentItemDomain_2" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_Year2017Member" xlink:label="Year2017Member" xlink:title="Year2017Member" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="UnusualOrInfrequentItemDomain" xlink:to="Year2017Member" xlink:title="definition: UnusualOrInfrequentItemDomain to Year2017Member" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_Year2018Member" xlink:label="Year2018Member" xlink:title="Year2018Member" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="UnusualOrInfrequentItemDomain" xlink:to="Year2018Member" xlink:title="definition: UnusualOrInfrequentItemDomain to Year2018Member" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_Year2019Member" xlink:label="Year2019Member" xlink:title="Year2019Member" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="UnusualOrInfrequentItemDomain" xlink:to="Year2019Member" xlink:title="definition: UnusualOrInfrequentItemDomain to Year2019Member" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_FromTwoThousandNineteenThroughTwoThousandTwentyFourMember" xlink:label="FromTwoThousandNineteenThroughTwoThousandTwentyFourMember" xlink:title="FromTwoThousandNineteenThroughTwoThousandTwentyFourMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="UnusualOrInfrequentItemDomain" xlink:to="FromTwoThousandNineteenThroughTwoThousandTwentyFourMember" xlink:title="definition: UnusualOrInfrequentItemDomain to FromTwoThousandNineteenThroughTwoThousandTwentyFourMember" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_FromTwoThousandTwentyThroughTwoThousandTwentyFiveMember" xlink:label="FromTwoThousandTwentyThroughTwoThousandTwentyFiveMember" xlink:title="FromTwoThousandTwentyThroughTwoThousandTwentyFiveMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="UnusualOrInfrequentItemDomain" xlink:to="FromTwoThousandTwentyThroughTwoThousandTwentyFiveMember" xlink:title="definition: UnusualOrInfrequentItemDomain to FromTwoThousandTwentyThroughTwoThousandTwentyFiveMember" order="5.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeAxis" xlink:label="RangeAxis" xlink:title="RangeAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="DisaggregationOfRevenueTable" xlink:to="RangeAxis" xlink:title="definition: DisaggregationOfRevenueTable to RangeAxis" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeMember" xlink:label="RangeMember" xlink:title="RangeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="RangeAxis" xlink:to="RangeMember" xlink:title="definition: RangeAxis to RangeMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeMember" xlink:label="RangeMember_2" xlink:title="RangeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="RangeAxis" xlink:to="RangeMember_2" xlink:title="definition: RangeAxis to RangeMember_2" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_MaximumMember" xlink:label="MaximumMember" xlink:title="MaximumMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RangeMember" xlink:to="MaximumMember" xlink:title="definition: RangeMember to MaximumMember" order="1.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/EarningsPerShareDetails" />
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/MandatorilyRedeemableNoncontrollingInterestsDetails">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessAcquisitionLineItems" xlink:label="BusinessAcquisitionLineItems" xlink:title="BusinessAcquisitionLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessCombinationDescriptionAbstract" xlink:label="BusinessCombinationDescriptionAbstract" xlink:title="BusinessCombinationDescriptionAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessCombinationDescriptionAbstract" xlink:title="definition: BusinessAcquisitionLineItems to BusinessCombinationDescriptionAbstract" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_BusinessAcquisitionPercentageOfEquityInterestInSubsidiaryContributed" xlink:label="BusinessAcquisitionPercentageOfEquityInterestInSubsidiaryContributed" xlink:title="BusinessAcquisitionPercentageOfEquityInterestInSubsidiaryContributed" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessAcquisitionPercentageOfEquityInterestInSubsidiaryContributed" xlink:title="definition: BusinessAcquisitionLineItems to BusinessAcquisitionPercentageOfEquityInterestInSubsidiaryContributed" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_BusinessAcquisitionPercentageOfLimitedPartnershipInterestAcquired" xlink:label="BusinessAcquisitionPercentageOfLimitedPartnershipInterestAcquired" xlink:title="BusinessAcquisitionPercentageOfLimitedPartnershipInterestAcquired" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessAcquisitionPercentageOfLimitedPartnershipInterestAcquired" xlink:title="definition: BusinessAcquisitionLineItems to BusinessAcquisitionPercentageOfLimitedPartnershipInterestAcquired" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_BusinessAcquisitionPercentageOfGeneralPartnershipInterestAcquired" xlink:label="BusinessAcquisitionPercentageOfGeneralPartnershipInterestAcquired" xlink:title="BusinessAcquisitionPercentageOfGeneralPartnershipInterestAcquired" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessAcquisitionPercentageOfGeneralPartnershipInterestAcquired" xlink:title="definition: BusinessAcquisitionLineItems to BusinessAcquisitionPercentageOfGeneralPartnershipInterestAcquired" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_BusinessAcquisitionConsiderationPayableTermOfNote" xlink:label="BusinessAcquisitionConsiderationPayableTermOfNote" xlink:title="BusinessAcquisitionConsiderationPayableTermOfNote" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessAcquisitionConsiderationPayableTermOfNote" xlink:title="definition: BusinessAcquisitionLineItems to BusinessAcquisitionConsiderationPayableTermOfNote" order="5.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_TermOfEmploymentAgreement" xlink:label="TermOfEmploymentAgreement" xlink:title="TermOfEmploymentAgreement" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="TermOfEmploymentAgreement" xlink:title="definition: BusinessAcquisitionLineItems to TermOfEmploymentAgreement" order="6.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_EmploymentAgreementRenewalTerm" xlink:label="EmploymentAgreementRenewalTerm" xlink:title="EmploymentAgreementRenewalTerm" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="EmploymentAgreementRenewalTerm" xlink:title="definition: BusinessAcquisitionLineItems to EmploymentAgreementRenewalTerm" order="7.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_NonCompeteAgreementTermUnderConditionOfTerminationOfEmploymentOfEmployedSellingShareholder" xlink:label="NonCompeteAgreementTermUnderConditionOfTerminationOfEmploymentOfEmployedSellingShareholder" xlink:title="NonCompeteAgreementTermUnderConditionOfTerminationOfEmploymentOfEmployedSellingShareholder" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="NonCompeteAgreementTermUnderConditionOfTerminationOfEmploymentOfEmployedSellingShareholder" xlink:title="definition: BusinessAcquisitionLineItems to NonCompeteAgreementTermUnderConditionOfTerminationOfEmploymentOfEmployedSellingShareholder" order="8.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_NonCompeteAgreementBasicTerm" xlink:label="NonCompeteAgreementBasicTerm" xlink:title="NonCompeteAgreementBasicTerm" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="NonCompeteAgreementBasicTerm" xlink:title="definition: BusinessAcquisitionLineItems to NonCompeteAgreementBasicTerm" order="9.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_RequiredRedemptionTermUnderConditionOfTerminationOfEmploymentOfEmployedSellingShareholders" xlink:label="RequiredRedemptionTermUnderConditionOfTerminationOfEmploymentOfEmployedSellingShareholders" xlink:title="RequiredRedemptionTermUnderConditionOfTerminationOfEmploymentOfEmployedSellingShareholders" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="RequiredRedemptionTermUnderConditionOfTerminationOfEmploymentOfEmployedSellingShareholders" xlink:title="definition: BusinessAcquisitionLineItems to RequiredRedemptionTermUnderConditionOfTerminationOfEmploymentOfEmployedSellingShareholders" order="10.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:label="ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:title="ScheduleOfBusinessAcquisitionsByAcquisitionTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="BusinessAcquisitionLineItems" xlink:to="ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:title="definition: BusinessAcquisitionLineItems to ScheduleOfBusinessAcquisitionsByAcquisitionTable" order="11.0" t1:closed="true" t1:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessAcquisitionAxis" xlink:label="BusinessAcquisitionAxis" xlink:title="BusinessAcquisitionAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:to="BusinessAcquisitionAxis" xlink:title="definition: ScheduleOfBusinessAcquisitionsByAcquisitionTable to BusinessAcquisitionAxis" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="BusinessAcquisitionAcquireeDomain" xlink:title="BusinessAcquisitionAcquireeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="BusinessAcquisitionAxis" xlink:to="BusinessAcquisitionAcquireeDomain" xlink:title="definition: BusinessAcquisitionAxis to BusinessAcquisitionAcquireeDomain" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="BusinessAcquisitionAcquireeDomain_2" xlink:title="BusinessAcquisitionAcquireeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="BusinessAcquisitionAxis" xlink:to="BusinessAcquisitionAcquireeDomain_2" xlink:title="definition: BusinessAcquisitionAxis to BusinessAcquisitionAcquireeDomain_2" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_TherapyPracticeMember" xlink:label="TherapyPracticeMember" xlink:title="TherapyPracticeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionAcquireeDomain" xlink:to="TherapyPracticeMember" xlink:title="definition: BusinessAcquisitionAcquireeDomain to TherapyPracticeMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ConsolidatedEntitiesAxis" xlink:label="ConsolidatedEntitiesAxis" xlink:title="ConsolidatedEntitiesAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:to="ConsolidatedEntitiesAxis" xlink:title="definition: ScheduleOfBusinessAcquisitionsByAcquisitionTable to ConsolidatedEntitiesAxis" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="ConsolidatedEntitiesDomain" xlink:title="ConsolidatedEntitiesDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="ConsolidatedEntitiesAxis" xlink:to="ConsolidatedEntitiesDomain" xlink:title="definition: ConsolidatedEntitiesAxis to ConsolidatedEntitiesDomain" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="ConsolidatedEntitiesDomain_2" xlink:title="ConsolidatedEntitiesDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="ConsolidatedEntitiesAxis" xlink:to="ConsolidatedEntitiesDomain_2" xlink:title="definition: ConsolidatedEntitiesAxis to ConsolidatedEntitiesDomain_2" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_SubsidiariesMember" xlink:label="SubsidiariesMember" xlink:title="SubsidiariesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ConsolidatedEntitiesDomain" xlink:to="SubsidiariesMember" xlink:title="definition: ConsolidatedEntitiesDomain to SubsidiariesMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeAxis" xlink:label="RangeAxis" xlink:title="RangeAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:to="RangeAxis" xlink:title="definition: ScheduleOfBusinessAcquisitionsByAcquisitionTable to RangeAxis" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeMember" xlink:label="RangeMember" xlink:title="RangeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="RangeAxis" xlink:to="RangeMember" xlink:title="definition: RangeAxis to RangeMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeMember" xlink:label="RangeMember_2" xlink:title="RangeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="RangeAxis" xlink:to="RangeMember_2" xlink:title="definition: RangeAxis to RangeMember_2" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_MinimumMember" xlink:label="MinimumMember" xlink:title="MinimumMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RangeMember" xlink:to="MinimumMember" xlink:title="definition: RangeMember to MinimumMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_MaximumMember" xlink:label="MaximumMember" xlink:title="MaximumMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RangeMember" xlink:to="MaximumMember" xlink:title="definition: RangeMember to MaximumMember" order="2.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/RedeemableNoncontrollingInterestsDetails">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RedeemableNoncontrollingInterestLineItems" xlink:label="RedeemableNoncontrollingInterestLineItems" xlink:title="RedeemableNoncontrollingInterestLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RedeemableNoncontrollingInterestEquityCarryingAmountAbstract" xlink:label="RedeemableNoncontrollingInterestEquityCarryingAmountAbstract" xlink:title="RedeemableNoncontrollingInterestEquityCarryingAmountAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RedeemableNoncontrollingInterestLineItems" xlink:to="RedeemableNoncontrollingInterestEquityCarryingAmountAbstract" xlink:title="definition: RedeemableNoncontrollingInterestLineItems to RedeemableNoncontrollingInterestEquityCarryingAmountAbstract" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_CarryingAmountOfRedeemableNonControllingInterestAbstract" xlink:label="CarryingAmountOfRedeemableNonControllingInterestAbstract" xlink:title="CarryingAmountOfRedeemableNonControllingInterestAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RedeemableNoncontrollingInterestLineItems" xlink:to="CarryingAmountOfRedeemableNonControllingInterestAbstract" xlink:title="definition: RedeemableNoncontrollingInterestLineItems to CarryingAmountOfRedeemableNonControllingInterestAbstract" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_ContractualTimePeriodHasLapsedButHoldersEmploymentHasNotBeenTerminated" xlink:label="ContractualTimePeriodHasLapsedButHoldersEmploymentHasNotBeenTerminated" xlink:title="ContractualTimePeriodHasLapsedButHoldersEmploymentHasNotBeenTerminated" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RedeemableNoncontrollingInterestLineItems" xlink:to="ContractualTimePeriodHasLapsedButHoldersEmploymentHasNotBeenTerminated" xlink:title="definition: RedeemableNoncontrollingInterestLineItems to ContractualTimePeriodHasLapsedButHoldersEmploymentHasNotBeenTerminated" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_ContractualTimePeriodHadNotLapsedAndHoldersEmploymentHadNotBeenTerminated" xlink:label="ContractualTimePeriodHadNotLapsedAndHoldersEmploymentHadNotBeenTerminated" xlink:title="ContractualTimePeriodHadNotLapsedAndHoldersEmploymentHadNotBeenTerminated" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RedeemableNoncontrollingInterestLineItems" xlink:to="ContractualTimePeriodHadNotLapsedAndHoldersEmploymentHadNotBeenTerminated" xlink:title="definition: RedeemableNoncontrollingInterestLineItems to ContractualTimePeriodHadNotLapsedAndHoldersEmploymentHadNotBeenTerminated" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RedeemableNoncontrollingInterestEquityCarryingAmount" xlink:label="RedeemableNoncontrollingInterestEquityCarryingAmount" xlink:title="RedeemableNoncontrollingInterestEquityCarryingAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RedeemableNoncontrollingInterestLineItems" xlink:to="RedeemableNoncontrollingInterestEquityCarryingAmount" xlink:title="definition: RedeemableNoncontrollingInterestLineItems to RedeemableNoncontrollingInterestEquityCarryingAmount" order="5.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NetIncomeLossAttributableToRedeemableNoncontrollingInterest" xlink:label="NetIncomeLossAttributableToRedeemableNoncontrollingInterest" xlink:title="NetIncomeLossAttributableToRedeemableNoncontrollingInterest" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RedeemableNoncontrollingInterestLineItems" xlink:to="NetIncomeLossAttributableToRedeemableNoncontrollingInterest" xlink:title="definition: RedeemableNoncontrollingInterestLineItems to NetIncomeLossAttributableToRedeemableNoncontrollingInterest" order="6.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_DistributionsToLimitedPartnersAndRedeemableNoncontrollingInterests" xlink:label="DistributionsToLimitedPartnersAndRedeemableNoncontrollingInterests" xlink:title="DistributionsToLimitedPartnersAndRedeemableNoncontrollingInterests" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RedeemableNoncontrollingInterestLineItems" xlink:to="DistributionsToLimitedPartnersAndRedeemableNoncontrollingInterests" xlink:title="definition: RedeemableNoncontrollingInterestLineItems to DistributionsToLimitedPartnersAndRedeemableNoncontrollingInterests" order="7.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NoncontrollingInterestIncreaseFromSaleOfParentEquityInterest" xlink:label="NoncontrollingInterestIncreaseFromSaleOfParentEquityInterest" xlink:title="NoncontrollingInterestIncreaseFromSaleOfParentEquityInterest" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RedeemableNoncontrollingInterestLineItems" xlink:to="NoncontrollingInterestIncreaseFromSaleOfParentEquityInterest" xlink:title="definition: RedeemableNoncontrollingInterestLineItems to NoncontrollingInterestIncreaseFromSaleOfParentEquityInterest" order="8.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PaymentsToMinorityShareholders" xlink:label="PaymentsToMinorityShareholders" xlink:title="PaymentsToMinorityShareholders" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RedeemableNoncontrollingInterestLineItems" xlink:to="PaymentsToMinorityShareholders" xlink:title="definition: RedeemableNoncontrollingInterestLineItems to PaymentsToMinorityShareholders" order="9.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NoncontrollingInterestInNetIncomeLossOtherNoncontrollingInterestsRedeemable" xlink:label="NoncontrollingInterestInNetIncomeLossOtherNoncontrollingInterestsRedeemable" xlink:title="NoncontrollingInterestInNetIncomeLossOtherNoncontrollingInterestsRedeemable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RedeemableNoncontrollingInterestLineItems" xlink:to="NoncontrollingInterestInNetIncomeLossOtherNoncontrollingInterestsRedeemable" xlink:title="definition: RedeemableNoncontrollingInterestLineItems to NoncontrollingInterestInNetIncomeLossOtherNoncontrollingInterestsRedeemable" order="10.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RedeemableNoncontrollingInterestByLegalEntityTable" xlink:label="RedeemableNoncontrollingInterestByLegalEntityTable" xlink:title="RedeemableNoncontrollingInterestByLegalEntityTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="RedeemableNoncontrollingInterestLineItems" xlink:to="RedeemableNoncontrollingInterestByLegalEntityTable" xlink:title="definition: RedeemableNoncontrollingInterestLineItems to RedeemableNoncontrollingInterestByLegalEntityTable" order="11.0" t1:closed="true" t1:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_OwnershipAxis" xlink:label="OwnershipAxis" xlink:title="OwnershipAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="RedeemableNoncontrollingInterestByLegalEntityTable" xlink:to="OwnershipAxis" xlink:title="definition: RedeemableNoncontrollingInterestByLegalEntityTable to OwnershipAxis" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_OwnershipDomain" xlink:label="OwnershipDomain" xlink:title="OwnershipDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="OwnershipAxis" xlink:to="OwnershipDomain" xlink:title="definition: OwnershipAxis to OwnershipDomain" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_OwnershipDomain" xlink:label="OwnershipDomain_2" xlink:title="OwnershipDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="OwnershipAxis" xlink:to="OwnershipDomain_2" xlink:title="definition: OwnershipAxis to OwnershipDomain_2" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_RedeemableNonControllingInterestMember" xlink:label="RedeemableNonControllingInterestMember" xlink:title="RedeemableNonControllingInterestMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="OwnershipDomain" xlink:to="RedeemableNonControllingInterestMember" xlink:title="definition: OwnershipDomain to RedeemableNonControllingInterestMember" order="1.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/GoodwillDetails" />
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/IntangibleAssetsNetIntangibleAssetsNetDetails">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsLineItems" xlink:label="FiniteLivedIntangibleAssetsLineItems" xlink:title="FiniteLivedIntangibleAssetsLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsNetAbstract" xlink:label="FiniteLivedIntangibleAssetsNetAbstract" xlink:title="FiniteLivedIntangibleAssetsNetAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsLineItems" xlink:to="FiniteLivedIntangibleAssetsNetAbstract" xlink:title="definition: FiniteLivedIntangibleAssetsLineItems to FiniteLivedIntangibleAssetsNetAbstract" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IntangibleAssetsNetExcludingGoodwill" xlink:label="IntangibleAssetsNetExcludingGoodwill" xlink:title="IntangibleAssetsNetExcludingGoodwill" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsLineItems" xlink:to="IntangibleAssetsNetExcludingGoodwill" xlink:title="definition: FiniteLivedIntangibleAssetsLineItems to IntangibleAssetsNetExcludingGoodwill" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization" xlink:label="FiniteLivedIntangibleAssetsAccumulatedAmortization" xlink:title="FiniteLivedIntangibleAssetsAccumulatedAmortization" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsLineItems" xlink:to="FiniteLivedIntangibleAssetsAccumulatedAmortization" xlink:title="definition: FiniteLivedIntangibleAssetsLineItems to FiniteLivedIntangibleAssetsAccumulatedAmortization" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetUsefulLife" xlink:label="FiniteLivedIntangibleAssetUsefulLife" xlink:title="FiniteLivedIntangibleAssetUsefulLife" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsLineItems" xlink:to="FiniteLivedIntangibleAssetUsefulLife" xlink:title="definition: FiniteLivedIntangibleAssetsLineItems to FiniteLivedIntangibleAssetUsefulLife" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable" xlink:label="ScheduleOfFiniteLivedIntangibleAssetsTable" xlink:title="ScheduleOfFiniteLivedIntangibleAssetsTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="FiniteLivedIntangibleAssetsLineItems" xlink:to="ScheduleOfFiniteLivedIntangibleAssetsTable" xlink:title="definition: FiniteLivedIntangibleAssetsLineItems to ScheduleOfFiniteLivedIntangibleAssetsTable" order="5.0" t1:closed="true" t1:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:label="FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:title="FiniteLivedIntangibleAssetsByMajorClassAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfFiniteLivedIntangibleAssetsTable" xlink:to="FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:title="definition: ScheduleOfFiniteLivedIntangibleAssetsTable to FiniteLivedIntangibleAssetsByMajorClassAxis" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:title="FiniteLivedIntangibleAssetsMajorClassNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:to="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:title="definition: FiniteLivedIntangibleAssetsByMajorClassAxis to FiniteLivedIntangibleAssetsMajorClassNameDomain" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="FiniteLivedIntangibleAssetsMajorClassNameDomain_2" xlink:title="FiniteLivedIntangibleAssetsMajorClassNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:to="FiniteLivedIntangibleAssetsMajorClassNameDomain_2" xlink:title="definition: FiniteLivedIntangibleAssetsByMajorClassAxis to FiniteLivedIntangibleAssetsMajorClassNameDomain_2" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TrademarksMember" xlink:label="TrademarksMember" xlink:title="TrademarksMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="TrademarksMember" xlink:title="definition: FiniteLivedIntangibleAssetsMajorClassNameDomain to TrademarksMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_ReferralRelationshipMember" xlink:label="ReferralRelationshipMember" xlink:title="ReferralRelationshipMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="ReferralRelationshipMember" xlink:title="definition: FiniteLivedIntangibleAssetsMajorClassNameDomain to ReferralRelationshipMember" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NoncompeteAgreementsMember" xlink:label="NoncompeteAgreementsMember" xlink:title="NoncompeteAgreementsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="NoncompeteAgreementsMember" xlink:title="definition: FiniteLivedIntangibleAssetsMajorClassNameDomain to NoncompeteAgreementsMember" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeAxis" xlink:label="RangeAxis" xlink:title="RangeAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfFiniteLivedIntangibleAssetsTable" xlink:to="RangeAxis" xlink:title="definition: ScheduleOfFiniteLivedIntangibleAssetsTable to RangeAxis" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeMember" xlink:label="RangeMember" xlink:title="RangeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="RangeAxis" xlink:to="RangeMember" xlink:title="definition: RangeAxis to RangeMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeMember" xlink:label="RangeMember_2" xlink:title="RangeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="RangeAxis" xlink:to="RangeMember_2" xlink:title="definition: RangeAxis to RangeMember_2" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_MinimumMember" xlink:label="MinimumMember" xlink:title="MinimumMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RangeMember" xlink:to="MinimumMember" xlink:title="definition: RangeMember to MinimumMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_MaximumMember" xlink:label="MaximumMember" xlink:title="MaximumMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RangeMember" xlink:to="MaximumMember" xlink:title="definition: RangeMember to MaximumMember" order="2.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/IntangibleAssetsNetAmortizationExpensesDetails">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsLineItems" xlink:label="FiniteLivedIntangibleAssetsLineItems" xlink:title="FiniteLivedIntangibleAssetsLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AmortizationOfDeferredChargesAbstract" xlink:label="AmortizationOfDeferredChargesAbstract" xlink:title="AmortizationOfDeferredChargesAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsLineItems" xlink:to="AmortizationOfDeferredChargesAbstract" xlink:title="definition: FiniteLivedIntangibleAssetsLineItems to AmortizationOfDeferredChargesAbstract" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AmortizationOfIntangibleAssets" xlink:label="AmortizationOfIntangibleAssets" xlink:title="AmortizationOfIntangibleAssets" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsLineItems" xlink:to="AmortizationOfIntangibleAssets" xlink:title="definition: FiniteLivedIntangibleAssetsLineItems to AmortizationOfIntangibleAssets" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable" xlink:label="ScheduleOfFiniteLivedIntangibleAssetsTable" xlink:title="ScheduleOfFiniteLivedIntangibleAssetsTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="FiniteLivedIntangibleAssetsLineItems" xlink:to="ScheduleOfFiniteLivedIntangibleAssetsTable" xlink:title="definition: FiniteLivedIntangibleAssetsLineItems to ScheduleOfFiniteLivedIntangibleAssetsTable" order="3.0" t1:closed="true" t1:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:label="FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:title="FiniteLivedIntangibleAssetsByMajorClassAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfFiniteLivedIntangibleAssetsTable" xlink:to="FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:title="definition: ScheduleOfFiniteLivedIntangibleAssetsTable to FiniteLivedIntangibleAssetsByMajorClassAxis" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:title="FiniteLivedIntangibleAssetsMajorClassNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:to="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:title="definition: FiniteLivedIntangibleAssetsByMajorClassAxis to FiniteLivedIntangibleAssetsMajorClassNameDomain" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="FiniteLivedIntangibleAssetsMajorClassNameDomain_2" xlink:title="FiniteLivedIntangibleAssetsMajorClassNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:to="FiniteLivedIntangibleAssetsMajorClassNameDomain_2" xlink:title="definition: FiniteLivedIntangibleAssetsByMajorClassAxis to FiniteLivedIntangibleAssetsMajorClassNameDomain_2" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_ReferralRelationshipMember" xlink:label="ReferralRelationshipMember" xlink:title="ReferralRelationshipMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="ReferralRelationshipMember" xlink:title="definition: FiniteLivedIntangibleAssetsMajorClassNameDomain to ReferralRelationshipMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NoncompeteAgreementsMember" xlink:label="NoncompeteAgreementsMember" xlink:title="NoncompeteAgreementsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="NoncompeteAgreementsMember" xlink:title="definition: FiniteLivedIntangibleAssetsMajorClassNameDomain to NoncompeteAgreementsMember" order="2.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/IntangibleAssetsNetAmortizationOfTradenameReferralRelationshipsAndNoncompetitionAgreementsDetails">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsLineItems" xlink:label="FiniteLivedIntangibleAssetsLineItems" xlink:title="FiniteLivedIntangibleAssetsLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsFutureAmortizationExpenseCurrentAndFiveSucceedingFiscalYearsAbstract" xlink:label="FiniteLivedIntangibleAssetsFutureAmortizationExpenseCurrentAndFiveSucceedingFiscalYearsAbstract" xlink:title="FiniteLivedIntangibleAssetsFutureAmortizationExpenseCurrentAndFiveSucceedingFiscalYearsAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsLineItems" xlink:to="FiniteLivedIntangibleAssetsFutureAmortizationExpenseCurrentAndFiveSucceedingFiscalYearsAbstract" xlink:title="definition: FiniteLivedIntangibleAssetsLineItems to FiniteLivedIntangibleAssetsFutureAmortizationExpenseCurrentAndFiveSucceedingFiscalYearsAbstract" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear" xlink:label="FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear" xlink:title="FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsLineItems" xlink:to="FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear" xlink:title="definition: FiniteLivedIntangibleAssetsLineItems to FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextRollingTwelveMonths" xlink:label="FiniteLivedIntangibleAssetsAmortizationExpenseNextRollingTwelveMonths" xlink:title="FiniteLivedIntangibleAssetsAmortizationExpenseNextRollingTwelveMonths" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsLineItems" xlink:to="FiniteLivedIntangibleAssetsAmortizationExpenseNextRollingTwelveMonths" xlink:title="definition: FiniteLivedIntangibleAssetsLineItems to FiniteLivedIntangibleAssetsAmortizationExpenseNextRollingTwelveMonths" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRollingYearTwo" xlink:label="FiniteLivedIntangibleAssetsAmortizationExpenseRollingYearTwo" xlink:title="FiniteLivedIntangibleAssetsAmortizationExpenseRollingYearTwo" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsLineItems" xlink:to="FiniteLivedIntangibleAssetsAmortizationExpenseRollingYearTwo" xlink:title="definition: FiniteLivedIntangibleAssetsLineItems to FiniteLivedIntangibleAssetsAmortizationExpenseRollingYearTwo" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRollingYearThree" xlink:label="FiniteLivedIntangibleAssetsAmortizationExpenseRollingYearThree" xlink:title="FiniteLivedIntangibleAssetsAmortizationExpenseRollingYearThree" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsLineItems" xlink:to="FiniteLivedIntangibleAssetsAmortizationExpenseRollingYearThree" xlink:title="definition: FiniteLivedIntangibleAssetsLineItems to FiniteLivedIntangibleAssetsAmortizationExpenseRollingYearThree" order="5.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRollingYearFour" xlink:label="FiniteLivedIntangibleAssetsAmortizationExpenseRollingYearFour" xlink:title="FiniteLivedIntangibleAssetsAmortizationExpenseRollingYearFour" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsLineItems" xlink:to="FiniteLivedIntangibleAssetsAmortizationExpenseRollingYearFour" xlink:title="definition: FiniteLivedIntangibleAssetsLineItems to FiniteLivedIntangibleAssetsAmortizationExpenseRollingYearFour" order="6.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRollingYearFive" xlink:label="FiniteLivedIntangibleAssetsAmortizationExpenseRollingYearFive" xlink:title="FiniteLivedIntangibleAssetsAmortizationExpenseRollingYearFive" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsLineItems" xlink:to="FiniteLivedIntangibleAssetsAmortizationExpenseRollingYearFive" xlink:title="definition: FiniteLivedIntangibleAssetsLineItems to FiniteLivedIntangibleAssetsAmortizationExpenseRollingYearFive" order="7.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRollingAfterYearFive" xlink:label="FiniteLivedIntangibleAssetsAmortizationExpenseRollingAfterYearFive" xlink:title="FiniteLivedIntangibleAssetsAmortizationExpenseRollingAfterYearFive" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsLineItems" xlink:to="FiniteLivedIntangibleAssetsAmortizationExpenseRollingAfterYearFive" xlink:title="definition: FiniteLivedIntangibleAssetsLineItems to FiniteLivedIntangibleAssetsAmortizationExpenseRollingAfterYearFive" order="8.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable" xlink:label="ScheduleOfFiniteLivedIntangibleAssetsTable" xlink:title="ScheduleOfFiniteLivedIntangibleAssetsTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="FiniteLivedIntangibleAssetsLineItems" xlink:to="ScheduleOfFiniteLivedIntangibleAssetsTable" xlink:title="definition: FiniteLivedIntangibleAssetsLineItems to ScheduleOfFiniteLivedIntangibleAssetsTable" order="9.0" t1:closed="true" t1:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:label="FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:title="FiniteLivedIntangibleAssetsByMajorClassAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfFiniteLivedIntangibleAssetsTable" xlink:to="FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:title="definition: ScheduleOfFiniteLivedIntangibleAssetsTable to FiniteLivedIntangibleAssetsByMajorClassAxis" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:title="FiniteLivedIntangibleAssetsMajorClassNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:to="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:title="definition: FiniteLivedIntangibleAssetsByMajorClassAxis to FiniteLivedIntangibleAssetsMajorClassNameDomain" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="FiniteLivedIntangibleAssetsMajorClassNameDomain_2" xlink:title="FiniteLivedIntangibleAssetsMajorClassNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:to="FiniteLivedIntangibleAssetsMajorClassNameDomain_2" xlink:title="definition: FiniteLivedIntangibleAssetsByMajorClassAxis to FiniteLivedIntangibleAssetsMajorClassNameDomain_2" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_ReferralRelationshipMember" xlink:label="ReferralRelationshipMember" xlink:title="ReferralRelationshipMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="ReferralRelationshipMember" xlink:title="definition: FiniteLivedIntangibleAssetsMajorClassNameDomain to ReferralRelationshipMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NoncompeteAgreementsMember" xlink:label="NoncompeteAgreementsMember" xlink:title="NoncompeteAgreementsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="NoncompeteAgreementsMember" xlink:title="definition: FiniteLivedIntangibleAssetsMajorClassNameDomain to NoncompeteAgreementsMember" order="2.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/AccruedExpensesDetails" />
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/NotesPayableAndAmendedCreditAgreementSummaryOfNotesPayableAndCreditAgreementDetails">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentLineItems" xlink:label="DebtInstrumentLineItems" xlink:title="DebtInstrumentLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentsAbstract" xlink:label="DebtInstrumentsAbstract" xlink:title="DebtInstrumentsAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="DebtInstrumentsAbstract" xlink:title="definition: DebtInstrumentLineItems to DebtInstrumentsAbstract" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongTermDebt" xlink:label="LongTermDebt" xlink:title="LongTermDebt" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="LongTermDebt" xlink:title="definition: DebtInstrumentLineItems to LongTermDebt" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongTermDebtCurrent" xlink:label="LongTermDebtCurrent" xlink:title="LongTermDebtCurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="LongTermDebtCurrent" xlink:title="definition: DebtInstrumentLineItems to LongTermDebtCurrent" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongTermDebtNoncurrent" xlink:label="LongTermDebtNoncurrent" xlink:title="LongTermDebtNoncurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="LongTermDebtNoncurrent" xlink:title="definition: DebtInstrumentLineItems to LongTermDebtNoncurrent" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LineOfCreditFacilityInterestRateDuringPeriod" xlink:label="LineOfCreditFacilityInterestRateDuringPeriod" xlink:title="LineOfCreditFacilityInterestRateDuringPeriod" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="LineOfCreditFacilityInterestRateDuringPeriod" xlink:title="definition: DebtInstrumentLineItems to LineOfCreditFacilityInterestRateDuringPeriod" order="5.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentAnnualPrincipalPayment" xlink:label="DebtInstrumentAnnualPrincipalPayment" xlink:title="DebtInstrumentAnnualPrincipalPayment" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="DebtInstrumentAnnualPrincipalPayment" xlink:title="definition: DebtInstrumentLineItems to DebtInstrumentAnnualPrincipalPayment" order="6.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage" xlink:label="DebtInstrumentInterestRateStatedPercentage" xlink:title="DebtInstrumentInterestRateStatedPercentage" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="DebtInstrumentInterestRateStatedPercentage" xlink:title="definition: DebtInstrumentLineItems to DebtInstrumentInterestRateStatedPercentage" order="7.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentTable" xlink:label="DebtInstrumentTable" xlink:title="DebtInstrumentTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="DebtInstrumentLineItems" xlink:to="DebtInstrumentTable" xlink:title="definition: DebtInstrumentLineItems to DebtInstrumentTable" order="8.0" t1:closed="true" t1:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentAxis" xlink:label="DebtInstrumentAxis" xlink:title="DebtInstrumentAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="DebtInstrumentTable" xlink:to="DebtInstrumentAxis" xlink:title="definition: DebtInstrumentTable to DebtInstrumentAxis" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="DebtInstrumentNameDomain" xlink:title="DebtInstrumentNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="DebtInstrumentAxis" xlink:to="DebtInstrumentNameDomain" xlink:title="definition: DebtInstrumentAxis to DebtInstrumentNameDomain" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="DebtInstrumentNameDomain_2" xlink:title="DebtInstrumentNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="DebtInstrumentAxis" xlink:to="DebtInstrumentNameDomain_2" xlink:title="definition: DebtInstrumentAxis to DebtInstrumentNameDomain_2" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_PromissoryNotesMember" xlink:label="PromissoryNotesMember" xlink:title="PromissoryNotesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentNameDomain" xlink:to="PromissoryNotesMember" xlink:title="definition: DebtInstrumentNameDomain to PromissoryNotesMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CreditFacilityAxis" xlink:label="CreditFacilityAxis" xlink:title="CreditFacilityAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="DebtInstrumentTable" xlink:to="CreditFacilityAxis" xlink:title="definition: DebtInstrumentTable to CreditFacilityAxis" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CreditFacilityDomain" xlink:label="CreditFacilityDomain" xlink:title="CreditFacilityDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="CreditFacilityAxis" xlink:to="CreditFacilityDomain" xlink:title="definition: CreditFacilityAxis to CreditFacilityDomain" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CreditFacilityDomain" xlink:label="CreditFacilityDomain_2" xlink:title="CreditFacilityDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="CreditFacilityAxis" xlink:to="CreditFacilityDomain_2" xlink:title="definition: CreditFacilityAxis to CreditFacilityDomain_2" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RevolvingCreditFacilityMember" xlink:label="RevolvingCreditFacilityMember" xlink:title="RevolvingCreditFacilityMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="CreditFacilityDomain" xlink:to="RevolvingCreditFacilityMember" xlink:title="definition: CreditFacilityDomain to RevolvingCreditFacilityMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeAxis" xlink:label="RangeAxis" xlink:title="RangeAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="DebtInstrumentTable" xlink:to="RangeAxis" xlink:title="definition: DebtInstrumentTable to RangeAxis" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeMember" xlink:label="RangeMember" xlink:title="RangeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="RangeAxis" xlink:to="RangeMember" xlink:title="definition: RangeAxis to RangeMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeMember" xlink:label="RangeMember_2" xlink:title="RangeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="RangeAxis" xlink:to="RangeMember_2" xlink:title="definition: RangeAxis to RangeMember_2" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_MinimumMember" xlink:label="MinimumMember" xlink:title="MinimumMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RangeMember" xlink:to="MinimumMember" xlink:title="definition: RangeMember to MinimumMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_MaximumMember" xlink:label="MaximumMember" xlink:title="MaximumMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RangeMember" xlink:to="MaximumMember" xlink:title="definition: RangeMember to MaximumMember" order="2.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/NotesPayableAndAmendedCreditAgreementDetails">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentLineItems" xlink:label="DebtInstrumentLineItems" xlink:title="DebtInstrumentLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentsAbstract" xlink:label="DebtInstrumentsAbstract" xlink:title="DebtInstrumentsAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="DebtInstrumentsAbstract" xlink:title="definition: DebtInstrumentLineItems to DebtInstrumentsAbstract" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity" xlink:label="LineOfCreditFacilityMaximumBorrowingCapacity" xlink:title="LineOfCreditFacilityMaximumBorrowingCapacity" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="LineOfCreditFacilityMaximumBorrowingCapacity" xlink:title="definition: DebtInstrumentLineItems to LineOfCreditFacilityMaximumBorrowingCapacity" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentMaturityDate" xlink:label="DebtInstrumentMaturityDate" xlink:title="DebtInstrumentMaturityDate" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="DebtInstrumentMaturityDate" xlink:title="definition: DebtInstrumentLineItems to DebtInstrumentMaturityDate" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_DebtInstrumentBasisSpreadOnLiborVariableRate" xlink:label="DebtInstrumentBasisSpreadOnLiborVariableRate" xlink:title="DebtInstrumentBasisSpreadOnLiborVariableRate" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="DebtInstrumentBasisSpreadOnLiborVariableRate" xlink:title="definition: DebtInstrumentLineItems to DebtInstrumentBasisSpreadOnLiborVariableRate" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentBasisSpreadOnVariableRate1" xlink:label="DebtInstrumentBasisSpreadOnVariableRate1" xlink:title="DebtInstrumentBasisSpreadOnVariableRate1" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="DebtInstrumentBasisSpreadOnVariableRate1" xlink:title="definition: DebtInstrumentLineItems to DebtInstrumentBasisSpreadOnVariableRate1" order="5.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage" xlink:label="LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage" xlink:title="LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage" xlink:title="definition: DebtInstrumentLineItems to LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage" order="6.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_CashAndNoncashConsiderationWithRespectToAcquisitionAfterAmendement" xlink:label="CashAndNoncashConsiderationWithRespectToAcquisitionAfterAmendement" xlink:title="CashAndNoncashConsiderationWithRespectToAcquisitionAfterAmendement" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="CashAndNoncashConsiderationWithRespectToAcquisitionAfterAmendement" xlink:title="definition: DebtInstrumentLineItems to CashAndNoncashConsiderationWithRespectToAcquisitionAfterAmendement" order="7.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_DividendsCashAfterAmendment" xlink:label="DividendsCashAfterAmendment" xlink:title="DividendsCashAfterAmendment" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="DividendsCashAfterAmendment" xlink:title="definition: DebtInstrumentLineItems to DividendsCashAfterAmendment" order="8.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity" xlink:label="LineOfCreditFacilityRemainingBorrowingCapacity" xlink:title="LineOfCreditFacilityRemainingBorrowingCapacity" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="LineOfCreditFacilityRemainingBorrowingCapacity" xlink:title="definition: DebtInstrumentLineItems to LineOfCreditFacilityRemainingBorrowingCapacity" order="9.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NumberOfBusinessesAcquired" xlink:label="NumberOfBusinessesAcquired" xlink:title="NumberOfBusinessesAcquired" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="NumberOfBusinessesAcquired" xlink:title="definition: DebtInstrumentLineItems to NumberOfBusinessesAcquired" order="10.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentFaceAmount" xlink:label="DebtInstrumentFaceAmount" xlink:title="DebtInstrumentFaceAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="DebtInstrumentFaceAmount" xlink:title="definition: DebtInstrumentLineItems to DebtInstrumentFaceAmount" order="11.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_BusinessAcquisitionNumberOfInstallmentsToPaymentOfPurchaseConsideration" xlink:label="BusinessAcquisitionNumberOfInstallmentsToPaymentOfPurchaseConsideration" xlink:title="BusinessAcquisitionNumberOfInstallmentsToPaymentOfPurchaseConsideration" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="BusinessAcquisitionNumberOfInstallmentsToPaymentOfPurchaseConsideration" xlink:title="definition: DebtInstrumentLineItems to BusinessAcquisitionNumberOfInstallmentsToPaymentOfPurchaseConsideration" order="12.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_BusinessAcquisitionPrincipalInstallmentsPayableAtCostOfAcquiredByEntityAtAccruedInterest" xlink:label="BusinessAcquisitionPrincipalInstallmentsPayableAtCostOfAcquiredByEntityAtAccruedInterest" xlink:title="BusinessAcquisitionPrincipalInstallmentsPayableAtCostOfAcquiredByEntityAtAccruedInterest" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="BusinessAcquisitionPrincipalInstallmentsPayableAtCostOfAcquiredByEntityAtAccruedInterest" xlink:title="definition: DebtInstrumentLineItems to BusinessAcquisitionPrincipalInstallmentsPayableAtCostOfAcquiredByEntityAtAccruedInterest" order="13.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths" xlink:label="LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths" xlink:title="LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths" xlink:title="definition: DebtInstrumentLineItems to LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths" order="14.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo" xlink:label="LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo" xlink:title="LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo" xlink:title="definition: DebtInstrumentLineItems to LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo" order="15.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LineOfCreditFacilityInterestRateDuringPeriod" xlink:label="LineOfCreditFacilityInterestRateDuringPeriod" xlink:title="LineOfCreditFacilityInterestRateDuringPeriod" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="LineOfCreditFacilityInterestRateDuringPeriod" xlink:title="definition: DebtInstrumentLineItems to LineOfCreditFacilityInterestRateDuringPeriod" order="16.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RepaymentsOfDebt" xlink:label="RepaymentsOfDebt" xlink:title="RepaymentsOfDebt" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="RepaymentsOfDebt" xlink:title="definition: DebtInstrumentLineItems to RepaymentsOfDebt" order="17.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentTable" xlink:label="DebtInstrumentTable" xlink:title="DebtInstrumentTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="DebtInstrumentLineItems" xlink:to="DebtInstrumentTable" xlink:title="definition: DebtInstrumentLineItems to DebtInstrumentTable" order="18.0" t1:closed="true" t1:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentAxis" xlink:label="DebtInstrumentAxis" xlink:title="DebtInstrumentAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="DebtInstrumentTable" xlink:to="DebtInstrumentAxis" xlink:title="definition: DebtInstrumentTable to DebtInstrumentAxis" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="DebtInstrumentNameDomain" xlink:title="DebtInstrumentNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="DebtInstrumentAxis" xlink:to="DebtInstrumentNameDomain" xlink:title="definition: DebtInstrumentAxis to DebtInstrumentNameDomain" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="DebtInstrumentNameDomain_2" xlink:title="DebtInstrumentNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="DebtInstrumentAxis" xlink:to="DebtInstrumentNameDomain_2" xlink:title="definition: DebtInstrumentAxis to DebtInstrumentNameDomain_2" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_CreditAgreementMember" xlink:label="CreditAgreementMember" xlink:title="CreditAgreementMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentNameDomain" xlink:to="CreditAgreementMember" xlink:title="definition: DebtInstrumentNameDomain to CreditAgreementMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CreditFacilityAxis" xlink:label="CreditFacilityAxis" xlink:title="CreditFacilityAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="DebtInstrumentTable" xlink:to="CreditFacilityAxis" xlink:title="definition: DebtInstrumentTable to CreditFacilityAxis" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CreditFacilityDomain" xlink:label="CreditFacilityDomain" xlink:title="CreditFacilityDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="CreditFacilityAxis" xlink:to="CreditFacilityDomain" xlink:title="definition: CreditFacilityAxis to CreditFacilityDomain" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CreditFacilityDomain" xlink:label="CreditFacilityDomain_2" xlink:title="CreditFacilityDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="CreditFacilityAxis" xlink:to="CreditFacilityDomain_2" xlink:title="definition: CreditFacilityAxis to CreditFacilityDomain_2" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RevolvingCreditFacilityMember" xlink:label="RevolvingCreditFacilityMember" xlink:title="RevolvingCreditFacilityMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="CreditFacilityDomain" xlink:to="RevolvingCreditFacilityMember" xlink:title="definition: CreditFacilityDomain to RevolvingCreditFacilityMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeAxis" xlink:label="RangeAxis" xlink:title="RangeAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="DebtInstrumentTable" xlink:to="RangeAxis" xlink:title="definition: DebtInstrumentTable to RangeAxis" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeMember" xlink:label="RangeMember" xlink:title="RangeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="RangeAxis" xlink:to="RangeMember" xlink:title="definition: RangeAxis to RangeMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeMember" xlink:label="RangeMember_2" xlink:title="RangeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="RangeAxis" xlink:to="RangeMember_2" xlink:title="definition: RangeAxis to RangeMember_2" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_MinimumMember" xlink:label="MinimumMember" xlink:title="MinimumMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RangeMember" xlink:to="MinimumMember" xlink:title="definition: RangeMember to MinimumMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_MaximumMember" xlink:label="MaximumMember" xlink:title="MaximumMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RangeMember" xlink:to="MaximumMember" xlink:title="definition: RangeMember to MaximumMember" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShortTermDebtTypeAxis" xlink:label="ShortTermDebtTypeAxis" xlink:title="ShortTermDebtTypeAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="DebtInstrumentTable" xlink:to="ShortTermDebtTypeAxis" xlink:title="definition: DebtInstrumentTable to ShortTermDebtTypeAxis" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShortTermDebtTypeDomain" xlink:label="ShortTermDebtTypeDomain" xlink:title="ShortTermDebtTypeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="ShortTermDebtTypeAxis" xlink:to="ShortTermDebtTypeDomain" xlink:title="definition: ShortTermDebtTypeAxis to ShortTermDebtTypeDomain" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShortTermDebtTypeDomain" xlink:label="ShortTermDebtTypeDomain_2" xlink:title="ShortTermDebtTypeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="ShortTermDebtTypeAxis" xlink:to="ShortTermDebtTypeDomain_2" xlink:title="definition: ShortTermDebtTypeAxis to ShortTermDebtTypeDomain_2" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_NotesPayableMember" xlink:label="NotesPayableMember" xlink:title="NotesPayableMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShortTermDebtTypeDomain" xlink:to="NotesPayableMember" xlink:title="definition: ShortTermDebtTypeDomain to NotesPayableMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessAcquisitionAxis" xlink:label="BusinessAcquisitionAxis" xlink:title="BusinessAcquisitionAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="DebtInstrumentTable" xlink:to="BusinessAcquisitionAxis" xlink:title="definition: DebtInstrumentTable to BusinessAcquisitionAxis" order="5.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="BusinessAcquisitionAcquireeDomain" xlink:title="BusinessAcquisitionAcquireeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="BusinessAcquisitionAxis" xlink:to="BusinessAcquisitionAcquireeDomain" xlink:title="definition: BusinessAcquisitionAxis to BusinessAcquisitionAcquireeDomain" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="BusinessAcquisitionAcquireeDomain_2" xlink:title="BusinessAcquisitionAcquireeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="BusinessAcquisitionAxis" xlink:to="BusinessAcquisitionAcquireeDomain_2" xlink:title="definition: BusinessAcquisitionAxis to BusinessAcquisitionAcquireeDomain_2" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_TwoThousandSeventeenAcquisitionMember" xlink:label="TwoThousandSeventeenAcquisitionMember" xlink:title="TwoThousandSeventeenAcquisitionMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionAcquireeDomain" xlink:to="TwoThousandSeventeenAcquisitionMember" xlink:title="definition: BusinessAcquisitionAcquireeDomain to TwoThousandSeventeenAcquisitionMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_TwoThousandEighteenAcquisitionMember" xlink:label="TwoThousandEighteenAcquisitionMember" xlink:title="TwoThousandEighteenAcquisitionMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionAcquireeDomain" xlink:to="TwoThousandEighteenAcquisitionMember" xlink:title="definition: BusinessAcquisitionAcquireeDomain to TwoThousandEighteenAcquisitionMember" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_LeadingProviderOfIndustrialInjuryPreventionMember" xlink:label="LeadingProviderOfIndustrialInjuryPreventionMember" xlink:title="LeadingProviderOfIndustrialInjuryPreventionMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionAcquireeDomain" xlink:to="LeadingProviderOfIndustrialInjuryPreventionMember" xlink:title="definition: BusinessAcquisitionAcquireeDomain to LeadingProviderOfIndustrialInjuryPreventionMember" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementScenarioAxis" xlink:label="StatementScenarioAxis" xlink:title="StatementScenarioAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="DebtInstrumentTable" xlink:to="StatementScenarioAxis" xlink:title="definition: DebtInstrumentTable to StatementScenarioAxis" order="6.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScenarioUnspecifiedDomain" xlink:label="ScenarioUnspecifiedDomain" xlink:title="ScenarioUnspecifiedDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="StatementScenarioAxis" xlink:to="ScenarioUnspecifiedDomain" xlink:title="definition: StatementScenarioAxis to ScenarioUnspecifiedDomain" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScenarioUnspecifiedDomain" xlink:label="ScenarioUnspecifiedDomain_2" xlink:title="ScenarioUnspecifiedDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="StatementScenarioAxis" xlink:to="ScenarioUnspecifiedDomain_2" xlink:title="definition: StatementScenarioAxis to ScenarioUnspecifiedDomain_2" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_AprilTwoThousandNineteenMember" xlink:label="AprilTwoThousandNineteenMember" xlink:title="AprilTwoThousandNineteenMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ScenarioUnspecifiedDomain" xlink:to="AprilTwoThousandNineteenMember" xlink:title="definition: ScenarioUnspecifiedDomain to AprilTwoThousandNineteenMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_AprilTwoThousandTwentyMember" xlink:label="AprilTwoThousandTwentyMember" xlink:title="AprilTwoThousandTwentyMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ScenarioUnspecifiedDomain" xlink:to="AprilTwoThousandTwentyMember" xlink:title="definition: ScenarioUnspecifiedDomain to AprilTwoThousandTwentyMember" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_AugustTwoThousandNineteenMember" xlink:label="AugustTwoThousandNineteenMember" xlink:title="AugustTwoThousandNineteenMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ScenarioUnspecifiedDomain" xlink:to="AugustTwoThousandNineteenMember" xlink:title="definition: ScenarioUnspecifiedDomain to AugustTwoThousandNineteenMember" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_AugustTwoThousandTwentyMember" xlink:label="AugustTwoThousandTwentyMember" xlink:title="AugustTwoThousandTwentyMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ScenarioUnspecifiedDomain" xlink:to="AugustTwoThousandTwentyMember" xlink:title="definition: ScenarioUnspecifiedDomain to AugustTwoThousandTwentyMember" order="4.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/NotesPayableAndAmendedCreditAgreementSummaryOfAggregateAnnualPaymentsOfPrincipalRequiredToRevolvingCreditFacilityDetails" />
  <link:definitionLink xlink:type="extended" xlink:role="http://usph.com/role/CommonStockDetails">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EquityClassOfTreasuryStockLineItems" xlink:label="EquityClassOfTreasuryStockLineItems" xlink:title="EquityClassOfTreasuryStockLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ClassOfStockDisclosuresAbstract" xlink:label="ClassOfStockDisclosuresAbstract" xlink:title="ClassOfStockDisclosuresAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EquityClassOfTreasuryStockLineItems" xlink:to="ClassOfStockDisclosuresAbstract" xlink:title="definition: EquityClassOfTreasuryStockLineItems to ClassOfStockDisclosuresAbstract" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockRepurchaseProgramNumberOfSharesAuthorizedToBeRepurchased" xlink:label="StockRepurchaseProgramNumberOfSharesAuthorizedToBeRepurchased" xlink:title="StockRepurchaseProgramNumberOfSharesAuthorizedToBeRepurchased" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EquityClassOfTreasuryStockLineItems" xlink:to="StockRepurchaseProgramNumberOfSharesAuthorizedToBeRepurchased" xlink:title="definition: EquityClassOfTreasuryStockLineItems to StockRepurchaseProgramNumberOfSharesAuthorizedToBeRepurchased" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_MaximumPercentageOfRepurchaseOfCommonStock" xlink:label="MaximumPercentageOfRepurchaseOfCommonStock" xlink:title="MaximumPercentageOfRepurchaseOfCommonStock" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EquityClassOfTreasuryStockLineItems" xlink:to="MaximumPercentageOfRepurchaseOfCommonStock" xlink:title="definition: EquityClassOfTreasuryStockLineItems to MaximumPercentageOfRepurchaseOfCommonStock" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_BankCreditAgreementToPermitShareRepurchasesOfCommonStock" xlink:label="BankCreditAgreementToPermitShareRepurchasesOfCommonStock" xlink:title="BankCreditAgreementToPermitShareRepurchasesOfCommonStock" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EquityClassOfTreasuryStockLineItems" xlink:to="BankCreditAgreementToPermitShareRepurchasesOfCommonStock" xlink:title="definition: EquityClassOfTreasuryStockLineItems to BankCreditAgreementToPermitShareRepurchasesOfCommonStock" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockRepurchasedDuringPeriodShares" xlink:label="StockRepurchasedDuringPeriodShares" xlink:title="StockRepurchasedDuringPeriodShares" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EquityClassOfTreasuryStockLineItems" xlink:to="StockRepurchasedDuringPeriodShares" xlink:title="definition: EquityClassOfTreasuryStockLineItems to StockRepurchasedDuringPeriodShares" order="5.0" />
    <link:loc xlink:type="locator" xlink:href="usph-20180930.xsd#usph_AdditionalEstimatedRepurchaseOfCommonStock" xlink:label="AdditionalEstimatedRepurchaseOfCommonStock" xlink:title="AdditionalEstimatedRepurchaseOfCommonStock" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EquityClassOfTreasuryStockLineItems" xlink:to="AdditionalEstimatedRepurchaseOfCommonStock" xlink:title="definition: EquityClassOfTreasuryStockLineItems to AdditionalEstimatedRepurchaseOfCommonStock" order="6.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SharesIssuedPricePerShare" xlink:label="SharesIssuedPricePerShare" xlink:title="SharesIssuedPricePerShare" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EquityClassOfTreasuryStockLineItems" xlink:to="SharesIssuedPricePerShare" xlink:title="definition: EquityClassOfTreasuryStockLineItems to SharesIssuedPricePerShare" order="7.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ClassOfTreasuryStockTable" xlink:label="ClassOfTreasuryStockTable" xlink:title="ClassOfTreasuryStockTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="EquityClassOfTreasuryStockLineItems" xlink:to="ClassOfTreasuryStockTable" xlink:title="definition: EquityClassOfTreasuryStockLineItems to ClassOfTreasuryStockTable" order="8.0" t1:closed="true" t1:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeAxis" xlink:label="RangeAxis" xlink:title="RangeAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ClassOfTreasuryStockTable" xlink:to="RangeAxis" xlink:title="definition: ClassOfTreasuryStockTable to RangeAxis" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeMember" xlink:label="RangeMember" xlink:title="RangeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="RangeAxis" xlink:to="RangeMember" xlink:title="definition: RangeAxis to RangeMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeMember" xlink:label="RangeMember_2" xlink:title="RangeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="RangeAxis" xlink:to="RangeMember_2" xlink:title="definition: RangeAxis to RangeMember_2" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_MaximumMember" xlink:label="MaximumMember" xlink:title="MaximumMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RangeMember" xlink:to="MaximumMember" xlink:title="definition: RangeMember to MaximumMember" order="1.0" />
  </link:definitionLink>
</link:linkbase>
