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  <xs:element id="si_SoftwareLicensingAgreementMember" abstract="true" name="SoftwareLicensingAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="si_SoftwareLicensingAgreementUpfrontPaymentMember" abstract="true" name="SoftwareLicensingAgreementUpfrontPaymentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="si_SoftwareLicensingAgreementIncrementalPaymentsMember" abstract="true" name="SoftwareLicensingAgreementIncrementalPaymentsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="si_ConsultingAgreementMember" abstract="true" name="ConsultingAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="si_RMDSupplyAgreementMember" abstract="true" name="RMDSupplyAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="si_ShoulderInnovationsInc.Member" abstract="true" name="ShoulderInnovationsInc.Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="si_GenesisInvestmentHoldingsLLCMember" abstract="true" name="GenesisInvestmentHoldingsLLCMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="si_CultivateMDCapitalAcceleratorFundL.P.Member" abstract="true" name="CultivateMDCapitalAcceleratorFundL.P.Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="si_RelatedPartyTransactionAgreementTerm" abstract="false" name="RelatedPartyTransactionAgreementTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="si_RelatedPartyTransactionRoyaltiesPercentOfNetSalesPrice" abstract="false" name="RelatedPartyTransactionRoyaltiesPercentOfNetSalesPrice" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="si_SeriesSeedWarrantsMember" abstract="true" name="SeriesSeedWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="si_SeriesBWarrantsMember" abstract="true" name="SeriesBWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="si_TemporaryEquityCommitmentAmount" abstract="false" name="TemporaryEquityCommitmentAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="si_TemporaryEquityNumberOfClosingTranches" abstract="false" name="TemporaryEquityNumberOfClosingTranches" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="si_TemporaryEquityStockIssuedDuringPeriodSharesWarrantsExercised" abstract="false" name="TemporaryEquityStockIssuedDuringPeriodSharesWarrantsExercised" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="si_TemporaryEquityStockIssuedDuringPeriodShareWarrantsExercised" abstract="false" name="TemporaryEquityStockIssuedDuringPeriodShareWarrantsExercised" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="si_TemporaryEquityStockIssuedDuringPeriodSharesNewIssues" abstract="false" name="TemporaryEquityStockIssuedDuringPeriodSharesNewIssues" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="si_TemporaryEquitySharesConversionOfConvertibleSecurities" abstract="false" name="TemporaryEquitySharesConversionOfConvertibleSecurities" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="si_CommonOptionsMember" abstract="true" name="CommonOptionsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="si_CommonWarrantsMember" abstract="true" name="CommonWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="si_SeriesDWarrantsMember" abstract="true" name="SeriesDWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="si_ReportableSegmentMember" abstract="true" name="ReportableSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="si_MedicalEducationExpense" abstract="false" name="MedicalEducationExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="si_ConvertibleNotesSeptember2028MaturityMember" abstract="true" name="ConvertibleNotesSeptember2028MaturityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="si_TrinityLoanAgreementMember" abstract="true" name="TrinityLoanAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="si_DebtInstrumentConvertibleThresholdAmount" abstract="false" name="DebtInstrumentConvertibleThresholdAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="si_DebtInstrumentConvertibleThresholdAmountMinimum" abstract="false" name="DebtInstrumentConvertibleThresholdAmountMinimum" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="si_DebtInstrumentConvertibleLiquidationPreferencePaymentMultiplier" abstract="false" name="DebtInstrumentConvertibleLiquidationPreferencePaymentMultiplier" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:decimalItemType"/>
  <xs:element id="si_DebtInstrumentInterestRateFloor" abstract="false" name="DebtInstrumentInterestRateFloor" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
</xs:schema>
