| STOCK-BASED COMPENSATION | 7. STOCK-BASED COMPENSATION Compensation costs related to share-based payments for the three months ended September 30, 2011 and October 1, 2010 totaled $1.8 million and $2.4 million, respectively. Of these amounts $1.5 million and $2.1 million, respectively, are included in Selling, General and Administrative Expenses. Compensation costs related to share-based payments for the nine months ended September 30, 2011 and October 1, 2010 totaled $5.1 million and $5.2 million, respectively. Of these amounts $4.2 million and $4.5 million, respectively, are included in Selling, General and Administrative Expenses. During the third quarter of 2010, the Company recorded $0.7 million of additional expense related to the accelerated vesting of equity awards issued to the Company's former Senior Vice President – Orthopaedics, who passed away during the quarter. Stock-based compensation expense included in the Condensed Consolidated Statement of Cash Flows includes costs recognized for the annual share contribution to the Company's 401(k) plan of $1.2 million and $0.0 million for the three months ended September 30, 2011 and October 1, 2010, respectively. Stock-based compensation expense included in the Condensed Consolidated Statement of Cash Flows for the annual share contribution to the Company's 401(k) plan for the nine months ended September 30, 2011 and October 1, 2010 totaled $3.7 million and $0.0 million, respectively. The weighted average fair value and assumptions used to value options granted are as follows: | | | Nine Months Ended | | | | September 30, | | | October 1, | | | | 2011 | | | 2010 | | | Weighted average fair value | $ | 9.42 | | $ | 8.24 | | | Risk-free interest rate | | 2.04% | | | 2.62% | | | Expected volatility | | 40% | | | 40% | | | Expected life (in years) | | 5 | | | 5 | | | Expected dividend yield | | 0% | | | 0% |
| | The following table summarizes time-vested stock option activity: | | | | | | | | Number of Time-Vested Stock Options | | | Weighted Average Exercise Price | | | Weighted Average Remaining Contractual Life (In Years) | | | Aggregate Intrinsic Value (In Millions) | | | Outstanding at | December 31, 2010 | | 1,463,556 | | $ | 23.46 | | | | | | | | | | Granted | | 292,959 | | | 24.15 | | | | | | | | | | Exercised | | (78,028) | | | 21.41 | | | | | | | | | | Forfeited or expired | | (101,901) | | | 22.55 | | | | | | | | | Outstanding at | September 30, 2011 | | 1,576,586 | | $ | 23.75 | | | 6.3 | | $ | 0.4 | | | Exercisable at | September 30, 2011 | | 1,055,286 | | $ | 23.51 | | | 5.2 | | $ | 0.4 |
| | The following table summarizes performance-vested stock option activity: | | | | | | | | Number of Performance-Vested Stock Options | | | Weighted Average Exercise Price | | | Weighted Average Remaining Contractual Life (In Years) | | | Aggregate Intrinsic Value (In Millions) | | | Outstanding at | December 31, 2010 | | 744,523 | | $ | 23.68 | | | | | | | | | | Exercised | | (25,194) | | | 22.56 | | | | | | | | | | Forfeited or expired | | (235,977) | | | 22.22 | | | | | | | | | Outstanding at | September 30, 2011 | | 483,352 | | $ | 24.45 | | | 6.2 | | $ | 0.0 | | | Exercisable at | September 30, 2011 | | 252,894 | | $ | 22.55 | | | 5.2 | | $ | 0.0 |
| | The following table summarizes time-vested restricted stock and unit activity: | | | | | | | | Time-Vested Activity | | | Weighted Average Fair Value | | | Nonvested at | December 31, 2010 | | 123,386 | | $ | 22.57 | | | | Granted | | 25,241 | | | 24.16 | | | | Vested | | (7,993) | | | 21.98 | | | | Forfeited or expired | | (2,713) | | | 23.23 | | | Nonvested at | September 30, 2011 | | 137,921 | | $ | 22.88 |
| | The following table summarizes performance-vested restricted stock and unit activity: | | | | | | | | Performance-Vested Activity | | | Weighted Average Fair Value | | | Nonvested at | December 31, 2010 | | 283,797 | | $ | 15.10 | | | | Granted | | 279,415 | | | 18.21 | | | | Vested | | (200) | | | 18.47 | | | | Forfeited or expired | | (11,394) | | | 16.11 | | | Nonvested at | September 30, 2011 | | 551,618 | | $ | 16.67 |
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