Table 1.
Characteristics of Medicare beneficiaries receiving primary and revision TKA between 1991 and 2010
| Primary TKA | Revision TKA | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 1991–1994 | 1995–1998 | 1999–2002 | 2003–2006 | 2007–2010 | 1991–1994 | 1995–1998 | 1999–2002 | 2003–2006 | 2007–2010 | |
| Characteristics | ||||||||||
| No. of hospitalizations | 431050 | 530128 | 578614 | 816497 | 915562 | 44120 | 57785 | 65197 | 76526 | 74935 |
| Age, mean(SD), y | 73.8 (5.8) | 74.5 (5.9) | 74.7 (5.9) | 74.7 (5.9) | 74.2 (6.2) | 74.2 (5.9) | 75.2 (6.1) | 75.4 (6.2) | 75.3 (6.3) | 74.8 (6.5) |
| Sex, female | 283353 (65.7) | 346827 (65.4) | 379650 (65.6) | 535181 (65.5) | 592777 (64.7) | 26772 (60.7) | 35062 (60.7) | 38948 (59.7) | 44654 (58.4) | 43535 (58.1) |
| Race | ||||||||||
| White | 389996 (90.5) | 487200 (91.9) | 529078 (91.4) | 744882 (91.2) | 831082 (90.8) | 39850 (90.3) | 52787 (91.4) | 58781 (90.2) | 68770 (89.9) | 66981 (89.4) |
| Black | 21515 (5.0) | 28685 (5.4) | 30563 (5.3) | 42442 (5.2) | 49477 (5.4) | 2531 (5.7) | 3704 (6.4) | 4606 (7.1) | 5413 (7.1) | 5581 (7.4) |
| Other | 7376 (1.7) | 10774 (2.0) | 16654 (2.9) | 25908 (3.2) | 32195 (3.5) | 622 (1.4) | 975 (1.7) | 1586 (2.4) | 2078 (2.7) | 2158 (2.9) |
| Missing | 12163 (2.8) | 3469 (0.7) | 2314 (0.4) | 3265 (0.4) | 2808 (0.3) | 1117 (2.5) | 319 (0.6) | 224 (0.3) | 265 (0.3) | 215 (0.3) |
| Comorbidity | ||||||||||
| Diabetes | 45158 (10.5) | 69141 (13.0) | 89230 (15.4) | 152877 (18.7) | 198241 (21.7) | 4863 (11.0) | 8660 (15.0) | 11638 (17.9) | 16358 (21.4) | 18129 (24.2) |
| CHF | 14732 (3.4) | 22041 (4.2) | 24940 (4.3) | 37622 (4.6) | 35652 (3.9) | 2173 (4.9) | 3966 (6.9) | 5147 (7.9) | 6909 (9.0) | 5893 (7.9) |
| Obesity | 17092 (4.0) | 27415 (5.2) | 35684 (6.2) | 67120 (8.2) | 105251 (11.5) | 1619 (3.7) | 2906 (5.0) | 3956 (6.1) | 6115 (8.0) | 7555 (10.1) |
| Renal failure | 1742 (0.4) | 2383 (0.4) | 3443 (0.6) | 12531 (1.5) | 37335 (4.1) | 330 (0.7) | 556 (1.0) | 950 (1.5) | 2525 (3.3) | 5088 (6.8) |
| Number of comorbid conditions, mean (SD) | 1.2 (1.2) | 1.4 (1.3) | 1.6 (1.3) | 1.9 (1.4) | 2.1 (1.4) | 1.2 (1.2) | 1.6 (1.4) | 1.8 (1.4) | 2.2 (1.5) | 2.3 (1.5) |
Abbreviation: SD, standard deviation
P values (test for trend) are less than 0.001 for all comparisons except age (primary TKA, P=0.56; revision TKA, P=0.46).
All values are presented as No. (%) unless otherwise indicated.
The race category of Other includes Asian, Hispanic, North American Native, or other not-specified individuals.