Table 2.
Baseline characteristics according to previous surgery yes/no (all primary TKAs). Values are count (%) unless otherwise specified
| Previous surgery |
|||
|---|---|---|---|
| yes | no | ||
| n = 844 | n = 3,101 | ||
| Factor | (21%) | (79%) | p-value |
| Women | 439 (52) | 2,233 (72) | < 0.001 |
| Age at operation | |||
| mean (SD) | 67.3 (9.3) | 72.5 (9.2) | < 0.001 |
| BMI, mean (SD)a | 29 (5.1) | 30 (5.7) | < 0.001 |
| BMI categories | |||
| < 24.9 | 206 (24) | 578 (19) | |
| 25–29.9 | 321 (38) | 1,106 (36) | |
| 30–34.9 | 227 (27) | 829 (27) | |
| ≥ 35 | 89 (11) | 572 (19) | |
| ASA score 3–4b | 158 (19) | 879 (28) | < 0.001 |
| Ever smokerc | 740 (35) | 286 (24) | < 0.001 |
| Bilateral primary TKA | 88 (10) | 625 (20) | < 0.001 |
| Diagnosis primary OA | 545 (65) | 2,848 (92) | < 0.001 |
| Previous knee surgery | |||
| Arthroscopy | 127 (15) | – | |
| Meniscectomy | 400 (47) | – | |
| Osteosynthesis | 75 (9) | – | |
| Osteotomy | 129 (15) | – | |
| Ligamentoplasty | 43 (5) | – | |
| Other | 70 (8) | – | |
| Implant-related information | |||
| Patellar resurfacing, yes | 527 (62) | 2,135 (69) | < 0.001 |
| Posterior-stabilized, yes | 677 (80) | 2,496 (81) | 0.9 |
| Fixed-bearing, yes | 780 (92) | 2,974 (96) | < 0.001 |
| Surgery duration, min (SD) | 124 (31) | 119 (28) | < 0.001 |
a
BMI was missing in 17 cases (0.4%).
b
ASA score was missing in 4 cases (0.1%).
c
Smoking status was missing in 73 cases (1.9%).