Table 3.
Risk of radiographic progression by sex-specific extensor torque, stratified by sex and knee alignment
| Medial compartment |
Lateral compartment |
|||||
|---|---|---|---|---|---|---|
| Torque group | Progressors (%) a | Crude RR | Adjusted b RR | Progressors (%) a | Crude RR | Adjusted b RR |
| Women | ||||||
| Neutral alignment | ||||||
| Low | 92 (33) | 1.23 (0.93–1.62) | 0.97 (0.71–1.32) | 92 (37) | 1.45 (1.08–1.94) | 1.34 (1.04–1.84) |
| Middle | 102 (36) | 1.23 (0.94–1.60) | 1.09 (0.83–1.44) | 87 (34) | 1.23 (0.92–1.65) 1.18 (0.87–1.60) | |
| High | 86 (31) | 1.00 | 1.00 | 73 (29) | 1.00 | 1.00 |
| Valgus alignment c | ||||||
| Low | 17 (32) | 0.89 (0.46–1.72) | 0.69 (0.33–1.44) | 48 (37) | 0.99 (0.73–1.35) | 0.85 (0.61, 1.17) |
| Middle | 21 (40) | 1.12 (0.62–2.01) | 0.99 (0.55–1.79) | 43 (33) | 0.90 (0.67–1.24) | 0.87 (0.63–1.20) |
| High | 15 (28) | 1.00 | 1.00 | 38 (29) | 1.00 | 1.00 |
| Varus alignment c | ||||||
| Low | 50 (36) | 1.31 (0.94–1.84) | 1.18 (0.83–1.68) | 20 (29) | 1.10 (0.59–2.07) | 0.92 (0.46–1.84) |
| Middle | 44 (32) | 1.18 (0.83–1.67) | 1.18 (0.84–1.66) | 28 (40) | 1.57 (0.93–2.65) | 1.45 (0.84–2.52) |
| High | 44 (32) | 1.00 | 1.00 | 21 (30) | 1.00 | 1.00 |
| Men | ||||||
| Neutral alignment | ||||||
| Low | 44 (35) | 1.02 (0.70–1.49) | 0.97 (0.63–1.49) | 48 (36) | 1.11 (0.76–1.62) | 1.07 (0.71–1.62) |
| Middle | 42 (34) | 1.08 (0.75–1.54) | 1.08 (0.75–1.55) | 45 (34) | 1.15 (0.79–1.68) | 1.12 (0.77–1.64) |
| High | 39 (31) | 1.00 | 1.00 | 39 (30) | 1.00 | 1.00 |
| Valgus alignment c | ||||||
| Low | 1 (12) | NA | NA | 5 (33) | NA | NA |
| Middle | 6 (76) | NA | NA | 7 (46) | NA | NA |
| High | 1 (12) | NA | NA | 3 (20) | NA | NA |
| Varus alignment c | ||||||
| Low | 105 (34) | 1.26 (0.96–1.58) | 1.04 (0.82–1.32) | 46 (28) | 0.90 (0.62–1.31) 0.88 (0.60–1.30) | |
| Middle | 100 (33) | 1.06 (0.84–1.34) | 0.92 (0.72–1.16) | 56 (34) | 0.97 (0.68–1.36) 0.94 (0.65–1.34) | |
| High | 101 (33) | 1.00 | 1.00 | 62 (38) | 1.00 | 1.00 |
RR: relative risk; CI: 95% confidence interval.
aPercentage indicates progressors in the alignment category.
bAdjusted for baseline Kellgren–Lawrence grade, baseline WOMAC pain, age, body mass index, and alignment.
cVarus and valgus alignment defined as a variation ≥2° in either direction.