Table III. —Relative risk of knee pain between different tertiles of knee loading in 24 months.
| Knee loading | Tertiles | Range in each tertile | Total knees | Risk of any knee pain | Risk of frequent knee pain | ||||
|---|---|---|---|---|---|---|---|---|---|
| Knees with any pain * | RR (95% CI) ** |
P value |
Knees with frequent pain * | RR (95% CI) ** |
P value | ||||
| KAM (Nm/kg) |
Low (reference) | ≤0.596 | 93 | 15 (16.1%) | 1.00 | - | 6 (6.5%) |
1.00 | - |
| Medium | 0.597-0.722 | 92 | 21 (22.8%) | 1.69 (0.76, 3.79) |
0.201 | 10 (10.9%) |
2.33 (0.73, 7.45) |
0.152 | |
| High | ≥0.723 | 91 | 25 (27.5%) | 2.48 (0.99, 6.20) |
0.053 | 13 (14.3%) |
3.82 (0.96, 15.1) |
0.057 | |
| KFM (Nm/kg) |
Low (reference) | ≤0.175 | 92 | 24 (26.1%) | 1.00 | - | 15 (16.3%) |
1.00 | - |
| Medium | 0.176-0.383 | 94 | 21 (22.3%) | 0.79 (0.36, 1.72) |
0.555 | 9 (9.6%) |
0.50 (0.17, 1.43) |
0.196 | |
| High | ≥0.384 | 90 | 16 (17.8%) | 0.57 (0.24, 1.33) |
0.194 | 5 (5.6%) |
0.25 (0.08, 0.85) | 0.027 | |
*Number (%) of knees; **controlling for age, gender, body height, comorbidities, activity level, and walking speed. KAM: peak knee adduction moment; KFM: peak knee flexion moment; RR: adjusted relative risk; 95% CI: 95% confidence interval of RR.