Characteristics of study population at baseline (n = 163).
| Variables | Total Cohort | No Quadriceps Weakness, n = 143.5 | Quadriceps Weakness, n = 19.5 | p* |
|---|---|---|---|---|
| Age, yrs, mean (SD) | 57.7 (10.1) | 56.8 (9.9) | 64.1 (9.5) | 0.003 |
| Women | 88.1 (54.0) | 72.6 (50.6) | 15.5 (79.4) | 0.017 |
| BMI, kg/m2, mean (SD) | 26.1 (4.2) | 26.1 (4.3) | 25.5 (3.4) | 0.543 |
| WOMAC pain (0–100), mean (SD) | 19.6 (16.8) | 17.9 (15.2) | 32.4 (21.5) | 0.009 |
| MRI cartilage score ≥ 2 | 123.6 (75.9) | 106.6 (74.3) | 17.0 (87.6) | 0.196 |
| Medial TF MRI cartilage score ≥ 2 | 88.4 (54.2) | 75.7 (52.7) | 12.7 (65.2) | 0.299 |
| Lateral TF MRI cartilage score ≥ 2 | 52.5 (32.2) | 46.2 (32.2) | 6.3 (32.4) | 0.983 |
| PF MRI cartilage score ≥ 2 | 92.6 (56.8) | 77.2 (53.8) | 15.3 (78.9) | 0.036 |
| KL grade 0 | 65.0 (39.9) | 61.5 (42.8) | 3.6 (18.4) | |
| KL grade 1 | 33.8 (20.7) | 27.2 (19.0) | 6.5 (33.6) | |
| KL grade 2 | 34.5 (21.2) | 31.2 (21.8) | 3.3 (16.8) | 0.036 |
| KL grade 3 | 16.3 (10.0) | 14.7 (10.2) | 1.6 (8.4) | |
| KL grade 4 | 13.4 (8.2) | 9.0 (6.2) | 4.4 (22.7) | |
| KL grade ≥ 2 | 64.2 (39.4) | 54.9 (38.2) | 9.3 (48.0) | 0.409 |
Values are n (%) unless otherwise specified. Stratum-sampling weights were used, hence n = weighted counts which are non-integer.
↵* From a chi-square test (categorical) or a 2-sample t test (continuous). WOMAC: Western Ontario and McMaster Universities Osteoarthritis Index; TF: tibiofemoral; PF: patellofemoral; KL: Kellgren-Lawrence; MRI: magnetic resonance imaging; BMI: body mass index.