Characteristics of the study sample at baseline. Two-tailed Student t tests are used for differences between means. Chi-square tests are used for percentages. All data presented were from baseline. Values are mean (SD) or percentages unless otherwise specified.
| Characteristics | Knee Pain at Baseline | p | |
|---|---|---|---|
| Absent, n = 441 | Present, n = 439 | ||
| Age, yrs | 62.5 (7.4) | 62.0 (7.5) | 0.29 |
| Female | 48 | 50 | 0.14 |
| Body mass index | 27.1 (4.2) | 28.5 (5.1) | < 0.01 |
| Knee ROA | 58 | 61 | 0.28 |
| Bone marrow lesion | 30 | 42 | < 0.01 |
| Cartilage defect | 47 | 60 | < 0.01 |
| Meniscal lesion | 77 | 81 | 0.11 |
| Effusion synovitis present, any grade ≥ 2 | 50 | 50 | 0.70 |
| Effusion synovitis, n | 0.09 | ||
| Grade 0 | 1 | 2 | |
| Grade 1 | 149 | 142 | |
| Grade 2 | 210 | 181 | |
| Grade 3 | 81 | 114 | |
| Characteristics | Knee Pain Over 2.6 Yrs | p | |
| Improved or Unchanged, n = 610 | New or Worsening, n = 170 | ||
| Effusion synovitis present, any grade ≥ 2 | 78 | 22 | 0.01 |
| Effusion synovitis, n | < 0.01 | ||
| Grade 0 | 1 | 1 | |
| Grade 1 | 214 | 41 | |
| Grade 2 | 273 | 72 | |
| Grade 3 | 122 | 56 | |
Values denoting statistical significance (p at α = 0.05) are in bold face. ROA: radiographic osteoarthritis.