Cross-sectional associations between a history of knee injury or surgery and MRI abnormalities
| Outcome variables | History of knee injury | History of knee surgery | ||
| Univariate | Multivariable† | Univariate | Multivariable† | |
| RR (95% CI) | RR (95% CI) | RR (95% CI) | RR (95% CI) | |
| BMLs | 1.41 (0.99 to 2.02) | 1.30 (0.87 to 1.96) | 1.49 (1.03 to 2.15) | 1.29 (0.64 to 2.59) |
| Cartilage defects* | 1.27 (0.75 to 2.17) | 1.23 (0.70 to 2.17) | 3.47 (2.28 to 5.27) | 3.80 (2.40 to 6.01) |
| Meniscal tears/extrusion | 6.45 (1.57 to 26.62) | 6.50 (1.59 to 26.49) | 8.92 (3.41 to 23.32) | 14.25 (6.38 to 31.80) |
| Effusion synovitis* | 1.41 (0.98 to 2.01) | 1.47 (1.03 to 2.09) | 1.54 (1.01 to 2.35) | 1.68 (0.97 to 2.91) |
| Univariate β (95% CI) | Multivariable† β (95% CI) | Univariate β (95% CI) | Multivariable† β (95% CI) | |
| Synovial fluid volume (mL) | 1.25 (0.28 to 2.22) | 1.02 (0.17 to 1.88) | 2.50 (0.27 to 4.74) | 1.85 (−0.35 to 4.05) |
| Synovial membrane thickness (mm) | −0.01 (−0.09 to 0.08) | −0.01 (−0.10 to 0.08) | 0.04 (−0.04 to 0.12) | 0.03 (−0.06 to 0.12) |
MRI abnormalities are the outcomes in these analyses.
RR represents the risk of having an MRI abnormality present in those who had a previous knee injury or surgery.
Boldface denotes statistically significant result.
β coefficient represents the difference in synovial fluid volume (mL) and synovial membrane thickness (mm) in those who did and did not report a previous knee injury or surgery.
*Defined as grade 2 or higher.
†Adjusted for age, weight and height.