Slope of the Medial Tibial Plateau and the Incidence of a Medial Meniscal Tear

Objectives: Previous studies of the association between tibial slope and meniscal tear have led to contradictory results. In this regard, the present study aimed to examine the effect of medial tibial plateau slope on the incidence of isolated medial meniscal tear.Methods: This study was performed on 75 patients with a posterior horn medial meniscal tear and 150 matched control subjects. Two different observers evaluated the slope of the medial tibial plateau on the lateral radiographs. Reliability of radiographic evaluation was investigated in a pilot study using the intraclass correlation coefficient (ICC) test.Results: Intra-observer reliability for the slope of the medial tibial plateau was high, with ICC values of 0.961 and 0.957 for the first and second observers, respectively. The interobserver reliability was 0.947. The mean slope was 10.2±3.7° in the case group and 10.1±4.4° in the control group (P=0.97). Moreover, the mean slopes of the medial tibial plateau were 10.3±4.1º and 10.1±4.2º in participants with tibial bone varus angles of (TBVA) 4º and ≥ 4.2 (P=0.77). The slope was not statistically correlated with age (r=0.074, 95% CI: -0.05−0.20, P=0.26), gender (r=0.07, P=0.29), BMI (r=0.02, 95% CI: -0.10−0.15, P=0.74), level of joint degeneration (r=-0.023, 95% CI: -0.11−0.15, P=0.73), and TBVA (r=-0.010, 95% CI: -0.14−0.12; P=0.12).Conclusion: No significant difference was found between patients with and without an isolated meniscal tear in terms of the medial tibial plateau slope. These results suggest that the tibial slope may not affect the incidence of isolated medial meniscal tears.