LFCI and knee morphological parameters as a risk factor in anterior cruciate ligament tear on magnetic resonance imaging- A case control analysis

The anterior cruciate ligament is commonly injured and multiple risk factors have been studied. But there is paucity of articles considering predictive risk factors of femoral condyle morphology in south Indian population. This study aims to assess distal femoral condyle sphericity as a risk factor in anterior cruciate ligament injury and to correlate it with proximal tibia morphological risk factors. This is a case control study including 80 patients with knee MRI aged between 18 and 60.They were grouped into cases (40) and controls (40). Cases being non-contact ACL injuries without multi ligamentous injuries and controls being MRI with ACL intact. Lateral femoral condyle index, posterior tibial slope, medial and lateral tibial depth were measured and compared. The risk factors were analysed with multiple logistic regression. The lateral femoral condyle index had a mean value of 0.79 with standard deviation of ± 0.05 in cases group. Control group had a mean value of 0.803 with standard deviation of ± 0.05. Medial tibial slope in cases (8°) was lesser than in control group (7.6°). Lateral tibial slope was found to more among cases group (9.1°) than in control group (7.5°). Medial tibial depth had a mean of 4.07 mm among cases and 3.9 mm among control group. There was a moderate positive correlation between LFCI and Medial Tibial slope among cases that was statistically significant (P = 0.002). In addition, there was a weak negative correlation between LCFI and Medial Tibial Depth that was statistically significant. The lateral femoral condyle index was not found to be significant statistically among ACL injured patients. In our study we concluded that lateral tibial slope was more reliable risk factor in predicting ACL injury when compared to other parameters.