Background:Previous studies have shown that the lateral femoral condyle ratio (LFCR) measured by X-ray has a significant relationship with the anterior cruciate ligament (ACL) injury. However, few relevant studies have been performed on LFCR measured by magnetic resonance imaging (MRI).Purpose:(1) To evaluate the relationship between LFCR measured by MRI and ACL injury or rerupture. (2) To compare the LFCR measured by MRI with existing bony morphological risk factors and screen out the most predictive risk factors for primary ACL injury or rerupture.Study Design:Cohort study; Level of evidence, 3.Methods:Totally 147 patients who underwent knee arthroscopic surgery from 2015 to 2019 with minimum follow-up of 48 months were retrospectively evaluated. Patients were placed into three groups: 1) the control group of patients with simple meniscus tears without ligament injury; 2) the primary noncontact ACL injury group; 3) ACL rerupture group (ACL reconstruction failure). The LFCR measured by MRI and other previous known risk factors associated with MRI (notch width index, medial tibial slope, lateral tibial slope, medial tibial depth, lateral tibial height) were performed to evaluate their predictive value for ACL injury and rerupture. All the risk factors with p < 0.01 according to univariate analysis were included in the logistic regression models. Receiver operating characteristic (ROC) curves were analyzed for sensitivity, specificity, cut-off, and area under the curve (AUC). Z tests were used to compare the AUC values.Results:The LFCR measured by MRI was obviously higher in primary ACL injury group (0.628 ± 0.020) and in ACL rerupture group (0.625 ± 0.021) than that in the control group (0.593 ± 0.030). The best risk factor was the LFCR with a cut-off of 0.602 (AUC, 0.818; 95% CI, 0.748–0.878; sensitivity, 90%; specificity, 66%). When combined with lateral tibial slope (cutoff, 7°) and lateral tibial height (cutoff, 3.6 mm), the diagnostic performance was improved significantly (AUC, 0.896; 95% CI, 0.890–0.950; sensitivity, 87%; specificity, 80%).Conclusion:The increased LFCR measured by MRI was associated with a significantly higher risk for ACL injury or rerupture. The combination of LFCR, lateral tibial slope and lateral tibial height were the most predictive risk factors. This may help clinicians identify susceptible individuals and allow precision approaches for better prevention, treatment and management of this disease.

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MRI测量股骨外髁比与前交叉韧带损伤的关系

背景：既往研究表明，X线测量的股骨外侧髁比（LFCR）与前交叉韧带（ACL）损伤有显着关系。然而，目前对磁共振成像(MRI)测量的LFCR进行的相关研究较少。目的：(1)探讨MRI测量的LFCR与ACL损伤或再断裂的关系。 (2)将MRI测量的LFCR与现有骨形态学危险因素进行比较，筛选出最能预测原发ACL损伤或再断裂的危险因素。研究设计：队列研究；证据级别，3。方法：对2015年至2019年接受膝关节镜手术且最短随访时间为48个月的147例患者进行回顾性评估。将患者分为三组：1）对照组，单纯半月板撕裂，无韧带损伤； 2）原发性非接触性ACL损伤组； 3）ACL再断裂组（ACL重建失败）。通过MRI测量的LFCR和其他已知的与MRI相关的危险因素（切迹宽度指数、胫骨内侧坡度、胫骨外侧坡度、胫骨内侧深度、胫骨外侧高度）被用来评估它们对ACL损伤和再断裂的预测价值。所有风险因素p<根据单变量分析，0.01 被纳入逻辑回归模型中。分析受试者工作特征（ROC）曲线的敏感性、特异性、截止值和曲线下面积（AUC）。采用Z检验比较AUC值。结果：MRI测量的LFCR在ACL原发损伤组（0.628±0.020）和ACL再断裂组（0.625±0.021）中均明显高于对照组（0.593±0.030）。 ）。最佳危险因素是 LFCR，截止值为 0.602（AUC，0.818；95% CI，0.748–0.878；敏感性，90%；特异性，66%）。当与胫骨外侧坡度（截止值，7°）和胫骨外侧高度（截止值，3.6 mm）相结合时，诊断性能显着提高（AUC，0.896；95% CI，0.890-0.950；敏感性，87%；特异性，80） %). 结论：MRI 测量的 LFCR 增加与 ACL 损伤或再断裂的风险显着升高相关。 LFCR、胫骨外侧坡度和胫骨外侧高度的组合是最具预测性的危险因素。这可能有助于临床医生识别易感个体，并提供精确的方法来更好地预防、治疗和管理这种疾病。