Do Schatzker type II and III tibial plateau fractures require simultaneous medial collateral ligament repair? A retrospective cohort study

Few studies have focused on the correlation between Schatzker type II and III tibial plateau fractures (TPFs) and medial collateral ligament (MCL) injuries that require surgical exploration and repair. Therefore, we designed this study to evaluate the relationship between lateral plateau collapse and the likelihood of requiring MCL surgical repair, without relying on MRI. We hypothesized that more severe lateral plateau collapse is associated with a higher probability of MCL injury warranting operative treatment. We conducted a retrospective analysis of clinical data from patients with Schatzker type II and III tibial plateau fractures (TPFs) who underwent open reduction and internal fixation (ORIF) between July 2022 and December 2023. Of the 165 eligible patients, 31(18.8%) underwent concurrent MCL repair and 134(81.2%) did not.​ The vertical distance between the lowest point of the medial and lateral platforms and the line connecting the medial and lateral condyles of the femur and their ratio ( r -value) were statistically analyzed. Receiver operating characteristic(ROC) curves were used to investigate the diagnostic performance of the r -value for predicting the need for surgical MCL repair. The optimal critical threshold was determined by maximizing the Youden index. The degree of lateral plateau collapse was positively correlated with the likelihood of undergoing MCL repair. The area under the ROC curve was 0.911. The maximum Youden index was 0.737, corresponding to an optimal r -value cutoff of 0.402, which can be used as a critical threshold to identify patients at high risk of requiring surgical MCL repair. More severe lateral tibial plateau collapse is associated with a greater risk of MCL injury requiring surgical intervention. An r -value of less than 0.402 on standard anteroposterior knee radiographs indicates a high suspicion of surgically relevant MCL rupture and warrants consideration for intraoperative exploration and repair. Level III, retrospective cohort study.