Posterolateral corner injuries in association with anterior cruciate ligament ruptured knees: a MRI analysis

BACKGROUND: The posterolateral corner (PLC) injury of the knee was one of the important factors leading to the failure of anterior cruciate ligament (ACL) reconstruction. We aimed to investigate the incidence and risk factors of the PLC injuries in association with ACL ruptured knees. METHODS: From January 2013 to September 2017, the magnetic resonance (MR) images of the patients with acute ACL torn were analyzed. Patients with injuries of the PLC, lateral and medial meniscus, medial collate ligament, and posterior cruciate ligament were recorded. RESULTS: A total of 145 MR images of knees with ACL ruptured were included in this study. The incidence of combined PLC with ACL injuries was 22.07%. There were 24.82% patients with other injuries complicated with ACL injuries except PLC injuries. There was no correlation of PLC injuries with different sexes and different affected knees, as well as the injuries of the medial or lateral meniscus, medial collate ligament, and posterior cruciate ligament. CONCLUSIONS: The PLC injury is common and dependent in association with ACL rupture. It is helpful to avoid failure of ACL reconstruction when the injuries are treated timely.