A Unique Presentation of Bilateral Posterolateral Corner Injury With Right Posterior Cruciate Ligament and Left Anterior Cruciate Ligament Tears

Bilateral posterolateral corner (PLC) injuries of the knees are exceptionally rare, particularly when associated with asymmetric cruciate ligament involvement. This case report presents a 23-year-old man who sustained simultaneous bilateral PLC injuries with a right posterior cruciate ligament (PCL) tear and left anterior cruciate ligament (ACL) tear following a single trauma, during a stampede. Initial examination revealed bilateral varus instability with positive dial tests. Magnetic resonance imaging (MRI) confirmed combined PLC and cruciate ligament injuries with associated fibular collateral ligament (FCL) avulsion and popliteus tendon (PLT) tears bilaterally, as well as a lateral meniscus root tear on the right knee. Surgical management was performed sequentially. The right knee underwent open PLC avulsion repair using suture anchors and augmented with an ipsilateral semitendinosus graft (Larson procedure), followed by delayed arthroscopic PCL reconstruction with a peroneus longus graft and lateral meniscus root repair. The left knee was treated with single-stage arthroscopic ACL reconstruction using a quadruple semitendinosus graft, combined with PLC repair augmented using the gracilis tendon and the repair of the avulsed biceps femoris tendon. Postoperative rehabilitation involved staged progression from immobilization to the full range of motion and weight-bearing at 8-12 weeks. At one-year follow-up, the patient achieved right knee motion from 0° to 120° and left knee motion from 0° to 140°, with full ambulation and minimal residual laxity (grade 1 posterior drawer on the right; grade 1a Lachman on the left). This case highlights the clinical importance of the early diagnosis and selective augmented repair of avulsion-type PLC injuries. When combined with timely cruciate ligament reconstruction, such an approach may yield outcomes comparable to formal reconstruction while preserving native tissue and reducing postoperative morbidity in acute multiligamentous knee injuries.