Knee dislocation following anterior cruciate ligament disruption without any other ligament tears.

We report a rare case of complete knee dislocation following anterior cruciate ligament (ACL) disruption without any other ligament tears. The pathology of the knee joint was torn ACL, intact other ligaments, osteochondral fractures and bone bruise of the lateral femoral condyle, and torn lateral meniscus. In this case, osteochondral fracture resulting from the anteriorly sublaxiation of the tibia following ACL disruption was considered to prevent from spontaneous reduction. This case suggests that anterolateral knee dislocation and spontaneous reduction may occur in ACL injuries.