Isolated posterior cruciate ligament injury: literature review and case reports.

A review of the recent literature on posterior cruciate ligament injury reveals few descriptions of isolated injury. The major findings in this injury include abrasions over the anterior tibial surface, presence of a posterior drawer sign, recurvatum of the knee, bloody effusion, and X-ray evidence of avulsion of the posterior tibial margin. The mechanism of injury appears to be a direct blow to the anterior tibial surface with the knee acutely flexed and the posterior capsule lax. The force of the blow drives the tibia posterior, thereby causing a tension injury to the posterior cruciate ligament while actually increasing the laxity in the posterior capsule. All injuries were treated surgically through a posterior approach using internal fixation of the avulsion fracture. Satisfactory wound and fracture healing occurred in all cases and function at 3 months was good with ligamentous stability present.