Clinical and radiologic evaluation of the posterior cruciate ligament-injured knee

Accurate isolated PCL diagnosis continues to present a challenge. This article reviews the current literature regarding clinical and radiographic evaluation of PCL injuries.

A thorough history to understand the mechanism of injury should begin any evaluation. Several clinical tests have been shown to effectively assess PCL laxity, with the posterior drawer test possessing the highest sensitivity and specificity. Any thorough exam should compare the contralateral, uninjured leg. If a PCL or multi-ligament injury is suspected, plain radiographs should be performed to avoid missing a fracture or avulsion. An MRI represents the current gold standard for diagnosing ligament injuries in the knee and should always be obtained in these cases. Due to the significant incidence of nerve injuries (25%) and vascular injuries (18%) with knee dislocations, any suspicion of neurovascular compromise necessitates further studies.

A combination of a thorough clinical history and examination, followed by appropriate imaging optimizes PCL and multi-ligament injury evaluation.