Diagnosis of posterior cruciate ligament (PCL) tears

Despite numerous clinical tests that have been described for diagnosing posterior cruciate ligament (PCL) insufficiency, the diagnosis of acute and chronic injuries is often missed at initial evaluation. The posterior drawer test and the posterior sag test (Godfrey test) are considered the most sensitive tests for diagnosing PCL insufficiency. However, objective clinical quantification of posterior laxity by physical examination remains difficult. To improve diagnostic accuracy stress radiography has been introduced, which overcomes some of the limitations seen with clinical examination and arthrometer testing. With tibial displacement values >12 mm, injury to peripheral structures, particularly the posterolateral corner structures, has to be considered. While magnetic resonance imaging (MRI) is a useful adjunct in the acute PCL injury its findings should not be used to infer functional status in chronic cases.