Detection of tears of the posterior cruciate ligament (PCL) with MRI is usually based on the appearance of the ligament. However, other MRI findings may be useful in establishing the diagnosis. We assessed these associated injuries in the cases of complete tears of the PCL, reviewing MRls. We evaluated 26 patients who received PCL reconstruction with complete tear of posterior cruciate ligament from Feb 1995 to May 1997 retrospectively. We studied associated findings with PCL injuries. Anterior tibial plateau lesions were found in 15 of 26 cases (57.7%). Meniscal injuries were found in 8 of 26 cases (30.8%). Popliteus muscular injuries was found in 7 of 26 cases (26.9%). Capsular injuries were found in 2 of 26 cases (7.7%). Retinacular injury which has never been described in PCL injuries, was found in 7 cases (26.9%, P>0.05), Other ligamentous injuries were associated in 22 of 26 cases (84.6%). Medial collateral ligament injuries were found in 16 of 22 (61.5%, P<0.05) cases. The frequency of associated ligamentous injury and meniscal tear correlated well with results reported by other authors. The presence and location of bone contusions and fractures correlated with the mechanisms of injury; the anterior tibial plateau was the most commonly affected site. We concluded that the associated injuries were very helpful in diagnosing PCL injuries with MRI.