INTRAARTICULAR ABNORMALITIES IN ASSOCIATION WITH POSTERIOR CRUCIATE LIGAMENT INJURIES

The effect of an isolated injury of the posterior cruciate ligament on the articular cartilage and menisci has not been extensively studied. Intraarticular abnormalities in 88 arthroscopically proven posterior cruciate ligament tears in symptomatic patients with straight unidirec tional posterior instability were reviewed. There were 33 patients wit h acute injuries (range, 3 to 21 days; mean, 14) and 55 patients with chronic tears (range, 28 to 3650 days; mean, 786). Of the acute injuri es, chondral defects occurred in 4 patients (12%) and meniscal tears i n 9 patients (27%; 6 lateral and 3 medial). Chondral defects of both t he lateral femoral condyles and patella were present in all 4 patients . Of the chronic injuries, chondral defects occurred in 27 (49%) and m eniscal tears in 20 patients (36%) (7 lateral and 17 medial). Chondral defects of the medial femoral condyle were most common. The mechanism of injury resulting in an isolated injury of the posterior cruciate l igament is most likely to affect the lateral compartment or the articu lar cartilage of the patella. The incidence of articular defects and t he incidence of meniscal tears increased in patients with chronic post erior cruciate ligament injuries; both lesions increased most in the m edial compartment.