Incomplete avulsion of the femoral attachment of the posterior cruciate ligament with an osteochondral fragment in a twelve-year-old boy.

Isolated avulsion of the posterior cruciate ligament from the femoral attachment of the knee as a hyperextension injury is rare. We saw a young child with an incomplete avulsion of the posterior cruciate ligament that occurred after a blow to the anterior tibial surface of a flexed knee; the child revealed a lack of knee extension due to a pinch of the osteochondral fragment connected to the anterior band of the posterior cruciate ligament in the knee joint. Arthroscopic extirpation of a fragment was undertaken.