[Importance of the Segond avulsion fracture as a sign of complex ligamentous knee injury].

The Segond fracture is a small bony avulsion of the lateral tibial condyle. A study of 11 patients, treated between 1986 and 1990, points out the importance of this injury. In our series all patients showed an additional major ligamentous damage. 10 patients had an injury of the anterior cruciate ligament. This harmless "lateral capsular sign" on the standard x-ray of the knee-joint should give reason for further diagnostic measures, mainly the arthroscopic examination.