An avulsion fracture of the anterior cruciate ligament attachment to the lateral femoral condyle in an elderly patient: a rare finding.

An anterior cruciate ligament (ACL) rupture is a common injury. The ACL usually tears in its mid-substance, an avulsion fracture of the ACL mostly occurs at the tibial attachment. In few cases, an avulsion fracture occurs proximally from the ACL attachment to the lateral femoral condyle. This is a rare finding, especially in elderly patients. We report a case of an avulsion fracture of the ACL attachment to the lateral femoral condyle after a traumatic injury in a 60-year-old female. Injury was not recognized during initial assessment, but was later detected during knee arthroscopy because of persisting mechanical complaints with catching of the knee. This emphasizes the importance of a thorough physical examination and magnetic resonance imaging. As rare as this condition is, it is important for the orthopaedic surgeon in treating these patients to include femoral end avulsion injuries of the ACL in the differential diagnosis.