[Secondary synovial chondromatosis of the ankle joint].

Synovial chondromatosis of the ankle is a rare condition, particularly secondary chondromatosis. In view of a possible traumatic pathogenesis, chondromatosis should be kept in mind in daily trauma and orthopedics practice. Diagnostic imaging gives a first indication. The key to differentiating between the primary and secondary forms is histological identification. This case shows the necessity of exact differentiation, even in cases of a causal link with a specific injury.