Osteocondromatosis sinovial extraarticular secundaria con afectación de pierna, tobillo y pie. Un caso excepcional./ Osteocondromatosis sinovial extraarticular secundaria con afectación de pierna, tobillo y pie. Un caso excepcional./ Secondary Extra-Articular Synovial Osteochondromatosis with Involvement of the Leg, Ankle and Foot. An Exceptional Case.

Extraarticular synovial osteochondromatosis is a very rare benign disease whose aetiology may be primary or secondary to pre-existing pathology or after trauma. The diagnosis can be made with plain radiography and CT, and MRI is necessary to evaluate the non-mineralized soft tissue component and assess extension. It must be confirmed with a pathological study by biopsy or resection. There is up to a 5% chance of malignant transformation. The treatment of choice for the extensive extra-articular form is surgery by open resection. The case presented illustrates an atypical form of secondary extraarticular OCS with multiple involvement of the leg, ankle and foot.