Large bursa formation associated with osteochondroma of the scapula: a case report and review of the literature.

Bursitis or large bursa formation associated with osteochondroma has rarely been reported. A 33-year-old male presented with upper back pain, a rapidly developing mass beside the lateral border of his right scapula and snapping elicited by movement of the scapula. Plain radiograms and CT revealed osteochondroma on the ventral surface of the scapula without any unmineralized component and a huge cystic lesion around the osteochondroma. Aspiration of the cystic lesion showed the presence of sero-sanguineous fluid. MRI following the aspiration showed a thin cartilaginous cap with distinct outer margin and no soft tissue mass around the cap. Pathological examinations confirmed the diagnosis of osteochondroma with the large bursa formation. Clinical examination 19 months postoperatively showed an uneventful clinical course.