Pigmented villonodular synovitis of the elbow with rdial,median and ulnar nerve compression

Pigmented villonodular synovitis (PVNS) is a rare, idiopathic proliferative disorder of the synovium. While, PVNS of elbow is extremely rare. We report an 82-year-old female patient with 20-year-history of gradually increased PVNS in her left elbow. The multiple masses were located in anterior, medial and lateral of elbow. Her radial, median and ulnar nerves were compressed by the tumor. We resected tumor of extra-articular part piecemeally and released the compression of nerves. After the surgery, the patient gained a functional recovery. Two years after surgery she had a tumor recurrence, but without any symptoms of nerve compression syndromes. We discussed its clinical diagnosis, radiological features, MRI findings, pathophysiology, and treatment.