Pigmented Villonodular Synovitis Around the Elbow Joint That Required Upper Arm Amputation.

Pigmented villonodular synovitis (PVNS) is a relatively rare benign proliferative disorder of the synovium, and it commonly occurs in the knee joint. A unique case of huge PVNS originating around the elbow joint that required upper arm amputation is reported. A 74-year-old woman had a 5-month history of right elbow pain and noticed a mass measuring 8 × 5 cm on the olecranon side. She had a past history of undergoing tumor resection and flap surgery 9 years earlier, diagnosed as a giant cell tumor involving the right elbow region. She had chronic renal failure, with a shunt on the right forearm. On magnetic resonance imaging, the tumor around the elbow joint showed low signal intensity on T1-weighted images and low to high intensity on T2-weighted images. It was thought that it was difficult to preserve the limb because of the size of the tumor and the shunt blood vessel. Therefore, upper arm amputation was performed. The histological diagnosis was PVNS. There was no recurrence of PVNS postoperatively. In the treatment of PVNS, initial surgery with complete resection of the synovial membrane and careful postoperative follow-up are considered important.