Pigmented villonodular synovitis on lumbar spine : a case report and literature review.

Pigmented villonodular synovitis (PVNS) is a benign proliferative joint disease with an uncertain etiology that uncommonly involves the spine. We present a case of PVNS involving the lumbar spine. A 38-year-old male developed back pain and pain in both legs caused by a mass in the L4 region of the right lamina. After gross total tumor removal, the symptoms improved. The pathological finding was synovial hyperplasia with accumulation of hemosiderin-laden macrophages. He was diagnosed with PVNS and experienced no recurrence for up to 2 years after surgery. In this report, we review the previous literature and discuss etiology, clinical manifestations, diagnosis, and treatment.