Pigmented Villonodular Synovitis of the Glenohumeral Joint and Biceps Tendon Sheath.

A 34-year-old woman presented with paroxysmal, insidious shoulder pain with effusion. MRI demonstrated a permeative, intermediate-signal lesion on T1 and T2 sequences involving the glenohumeral joint and biceps tendon sheath. The patient was treated with arthroscopic synovectomy, debridement, and subpectoral biceps tenodesis, with histopathology demonstrating pigmented villonodular synovitis (PVNS). PVNS is an extremely rare lesion of the glenohumeral joint and surrounding extra-articular structures. Awareness of this condition is paramount for timely diagnosis and intervention before joint destruction occurs. Arthroscopic treatment with meticulous attention to surgical technique is a feasible treatment strategy in the absence of end-stage chondral damage.