Diffuse Pigmented Villonodular Synovitis as a Rare Cause of Graft Failure Following Anterior Cruciate Ligament Reconstruction.

This case report describes a 42-year-old woman who was diagnosed with pigmented villonodular synovitis (PVNS) in the knee. The patient had received a bone-patella tendon-bone autograft reconstruction of her anterior cruciate ligament (ACL) 22 years prior to her diagnosis of PVNS. After a traumatic event that tore her ACL graft, she underwent a second surgery to repair the initial reconstruction. However, her pain and joint instability remained unresolved. When radiolucent lesions in her tibia and femur were identified through a radiographic image, the patient was referred to the authors' orthopedic oncology clinic. Additional imaging, including magnetic resonance imaging, revealed PVNS, and she was scheduled for debridement and a complete synovectomy of the knee. After surgery, the patient's pain decreased dramatically. She continues to maintain an active lifestyle despite a relatively minor decrease in range of motion. In this case, PVNS proved to be an unlikely complication after ACL reconstruction. The patient remains at risk for the development of degenerative arthritis. [Orthopedics. 2018; 41(1):e142-e144.].