Localized Pigmented Villonodular Synovitis Originating from the Lateral Meniscus in a 17-year-old: Case Report and Literature Review of Meniscal-Associated Localized PVNS.

Tenosynovial giant cell tumors (TSGCT) are benign tumors originating from the synovial joint, bursa, or tendon sheath. Localized pigmented villonodular synovitis (PVNS), a subtype of TSGCT, commonly affects the hands and feet and has also been reported in the literature in the knee joint. There is sparse literature on localized PVNS arising specifically from meniscal tissue. We present a case report of a 17-year- old male with symptoms and MRI findings consistent with a lateral meniscus tear. Intraoperatively, the patient was found to have a mass originating from the torn meniscal tissue, which was confirmed by pathology to be a TSGCT. We performed a literature review of intra-articular localized PVNS within the knee presenting as a meniscal tear.