Large Tenosynovial Giant Cell Tumor Treated with Hip Arthroscopy in the Setting of Osteoarthritis: 13-Year Outcomes with Annual MRI Surveillance: A Case Report.

CASE: A 21-year-old man presented with a ∼1.5-year history of atraumatic left hip pain and imaging suspicious for a diffuse tenosynovial giant cell tumor (TSGCT) with signs of osteoarthritis. Hip arthroscopy for tumor debulking and treatment of associated pathology were recommended given his age and activity level. TSGCT diagnosis was confirmed, and the patient has remained pain and tumor free per annual magnetic resonance imaging with excellent functional outcomes 13 years postoperatively.

CONCLUSION: Hip arthroscopy can aid in diagnosing and treating young patients with severe TSGC tumors of the hip, even in the presence of osteoarthritic changes. Preoperative patient counseling is critical to set expectations.