A tenosynovial giant cell tumor arising from femoral attachment of the anterior cruciate ligament.

The localized type of tenosynovial giant cell tumor usually occurs on the palmar side of fingers and toes. Tenosynovial giant cell tumors of the tendon sheath are rarely intra-articular. We report a giant cell tumor of the tendon sheath arising from femoral attachment of the anterior cruciate ligament and its treatment with arthroscopy in a 28-year-old man.