Giant Cell Tumor of the Distal Femur.

A 24-year-old woman presented to a physical therapy clinic reporting a 4-month history of constant left knee pain of insidious onset. In the setting of nonlocalized, nontraumatic chronic knee pain, the physical therapist ordered radiographs, which revealed an osteolytic lesion along the distal anterolateral femur, suggesting a giant cell tumor. The radiologist then recommended computed tomography for better appreciation of the lesion and magnetic resonance imaging to investigate any soft tissue abnormality.