To the editor: A 67-year-old man presented with left hip pain for the last one week. On detailed questioning, he declared that he had been under chemotherapy for prostate cancer for one year. His medical/family history was otherwise unremarkable. On physical examination, he had pain and mild limitation in his left hip joint. Radiographs demonstrated slight joint space narrowing and sclerosis, consistent with osteoarthritis. Laboratory tests including erythrocyte sedimentation rate and C-reactive protein were normal. No evidence of infection or inflammatory arthropathies was detected. He was given a non-steroidal anti-inflammatory drug. On the second visit (3 months later), he needed to use a wheelchair. His complaints got worse and he could not walk. There was no history of trauma. Radiographs revealed severe collapse and destruction of the femoral head. The patient was consulted to the urology department; and as he was not considered to have any metastasis, he underwent hip arthroplasty.

Edited by CUI Yi