Tubercular arthritis presenting as osteonecrosis of the femoral head: A case report.

A tuberculosis hip that presents as osteonecrosis of the femoral head is an extremely rare condition. There are no previous reports of this condition, and there is no consensus on the method of total hip arthroplasty for this group of patients. We present a case of a 72-year-old man who had clinical gradual hip pain in both hips for 1 year. He was diagnosed with post-collapsed osteonecrosis of the femoral head in both hips and was scheduled for total hip arthroplasty of the left hip. During his clinical follow-up, he suddenly experienced excruciating acute pain. Investigation to rule out infection was positive for only C-reactive proteins, but his synovial fluid work-up was negative. An intraoperative finding revealed that there was collapse of the femoral head with eroded acetabular cartilage and rice body-like synovitis. Total hip arthroplasty was performed, and the tissue was sent for diagnosis. Tissue acid-fast bacilli were positive, so the patient received anti-tuberculosis drugs for 9 months, with no recurrent infection. Tuberculosis arthritis presenting as osteonecrosis of the femoral head is a complex condition that is difficult to diagnose due to the radiographic pictures of femoral head collapse and arthritic change being similar in both diseases. Acute pain onset with rapid collapse of the femoral head should be a consideration or suspect for this infectious condition. Hence, investigation to rule out infection is important. Anti-tuberculosis drugs are the standard treatment for early or advanced arthritis, and one-stage or two-stage total hip arthroplasty is the choice of treatment for advanced arthritis.