The diagnosis of ankylosing spondylitis is often delayed due to ambiguous clinical manifestations and strict diagnostic criteria. However, imaging techniques such as magnetic resonance imaging have been found effective for the early diagnosis of non-radiographic sacroiliitis. New tumor necrosis factor alpha (TNF-α) inhibitors have good efficacy for patients with persistently high disease activity despite conventional nonsteroidal anti-inflammatory drug treatment. Thus, early diagnosis and aggressive treatments are essential for ankylosing spondylitis patients. Because many patients complain of musculoskeletal pains, especially around the sacroiliac joint area, hip specialists should be informed of up-to-date knowledge. In this review, we discuss new diagnostic criteria for ankylosing spondylitis, administration methods of TNF-αinhibitors, and the long-term follow-up results for patients treated with TNF-αinhibitors.

Purpose: This study was performed to evaluate long-term clinical and radiologic outcomes of cemented total hip arthroplasty in patients with ankylosing spondylitis.
Materials and Methods: A retrospective study of 12 patients (16 cases) diagnosed with ankylosing spondylitis undergoing total hip arthroplasty with cemented femoral stem from November 2002 to January 2006 with a minimum follow up of 10 years. Clinical outcomes were assessed using Harris Hip Scores and measures of pain and range of motion. Radiologic outcomes were assessed with serial plain X-ray. Fixation and stability of implant, enthesopathy of ischium and development of heterotopic ossification were also evaluated.
Results: Mean Harris Hip Scores significantly improved from pre-operative levels (58 points; range, 39-81 points) to post-operative (92 points; range, 68-100 points). Mean flexion contracture levels decreased from pre-operative (13°) to post-operative (5°), and mean post-operative range of motion improved 106°compared to pre-operative levels. No newly developed osteolysis lesions or implant loosening were observed in last follow up X-rays. One heterotopic ossification and one greater trochanter fracture were observed. Greater trochanter fracture was treated conservatively, and was resulted in bony union. No patients underwent revisions.
Conclusion: This study revealed positive long-term clinical and radiologic outcomes following total hip arthroplasty with cemented femoral stems in patients with ankylosing spondylitis patients.