[A case of psoriatic arthritis associated with ankylosing spondylitis treated with bilateral total hip arthroplasty].

We report a case of a 40-year-old male with psoriatic arthritis associated with ankylosing spondylitis. At the age of 34, the patient suffered pain in his hips, knees, ankles, neck and low back 3 years after the onset of psoriasis vulgaris. The hip pain gradually became severe despite the medical treatment and physical therapy. On admission, the skin lesion of diffuse erythematous plaques with scales was observed on the trunk and extremities. Motion of the spine was markedly limited. We also noted limitation of motion in the bilateral hips and remarkable gait disturbance. In laboratory findings, rheumatoid factor and HLA-B 27 antigen were negative. Radiographs of the cervical spine showed typical bamboo spine as seen in ankylosing spondylitis. Obliteration of the sacroiliac joints and joint space narrowing in the hips with reactive sclerosis were revealed on the pelvic film. Bilateral cementless total hip arthroplasty with adductor tenotomy resulted in complete pain relief and a marked improvement in gait function 18 months after surgery. The appropriate reconstructive surgery was extremely helpful to increase daily activities of the patient in this case.