DIFFICULTIeS OF TOTAL HIP REPLACEMENT IN PATIENTS WITH ANKYLOSING SPONDYLITIS (case report)

A distinctive feature of patients with ankylosing spondylitis is the formation of hip ankylosis in an extremely unfavorable functional position combined with upset of sagittal balance of the body along with a thoracolumbar kyphosis. Treatment of these patients poses considerable technical difficulties and is often associated with complications. The authors report a clinical case of a female 40 years old patient with confirmed rhizomelic spondylitis. The patient mainly complained of fixed malposition of the right lower extremity (hip ankylosis in extreme 1450 flexion and 1500 abduction) combined with a severe fixed spine deformity (thoracic kyphosis 920, lumbar lordosis 170). Considering significant sagittal balance disorder it was decided to go for a two-stage procedure. Total hip arthroplasty of the right joint was performed at the first stage. At the second stage the authors corrected thoracolumbar spinal deformity by Th12 (type PSO 4) and L2 (type PSO 3) wedge resections and converging resected vertebral bodies by a multilevel fixation system with transpedicular support elements. The interval between the stages was 11 months. Two-stage treatment of this patient al-lowed to avoid adverse postoperative complications and to achieve a significant functional improvement in one year after treatment started. The sum of points before and after the treat-ment amounted respectively to 46 and 79 on Harris Hip Score, 17 and 38 points on Oxford Hip Score (OHS). To summarize, comprehensive treatment with planning of all subsequent steps prior to hip replacement is the method of choice for avoidance of postoperative complications in patients with ankylosing spondylitis accompanied by a significant upset of sagittal balance.