Total hip arthroplasty in patients with coxarthrosis due to developmental dysplasia of the hip: Is fixation of the subtrochanteric osteotomy necessary?

OBJECTIVES: This study aims to analyze the clinical, functional, and radiographic results of patients with Crowe type IV developmental dysplasia of the hip (DDH) sequelae undergoing cementless total hip arthroplasty (THA) with transverse subtrochanteric shortening osteotomy without fixation at the osteotomy site. PATIENTS AND METHODS: Between March 2013 and February 2020, a total of 42 hips of 34 patients (8 males, 26 females; mean age: 50.7±11.7 years; range, 27 to 76 years) with Crowe type IV DDH treated with subtrochanteric shortening osteotomy combined with primary cementless THA were retrospectively analyzed. Each case was evaluated to the Harris Hip Score (HHS). Crowe classification, location of the rotation center of hip, loosening of the implants, and union at the osteotomy line were evaluated radiologically. RESULTS: The mean follow-up was 57.9±31.5 (range, 24 to 192) months. The mean interval to complete bone union in 40 hips (95%) after surgery was 3.5±0.9 (range, 2 to 6) months. The mean preoperative HHS scores of the patients was 35.6±6.86, while the scores increased to 91.53±5.41 at the final follow-up (p<0.001). CONCLUSION: Our study results suggest that excellent clinical and radiological results can be obtained in Crowe type IV dysplastic hips in patients undergoing THA with the rectangular femoral component and transverse shortening osteotomy technique, without fixation at the osteotomy site.