The Early Outcome Of the Bernese Periacetabular Osteotomy For Hip Dysplasia In Multiple Epiphyseal Dysplasia

Abstract Background:Multiple epiphyseal dysplasia (MED) is a rare congenital bone dysplasia. Patients with MED develop secondary hip osteoarthritis as early as third to the fourth decade. Currently, there is no consensus on how to prevent or slow the process of secondary hip osteoarthritis.The Bernese periacetabular osteotomy is a joint preserving surgery to reshape acetabulum and extend coverage for the hip, however, there is no established evidence of the effectiveness for the MED hips.Patients and methods:A retrospective series of 6 hips in 3 patients with multiple epiphyseal dysplasia treated with the Bernese periacetabular osteotomy were reviewed. The average age at the time of surgery was 14.3 years (range: 11.4 to 17.2 y). Radiographic parameters were analyzed preoperatively and 1-year postoperatively. The hip function was evaluated by the Harris Hip Score (HHS) before and after surgery. Results:The mean follow-up time was 1.7 years. The mean LCEA increased from 3.8° to 47.1° (p = .02), ACEA increased from 7.3° to 35.1° (p = .02), and AI decreased from 27.8° to 14.6° (p=.04). The femoral head coverage ratio increased from 66.8% to 100% (p= .02). The procedure achieved femoral head medialization by decreasing central head distance from 86.7mm preoperatively to 82.7mm postoperatively, however, without statistical significance. (p = .699). The improvement of clinical outcomes by mean HHS was significant from 67.3 preoperatively to 86.7 postoperatively (p=0.05).Conclusion:Bernese PAO is a feasible option for treatment of the hip problems in MED patients. It reshapes acetabular and femoral morphology 3-dimensionally. In our study, the short-term follow-up results showed obvious functional and radiographic improvement. A long-term follow-up is necessary in the future.