Correction of the acetabular index is more crucial than the type of acetabuloplasty in developmental dysplasia

BackgroundAcetabular remodeling may not be predictable after open reduction in developmental dysplasia of the hip (DDH) in older children. Several acetabuloplasties have been developed, and all are aimed at correcting the dysplastic acetabulum. The goal of this study is to evaluate if the type of pelvic acetabuloplasty and the corrected (postoperative) acetabular index (AI) affect early follow-up femoral head coverage.MethodsA retrospective review of single-surgeon consecutive acetabuloplasties (Dega or Pemberton) from December 2012 to December 2015 was conducted. The inclusion criteria were a diagnosis of DDH, undergoing simultaneous primary open reduction, and follow-up of at least 18 months. Univariable analysis was based on the type of acetabuloplasty. The correlation between AI and final center edge angle (CEA) was tested. Multiple regression was performed.ResultsOf the total 58 hips in 39 patients included, 41 underwent Dega acetabuloplasty, and 17 had Pemberton acetabuloplasty. The median follow-up was 40.50 months (interquartile range 27.25-57). Pemberton acetabuloplasty produced a lower corrected AI, but the difference was not significant in follow-up measurements. Corrected AI was significantly correlated with final CEA (R=-0.31, P=0.018). In the multiple regression, only corrected AI was independently associated with final CEA (B=-0.29, SE=0.15, P=0.06), whereas the type of acetabuloplasty, age, and preoperative severity of the dislocation were not.ConclusionThe correction obtained during acetabuloplasty affects early follow-up femoral head coverage. Ensuring proper sizing and placement of the grafted bone is probably more important than the type of acetabuloplasty chosen.Level of evidenceLevel III.