Outcomes of bilateral developmental dysplasia of the hip after a two-stage procedure of open reduction and Salter osteotomy

Abstract

Objective To evaluate the outcomes of patients with bilateral developmental dysplasia of the hip undergoing a two-stage procedure of open reduction and Salter osteotomy with associated femoral shortening. Methods For this retrospective descriptive study, 19 patients with bilateral developmental dysplasia of the hip (38 hips) were analyzed between January 2012 and January 2015. The procedures consisted of open reduction of the hip, Salter osteotomy, shortening and derotational osteotomy of proximal femur in a two-stage procedure. After cetabular index was measured at pre-operation, one day postoperatively and late postoperatively, they were classified into two group based on operative age: group age 3.5 years. McKay and Severin criteria were used for assessing the function and radiographic results of the hip. And the incidence rate of osteonecrosis and asymmetrical outcome was analyzed. Results All patients were available at the final follow-up. The average follow-up period was 2.8 (2.0 to 5.0) years. The average of acetabular index at preoperatively was 37.4°±4.8°, the average of acetabular index at one day postoperatively 21.3°±3.5°and the average of acetabular index at late postoperatively 16.4°±3.9°According to the McKay criteria at final follow-up, 27 hips (71.1%) had excellent (13 hips) and good (14 hips) clinical results. According to the Severin criteria, 35 hips (92.1%) had excellent (21 hips) and good (14 hips) radiographic results. If the patients were reclassified by age at time of operation, the rate of excellent and good in group aged 3.5 years with 30%; according to the McKay criteria (P=0.001), the of excellent and good in group aged 3.5 years was 92.8% and 90% respectively. No significant differences existed between them according to the Severin criteria (P=0.100). And the incidence of osteonecrosis and asymmetrical outcome were 28.9% and 47.3% respectively. Conclusions Open reduction and Salter osteotomy with associated femoral shortening in a two-stage procedure are both safe and effective for bilateral developmental dysplasia of the hip. It can achieve excellent or good clinical and radiographic results, age 3.5 years. Asymmetrical outcome is a special complication. Additional studies with longer follow-ups are necessary for determining the sustained efficacy of this procedure. Key words: Dislocation of hip joint; Pelvis; Osteotomy