Dega pelvic osteotomy: indications, results and complications

PURPOSE: Developmental dysplasia of the hip (DDH) after walking age is difficult to treat. Dega pelvic osteotomy is combined with open reduction and femoral osteotomy to obtain concentric stable reduction with good coverage of the femoral head. The purpose of this study is to evaluate the use of the Dega osteotomy in the treatment of DDH in two different age groups. METHODS: A total of 45 patients (52 hips) with a mean age of 3.9 years (1.2 to 12.8) were treated with open reduction, Dega osteotomy and femoral osteotomy. There were 38 dislocated and 14 subluxated hips. Bilateral DDH was observed in seven female patients. Radiographic parameters included acetabular index, centre-edge angle of Wiberg and migration percentage. The final radiographic outcome was evaluated according to the Severin classification. RESULTS: The mean follow-up period was four years (3 to 9). According to the Severin criteria 78.8% were types I or II whereas 21.2% showed types III or IV. There was no statistically significant difference in final outcome between children less than three years of age and older children at the time of surgery. One hip in children with unilateral involvement had developed coxa magna, that interfered with hip concentricity. Three hips (5.8%) showed avascular necrosis of the femoral head. CONCLUSION: Dega osteotomy is a safe and adequate procedure for the management of developmental dysplasia of the hip in walking patients with low complication rates. Restoring the acetabulum to normal or nearly normal can result in good medium-term results. LEVEL OF EVIDENCE: III