1034 Radiological Outcomes Following Surgery for Developmental Dysplasia of the Hip

Abstract

Aim Developmental dysplasia of the hip (DDH) is a condition affecting newborns, in which abnormal acetabulum development can result in femoral head subluxation or dislocation. This study aims to retrospectively evaluate radiological outcomes of patients with DDH, treated by either closed reduction, open reduction, or open reduction with osteotomy. Method This study included 59 hips of 54 patients with a median age of 19.6 months at the time of surgery. Radiographs were assessed for the International Hip Dysplasia Institute (IHDI) grade of dislocation, acetabular index (AI), centre-edge angle (CEA), Severin classification and avascular necrosis (AVN). Results Median duration of follow up between primary operation and latest available radiograph was 4.9 years. Pre-operatively, 41 hips were IHDI Grade IV, 16 hips were Grade III and two hips were Grade II. Mean pre-operative AI was 37.9°, which decreased to 22.7° at the latest follow up. Mean CEA was 22.9°. 25 hips were found to be Severin class I, eight hips were class II and three hips were class III. Four hips developed Group II AVN and one hip developed Group III. Nine hips required further surgery. Conclusions The study found overall favourable radiological outcomes of treatment of DDH, with minimal differences between each operation. Longer follow up is needed to evaluate time-dependent outcomes such as Severin class and AVN. A patient-reported outcome questionnaire is necessary to provide information on the correlation of radiological outcomes and physical function.