Background and objectives: Closed reduction and short leg spica casting are the preferred treatment options for children with developmental dysplasia of the hip. This study aimed to show the efficacy behind a standardized closed reduction for managing patients with developmental dysplasia of the hip with concomitant soft tissue releases when indicated and using a short leg plaster of Paris cast to maintain reduction and reporting mid-term results.

Methods: A case series of 95 hips in 84 children aged 6-18 months who had closed reduction, with five years follow up or until next operation, involved in this study. The protocol defines acceptable concentric reduction criteria and the indications for an associated soft tissue release. All the patients were immobilized in a short leg cast for three months. Multiple follow-up radiographs were taken to assess Tönnis grade, Severin grade, acetabular index, and osteonecrosis signs.

Results: A total of 48 hips were Tönnis grade 3/4 hips. At one year, 15 reductions couldn’t be maintained, and these patients needed open reduction. Of these 15 failed reductions, 7 patients were Severin 1; others were Severin 2. Of the 80 successful closed reductions, 70 hips were Severin 1. Surgical management for residual dysplasia was offered for 8 hips. Osteonecrosis was seen in 23 hips but was transient in 20. Bilateral hip dislocations and most Tönnis 4 hips were more likely to fail. Two children had severe osteonecrosis.

Conclusions: Closed reduction, with subsequent adductor and psoas releases, when indicated and using a short leg plaster of Paris cast for three months, brings about good mid-term results in children with developmental dysplasia of the hip aged 6-18 months.

Keywords: Developmental dysplasia of the hip, closed hip reduction, open psoas release, short leg cast.