The incidence of clinically significant avascular necrosis (AVN) following medial open reduction of the dislocated hip in children with developmental dysplasia of the hip (DDH) remains unknown. We performed a systematic review of the literature to identify all clinical studies reporting the results of medial open reduction surgery. A total of 14 papers reporting 734 hips met the inclusion criteria. The mean follow-up was 10.9 years (2 to 28). The rate of clinically significant AVN (types 2 to 4) was 20% (149/734). From these papers 221 hips in 174 children had sufficient information to permit more detailed analysis. The rate of AVN increased with the length of follow-up to 24% at skeletal maturity, with type 2 AVN predominating in hips after five years’ follow-up. The presence of AVN resulted in a higher incidence of an unsatisfactory outcome at skeletal maturity (55% vs 20% in hips with no AVN; p < 0.001). A higher rate of AVN was identified when surgery was performed in children aged < 12 months, and when hips were immobilised in ≥ 60°of abduction post-operatively. Multivariate analysis showed that younger age at operation, need for further surgery and post-operative hip abduction of ≥ 60° increased the risk of the development of clinically significant AVN.

Cite this article: Bone Joint J 2014;96-B:279–86.

The Ponseti method of clubfoot management requires a period of bracing in order to maintain correction. This study compared the effectiveness of ankle foot orthoses and Denis Browne boots and bar in the prevention of recurrence following successful initial management. Between 2001 and 2003, 45 children (69 feet) with idiopathic clubfeet achieved full correction following Ponseti casting with or without a tenotomy, of whom 17 (30 clubfeet) were braced with an ankle foot orthosis while 28 (39 clubfeet) were prescribed with Denis Browne boots and bar. The groups were similar in age, gender, number of casts and tenotomy rates. The mean follow-up was 60 months (50 to 72) in the ankle foot orthosis group and 47 months (36 to 60) in the group with boots and bars. Recurrence requiring additional treatment occurred in 25 of 30 (83%) of the ankle foot orthosis group and 12 of 39 (31%) of the group with boots and bars (p < 0.001). Additional procedures included repeat tenotomy (four in the ankle foot orthosis group and five in the group treated with boot and bars), limited posterior release with or without tendon transfers (seven in the ankle foot orthosis group and two in the group treated with boots and bars), posteromedial releases (nine in the orthosis group) and midfoot osteotomies (five in the orthosis group, p < 0.001).

Following initial correction by the Ponseti method, children managed with boots and bars had far fewer recurrences than those managed with ankle foot orthoses. Foot abduction appears to be important to maintain correction of clubfeet treated by the Ponseti method, and this cannot be achieved with an ankle foot orthosis.