Abstract
PURPOSE: Non-surgical treatment is indicated in children with severe developmental dysplasia of the hip. Immobilisation may affect motor development. This study assessed motor outcomes in children treated with closed reduction, cast and brace or closed reduction and brace. METHODS: We conducted a retrospective study on 35 children (mean age 2.1 ± 1.4 months) and a prospective study on 17 children (mean age 1.4 ± 0.9 months), involving 68 hips (22 type D, 31 type III and 15 type IV). Treatment duration averaged 4.7 ± 2.2 months in retrospective study and 3.5 ± 1.9 months in prospective study. Multivariate regression analysed predictors of walking age, including treatment type, age at treatment start, developmental dysplasia of the hip severity, family history and breech presentation. A mixed-effects linear model compared treatment duration across studies. p values of z-score tests on regression coefficients are reported. RESULTS: Mean walking age was 14.6 ± 2.6 months in retrospective study and 14.7 ± 2.4 months in prospective study. Dysplasia severity (p < 0.05) and later treatment start (p < 0.001) predicted delayed walking age. Treatment type showed no overall effect; however, in type III, casts significantly delayed walking (p < 0.05). Severity had no impact when treatment began before 2 months, whereas later treatment led to significant differences based on severity (p < 0.01). At the last follow-up of prospective study, at 16 months, no parents reported persistent motor impairments compared with peers. CONCLUSION: Treatment initiated within 2 months mitigates the effect of developmental dysplasia of the hip severity on motor development, resulting in similar walking outcomes across severities. These results underscore the importance of early treatment in severe developmental dysplasia of the hip. LEVEL OF EVIDENCE: II.