O1074: Does Brace Treatment Improve Acetabular Dysplasia or Reduce the Rate of Secondary Surgery Following Open Reduction of Developmental Dysplasia of the Hip?

Background: Abduction bracing is commonly used following open reduction and spica casting of developmental dysplasia of the hip (DDH) . However, there is little scientific evidence to support or refute this practice that imposes daily burden and restriction on parents and patients to maintain use of the brace. The purpose of this study was to determine the efficacy of abduction bracing after open reduction in improving the acetabular dysplasia, as measured by acetabular index (AI), and reducing the rate of secondary surgery for residual dysplasia.

Methods: We performed a retrospective review of patients treated with open reductions for DDH at a single tertiary referral center from 1981-2017. Demographic data was obtained including severity of dislocation based on International Hip Dysplasia Institute (IHDI) classification, age at reduction, and casting duration. Patients were prescribed no bracing, part-time (less than 18 hours/day), or full-time (greater than 20 hours/day) bracing based on surgeon preference. Acetabular index (AI) measurements were obtained upon cast removal and from 2- and 4-year follow-up radiographs. Uni-/multivariate analyses were performed.

Results: 183 hips underwent open reduction; 34% by medial and 66% by anterior approach. Overall, 49.2% (90/183) of the hips were treated with abduction bracing. There was no difference between the braced vs. non-braced cohorts with regards to sex (p=0.60), severity of dislocation (p=0.22), or immediate post-casting AI (p=0.67). However, the braced cohort had a younger age at reduction than the non-braced cohort (1.01±0.69 vs 1.37±0.83 years, p=0.002) and slightly longer duration of casting than the non-braced cohort (11.5±2.9 vs 10.6±2.6 weeks, p=0.01). Two-year follow up X-rays showed no difference in AI between the braced vs. non-braced hips (30.6±6.7° vs 28.8±8.5°, p=0.13). Furthermore, no difference in AI was observed at 4 years (25.2±6.6° vs 23.2±7.9°, p=0.10). When categorized by full-time, part-time, or no bracing, no differences in AI were observed at 2 and 4 years follow up (p=0.17 and 0.21). Multivariate analysis demonstrated that neither IHDI classification, abduction bracing, nor age at reduction predicted residual dysplasia at 2- or 4-years post reduction. There was no difference in the rate of secondary surgery for residual dysplasia between braced vs. non-braced hips (34% vs 28%, p=0.34).

Conclusion: Abduction bracing following open reduction for DDH is not associated with decreased residual dysplasia at 2-/4-years post-reduction or with decreased secondary surgery. These results indicate that there may not be any clinical value in bracing after open reduction and casting for DDH. A prospective study is necessary to provide more definitive recommendations.