Adherence to Wide-Abduction Brace Treatment is Associated With Improved Hip Abduction and Radiographic Outcomes in Legg-Calvé-Perthes Disease.

Introduction: The wide-abduction A-frame brace contains the femoral head to improve its remodeling in Legg-Calvé-Perthes disease (LCPD). There is no study of the effect of brace adherence on hip outcomes. The purpose of this study was to determine if patient adherence to A-frame brace treatment is associated with improved hip abduction range of motion and radiographic outcomes in children with LCPD.

Methods: This retrospective study included patients aged 4 to 11 years with LCPD treated with an A-frame brace. Patients aged >11 and those treated with osteotomy before completing brace treatment were excluded. Built-in temperature sensors measured brace wear. Hip abduction was measured on examination before and after bracing. Deformity index (DI) and sphericity deviation score (SDS) were measured from radiographs at the 2-year follow-up and healed stage, respectively. Pearson correlation and multiple regression analyses were performed.

Results: Fifty-seven patients (44 male; 77%) were included with a mean age of 7.0±1.6 at brace treatment and mean adherence of 0.66±0.28. Brace adherence was associated with increased hip abduction ( R =0.36; P =0.006) and decreased DI ( R =-0.37; P =0.042) across all patients, and decreased SDS in patients <9 years old at the time of brace treatment ( R =-0.58; P =0.024). A +0.50 increase in adherence was associated with +9.4° hip abduction ( P =0.018), -0.13 DI ( P =0.027), and -17.7 SDS ( P =0.019).

Conclusions: Adherence to A-frame brace treatment was associated with increased hip abduction, decreased femoral head deformity, and increased sphericity. Patients and parents can be counseled regarding brace adherence to maximize outcomes of treatment.

Level of evidence: III-Therapeutic Study.