Effects of hip brace on coxa valga in nonambulatory children with cerebral palsy: A randomized controlled trial

Abstract

Background: Coxa valga, measured as the neck-shaft angle (NSA) or head-shaft angle (HSA), is regarded as a potential risk factor for hip dislocation in patients with cerebral palsy. We investigated the effects of a novel hip brace on coxa valga. Methods: A prospective, multicenter, assessor-blinded, randomized controlled trial was conducted from July 2019 to November 2021. Children with cerebral palsy aged 1 to 10 years with Gross Motor Function Classification System levels IV and V were recruited. The study group wore a hip brace for at least 12 hour a day. A lower strap of the hip brace was designed to prevent coxa valga biomechanically. The effectiveness of the hip brace on coxa valga was assessed by measurement of the NSA and head-shaft angle at enrollment and 6 and 12 months after enrollment. Results: Sixty-six participants were enrolled, and 33 patients were assigned to each group. Changes in the mean NSA of both sides and the NSA of left side showed significant differences between the 2 groups over 12 months (mean NSA of both sides, −1.12 ± 3.64 in the study group and 1.43 ± 3.75 in the control group, P = .023; NSA of the left side, −1.72 ± 5.38 in the study group and 2.01 ± 5.22 in the control group, P = .008). Conclusions: The hip brace was effective in preventing the progression of coxa valga and hip displacement, suggesting that the prevention of coxa valga using hip brace is a contributing factor in prevention of hip displacement.