Alternately repetitive cast/brace (ARCB) treatment for larger-magnitude early-onset scoliosis: A retrospective cohort study

Abstract

Objective: The present study aims to investigate the potential of ARCB-T as a delayed tactic even for larger-magnitude scoliosis. Methods: In the present retrospective cohort study, the inclusion criteria were as follows: (1) EOS and 2) age of initiation for ARCB-T ≤ 4 years. Consecutively enrolled 120 patients since 1995–2016 met these criteria. They were divided into the following two groups in terms of initial scoliosis of 50°: Cast Larger-Group (CL-G; main scoliosis ≥50°; n = 78) and Cast Mild-Group (CM-G; main scoliosis <50°; n = 42). Etiologies were as follows: congenital/structural defects (CS/ST; n = 55); infantile idiopathic scoliosis (IIS; n = 28); syndromic scoliosis (SS; n = 32); and neuromuscular scoliosis ( n = 5). ARCB-T was switched to surgical intervention in 52 and 17 patients in the CL-G and CM-G, respectively. The endpoints were the progression rate during ARCB-T and the magnitude of scoliosis at the end of ARCB-T. We compared scoliosis measured at initiation and end of ARCB-T, and scoliosis in the initial cast placement between the two groups. Results: We observed a reduction of scoliosis <30° in 11.5% and 28.6% patients in the CL-G and CM-G, respectively. While, patients with scoliosis >70° did not display improvement of scoliosis <30°. Early initiation of ARCB-T significantly correlated with a lower progression rate ( P = 0.0384). Patients with larger-magnitude scoliosis at the first casting exhibited significantly larger-magnitude scoliosis at the end of ARCB-T ( P < 0.0001). Better correction of scoliosis by initial casting decreased the progression rate ( P = 0.0113) among patients in both the groups. Although the correction of scoliosis by initial casting did not correlate with the progression rate in the CL-G ( P = 0.1153), the progression rate during ARCB-T significantly correlated with the correction by casting in patients with ≥70° or 80° of scoliosis ( P = 0.0016). The diagnoses correlated with the efficacy of ARCB-T and IIS exhibited a significantly better progression rate (−3.0°/year) than other etiologies. Conclusion: Despite being limited in the suppression of the progression of larger-magnitude scoliosis, ARCB-T works less efficiently as a delayed tactic to surgery and could be an option for larger-magnitude scoliosis if it displays better correction at the first cast placement. as a delayed for