Long-term outcome after brace treatment of Scheuermann's kyphosis: an observational controlled cohort study.

Abstract

In the literature, there are several papers on Scheuermann's kyphosis. It is a structural deformity of the spine that is characterized by anterior wedging of 5° or more of 3 adjacent thoracic vertebral bodies with kyphosis measuring greater than 45° between T5 and T12. Bracing treatment is able to obtain, during skeletal growth, remodeling of the deformed vertebrae. The aim of this study was to evaluate the effectiveness of conservative treatment in Scheuermann's kyphosis at a minimum follow-up of 10 years. This is an observational controlled cohort study nested in a prospective clinical on-going database in patients with Scheuermann kyphosis. Inpatients and outpatients in Rome. From a consecutive series of patients included in a prospective database, we selected 158 patients with thoracic Scheuermann's kyphosis who were treated using an anti-gravity brace: 93 males and 65 females. The mean age at the beginning of the treatment was 14 years. The time bracing prescribed was a max of 20 hours daily and a min of 16 hours daily. Weaning was started when a full recovery of vertebral geometry was seen on a lateral radiograph view or when growing was ended. Radiographical measurements were performed on radiographs from a lateral projection at baseline (t1), at the end of the treatment (t2) and at 10 years of minimum follow-up (t3). To avoid the great variance in the range of curve angles in thoracic kyphosis (TK) that rely on the radiological position, X-rays were performed observing the following position: standing with head straight, arms bent at 45° and hands lightly placed on a support. The anterior wedging angle (Alpha) of the apex vertebra and the degrees of the curve (Cobb methods) were analyzed using statistical analysis. The results from our study showed that in 158 patients with TK curves, the mean Cobb angle was 57.6±6.3 SD at baseline, 43.3±7.8 SD at the end of treatment and 44.49±7.4 SD at ten years of follow-up. The alpha angle was 14.43±2.535 SD at baseline and 8.571±3.589 SD at the end of treatment, and after ten years of follow-up, it was 8.654±3.57 SD. The mean duration of treatment was 28.42±12.07 months, and the mean follow-up was 128.3±11.07 months. The difference between baseline and end of treatment, tested with the one-way ANOVA comparisons test, was significant (P<0.0001) for both Cobb angle and alpha; instead, the difference between the end of treatment and follow-up was not significant (P=0.3277). The results confirm that conservative treatment in Scheuermann's kyphosis during skeletal growth is effective. Bracing treatment can remodel the deformed vertebrae. At the 10-year follow-up after bracing, kyphosis curve correction was stable over time.