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

Background: 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. Aim: 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. Design: This is an observational controlled cohort study nested in a prospective clinical on-going database in patients with Scheuermann kyphosis. Setting: Inpatients and outpatients in Rome. Methods: 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. Results: 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). Conclusions: The results confirm that conservative treatment in Scheuermann's kyphosis during skeletal growth is effective. Bracing treatment can remodel the deformed vertebrae. Clinical rehabilitation impact: At the 10-year follow-up after bracing, kyphosis curve correction was stable over time.