Three dimensional analysis of brace biomechanical efficacy for patients with AIS

Abstract

Purpose Corrective three dimensional (3D) effect of different braces is debatable. We evaluated differences in in-brace radiographic correction comparing a custom thoracic-lumbo-sacral-orthosis (TLSO) (T) brace to a Chêneau type TLSO (C) brace using 3D EOS reconstruction technology. Our primary research question was the 3D effect of brace on the spine and in particularly the apical vertebra rotation (AVR). Methods This was a retrospective comparative analysis of patients with adolescent idiopathic scoliosis who had orthogonal AP and lateral X-rays with and without brace. A 3D image of the spine was reconstructed. Coronal, sagittal and axial spine parameters were measured before bracing and then on the first post-brace X-ray. Brace efficacy in controlling coronal, sagittal and axial parameters was evaluated.Results Eighteen patients treated with the C brace and ten patients treated with the T brace were included. No difference was found regarding patients' age, gender, magnitude of Cobb angle, sagittal parameters or AVR at inclusion. Following bracing, AVR was significantly reduced by the C brace compared to the T brace [average correction of 8.2°vs. 4.9°(P = 0.02)]. Coronal and sagittal correction did not differ significantly between the two groups.Conclusions By utilizing a novel 3D reconstruction technology, we were able to demonstrate that braces differ in their immediate effects on the spine. Although clinical relevance should be evaluated in a future trial we feel that the ability to measure treatment effects in 3D, and especially the transverse plane, is an important tool when evaluating different treatments.

Experimental validation of a patient-specific model of orthotic action in adolescent idiopathic scoliosis

“…This is slightly better than the 50% cohort improvement previously reported by Courvoisier et al [5]. The absolute Cobb angle correction observed in this study was similar to the one previously reported by Lebel et al [19] (-10.4° against ~14°), but VAR correction was lower (-1.7° against -6.5°). Comparison with previous studies, in particular concerning absolute values of correction, is difficult because of differences in the initial cohort (age, curve topology), brace compliance [3], etc.…”

Long-term effects of the Chêneau brace on coronal and sagittal alignment in adolescent idiopathic scoliosis

“…11 The purpose of this study was to analyze the variability of the long-term effects of bracing on AIS. The main finding of the study is that the Chêneau brace induces a significant decrease in kyphosis, lordosis, and PT.…”

“…A previous study found no statistically significant immediate modification of transverse plane parameters. 4 Lebel et al 11 compared the differences in immediate 3D effects between the Chêneau brace and the Boston brace by assessing 3D reconstructions. They demonstrated that the Chêneau brace had a significant de-rotation effect compared with the Boston brace.…”

Current concepts in the diagnosis and management of adolescent idiopathic scoliosis

“…Label et al evaluated the in in-brace radiographic correction for patients treated with either the thoraco-lumbo-sacral orthosis (TLSO) or the RCOs. Following bracing, they found that the apical vertebral rotation was significantly reduced by the RCOs when compared with the TLSO by on average 8.2°v s. 4.9° [54]. Another study evaluated the therapeutic success of the RCOs.…”