Biomechanical Effects of Thoracolumbosacral Orthosis Design Features on 3D Correction in Adolescent Idiopathic Scoliosis: A Comprehensive Multicenter Study. Spine (Phila Pa 1976) 2022 Aug 01;47(15):1103-1110
Date
03/12/2022Pubmed ID
35275852DOI
10.1097/BRS.0000000000004353Scopus ID
2-s2.0-85130019388 (requires institutional sign-in at Scopus site) 7 CitationsAbstract
STUDY DESIGN: Multicenter numerical study.
OBJECTIVE: To biomechanically analyze and compare various passive correction features of braces, designed by several centers with diverse practices, for three-dimensional (3D) correction of adolescent idiopathic scoliosis.
SUMMARY OF BACKGROUND DATA: A wide variety of brace designs exist, but their biomechanical effectiveness is not clearly understood. Many studies have reported brace treatment correction potential with various degrees of control, making the objective comparison of correction mechanisms difficult. A Finite Element Model simulating the immediate in-brace corrective effects has been developed and allows to comprehensively assess the biomechanics of different brace designs.
METHODS: Expert clinical teams (one orthotist and one orthopedist) from six centers in five countries participated in the study. For six scoliosis cases with different curve types respecting SRS criteria, the teams designed two braces according to their treatment protocol. Finite Element Model simulations were performed to compute immediate in-brace 3D correction and skin-to-brace pressures. All braces were randomized and labeled according to 21 design features derived from Society on Scoliosis Orthopaedic and Rehabilitation Treatment proposed descriptors, including positioning of pressure points, orientation of push vectors, and sagittal design. Simulated in brace 3D corrections were compared for each design feature class using ANOVAs and linear regressions (significance P ≤ 0.05).
RESULTS: Seventy-two braces were tested, with significant variety in the design approaches. Pressure points at the apical vertebra level corrected the main thoracic curve better than more caudal locations. Braces with ventral support flattened the lumbar lordosis. Lateral and ventral skin-to-brace pressures were correlated with changes in thoracolumbar/lumbar Cobb and lumbar lordosis (r =- 0.53, r = - 0.54). Upper straps positioned above T10 corrected the main thoracic Cobb better than those placed lower.
CONCLUSIONS: The corrective features of various scoliosis braces were objectively compared in a systematic approach with minimal biases and variability in test parameters, providing a better biomechanical understanding of individual passive mechanisms' contribution to 3D correction.
Author List
Guy A, Coulombe M, Labelle H, Rigo M, Wong MS, Beygi BH, Wynne J, Hresko MT, Ebermeyer E, Vedreine P, Liu XC, Thometz JG, Bissonnette B, Sapaly C, Barchi S, Aubin CÉAuthors
Xue-Cheng Liu PhD Professor in the Orthopaedic Surgery department at Medical College of WisconsinJohn G. Thometz MD Professor in the Orthopaedic Surgery department at Medical College of Wisconsin
MESH terms used to index this publication - Major topics in bold
AdolescentBraces
Finite Element Analysis
Humans
Kyphosis
Lordosis
Scoliosis
