The biomechanical influence of thoraco-lumbo-sacral bracing, a commonly employed treatment in scoliosis, is still not fully understood. The aim of this study was to compare the immediate corrections generated by different virtual braces using a patient-specific finite element model (FEM) and to analyze the most influential design factors. The 3D geometry of three patients presenting different types of curves was acquired with a multi-view X-ray technique and surface topography. A personalized FEM of the patients’ trunk and a parametric model of a virtual custom-fit brace were then created. The installation of the braces on the patients was simulated. The influence of 15 design factors on the 3D correction generated by the brace was evaluated following a design of experiments simulation protocol allowing computing the main and two-way interaction effects of the design factors. A total of 12,288 different braces were tested. Results showed a great variability of the braces effectiveness. Of the 15 design factors investigated, according to the 2 modalities chosen for each one, the 5 most influential design factors were the position of the brace opening (posterior vs. anterior), the strap tension, the trochanter extension side, the lordosis design and the rigid shell shape. The position of the brace opening modified the correction mechanism. The trochanter extension position influenced the efficiency of the thoracic and lumbar pads by modifying their lever arm. Increasing the strap tension improved corrections of coronal curves. The lordosis design had an influence in the sagittal plane but not in the coronal plane. This study could help to better understand the brace biomechanics and to rationalize and optimize their design.
This is a preview of subscription content, access via your institution.
Buy single article
Instant access to the full article PDF.
Tax calculation will be finalised during checkout.
Subscribe to journal
Immediate online access to all issues from 2019. Subscription will auto renew annually.
Tax calculation will be finalised during checkout.
Andriacchi TP, Schultz AB, Belytschko TB, Dewald R (1976) Milwaukee brace correction of idiopathic scoliosis. A biomechanical analysis and a retrospective study. J Bone Jt Surg Am 58:806–815
Aubin CE, Dansereau J, de Guise JA, Labelle H (1997) Rib cage-spine coupling patterns involved in brace treatment of adolescent idiopathic scoliosis. Spine 22:629–635
Aubin CE, Dansereau J, de Guise JA, Labelle H (1996) A study of biomechanical coupling between spine and rib cage in the treatment by orthosis of scoliosis. Ann Chir 50:641–650
Aubin CE, Descrimes JL, Dansereau J, Skalli W, Lavaste F, Labelle H (1995) Geometrical modeling of the spine and the thorax for the biomechanical analysis of scoliotic deformities using the finite element method. Ann Chir 49:749–761
Box GEP, Hunter JS (2000) The 2 k-p fractional factorial designs. Part I. Technometrics 42:28–47
Castro FP Jr (2003) Adolescent idiopathic scoliosis, bracing, and the Hueter-Volkmann principle. Spine J 3:180–185
Cheriet F, Remaki L, Bellefleur C, Koller A, Labelle H, Dansereau J (2002) A new X-ray calibration/reconstruction system for 3D clinical assessment of spinal deformities. Stud Health Technol Inform 91:257–261
Clin J, Aubin CE, Labelle H (2007) Virtual prototyping of a brace design for the correction of scoliotic deformities. Med Biol Eng Comput 45:467–473
Delorme S, Petit Y, de Guise JA, Labelle H, Aubin CE, Dansereau J (2003) Assessment of the 3-d reconstruction and high-resolution geometrical modeling of the human skeletal trunk from 2-D radiographic images. IEEE Trans Biomed Eng 50:989–998
Emans JB (2003) Boston Brace. srs bracing manual (http://wwwsrsorg/professionals/bracing_manuals/)
Emans JB, Kaelin A, Bancel P, Hall JE, Miller ME (1986) The Boston bracing system for idiopathic scoliosis. Follow-up results in 295 patients. Spine 11:792–801
Fortin D, Cheriet F, Beausejour M, Debanne P, Joncas J, Labelle H (2007) A 3D visualization tool for the design and customization of spinal braces. Comput Med Imaging Graph 31:614–624
Gignac D, Aubin CE, Dansereau J, Labelle H (2000) Optimization method for 3D bracing correction of scoliosis using a finite element model. Eur Spine J 9:185–190
Goldberg CJ, Moore DP, Fogarty EE, Dowling FE (2001) Adolescent idiopathic scoliosis: the effect of brace treatment on the incidence of surgery. Spine 26:42–47
Kadoury S, Cheriet F, Dansereau J, Labelle H (2007) Three-dimensional reconstruction of the scoliotic spine and pelvis from uncalibrated biplanar X-ray images. J Spinal Disord Tech 20:160–167
Kadoury S, Cheriet F, Laporte C, Labelle H (2007) A versatile 3D reconstruction system of the spine and pelvis for clinical assessment of spinal deformities. Med Biol Eng Comput 45:591–602
Lenssinck ML, Frijlink AC, Berger MY, Bierman-Zeinstra SM, Verkerk K, Verhagen AP (2005) Effect of bracing and other conservative interventions in the treatment of idiopathic scoliosis in adolescents: a systematic review of clinical trials. Phys Ther 85:1329–1339
Mac-Thiong JM, Petit Y, Aubin CE, Delorme S, Dansereau J, Labelle H (2004) Biomechanical evaluation of the Boston brace system for the treatment of adolescent idiopathic scoliosis: relationship between strap tension and brace interface forces. Spine 29:26–32
Nachemson AL, Peterson LE (1995) Effectiveness of treatment with a brace in girls who have adolescent idiopathic scoliosis. A prospective, controlled study based on data from the Brace Study of the Scoliosis Research Society. J Bone Jt Surg Am 77:815–822
Noonan KJ, Weinstein SL, Jacobson WC, Dolan LA (1996) Use of the Milwaukee brace for progressive idiopathic scoliosis. J Bone Jt Surg Am 78:557–567
Patwardhan AG, Bunch WH, Meade KP, Vanderby R Jr, Knight GW (1986) A biomechanical analog of curve progression and orthotic stabilization in idiopathic scoliosis. J Biomech 19:103–117
Pazos V, Cheriet F, Danserau J, Ronsky J, Zernicke RF, Labelle H (2007) Reliability of trunk shape measurements based on 3-D surface reconstructions. Eur Spine J 16:1882–1891
Pazos V, Cheriet F, Labelle H, Dansereau J (2002) 3D reconstruction and analysis of the whole trunk surface for non-invasive follow-up of scoliotic deformities. Stud Health Technol Inform 91:296–299
Pazos V, Cheriet F, Song L, Labelle H, Dansereau J (2005) Accuracy assessment of human trunk surface 3D reconstructions from an optical digitising system. Med Biol Eng Comput 43:11–15
Perie D, Aubin CE, Lacroix M, Lafon Y, Labelle H (2004) Biomechanical modelling of orthotic treatment of the scoliotic spine including a detailed representation of the brace–torso interface. Med Biol Eng Comput 42:339–344
Perie D, Aubin CE, Petit Y, Labelle H, Dansereau J (2004) Personalized biomechanical simulations of orthotic treatment in idiopathic scoliosis. Clin Biomech (Bristol, Avon) 19:190–195
Petit Y, Aubin CE, Labelle H (2004) Patient-specific mechanical properties of a flexible multi-body model of the scoliotic spine. Med Biol Eng Comput 42:55–60
Rigo M, Negrini S, Weiss HR, Grivas TB, Maruyama T, Kotwicki T (2006) SOSORT consensus paper on brace action: TLSO biomechanics of correction (investigating the rationale for force vector selection). Scoliosis 1:11
Rowe DE, Bernstein SM, Riddick MF, Adler F, Emans JB, Gardner-Bonneau D (1997) A meta-analysis of the efficacy of non-operative treatments for idiopathic scoliosis. J Bone Jt Surg Am 79:664–674
Sanders JE, Greve JM, Mitchell SB, Zachariah SG (1998) Material properties of commonly used interface materials and their static coefficients of friction with skin and socks. J Rehabil Res Dev 35:161–176
Upadhyay SS, Nelson IW, Ho EK, Hsu LC, Leong JC (1995) New prognostic factors to predict the final outcome of brace treatment in adolescent idiopathic scoliosis. Spine 20:537–545
van Rhijn LW, Veraart BE, Plasmans CM (2003) Application of a lumbar brace for thoracic and double thoracic lumbar scoliosis: a comparative study. J Pediatr Orthop B 12:178–182
Wynarsky GT, Schultz AB (1991) Optimization of skeletal configuration: studies of scoliosis correction biomechanics. J Biomech 24:721–732
This study was funded by the Natural Sciences and Engineering Research Council of Canada.
About this article
Cite this article
Clin, J., Aubin, CE., Parent, S. et al. Comparison of the biomechanical 3D efficiency of different brace designs for the treatment of scoliosis using a finite element model. Eur Spine J 19, 1169–1178 (2010). https://doi.org/10.1007/s00586-009-1268-2
- Finite element model