Immediate In-Brace Correction Influences Scoliosis Outcomes
New study offers insight into brace biomechanics in adolescent idiopathic scoliosis
FRIDAY, Aug. 20 (HealthDay News) -- Prior analyses of the effect of bracing on long-term outcomes for correction of adolescent idiopathic scoliosis identified immediate in-brace correction as influential; a new study confirming these analyses and giving insight into the biomechanics of bracing has been published in the Aug. 15 issue of Spine.
Julien Clin, Ph.D., of the Sainte-Justine University Hospital Center in Montreal, and colleagues evaluated 1,024 virtual braces to compare their biomechanical effects. They used multiview radiographs and surface topography techniques to acquire three-dimensional geometry of three patients, and created a finite element model of the patients' trunks, including gravitational forces and a parametric brace model. They tested the different braces for each patient.
The researchers found that the degree of immediate correction necessary for nullifying the bending moment averaged 48 percent for a flexible spine model and 27 percent for a stiff spine model. They determined that the braces corrected the apical vertebrae bending moment more in the flexible spine model than the stiff spine model. In addition, they found that spine stiffness and spine segment influence the amount of correction needed to nullify the bending moment and offset the progression of scoliosis. They concluded that immediate in-brace correction is important for predicting long-term treatment outcome and for providing insights into brace biomechanics.
"This study showed there was a correlation between immediate in-brace correction and the compressive asymmetrical loading of the spine in the frontal plane due to gravity. According to the Hueter-Volkmannn principle, this relationship should then lead to a correlation between immediate in-brace correction and long-term outcome of the treatment," the authors write.