The human scoliotic spine is mathematically modelled by employing the classical non-linear theory of curved beam-columns. A realistically representative muscle force system is included in the model. Scoliosis due to asymmetrical bi-lateral muscular contractions has been studied and arbitrary large displacements and curvatures are allowed. The two-dimensional model allowing curvature in the frontal plane can show the progression of a scoliotic curve from an initially straight configuration. For various parameter values, particularly muscle asymmetry, the model attempts to simulate the progression of actual scoliotic curves. Once these curves have been simulated, forces corresponding to corrective surgical systems are applied to the scoliotic spine. The corresponding corrected curves are then compared with those produced by a finite element model and also to the actual clinical curve. The comparisons were very favourable, considering the simplicity of the continuous model. The commonly observed phenomenon of the scoliotic curve lying to the weaker side of the back in terms of muscle strength is reproduced and explained by the model. The possible usefulness of continuous spinal models to analyse the overall deformation of the spine under various loading conditions can then be deduced.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/0141-5425(91)90093-m | DOI Listing |
J Clin Med
January 2025
Department of Spine Surgery, IRCCS Istituto Ortopedico Rizzoli, 40136 Bologna, Italy.
: Surgery for adolescent idiopathic deformities is often aimed at improving aesthetic appearance, striving for the best possible correction. However, severe and rigid scoliotic curves not only present aesthetic issues but can also compromise cardiopulmonary health and cause early neurological impairment due to spinal cord compression, posing significant risks of morbidity and mortality if untreated. Conservative treatments are ineffective for severe curves, defined by scoliotic angles over 70° and flexibility below 30% on lateral bending X-rays.
View Article and Find Full Text PDFSci Rep
January 2025
Tuina department, Hangzhou Hospital of Traditional Chinese Medicine Hangzhou TCM Affiliated to Zhejiang Chinese Medicine University, Hangzhou, China.
To determine whether relative anterior spinal overgrowth (RASO) occurs regardless of scoliosis segments and severity, and to explore the pattern of vertebral body height changes in adolescent idiopathic scoliosis (AIS). A total of 125 AIS and 179 non-scoliotic adolescents were enrolled. The anterior vertebral body height (VBHa) and posterior vertebral body height (VBHp) were measured on lateral spine radiographs, and the VBHa/VBHp ratio was calculated.
View Article and Find Full Text PDFSpine Deform
January 2025
Department of Spine Surgery, University Hospital of Vall d'Hebron, 129 Passeig Vall d´Hebron, 08035, Barcelona, Spain.
Purpose: To determine patient-reported clinical status in a cohort of patients operated on during adolescence for adolescent idiopathic scoliosis (AIS) using Cotrel-Dubousset instrumentation after a minimum follow-up (FU) of 25 years.
Methods: Multicentric cross-sectional observational study. We assessed the clinical status of patients using the lumbar-pain numeric rating scale (NRS), ODI, SRS-22r, SF-36, and EQ-5D-5L.
J Orthop Surg Res
January 2025
Biomedical Engineering Department, Universidad de los Andes, Bogotá, Colombia.
Spine Deform
January 2025
Gastroenterology and Hepatology Research Center, Institute of Basic and Clinical Physiology Sciences, Kerman University of Medical Sciences, Kerman, Iran.
Background: To investigate the association between lumbar degenerative scoliosis and the dural sac cross-sectional area (DSCA), the lumbar canal anterior-posterior (LCAP) diameter, and the neural foraminal cross-sectional area (NFCA) in relation to facet joint tropism (FJT).
Methods: In a retrospective case-control study, we analyzed data from 160 patients referred for lumbar magnetic resonance imaging (MRI) between January 2020 and December 2022. Cobb's angle on anteroposterior lumbosacral X-ray is served to identify the presence of degenerative lumbar scoliosis-Cobb's angle exceeding 10 degrees-, and axial T2W MRI is implemented to evaluate facet joint angles and tropism-defined as a difference exceeding 10 degrees between the facet joint angles at each level-, DSCA, LCAP, and NFCA.
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!