Logo image
Scoliosis Induction in the Porcine Spine Using a Growth-Modulating Posterior Tether: Finite Element Model Development and Calibration
Journal article   Open access   Peer reviewed

Scoliosis Induction in the Porcine Spine Using a Growth-Modulating Posterior Tether: Finite Element Model Development and Calibration

Christian Reynold D'Andrea, Mattan R Orbach, Alessandra Fusco, Edward Vresilovic, Brian D. Snyder, Thomas P Schaer, Patrick J. Cahill and Sriram Balasubramanian
Annals of Biomedical Engineering, Forthcoming
06 Oct 2026
PMID: 42836904
Featured in Collection :   Drexel's Newest Publications
url
https://doi.org/10.1007/s10439-026-04403-3View
Published, Version of Record (VoR) Open Access via Drexel Libraries Read and Publish Program 2026 Open CC BY V4.0

Abstract

Scoliosis Finite element Porcine Implant Growth modulation Spine biomechanics Tether Biomechanics
Purpose Predictable correction of early onset scoliosis through mechanical modulation of endochondral growth requires understanding vertebral stress–growth relationships. Here, we develop image-based finite element models (FEMs) to estimate vertebral stress–growth relationships under prescribed loading conditions using a porcine model of spine deformity induced mechanically via a posterolateral tether, assuming that, after initial tether-induced elastic deformation, subsequent deformity develops solely from vertebral endochondral growth against the tether and elastic anatomical structures. Methods Image-based FEMs were generated to simulate juvenile Yorkshire pigs instrumented with a posterolateral tether implant which applied asymmetric force across the spine. FEM growth parameters were calibrated to best match in vivo data using landmark points obtained from 3D imaging for each pig. Results Asymmetric stresses generated by loading of the posterolateral offset cable produced multi-planar spine deformity. Calibrated FEMs achieved moderate agreement with frontal plane projections of the deformity: Cobb angle (MAE = 4.6–8.5° across all pigs and timepoints) and anatomic landmark point correspondence (MAE = 2.1–2.9 mm), but sagittal plane agreement was more limited, partly attributable to variability in positioning during imaging. FEM-derived vertebral body growth rates were reduced for vertebrae along the concavity of the deformity. Conclusion Image-based FEMs estimated vertebral stress–growth relationships and reproduced deformity with comparable Cobb angle error to an existing parametric FE model (current 2.5 ± 1.6° vs. reported ~ 2.0 ± 2.4° in a single-pig matched comparison) with realistic baseline IVD stresses (current ~ 0.45 MPa vs. reported 0.48 MPa in the growth plate). With expanded validation, such models may support preclinical evaluation of implant designs and surgical configurations prior to in vivo testing.

Metrics

1 Record Views

Details

Logo image