Citation

Saari A, Itshayek E, Cripton PA. J. Biomech. 2011; 44(14): 2565-2571.

Affiliation

Orthopaedic and Injury Biomechanics Group, University of British Columbia, Vancouver, Canada; Department of Mechanical Engineering, University of British Columbia, 2054-6250 Applied Science Lane, Vancouver, BC, Canada V6T 1Z4; International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, Canada.

Copyright

(Copyright © 2011, Elsevier Publishing)

DOI

10.1016/j.jbiomech.2011.06.015

PMID

21840526

Abstract

The relationship between bony spinal column and spinal cord injury during an injury event is not well understood. While several studies have measured spinal canal occlusion during axial impact, there has been limited work done to quantify the spinal cord compression or deformation during simulated injury. Because the cord is a viscoelastic solid it may provide resistance to bone fragments, ligaments or other elements that move into the canal and impinge it during column injury. This would differentiate the measurement of cord compression from the measurement of occlusion of an empty canal. In the present study, a novel method of visualizing and quantifying spinal cord deformation during dynamic head-first impact of ex vivo human cervical spine specimens (N=6) was developed. A radiodense, biofidelic surrogate spinal cord was imaged in the spinal canal using high speed cineradiography at 1000 frames per second. The dorsal-ventral diameter of the cord was measured at 1.5mm increments along its length for each frame of the radiographic footage. The resulting cord deformations were used to determine the theoretical neurological outcome of the impact based on published in vivo ferret studies. The corresponding probability of recovery for the spinal cord deformations in these tests ranged between 8% for atlantoaxial dislocation injury and 95% for mid-cervical spine hyperextension injury (based on the ferret data). Clinically relevant spinal column fracture patterns were produced in this study.

Language: en