Spinal cord deformation during injury of the cervical spine in head-first impact

Saari, A.<sup>1,3</sup>; Itshayek, E.<sup>2,3</sup>; Nelson, T. S.<sup>1,3</sup>; Morley, P. L.<sup>1,3</sup>; Cripton, P. A.<sup>1,3</sup>

Affiliations

¹Injury Biomechanics Laboratory and Division of Orthopaedic Engineering Research, Departments of Mechanical Engineering and Orthopaedics, University of British Columbia Vancouver, Canada

²Department of Orthopaedics, University of British Columbia Vancouver, Canada

²International Collaboration on Repair Discoveries (ICORD) University of British Columbia Vancouver, Canada

Abstract and keywords

There is a need to better understand the biomechanics of spinal cord injuries especially at the level of the spinal cord itself. We report results from a series of head-first impacts using human cadaveric cervical spines (N = 6) and a custom drop tower. To improve the biofidelity of the column response during impact muscle forces were simulated using a constant follower load of 150N. A radio-opaque, biofidelic surrogate cord was imaged using cineradiography at 1000fps to quantify the transverse spinal cord deformation during injury. A variety of injury modes commonly associated with axial head first impact were induced. The average maximum cord compression was 49%, occurring at 12.3ms after impact. The follower load appeared to eliminate "snap-through" buckling in these tests.

Keywords: Neck; Spinal Cord Injury; Drop Tests

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Cited By (5)

Year	Entry
2008	Van Toen C, Nelson TS, Jones CF, Street J, Cripton PA. Development of an in vitro model of head-first impact with a Hybrid III head, surrogate spinal cord, and simulated neck muscles. In: Proceedings of the 36th International Workshop on Human Subjects for Biomechanical Research. November 2, 2008; San Antonio, TX.
2011	Newell RS, Siegmund GP, Cripton PA. Neck vertebral alignment and muscle activation is affected by whole body inversion. In: Proceedings of the 39th International Workshop on Human Subjects for Biomechanical Research. 2011.
2009	Van Toen C, Jones CF, Nelson TS, Street J, Cripton PA. Simulation of head-first impact using cervical spine specimens, simulated neck muscles, and a Hybrid III ATD head. In: Proceedings of the 5th Ohio State University Injury Biomechanics Symposium. May 17-19, 2009; Columbus, OH.
2010	Lucas E, Liu J, Russell C, Tetzlaff W, Cripton P. High speed radiography can be used to measure dynamic spinal cord deformation in an in vivo rodent model. In: Proceedings of the 6th Ohio State University Injury Biomechanics Symposium. May 16-18, 2010; Columbus, OH.
2011	Nelson TS. Towards a Neck Injury Prevention Helmet for Head-First Impacts: A Mechanical Investigation [PhD thesis]. Vancouver, BC: University of British Columbia; December 2011.