Faculty Collaboration Database

Cervical vertebral strain measurements under axial and eccentric loading. J Biomech Eng 1995 Nov;117(4):474-8

Date

11/01/1995

Pubmed ID

8748531

DOI

10.1115/1.2794210

Scopus ID

2-s2.0-0029394881 (requires institutional sign-in at Scopus site)   71 Citations

Abstract

The mid to lower cervical spine is a common site for compression related injury. In the present study, we determined the patterns of localized strain distribution in the anterior aspect of the vertebral body and in the lateral masses of lower cervical three-segment units. Miniature strain gages were mounted to human cadaveric vertebrae. Each preparation was line-loaded using a knife-edge oriented in the coronal plane that was moved incrementally from anterior to posterior to induce compression-flexion or compression-extension loading. Uniform compressive loading and failure runs were also conducted. Failure tests indicated strain shifting to "restabilize" the preparation after failure of a component. Under these various compressive loading vectors, the location which resulted in the least amount of deformation for a given force application (i.e., stiffest axis) was quantified to be in the region between 0.5- 1.0 cm anterior to the posterior longitudinal ligament. The location in which line-loading produced no rotation (i.e., balance point) was in this region; it was also close to where the vertebral body strains change from compressive to tensile. Strain values from line loading in this region produced similar strains as recorded under uniform compressive loading, and this was also the region of minimum strain. The region of minimum strain was also more pronounced under higher magnitudes of loading, suggesting that as the maximum load carrying capacity is reached the stiffest axis becomes more well defined.

Author List

Pintar FA, Yoganandan N, Pesigan M, Reinartz J, Sances A Jr, Cusick JF

Authors

Joseph F. Cusick MD Adjunct Professor in the Neurosurgery department at Medical College of Wisconsin
Frank A. Pintar PhD Chair, Professor in the Biomedical Engineering department at Medical College of Wisconsin
Narayan Yoganandan PhD Professor in the Neurosurgery department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Aged
Biomechanical Phenomena
Cervical Vertebrae
Female
Humans
Male
Middle Aged
Range of Motion, Articular
Reference Values
Tensile Strength
Weight-Bearing