Editorial Type:
Biomechanics

Effects of conventional and slanted ventral slot procedures on the biomechanical behavior of the C5-C6 vertebral motion unit in dogs

Haisheng Yang Department of Basic Medical Sciences, Purdue University, West Lafayette, IN 47907.

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 PhD
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Nicolaas E. Lambrechts Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Purdue University, West Lafayette, IN 47907.

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 BVSC, MMED VET
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Michael Lehner Weldon School of Biomedical Engineering, College of Engineering, Purdue University, West Lafayette, IN 47907.

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Gremah M. Adam Department of Biological Sciences, College of Science, Purdue University, West Lafayette, IN 47907.

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Rebecca A. Packer Department of Basic Medical Sciences, Purdue University, West Lafayette, IN 47907.
Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Purdue University, West Lafayette, IN 47907.

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Trevor W. Moore Department of Basic Medical Sciences, Purdue University, West Lafayette, IN 47907.
Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Purdue University, West Lafayette, IN 47907.

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Russell P. Main Weldon School of Biomedical Engineering, College of Engineering, Purdue University, West Lafayette, IN 47907.

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DOI:
https://doi.org/10.2460/ajvr.77.8.846
Volume/Issue:
Volume 77: Issue 8
Online Publication Date:
01 Aug 2016
Restricted access
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Abstract

OBJECTIVE To compare the effects of conventional and slanted ventral slot procedures on the biomechanical behavior of the C5-C6 vertebral motion unit (VMU) in dogs.

SAMPLE 14 vertebral columns (C4 through C7) from canine cadavers.

PROCEDURES Specimens were assigned to a conventional or slanted ventral slot group (n = 7/group). For each specimen, the C5-C6 VMU was tested in ventral and dorsal bending and positive and negative axial torsion before and after surgery. Range of motion (ROM), stiffness, and energy absorption were compared between the 2 groups.

RESULTS Both procedures significantly increased the ROM and stiffness and significantly decreased the energy absorption of the C5-C6 VMU in ventral and dorsal bending. Both procedures also increased the ROM in positive and negative axial torsion. In negative torsion, total stiffness and stiffness over the maximum ROM tested decreased less for the slanted slot procedure than for the conventional slot procedure. There were no significant differences between procedures for any of the other biomechanical outcomes examined.

CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that the biomechanical response of the C5-C6 VMU to the conventional and slanted ventral slot procedures was not significantly different, especially when considering postsurgical instability induced by both procedures. This was most likely due to disruption of the nucleus pulposus and dorsal annulus fibrosus of the disk with both procedures. On the basis of these findings, neither procedure appeared biomechanically superior. Comparative clinical studies are warranted to further evaluate the 2 procedures.

Abstract

OBJECTIVE To compare the effects of conventional and slanted ventral slot procedures on the biomechanical behavior of the C5-C6 vertebral motion unit (VMU) in dogs.

SAMPLE 14 vertebral columns (C4 through C7) from canine cadavers.

PROCEDURES Specimens were assigned to a conventional or slanted ventral slot group (n = 7/group). For each specimen, the C5-C6 VMU was tested in ventral and dorsal bending and positive and negative axial torsion before and after surgery. Range of motion (ROM), stiffness, and energy absorption were compared between the 2 groups.

RESULTS Both procedures significantly increased the ROM and stiffness and significantly decreased the energy absorption of the C5-C6 VMU in ventral and dorsal bending. Both procedures also increased the ROM in positive and negative axial torsion. In negative torsion, total stiffness and stiffness over the maximum ROM tested decreased less for the slanted slot procedure than for the conventional slot procedure. There were no significant differences between procedures for any of the other biomechanical outcomes examined.

CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that the biomechanical response of the C5-C6 VMU to the conventional and slanted ventral slot procedures was not significantly different, especially when considering postsurgical instability induced by both procedures. This was most likely due to disruption of the nucleus pulposus and dorsal annulus fibrosus of the disk with both procedures. On the basis of these findings, neither procedure appeared biomechanically superior. Comparative clinical studies are warranted to further evaluate the 2 procedures.

Contributor Notes

Dr. Yang's present address is Department of Pediatric Surgery, Shriners Hospital for Children, McGill University, Montreal, QC H3G IA4, Canada.

Drs. Lambrecht and Packer's present address is Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523.

Address correspondence to Dr. Main (rmain@purdue.edu).
Cover American Journal of Veterinary Research
American Journal of Veterinary Research
Publication Date:
01 Aug 2016

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