Comparison of neuropathic pain induced by the application of normal and mechanically compressed nucleus pulposus to lumbar nerve roots in the rat
Article first published online: 1 JAN 2006
Copyright © 2003 Orthopaedic Research Society
Journal of Orthopaedic Research
Volume 21, Issue 3, pages 535–539, May 2003
How to Cite
Kawakami, M., Hashizume, H., Nishi, H., Matsumoto, T., Tamaki, T. and Kuribayashi, K. (2003), Comparison of neuropathic pain induced by the application of normal and mechanically compressed nucleus pulposus to lumbar nerve roots in the rat. J. Orthop. Res., 21: 535–539. doi: 10.1016/S0736-0266(02)00192-4
- Issue published online: 1 JAN 2006
- Article first published online: 1 JAN 2006
- Manuscript Accepted: 19 SEP 2002
- Manuscript Received: 3 APR 2002
- Japan Ministry of Education, Science, Sports and Culture
- Grand-in-Aid for Scientific Research. Grant Number: 13671536, 2001
We studied whether applying nucleus pulposus tissue, obtained from tail intervertebral discs that had been subjected to chronic mechanical compression, to the lumbar nerve roots produces hyperalgesia, which is thought to be a pain-related behavior in the rat. An Ilizarov-type apparatus was used for immobilization and chronically applied compression of the rat tail for eight weeks. Three weeks after application of extracted nucleus pulposus tissue on the lumbar nerve roots, motor function, sensitivity to noxious mechanical stimuli was measured. Eight weeks after application of the apparatus, the instrumented vertebrae were resected and sections were stained with hematoxylin and eosin to evaluate degeneration of the intervertebral disc. Mechanical hyperalgesia observed in rats treated with the compressed nucleus pulposus tissue was greater and of longer duration than in the rats treated with normal and non-compressed discs. The nucleus pulposus in the instrumented vertebrae showed some histological degeneration. In conclusion, chronic mechanical compression of nucleus pulposus, which resulted in degeneration to some extent, enhanced mechanical hyperalgesia, which was induced by application of nucleus pulposus on the nerve root in the rat. Degenerative intervertebral discs might induce more significant pain than normal intervertebral discs.
© 2002 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.