Cauda equina repair in the rat: Part 1. Stimulus-evoked EMG for identifying spinal nerves innervating intrinsic tail muscles
Document Type
Article
Publication Title
Journal of Neurotrauma
Abstract
Cauda equina injuries may produce severe leg and pelvic floor dysfunction, for which no effective treatments exist. We are developing a rat cauda equina injury model to allow nerve root identification and surgical repair. One possible difficulty in implementing any repair strategy after trauma in humans involves the correct identification of proximal and distal ends of nerve roots separated by the injury. Two series of studies were carried out. In Series 1, we electrically stimulated segmental contributors to the dorsal and ventral caudales nerves in order to characterize the recruitment patterns of muscles controlling rat tail movements. In Series 2, we attempted to identify individual nerve roots forming the cauda equina by both level of origin and function (i.e., dorsal or ventral), based solely upon the recruitment patterns in response to electrical stimulation. For Series 1 studies, electrical stimulation of the segmental contributors showed that all nerve roots-from the sixth lumbar to the first coccygeal-contributed to recruitment of muscles found at the base of the tail. Intrinsic tail muscles lying more distally in the tail showed a more root-specific pattern of innervation. For Series 2, the rate of successful identification of an unknown nerve root as being ventral was very high (>95%), and only somewhat lower (∼80%) for dorsal roots. Correctly identifying the level of origin of that root was more difficult, but for ventral roots this rate still exceeded 90%. Using the rat cauda equina model, we have shown that stimulus-evoked EMG can be used to identify ventral nerve roots innervating tail muscles with a high degree of accuracy. These findings support the feasibility of using this conceptual approach for identifying and repairing damaged human cauda equina nerve roots based on stimulus-evoked recruitment of muscles in the leg and pelvic floor. © Copyright 2009, Mary Ann Liebert, Inc.
First Page
1405
Last Page
1416
DOI
10.1089/neu.2008.0791
Publication Date
8-1-2009
Recommended Citation
Blaskiewicz, Don J.; Smirnov, Igor; Cisu, Tudor; DeRuisseau, Lara R.; Stelzner, Dennis J.; and Calancie, Blair, "Cauda equina repair in the rat: Part 1. Stimulus-evoked EMG for identifying spinal nerves innervating intrinsic tail muscles" (2009). Basic Sciences Faculty Publications. 86.
https://doi.org/10.1089/neu.2008.0791
https://collections.uhsp.edu/basic-sciences_pubs/86