Cervical Spine Stenosis Measures in Normal Subjects

Authors

Ryan T. Tierney, Temple University
Catherine Maldjian, New York University
Carl G. Mattacola, University of Kentucky
Stephen J. Straub, Quinnipiac University
Michael R. Sitler, Temple University

Abstract

OBJECTIVE: To compare 2 methods of determining cervical spinal stenosis (Torg ratio, space available for the cord [SAC]); determine which of the components of the Torg ratio and the SAC account for more of the variability in the measures; and present standardized SAC values for normal subjects using magnetic resonance imaging (MRI).

DESIGN AND SETTING: The research design consisted of a posttest-only, comparison-group design. The independent variable was method of measurement (Torg ratio and SAC). The dependent variables were Torg ratio and SAC scores.

SUBJECTS: Fourteen men (age = 24.4 +/- 2.5 years, height = 181.0 +/- 5.8 cm, weight = 90 +/- 13.5 kg) participated in this study. The C3 to C7 vertebrae were examined in each subject (n = 70).

MEASUREMENTS: The Torg ratio was determined by dividing the sagittal spinal-canal diameter by the corresponding sagittal vertebral-body diameter. The SAC was determined by subtracting the sagittal spinal-cord diameter from the corresponding sagittal spinal-canal diameter. The Torg ratio and SAC were measured in millimeters.

RESULTS: The SAC ranged from 2.5 to 10.4 mm and was greatest at C7 in 71% (10 of 14) of the subjects. The SAC was least at C3 or C5 in 71% (10 of 14) of the subjects. A Pearson product moment correlation revealed a significant relationship between the Torg ratio and SAC (r = .53, P < .01). Regression analyses revealed the vertebral body (r² = .58) accounted for more variability in the Torg ratio than the spinal canal (r² = .48). Also, the spinal canal (r² = .66) accounted for more variability in the SAC than the spinal cord (r² = .23).

CONCLUSIONS: The SAC measure relies more on the spinal canal compared with the Torg ratio and, therefore, may be a more effective indicator of spinal stenosis. This is relevant clinically because neurologic injury related to stenosis is a function of the spinal canal and the spinal cord (not the vertebral body). Further research must be done, however, to validate the SAC measure.

Document Type

Article

Publication Date

4-2002

Notes/Citation Information

Published in Journal of Athletic Training, v. 37, no. 2, p. 190-193.

Repository Citation

Tierney, Ryan T.; Maldjian, Catherine; Mattacola, Carl G.; Straub, Stephen J.; and Sitler, Michael R., "Cervical Spine Stenosis Measures in Normal Subjects" (2002). Physical Therapy Faculty Publications. 16.
https://uknowledge.uky.edu/rehabsci_facpub/16