Study Design. Clinical literature consistently identifies women as more susceptible to trauma-related neck pain, commonly resulting from soft tissue cervical spine injury. Structural gender differences may explain altered response to dynamic loading in women leading to increased soft tissue distortion and greater injury susceptibility.
Objective. Identify anatomic gender differences in cervical spinal geometry that contribute to decreased column stability in women.
Summary of Background Data. Previous studies investigating male and female vertebral and vertebral body geometry demonstrated female vertebral dimensions were smaller. However, populations were not size matched and parameters related to biomechanical stability were not reported.
Methods. Computed tomography scans of the cervical spine were obtained from size-matched young healthy volunteers. Geometrical dimensions were obtained at the C4 level and analysis of variance determined significant gender differences.
Results. Two volunteer subsets were size matched based on sitting height and head circumference. All geometrical measures were greater in men for both subsets. Vertebral width and disc-facet depth were significantly greater in men. Additionally, segmental support area, combining interfacet width and disc-facet depth, was greater in men, indicating more stable intervertebral coupling.
Conclusion. Present results of decreased linear and areal cervical dimensions leading to decreased column stability may partially explain increased traumatic injury rates in women.
The purpose was to identify anatomic gender differences in cervical geometry contributing to column stability. Analysis of CT scans from size-matched males and females demonstrated smaller linear and areal dimensions in women. Smaller support area contributes to decreased column stability and could partially explain increased trauma-related neck pain in women.
From the *Department of Neurosurgery, Medical College of Wisconsin; †Department of Veterans Affairs Medical Center, Milwaukee, WI; and ‡Naval Air Systems Command, Patuxent River, MD.
Acknowledgment date: February 26, 2007. First revision date: May 2, 2007. Second revision date: June 8, 2007. Third revision date: July 5, 2007. Acceptance date: September 10, 2007.
The manuscript submitted does not contain information about medical device(s)/drug(s).
Federal funds were received in support of this work. No benefits in any form have been or will be received from a commercial party related directly or indirectly to the subject of this manuscript.
Supported in part by the Office of Naval Research through Naval Air Warfare Center Division contract N00421-02-C-3005 and the Department of Veterans Affairs Medical Research.
Address correspondence and reprint requests to Brian D. Stemper, PhD, Department of Neurosurgery, Medical College of Wisconsin, 9200 West Wisconsin Ave., Milwaukee, WI 53226; E-mail: firstname.lastname@example.org