The Effects of Age on the Morphometry of the Cervical Spinal Cord and Spinal Column in Adult Rats: An MRI-Based Study

Authors

  • Andrew C. Laing,

    Corresponding author
    1. Injury Biomechanics and Aging Laboratory, Department of Kinesiology, University of Waterloo, 200 University Ave West, Waterloo, Ontario, Canada
    2. International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada
    • Correspondence to: Andrew Laing; Department of Kinesiology, University of Waterloo, 200 University Ave, West, Waterloo, ON N2L 3G1, Canada. E-mail: actlaing@uwaterloo.ca

    Search for more papers by this author
  • Elora C. Brenneman,

    1. Injury Biomechanics and Aging Laboratory, Department of Kinesiology, University of Waterloo, 200 University Ave West, Waterloo, Ontario, Canada
    Search for more papers by this author
  • Andrew Yung,

    1. MRI Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
    Search for more papers by this author
  • Jie liu,

    1. International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada
    Search for more papers by this author
  • Piotr Kozlowski,

    1. International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada
    2. MRI Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
    Search for more papers by this author
  • Thomas Oxland

    1. International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada
    2. Orthopaedics and Injury Biomechanics Group, Departments of Orthopaedics and Mechanical Engineering, University of British Columbia, Vancouver, British Columbia, Canada
    Search for more papers by this author

ABSTRACT

Rat models are commonly used to investigate the pathophysiological pathways and treatment outcomes after spinal cord injury (SCI). The high incidence of fall-induced SCI in older adults has created a need for aging models of SCI in rats to investigate potential age-related differences in SCI severity and outcomes. The aims of this study were to determine the influences of age and vertebral level on the geometries of the cervical spinal cord and spinal column in a rat model. Three young (3 months) and three aged (12 months) Fischer 344 rats were imaged in a high field (7 T) small-animal magnetic resonance imaging system. All spinal cord geometry variables (including depth, width, and axial cross-sectional area) and one spinal canal variable (depth) were significantly larger in the aged specimens by an average of 8.1%. There were main effects of vertebral level on all spinal cord variables and four spinal canal variables with values generally larger at C4 as compared to C6 (average increases ranged from 5.7% to 12.9% in spinal cord measures and 5.4% to 6.8% in spinal canal measures). High inter-rater reliability between two measurers was observed with a mean intraclass correlation of 0.921 and percent difference of 0.9% across all variables measured. This study clearly demonstrates that cervical spinal cord geometry changes between the ages of 3 and 12 months in Fischer 344 rats. This information can aid in the planning and interpretation of studies that use a rat model to investigate the influence of age on cervical SCI. Anat Rec, 297:1885–1895, 2014. © 2014 Wiley Periodicals, Inc.

Ancillary