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Degenerative Changes Following Spinal Fixation in a Small Animal Model

      Abstract

      Objective

      The objective of this study was to evaluate changes of the lumbar vertebral column following fixation.

      Design

      Using an established small animal (rat) model of spinal fixation (hypomobility), 3 contiguous lumbar segments (L4, L5, L6) were fixed with a specially engineered vertebral fixation device. Spinal segments of control rats were compared with those of animals with 1, 4, or 8 weeks of fixation. Subgroups of these fixation animals subsequently had the fixation device removed for 1, 2, 4, 8, or 12 weeks to evaluate the effects of attempting to reestablish normal forces to the vertebral segments following hypomobility.

      Setting

      This Institutional Animal Care and Use Committee (IACUC) approved study was conducted in a university animal facility.

      Animals

      Eighty-seven animals (23 controls animals and 64 fixation animals) were used in this study.

      Main Outcome Measures

      Outcome measures were degenerative changes of the vertebral bodies (VBs) and intervertebral disks (IVDs), zygapophysial (Z) joint osteophyte formation, and Z joint articular surface degeneration (ASD). Changes found in vertebral segments that were fixed (hypomobile) were compared with changes in adjacent nonfixed vertebral segments, and changes among fixation animals were compared with nonfixed controls.

      Main Results

      Very few degenerative changes were identified on the VBs and IVDs. Z joint changes were significant, both for osteophyte formation (analysis of variance [ANOVA], P < .0001) and ASD (ANOVA, P < .0001). Fixed segments had more degenerative changes than nonfixed segments for all Z joint parameters (ANOVA, P < .0001). Osteophyte formation and ASD were directly dependent on duration of fixation.

      Conclusions

      These findings indicate that fixation (hypomobility) results in time-dependent degenerative changes of the Z joints.

      Keywords

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      References

        • Janse J
        Principles and practice of chiropractic: an anthology. Kjellberg & Sons, Inc, Wheaton (IL)1976: 55
        • Mooney V
        • Robertson J
        The facet syndrome.
        Clin Orthop Res. 1976; 115: 149-156
        • Paris S
        Anatomy as related to function and pain. Symposium on evaluation and care of lumbar spine problems.
        Orthop Clin North Am. 1983; 14: 476-489
        • Cramer G
        • Tuck Jr, NR
        • Knudsen JT
        • Fonda SD
        • Schliesser JS
        • Fournier JT
        • et al.
        Effects of side posture positioning and side posture adjusting on the lumbar zygapophysial joints as evaluated by magnetic resonance imaging: a before and after study with randomization.
        J Manipulative Physiol Ther. 2000; 23: 380-394
        • Cramer GD
        • Gregerson DM
        • Knudsen JT
        • Hubbard BB
        • Ustas LM
        • Cantu JA
        The effects of side posture positioning and spinal adjusting on the lumbar z joints: a randomized controlled trial of 64 subjects.
        Spine. 2002; 27: 2459-2466
        • Sandoz R
        Some physical mechanisms and effects of spinal adjustments.
        Ann Swiss Chirop Assoc. 1976; 6: 91-141
        • Triano JJ
        Interaction of spinal biomechanics and physiology.
        in: Haldeman S Principles and practice of chiropractic. 2nd ed. Appleton & Lange, Norwalk (CT)1992: 225-257
      1. Goldstein M The research status of spinal manipulative therapy. US Department of Health, Education, and Welfare, Bethesda (MD)1975 (NINCDS monograph No. 15)
        • Brennan PC
        • Cramer GD
        • Kirstukas SJ
        • Cullum ME
        Basic science research in chiropractic: the state of the art and recommendations for a research agenda.
        J Manipulative Physiol Ther. 1997; 20: 150-168
        • Henderson CNR
        • Cramer GD
        • Zhang Q
        Development of a reversible small animal model of the chiropractic subluxation. Fifth World Federation of Chiropractic Congress; 1999 May 17-22; Auckland, New Zealand. World Federation of Chiropratic, Toronto1999: 140-141
        • Henderson CNR
        • DeVocht J
        • Kirstukas SJ
        • Cramer GD
        In vivo biomechanical assessment of a small animal model of the vertebral subluxation. Proceedings of the 2000 International Conference on Spinal Manipulation; 2000 September 21-23. FCER, Minneapolis, Minn. Des Moines2000: 193-195
        • Cramer G
        • Fournier JT
        • Henderson CNR
        Zygapophysial joint changes following spinal fixation. Proceedings of the 2000 International Conference on Spinal Manipulation; 2000 September 21-23. FCER, Minneapolis, Minn. Des Moines2000: 85-87
        • Ghadially F
        Fine structure of synovial joints. Butterworth and Company, Philadelphia1983: 280
        • Motulsky HJ
        Analyzing data with GraphPad Prism. GraphPad Software Inc, San Diego1999: 1-379
        • Engel R
        • Bogduk N
        The menisci of the lumbar Zygapophysial joints.
        J Anat. 1982; 135: 795-809
        • Giles LGF
        • Taylor JR
        Human Zygapophysial joint capsule and synovial fold innervation.
        Br J Rheumatol. 1987; 26: 93-98