Journal of Manipulative and Physiological Therapeutics
Volume 29, Issue 1 , Pages 89-90, January 2006

Distraction Manipulation of the Lumbar Spine: A Review of the Literature

Fort Wayne, IN, USA

Article Outline

 

To the Editor:

Gay et al1 discussed nucleus pulposus movement during flexion and extension of the lumbar spine, citing Fennell et al2 as stating that the nucleus moves anterior on extension and posterior on flexion. Full study of the Fennell paper, however, shows a different finding. Fennell studied nuclear motion on magnetic resonance imaging of 3 patients—1 normal 18-year-old patient with no history of low back pain and two 25- and 46-year-old patients with low back pain history.

The 18-year-old patient with no back pain did show anterior nuclear movement on extension and posterior motion on flexion; however, the 2 patients with a history of low back pain showed the L4-L5 disk to move anteriorly during flexion. The nucleus spread within the L4-L5 disk during flexion instead of migrating posteriorly. Fennel explained the 2 unexpected results in the painful spines as possible disk degeneration etiology.

Gay et al1 also discussed the study of Beattie et al3 about 20 healthy young women with lumbar spine magnetic resonance imaging in extension, and Gay et al stated that they found that the posterior margin of the nucleus in the normal lower lumbar disk tends to move anteriorly with extension and posteriorly with flexion, and there was no anterior nucleus movement. Again, that is not a complete explanation of Beattie's finding. He found that in normal disks without degeneration, the posterior disk margin increased between the posterior margin of the nucleus pulposus and the posterior portion of the vertebral bodies of the normal disks of healthy young females during extension motion. However, 8 of the 20 subjects had at least one degenerative disk in the lower lumbar spine. The nucleus of the degenerative disks did not move the same as normal disks. Degenerative disks deform differently from nondegenerative disks. Other similar studies have shown that the nucleus pulposus moves posterior or does not move with extension movement.4, 5, 6, 7 Reading the article of Gay et al., one is led to believe that the nucleus pulposus always moves anterior on extension and posterior on flexion, when in fact that is not the case. Gay et al accurately cite literature showing that stenosis is induced into the vertebral and the osseoligamentous canals by extension, which causes posterior annulus protrusion, ligamentum flavum buckling, facet imbrication, and narrowing of the posterior disk space.

Hopefully, I have augmented the findings as given in the important paper of Gay et al. The movement of the nucleus pulposus is unpredictable in the degenerated disk. As chiropractors, we treat degenerated disks and need to be aware of their behavior. The intervertebral disk is probably the most common source of chronic low back pain.8 Tolerance testing before applying manipulation to the patient's spine is prudent because of the unpredictable nature of the disk. For safety, I teach that the maximum angle of flexion used is 6° when long y-axis decompression is applied to the motion segment. At that degree, our research has shown that the ligament stresses are well within normal limits so that damage will not occur to the stability of the segments. This small 6° flexion angle used may diminish the value of this discussion, but nevertheless, we must maintain correct biomechanical concepts for future study.

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References 

  1. Gay RE, Bronfort G, Evans RL. Distraction manipulation of the lumbar spine: a review of the literature. J Manipulative Physiol Ther. 2005;28:266–273
  2. Fennell AJ, Jones AP, Hukins DWL. Migration of the nucleus pulposus within the intervertebral disc during flexion and extension of the spine. Spine. 1996;21:2753–2757
  3. Beattie PF, Brooks WM, Rothstein JM, Sibbitt WL, Roberts RA, MacLean T, et al. Effect of lordosis on the position of the nucleus pulposus in supine subjects: a study using magnetic resonance imaging. Spine. 1994;19:2096–2102
  4. Vanharanta H, Ohnmeiss D, Stith W, Rashbaum R, Hochschuler S, Guyer R. et al. Effect of repeated trunk extension and flexion movements as seen by CT/discography orthopedic transactions. Journal of Bone and Joint Surgery 10 Shattuck Street, Boston, Massachusetts, 12115/Volume XIII, Number 1,1987, pg 28. Poster Exhibit, North American Spine Society, Banff, Canada, June, 1987.
  5. Gill K, Videman T, Shimizu T, Mooney V. The effect of repeated extensions on the discographic dye patterns in cadaver lumbar motion segments. Clin Biomech. 1987;2:205–210
  6. Roaf R. A study of the mechanics of spinal injuries. J Bone Joint Surg. 1960;42B:810
  7. Schultz AB, Warwick DN, Berkson MH, Nachemson AL. Mechanical properties of human lumbar spine segments. Part 1. Response in flexion, extension, lateral bending and torsion. J Biomech Eng. 1979;101:46–52
  8. Kuslich SD, Ulstrom CL, Michael CJ. The tissue origin of low back pain and sciatica. Orthop Clin North Am. 1991;22:181–187

PII: S0161-4754(05)00326-X

doi:10.1016/j.jmpt.2005.10.003

Journal of Manipulative and Physiological Therapeutics
Volume 29, Issue 1 , Pages 89-90, January 2006

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