In the United States, low back pain has reached epidemic proportions and represents a significant threat to the public health of its citizens [1].  Previous estimates as to the total annual cost of low back pain in the United States have ranged from $20 to $50 billion [1, 2].  More recent opinions have placed the figure at between $100 to $200 billion per annum [3].  A closer evaluation of low back pain’s economic impact reveals that it is the number one reason for individuals under the age of 45 to limit their activity [4, 5], number two complaint seen in physician’s offices [6], the third leading cause for surgery and the fifth most common requirement for hospitalization [7].

While the economic consequences of low back pain are quite apparent, the same cannot be said for many of its conservative treatment options.  Many forms of treatment have demonstrated conflicting results in the literature.  One example is spinal manipulative therapy, a common treatment of low back pain which has shown promise in a number of randomized clinical trials [8-11].  Conversely, other studies have revealed spinal manipulative therapy to have equivocal outcomes in comparison to other forms of treatment [12-15].  One of the theories as to this discrepancy is the inability to recognize a priori, those patients with low back pain who are most likely to benefit from spinal manipulative therapy [12, 16, 17].  In other words, low back pain is a condition which tends to be studied as though the etiology of pain is of a common source.  As a result, spinal manipulative therapy has been evaluated as a therapy applied to this heterogeneous population. This may have resulted in a dilution of its clinical outcomes as reflected in the small effect sizes observed in such studies. 

This observation lead researchers to pursue the development [18] and validation [10] of a clinical prediction rule for the identification of the sub-group of patients with low back pain who are likely to experience sustained decreases in both pain and disability following the application of spinal manipulative therapy.  This body of work has identified several key characteristics of patients suffering from low back pain which can be used to predict a favorable response to spinal manipulative therapy (duration of current episode of low back pain of less than 16 days.):

1. Not having symptoms distal to the knee.
   
2. Fear avoidance beliefs questionnaire work subscale score of less than 19 points.
   
3. One or more hypomobile lumbar segments present on manual evaluation.
   
4. At least one hip with greater than 35 degrees of internal rotation range of motion.

Clinical behavior within the chiropractic profession has utilized spinal manipulative therapy in the same fashion as the research community has traditionally evaluated its application.  Often times, chiropractors view this treatment approach as a panacea for all types of low back pain and apply it as a monotherapy or in combination with other conservative treatments.  As a result, the same dilution effect of treatment outcomes can be observed.  If chiropractors were to recognize the uniqueness of presentation in the low back pain population, their clinical decision making and outcomes would improve.  By sub-grouping low back pain patients based on their demographic and physical examination findings, the most efficacious treatment option can be selected; thus yielding a more streamlined approach to the benefit of the patient, provider and healthcare system as a whole.

As field practitioners, researchers, educators and members of APHA, the recently developed clinical prediction rule for manipulation should alter the looking glass by which we view patients with low back pain.  Instead of viewing this patient population as a homogenous group suffering from a pain based on its location, they should be viewed as individuals with a unique functional deficit, some of whom will likely respond well to spinal manipulative therapy.  For those patients who do not fit this criterion, it is important that we also recognize the necessity of stabilization or directional preference exercise, traction therapy or referral for more invasive treatment options.  Preliminary work on a clinical prediction rule for stabilization exercise has already been accomplished [19] and there are future plans to further evaluate the role of centralization exercise and traction therapy.

While there is still much work to be done in this area of study, these initial findings represent encouraging accomplishments in the ongoing effort of evaluating conservative interventions for low back pain. This line of research also signifies a tremendous opportunity for chiropractors to improve their clinical outcomes and further contribute to the improved state of public health in the United States and abroad.

1.  Deyo, R.A., Low-back pain. Sci Am, 1998. 279(2): p. 48-53.

2.  Nachemson, A.L., Newest knowledge of low back pain. A critical look. Clin Orthop Relat Res, 1992(279): p. 8-20.

3.  Katz, J.N., Lumbar disc disorders and low-back pain: socioeconomic factors and consequences. J Bone Joint Surg Am, 2006. 88 Suppl 2: p. 21-4.

4.  Lively, M.W., Sports medicine approach to low back pain. South Med J, 2002. 95(6): p. 642-6.

5.  Bratton, R.L., Assessment and management of acute low back pain. Am Fam Physician, 1999. 60(8): p. 2299-308.

6.  Deyo, R.A. and W.R. Phillips, Low back pain. A primary care challenge. Spine, 1996. 21(24): p. 2826-32.

Pai, S. and L.J. Sundaram, Low back pain: an economic assessment in the United States. Orthop Clin North Am, 2004. 35(1): p. 1-5.

7.  United Kingdom back pain exercise and manipulation (UK BEAM) randomised trial: effectiveness of physical treatments for back pain in primary care. Bmj, 2004. 329(7479): p. 1377.

8.  Aure, O.F., J.H. Nilsen, and O. Vasseljen, Manual therapy and exercise therapy in patients with chronic low back pain: a randomized, controlled trial with 1-year follow-up. Spine, 2003. 28(6): p. 525-31; discussion 531-2.

9.  Childs, J.D., J.M. Fritz, T.W. Flynn, et al., A clinical prediction rule to identify patients with low back pain most likely to benefit from spinal manipulation: a validation study. Ann Intern Med, 2004. 141(12): p. 920-8.

10. Giles, L.G. and R. Muller, Chronic spinal pain: a randomized clinical trial comparing medication, acupuncture, and spinal manipulation. Spine, 2003. 28(14): p. 1490-502; discussion 1502-3.

11. Assendelft, W.J., S.C. Morton, E.I. Yu, et al., Spinal manipulative therapy for low back pain. A meta-analysis of effectiveness relative to other therapies. Ann Intern Med, 2003. 138(11): p. 871-81.

12. Assendelft, W.J., S.C. Morton, E.I. Yu, et al., Spinal manipulative therapy for low back pain. Cochrane Database Syst Rev, 2004(1): p. CD000447.

13. Assendelft, W.J., S.C. Morton, E.I. Yu, et al., Spinal manipulative therapy for low back pain. Cochrane Database Syst Rev, 2004(1): p. CD000447.

14. Cherkin, D.C., K.J. Sherman, R.A. Deyo, et al., A review of the evidence for the effectiveness, safety, and cost of acupuncture, massage therapy, and spinal manipulation for back pain. Ann Intern Med, 2003. 138(11): p. 898-906.

15. Ernst, E. and P.H. Canter, A systematic review of systematic reviews of spinal manipulation. J R Soc Med, 2006. 99(4): p. 192-6.

16. Borkan, J.M. and D.C. Cherkin, An agenda for primary care research on low back pain. Spine, 1996. 21(24): p. 2880-4.

17. Bouter, L.M., M.W. van Tulder, and B.W. Koes, Methodologic issues in low back pain research in primary care. Spine, 1998. 23(18): p. 2014-20.

18. Flynn, T., J. Fritz, J. Whitman, et al., A clinical prediction rule for classifying patients with low back pain who demonstrate short-term improvement with spinal manipulation. Spine, 2002. 27(24): p. 2835-43.

19. Hicks, G.E., J.M. Fritz, A. Delitto, et al., Preliminary development of a clinical prediction rule for determining which patients with low back pain will respond to a stabilization exercise program. Arch Phys Med Rehabil, 2005. 86(9): p. 1753-62.