Of course, low back pain (LBP) isn’t a diagnosis.  It’s a symptom, and a very non-specific (NS) symptom at that.  Unfortunately, the lumbar spine, with all its complexity, has a very limited vocabulary with which to express itself when some part of it is in trouble.  So LBP can be the result of many different pathologies for which there obviously is no single effective treatment.  Yet we keep conducting research trying to find the best treatment for the 85% or more with this NS symptom.

Let’s for a moment consider fever, which long ago was another NS symptom, but a very serious one.  For centuries, millions with a fever ended up dying, many during pandemics, many others as more isolated cases.  Many treatments were desperately tried hoping to save lives.  The breakthrough came when the microscope was invented that revealed microbes causing what became known as infection.  Culturing techniques and other diagnostic innovations eventually led to the accidental discovery of penicillin and other very effective antibiotics based on their specificity for each microbe.

If the scientists and physicians of that day had simply searched for the best treatment for NS fever, people would have continued dying. Instead, it was a breakthrough in diagnostics that led to saving millions of lives from infections.

What if people were dying from NS-LBP?  How long would we persist in searching for the best treatment for NS-LBP? Wouldn’t we be far more focused on learning something about its cause?

While many LBP treatments likely have value for some types of LBP, they are certainly not one-size-fits-all-treatments as they are commonly delivered and portrayed. Would abdominal or chest pain treatment be dictated primarily by the clinician the patient selects for care? Does every LBP patient simply look like a nail for the hammer(s) each clinician is trained to use?

Instead, as with fever, shouldn’t LBP researchers be focused on learning more about the cause of LBP? Unfortunately our best imaging technology has failed to help us find structural causes.  Knowing that, the Cochrane Back Review Group wrote in 1998: “There is urgent need for good ideas about how to identify homogeneous subgroups. The efficacy of interventions in the subgroups should be studied in randomized controlled trials.”(1)  Their “urgent need” was seventeen years ago!

Five years later, they wrote again: “systematic reviews on the efficacy of preventive and therapeutic interventions can never provide an adequate basis for clinical guidelines.  We clearly need additional systematic reviews of etiological, diagnostic, and prognostic studies.  Only then can the guidelines hope to offer an evidence-based answer to the “Holy Grail”-type questions, such as “which interventions are most effective for which patients?”(2)

Consider further two surveys (1998 and 2013) of international LBP researchers.(3, 4) Both reported that the #1 research priority was: “Can different varieties or subgroups of LBP be identified and, if they can, what criteria can be used to differentiate among them?” One listed twenty and the other twenty-five top research priorities.  The focus of most RCTs and LBP guidelines, i.e.“finding the best treatment for NS-LBP”, was of such low value to the responders that it didn’t appear on either list.

Little clinical research and no LBP clinical guidelines to date offer any insight into which interventions are most effective for which patients.  They contribute little or nothing to the quality of our decision-making when treating an individual with LBP. When will we get the message and shift our research focus?

Identifying and validating subgroups needs to become our top research focus.  But that requires more than RCTs. A new research paradigm(5) is needed that begins with reliability studies to demonstrate that both subgroup members and non-members can be reliably identified. A reliably identified subgroup then feeds subgroup-specific observational cohorts to identify potentially effective treatments.  Only then can the time, effort, and expense of conducting an RCT be justified in hopes of validating that subgroup by identifying a standardized, predictably effective treatment.

Ironically, guidelines have yet to acknowledge the considerable research over the past twenty-five years that has successfully identified and validated some LBP subgroups, most based on clusters of clinical findings. One with considerable support is the “derangement” subgroup in whom “pain centralization” and a “directional preference” are reliably elicited during a standardized baseline mechanical examination. Subgroup-specific observational cohorts, RCTs, and systematic reviews have validated this mechanical diagnosis. But these studies are routinely overlooked by most clinicians, researchers, and every guideline-to-date, constrained by their tunnel vision on finding the best treatment for NS-LBP.

What a great concept: matching treatments to individual patient characteristics!! Sorta like selecting an antibiotic for a specific microbe instead of treating a fever with blood letting.

Of course, for every validated LBP subgroup, the percentage considered to have NS-LBP decreases…..and that’s a good thing.  So why do funders keep funding RCTs focused on NS-LBP?  It was Einstein who defined insanity as “doing the same thing over and over again and expecting different results.”

In summary, it’s deeply troubling that 1-our lack of progress in solving LBP, 2-the large numbers who are disabled by low back conditions, and 3-the increasing amount we spend each year for ineffective care, are insufficient motivation to bring change in either the conventional LBP research paradigm or the focus of clinical guidelines.

How quickly would we change our research focus if people were dying from LBP?

References
1. Bouter L, van Tulder M, Koes B. Methodologic issues in low back pain research in primary care. Spine. 1998;23(18):2014-20.
2. Bouter L, Pennick V, Bombardier C. Cochrane back review group. Spine. 2003;28(12):1215-8.
3. Borkan J, Koes B, Reis S, Cherkin D. A report from the second international forum for primary care research on low back pain:  reexamining priorities. Spine. 1998;23(18):1992-6.
4. Costa L, Koes B, Pransky P, Borkan J, Maher C, Smeets R. Primary care research priorities in low back pain: an update. Spine. 2013;38:148–56.
5. Spratt K. Statistical relevance. In: D.F. Fardon ea, Editors, editor. Orthopaedic Knowledge Update: Spine 2. 2nd ed. Rosemont, Illinois: The American Academy of Orthopaedic Surgeons; 2002. p. 497-505.

Please share your thoughts with me and ask whatever questions come to mind.

I wrote in my last posting that published data document that the current U.S. system of spine care appears to be actually accelerating the development of chronic pain, work disability, narcotic addiction, use of injections and surgery, and guideline-discordant care in general. Sky-rocketing costs tied to increased utilization of unproven invasive procedures and devices have produced little, if any, evidence of any improvement in patient outcomes. The growing use of MRIs generates misdiagnoses while more opioid prescriptions lead to more addiction.

This decline in quality and rise in cost is directly related to ineffective guidelines that stem from 100’s of RCTs of variable quality that all focus on the study population with non-specific (NS) LBP. The very best these RCTs and guidelines can produce is to determine the best treatment for the average patient with this non-specific symptom. Is it any wonder that guidelines conclude that the best treatment is completely non-specific, one-size-fits-all, specifically encouraging everyone to return to activity ASAP and to reassure that this self-care strategy is likely to result in recovery at some point?

Einstein defined insanity as doing the same thing over and over again and expecting different results. If we change nothing and persist in studying NS-LBP rather than making some diagnostic progress, we will learn nothing new.  We will spend another 25 years learning how to best treat the average patient with this NS symptom.

Two published surveys of international LBP researchers, published in 1998 and 2012, both reported the identification and validation of LBP subgroups as the #1 research priority. There is an urgent need to find ways of identifying or characterizing individuals’ actual underlying disorder and treating that, rather than just a NS symptom. That requires identifying diagnostic subgroups.

Kevin Spratt, Ph.D., an eminent spine researcher at Dartmouth Medical Center in New Hampshire, wrote in 2003 about a research strategy intended to identify and validate subgroups. He referred to his paradigm as the “A-D-T-O” research model. A-D-T-O stands for Assessment – Diagnosis – Treatment – Outcome. Just as A-D-T-O represents the conventional order of clinical care of individual patients, Spratt wrote that it should also be the order for investigating and identifying the best treatments for clinical subgroups.

He points out that these four A-D-T-O pillars are connected by three research links. Establishing the A-D link is where the research effort must begin.  This fundamental link requires conducting inter-examiner reliability studies focused on the assessment process-of-interest in an effort to distinguish between those who are members of a diagnostic subgroup and those that aren’t.  Any further research targeting a subgroup cannot be justified if its members and non-members cannot first be reliably identified.

Only after this A-D link is established can the D-T link utilize observational cohort studies focused on members of this subgroup to determine if improved outcomes can be produced with a single treatment. Can data be generated that indicates that this subgroup has a favorable prognosis if treated in a specific way or ways?

Once the A-D and D-T links have been established, the third and final link seeks to determine the best treatment for this reliably identified subgroup. Only now are randomized clinical trials (RCTs) justified to compare treatments previously identified as promising as a result of the prior D-T studies. Substantially improved outcomes with any treatment are required, i.e. the only way, to validate that subgroup.

Any subgroup validated by outcomes can now be subtracted from that very large NS-LBP subgroup.  In the case of one very large subgroup that has substantial evidence in all three of the A-D-T-O links, this large NS-LBP black box is now significantly diminished.  That subgroup is the one whose members’ pain can be centralized/abolished with a directional preference. This subgroup carries a ‘patho-mechanical’ diagnosis of ‘reducible derangement’ where a patho-anatomic diagnosis is not always possible. I’ve talked about that subgroup a great deal in prior blog posts and will be doing so soon again.  Most spine stakeholders are unaware of this evidence, this subgroup, and this A-D-T-O research paradigm.

This A-D-T-O research model is simple, straight-forward, and focuses on moving spine care toward patient-specific treatments. Because it is either unfamiliar to most LBP clinical researchers, or is viewed as too disruptive from the current research convention of conducting high-quality RCTs that target the best treatment for NS-LBP, it is not in wide use yet. Studies that do comply with this new research paradigm have consequently been ignored by clinical guideline panels that are fixated on the high value of RCTs with little regard for the limitations of continuing to focus on NS-LBP.

The A-D-T-O model should be the basis for future clinical research for any disorder, particularly one characterized by a non-specific symptom. Health care clearly needs to shift its attention toward individualized care and that requires a shift in the overall research paradigm.  We should not waste more time and money conducting RCTs of NS-LBP that, over the past several decades, have produced only one-size-fits-all non-specific care that is not improving either the quality or cost of spine care.

I welcome feedback and questions.  Please be sure to click on “Like” if this was useful and enlightening, or “Leave a Comment” by clicking on “Comment” below.  Have a wonderful week everyone.

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