If you’ve ever had neck or back pain, you know that your immediate concern is often how long is this going to last? Or maybe even will I ever get better? Researchers are busy trying to figure out the many pieces to the puzzle presented by spine pain.
In this systematic review, rehabilitation specialists look to see if there’s any evidence that the examiner can predict the final outcome based on symptoms observed during the exam. And secondly, they ask the question: is it possible to tell how well patients will respond to treatment based on how their pain responds to conservative (nonoperative) care?
One particular testing and treatment approach is the focus of this study and that’s Robin McKenzie’s idea that if the pain location or intensity changes, it is possible to predict a favorable or unfavorable response to treatment using McKenzie principles. McKenzie’s movement testing called centralization requires the patient to move in a prescribed direction repeatedly. If the pain retreats from down the arm or down the leg to a central spot in the spine, this is a sign that specific movements can be used to treat the problem.
Many physical therapists subscribe to this theory and are trained in the McKenzie technique. But there hasn’t been enough evidence so far to prove the technique is a reliable predictor of long-term results. And the results of this review of the studies published to date confirmed that evidence is still very limited to support the idea that symptoms changed by repeated spinal movements point to a positive prognosis.
The review was conducted by searching major medical databases for all years available up to March 2007. Of the 4,249 possible articles containing information on spinal pain, symptom responses, and prognosis, only 22 articles had all the data of importance to this study.
All 22 articles were carefully reviewed and analyzed. The authors present the information from all of the studies in table form with columns summarizing variables from each study for comparison. For example, each article was scored to provide an idea of how high the quality of the research was. Other descriptive data included length of time for follow-up (since long-term outcomes were of interest), symptom responses to testing and treatment, and details about how soon/how often patients returned-to-work.
Patient characteristics such as history of neck or back pain, activity level, socioeconomic variables, and type of treatment program used were also recorded in the table. And finally, measurable outcomes using pain, range-of-motion, and function or disability were reported.
Quite literally, the results were all over the map. Patients’ symptoms responded to testing but not with any consistency from one test to another. And there was a wide range of patient responses no matter what type of testing was done (e.g., movement testing, spinal compression or distraction, neurodynamic tests of nerve mobility, tests for spinal instability).
Sometimes the patient’s responses varied from one session to the next using the same test procedures. Studies just didn’t show a consistent symptom response to McKenzie’s principles of centralization and directional preference. Directional preference refers to movements in a particular direction (flexion, extension, rotation, side bending) that reduce symptoms.
There just isn’t enough evidence that using these symptom responses as a prognostic factor of outcomes is a valid or reliable approach. The authors are clear about saying that these results don’t necessarily mean the McKenzie principles are NOT predictive. It’s more the case that better research with high quality methods are needed to investigate this approach.
Finding patient factors that can predict what will happen is a high priority among neck and back pain researchers. Understandably, patients would like to know: How serious is my condition? What do my symptoms mean? How soon can I get back to work? Finding ways to predict the answers to these questions and figuring out what kind of treatment works best for each type of problem remains to be discovered.