Neck pain is a monster we know well in the world of chiropractic. Long before a person understands or experiences the power of chiropractic for the broader aspects of health, neck pain is up there with back pain as a highly visible benefit of chiropractic care. It is, of course, the fourth highest cause of disability globally. While this statistic isn’t likely to change any time soon, we do know a couple of things: chiropractic can help, and neck pain is more important than most people know.
What is sensorimotor dysfunction exactly? As we know, the brain needs to process a whole lot of signals and information in order for the body to move. This includes sensory information from the body and motor instructions from the brain (which is an extreme oversimplification of a complicated process). When something like neck pain or back pain enters the picture, it disrupts or distorts these messages leading not just to pain but to altered processing.
This is where sensorimotor dysfunction enters the picture. Here, normal processing and integration of sensory information is disrupted, leading to (among other things) issues with motor control. This might not be something earth-shattering like an acquired brain injury or neurological condition, but simply planning and execution of movement, clumsiness, and balance – all of these things rely on sensorimotor integration.
Recently, a new study emerged, scrutinising the impact of chiropractic care in individuals with neck pain. The specific mechanisms researchers were examining were sensory-motor dysfunction. The pilot study, published in the journal of Brain Sciences, had a simple aim in mind – marrying up patient-reported outcomes with research findings when it came to chiropractic care for neck pain and its influence on sensory-motor dysfunction. Why? We had studied metrics that were meaningful to scientists- things like how subclinical neck pain and subsequent chiropractic care might influence various aspects of pain, mobility, nervous system and brain function- but we hadn’t asked patients what they experienced and noticed before and after care.
The method was simple: a questionnaire was administered to a group of people with and without chronic neck pain or subclinical neck pain. Given the nature of the study, they did know which group they belonged to, so it was not possible for this study to be blinded. The study was a pilot study, too, as it examined whether or not it was possible to identify and quantify changes in sensory-motor integration following a treatment plan.
This meant that researchers had to consider biases in the study’s design and rollout, but it also meant that, should the study find that the questionnaire could draw out such data, it would be a helpful research methodology for more than this pilot study alone.
The questionnaire was administered to thirty pain-free patients and thirty neck pain patients (thirteen of whom had chronic neck pain and seventeen of whom had subclinical neck pain – which is mild to moderate pain they had not sought treatment for) Then, the subclinical neck pain patients received eight weeks of chiropractic care, and the chronic pain patients received twelve weeks of care, at which point they undertook the survey again.
There were a number of metrics that were used for the study. The first was simply the neck disability index, which is often used in research and in clinical practice. The Von Korff Chronic Pain Grade Scale was also used to situate a person on a scale of pain and disability for the last six months. The validity of either of these tests was not in question. Rather, the Sensory-motor Dysfunction questionnaire was under the proverbial microscope.
This Questionnaire was created for people with chronic or recurrent spinal pain and designed to determine the degree to which this altered spinal function may be affecting their central processing and therefore their lives. It is a 12-item questionnaire with four options on every question, ranging from “Never – 0” to “Most or all of the time – 3”.
What did the study find?
In this pilot study, twenty-two of the original pain-group participants finished the study and all of them completed the entire questionnaire. Eight of them were chronic pain patients and the rest were from the subclinical pain group. As expected, bigger differences were noted in the chronic pain group, who reported a significant reduction in sensorimotor dysfunction. This equated to a medium effect size of almost 50% reduction in symptoms.
The subclinical neck pain group had only small effect. However, due to the size of the sample and the differences in treatment time, a much larger sample size was needed to be able to establish effect sizes.
Essentially, the questionnaire was found to be robust enough to discriminate between healthy and neck-pain patients, and is likely sensitive enough to show treatment effects. However, the sample size wasn’t big enough to discriminate effects between groups. This isn’t a negative finding! Rather, it shows us that larger studies need to be done to nail down the differences between the subclinical neck pain group and the chronic neck pain group.
An interesting indication that we see from this study is that the body schema appears to be able to recalibrate relatively quickly. Researchers remarked that the total questionnaire score for the combined chronic neck pain and subclinical neck pain groups decreased following treatment, “which is consistent with the findings of positive changes in [Sensorimotor integration] with respect to chiropractic treatment physiotherapy or massage therapy. This questionnaire appears to capture the recalibration of the body schema in response to treatment, which is adjusted within days or weeks. This is reflected by a large effect size with respect to time and large SRM value, suggesting that the [questionnaire] may be sensitive to quantify changes in [sensorimotor integration] previously measured in these laboratory-based studies.
The large decrease in [questionnaire] scores within the chronic neck pain group is consistent with past studies that demonstrated improvements in sensorimotor function and central processing following 12 weeks of treatment. In contrast, the minuscule decrease in score with the subclinical neck pain group does not coincide with past work, suggesting that 4 to 6 weeks is sufficient to induce changes in sensorimotor function.”
This shows us that some variables may need to be adjusted in future research, and a larger study needs to follow this pilot. But we can see that chiropractic care for chronic neck pain was notable in terms of sensorimotor changes in this pilot. We can’t wait to see what the next study shows in terms of confirming this so we can generalise it to the wider population, and so we can see what’s going on in the subclinical neck pain group.
Its one thing for researchers to see changes on brain scans and in muscle impulses, its another thing for chiropractors to see functional and neurological changes in the practice, but it’s the experience of the person under care that brings this full circle. And its here that we want to make our biggest impact.
Stay tuned for more!
Ambalavanar, Ushani, McIntosh, Megan, Haavik, Heidi, Murphy, Bernadette (2024)
Known-Group Validity and Sensitivity to Change in the Sensory-Motor Dysfunction Questionnaire in Individuals with Neck Pain: A Pilot Study, vol. 14 Brain Sciences
DOI – 10.3390/brainsci14111050 https://www.researchgate.net/publication/385192302_Known-Group_Validity_and_Sensitivity_to_Change_in_the_Sensory-Motor_Dysfunction_Questionnaire_in_Individuals_with_Neck_Pain_A_Pilot_Study/citation/download
