Autoimmune disorders are a broad family of illnesses and syndromes, and their management is a serious issue for consideration as the pain and inflammation that comes with the disorders is ongoing in its nature. Thus, when a new study comes out looking at neurodynamic interventions for Multiple Sclerosis (delivered via manual therapy), we are all ears. A new randomised controlled trial has looked at this very issue and the results are quite promising.
While our familiarity with Multiple Sclerosis continues to increase, the pathogenesis or cause of the disease remains unclear. What we know is this: Multiple Sclerosis (MS) is characterised by central nervous system (CNS) lesions that affect physical, cognitive, and neurological function. As is the case with most complex diseases, the development of this condition is impacted by many different factors including genetic predisposition and exposure to environmental factors and stressors such as infectious agents, vitamin deficiencies, and smoking among many potential others. The interaction of these factors triggers an injurious inflammatory response resulting in demyelination of nerves and neuronal death and dysfunction [1].
What does demyelination mean? Essentially, our nerves are wrapped in a protective sheath that ensures that our neuronal impulses reach their destination and do so as quickly as they need to. When this sheath breaks down, these messages slow down, distort or stop leaving many potential deficits in their wake. Think of it as driving at 100 kilometres per hour down a beautifully smooth, asphalted road versus driving at 100 kilometres per hour down a road full of potholes.
One is absolutely going to be more uncomfortable or even catastrophic than the other.
Conventional pharmacologic treatments for MS are focused on decreasing the inflammation to diminish further neuronal damage. It is to be expected that pain is experienced by most patients with MS and is often one the worst secondary symptoms individuals suffer from. As we know, pain can be incredibly debilitating, impacting all areas of life, and although both pharmacological and non-pharmacological interventions have been proposed, their efficacy in controlling pain is discouraging.
Here at ASRF we have spoken a lot about non-invasive, and non-pharmacological interventions and the hope they provide individuals with limited options to alleviate symptoms. In a recent randomised clinical trial MS has been added to the list of conditions that manual therapy may be able to significantly impact, particularly on the pain front [2]. While the study didn’t reference chiropractic care in particular, its potential to carry across into the manual therapy offered by chiropractors (in the form of the chiropractic adjustment) is quite significant.
The current understanding of the mechanisms underlying the pain experienced by individuals with MS remains vague, but it is thought that the changes to the functioning of the nervous system caused by damage may result in disinhibition of descending pain pathways and an imbalance of afferent inputs and contribute to the pain experience. Overall, the aim of a manual therapy intervention (such as chiropractic care) is to decrease central nervous sensitivity to counteract the theorised state of hyper-excitability caused by increased neuronal activity at both the sites of injury and remote sites.
The current study involved two randomly assigned groups of 32 patients with MS [2]. Both groups received the usual care and 5 sessions of multimodal management of 30-minute duration, twice a week. The treatment was based on strength exercises, soft tissue mobilisation, and muscle stretching exercises. The experimental group also received bilateral (both sides of the body) neurodynamic slider intervention that targeted the median, ulnar, and radial nerves. The speed, amplitude, and combination of the movements were adjusted by the therapist depending on tissue resistance and to prevent producing pain symptoms during the technique.
The primary outcomes focused on during the study was sensitivity to pressure pain assessed by pressure pain thresholds. Other outcomes included upper extremity pain intensity, light touch detection threshold, and manual dexterity of patients.
There was a significant difference between baseline and follow-up results for pressure pain sensitivity between the two groups, specifically over the ulnar nerves and second metacarpal but not for the median or radial nerves or the tibialis anterior muscle. Overall, the experimental group showed a greater bilateral increase in pressure pain thresholds compared to the control group.
Similarly, the group receiving the additional neurodynamic intervention experienced a greater decrease in pain intensity at rest than the control group. For the light touch and manual dexterity outcomes the experimental group again showed a greater decrease in light touch sensitivity and a greater unilateral increase in dexterity following treatment than the alternate group. Of particular interest was the distinction seen between patients with secondary progressive and relapsing-remitting types of MS and those with primary progressive type of MS within the experimental group. Patients of the former characteristics demonstrated greater increases on manual dexterity after treatment than those patients with primary progressive type of MS.
While the study is promising, it is also logical and appears to line up with other studies we have seen which indicated that chiropractic and other manual therapies may have an impact on neurological pain signatures, pressure pain thresholds and more, not to mention the case reports in existence where individuals have reported improvements concomitant with chiropractic care [3-5].
All in all, anything that improves the nervous system function and quality of life of Multiple Sclerosis Sufferers is music to our ears. We look forward to more studies focused specifically on chiropractic interventions, but this is a promising start indeed.
REFERENCES:
- Ghasemi N, Razavi S, Nikzad E. Multiple Sclerosis: Pathogenesis, Symptoms, Diagnoses and Cell-Based Therapy. Cell journal. 2017. 19(1):1–10.
- Pérez-Bruzón J de D, Fernández-de-las-Peñas C, Cleland JA, Plaza-Manzano G, Ortega-Santiago R. Effects of Neurodynamic Interventions on Pain Sensitivity and Function in Patients with Multiple Sclerosis: A Randomized Clinical Trial. Physiotherapy. 2021.
- Shackleton E, Toutt C, and Edwards D (2019), “Pscyhological Context Effects of Participant Expectation on Pain Pressure Thresholds as an Adjunct to Cervicothoracic HVLA Thrust Manipulation: A Randomized Controlled Trial,” International Journal of Osteopathic Medicine, Vol. 35, March 2020, pp. 5-12
- Staff Writer (2019) “The Effect of Chiropractic Spinal Manipulation on Tonic Pain: Study Released” Australian Spinal Research Foundation, https://spinalresearch.com.au/the-effect-of-chiropractic-spinal-manipulation-on-tonic-pain-study-released/
- Langevin H, (2020), “Reconneting the Brain with the Rest of the Body in Musculoskeletal Pain Research,” Journal of Pain, https://doi.org/10.1016/j.jpain.2020.02.006
