Written by Dr Katie Stephens, GP
Dr Katie graduated from the University of Manchester in 2007 (MBChB) and completed her GP training in the West Midlands in 2012 (MRCGP).
What is MS (Multiple Sclerosis)?
This is a medical condition where the insulating fat around a nerve (myelin) gets attacked by the body’s own immune system. As the fat is necessary for the nerve to work efficiently, this typically results in either the nerve not working properly or potentially not even working at all.
As nerves are responsible for a whole host of different functions in our bodies, the symptoms of MS will look different from one person to another, depending on which of their nerves are affected. For instance, if the nerve is involved in passing on information regarding touch sensitivity in part of your left hand, you may notice reduced sensation, tingling, pain or numbness there. If it is involved in telling your right calf muscle to contract, you may notice a weakness, cramping, or tightness in the muscle, which might cause difficulty coordinating movements even while just walking. There are other more generalised symptoms of MS as well, such as fatigue and poor concentration.
While there are different sub-types of MS, and certain symptoms are more common than others, there is usually a general trend of the condition worsening over time. Fortunately, there are treatment options available that can both help with flares of symptoms as well as potentially reduce the rate of overall disease progression1.
What is TENS?
TENS stands for Transcutaneous (meaning ‘through the skin’) Electrical Nerve Stimulation – quite a mouthful! TENS machines are small electrical devices with pads that stick on to your skin. They are commonly used to treat pain stemming from a variety of causes, such as period pains, arthritis and musculoskeletal injuries.
How does TENS work?
The sticky pads that attach to your skin are electrodes. When the machine is turned on, pulses of electrical current are delivered via these pads. It is thought that this electrical signalling can interfere with the way the local nerves are communicating pain to the brain, effectively reducing the feeling of pain and promoting relaxation of local muscles. They may also stimulate endorphin production, which can have a further impact on pain reduction2,3.
Can TENS reduce pain for MS (multiple sclerosis) patients?
According to a meta-analysis of evidence up until 2014, there is GRADE 2 evidence that using TENS is a safe and effective method of managing central pain in people with MS4 (‘central pain’ here referring to pain coming from the nerves damaged by MS). There are lots of different ways of rating evidence quality so it is worth giving a brief explanation of what this means – the definition of ‘GRADE 2’ evidence is that ‘further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate’5. In other words, there is evidence of an effect and the quality of that evidence is reasonably good (GRADE 1 is high quality, 2 is moderate, 3 is low and 4 is very low).
A more recent meta-analysis of a wider pool of data including using TENS for pain coming from different sources, not just MS, was published October 2021. This found multiple examples of evidence which had sufficient data for TENS being effective at reducing pain, and zero meta-analyses with sufficient evidence showing no benefit6.
Without getting too bogged down in the technical details, the overall take home message here is that there appears to be fairly good (if not perfect) evidence that TENS machines can help reduce pain, including in people with MS. This is still an area that is being studied currently and there may be more findings appearing in journals in the near future.
What are the benefits of using TENS for MS (multiple sclerosis) patients?
The benefits of using TENS for people with MS aren’t just limited to pain reduction, but may also be seen in the following areas:
Can TENS reduce spasms for MS (multiple sclerosis) patients?
One small study from 2007 involving 32 subjects found that TENS machines appeared to be helpful with reducing muscle spasms in people with MS when used for long periods of time7 (the study had users spend either 60 minutes or 8 hours/day using the machine). It didn’t show a benefit with reduced spasticity, however. To clarify, a muscle spasm refers to a sudden involuntary muscle jerk which can be painful and disruptive while spasticity means a background stiffness in a muscle which may make it hard to move. Both are potential symptoms that people with MS may suffer from.
A more recent, larger, review of about 2700 patients was published in 2018 and suggested that actually TENS could be considered as a treatment for spasticity in MS, with botox injections being the best intervention8.
Improved tactile sensitivity
As mentioned earlier, one possible symptom of MS is reduced sensation or numbness in one part of the body – a bit like how your face feels after getting a local anaesthetic injection at the dentist. One paper assessed the effect of using a TENS machine for an hour each day for 3 weeks. The researchers measured the skin sensitivity before treatment, 12 hours after the last treatment, and 3 weeks after this.
It found that the sensitivity in patients who had MS had improved to the level of the healthy subjects at the end of the treatment period. Interestingly, this improvement was not only confined to the nerve treated but also seen in another nerve nearby, and there was still an improvement noticed when tested again 3 weeks later9.
If you’d like more information about MS, including getting access to support for you or a loved one, please visit the MS Society10, MS-UK11 or the Multiple Sclerosis Trust12. Kinetik’s TENS machines can be found here13.
- Vance, C. G., Dailey, D. L., Rakel, B. A., & Sluka, K. A. (2014). Using TENS for pain control: the state of the evidence. Pain management, 4(3), 197–209. https://doi.org/10.2217/pmt.14.13
- Sawant A, Dadurka K, Overend T, Kremenchutzky M. Systematic review of efficacy of TENS for management of central pain in people with multiple sclerosis. Mult Scler Relat Disord. 2015 May;4(3):219-27. https://doi.org/10.1016/j.msard.2015.03.006 Epub 2015 Apr 8. PMID: 26008938.
- Guyatt G H, Oxman A D, Vist G E, Kunz R, Falck-Ytter Y, Alonso-Coello P et al. GRADE: an emerging consensus on rating quality of evidence and strength of recommendations BMJ 2008; 336 :924 https://doi.org/10.1136/bmj.39489.470347.AD
- Paley, C. A., Wittkopf, P. G., Jones, G., & Johnson, M. I. (2021). Does TENS Reduce the Intensity of Acute and Chronic Pain? A Comprehensive Appraisal of the Characteristics and Outcomes of 169 Reviews and 49 Meta-Analyses. Medicina (Kaunas, Lithuania), 57(10), 1060. https://doi.org/10.3390/medicina57101060
- Miller L, Mattison P, Paul L, Wood L. The effects of transcutaneous electrical nerve stimulation (TENS) on spasticity in multiple sclerosis. Mult Scler. 2007 May;13(4):527-33. https://doi.org/10.1177/1352458506071509 . Epub 2007 Jan 29. PMID: 17463075.
- Fu X, Wang Y, Wang C, Wu H, Li J, Li M, Ma Q, Yang W. A mixed treatment comparison on efficacy and safety of treatments for spasticity caused by multiple sclerosis: a systematic review and network meta-analysis. Clin Rehabil. 2018 Jun;32(6):713-721. https://doi.org10.1177/0269215517745348 . Epub 2018 Mar 27. PMID: 29582713.
- Cuypers K, Levin O, Thijs H, Swinnen SP, Meesen RL. Long-term TENS treatment improves tactile sensitivity in MS patients. Neurorehabil Neural Repair. 2010 Jun;24(5):420-7. https://doi.org10.1177/1545968309356301 . Epub 2010 Jan 6. PMID: 20053949.