It is possible to damage nerves with massage, but it’s rare, and rarely serious. Massage induced nerve trauma is not something we really need to worry about, but it’s a common concern anyway, driven by excessive “nerve fear” in our society.1 I get a lot of questions like this one:
One thing that helps sometimes when my neck pain gets excruciating is to really dig my fingers hard into a couple of muscle knots in the back of the neck (not right on the spine but off to each side, below the occipitals), or to use a Thera Cane to do the same thing. Is there any chance of causing nerve damage from so much pressure?
reader Peter Spaeth, Boston
In this article, I’ll discuss the physical protection most nerves have, some of the potentially more vulnerable locations (endangerment sites) around the body, the inherent resilience of nerves — they aren't fragile. Despite all that, there isn't zero risk, and extra caution needed with any kind of massage tool, with unusual intense massage, with stretch, and/or some specific areas. How about the notorious vagus nerve? I will explain why there’s no plausible risk of damaging the vagus, or “stimulating” it in a harmful way — although there is other nearby anatomy that is somewhat dangerously vulnerable.
I did cause a nerve injury once in ten years working as a professional massage therapist — so I will tell that embarrassing, cautionary tale.
EXCERPT This article is an adapted excerpt from my neck pain book. The same question is also addressed as a common question about strong massage in my trigger points book.
Why nerves are not very vulnerable to massage
It is nearly impossible to damage your nerves with moderate self-massage, because:
- Nerves are mostly padded well by other tissues.
- Healthy nerves are not fragile, and are no more likely to be damaged by moderate pressure than muscle tissue, blood vessels, or tendon.
- If threatened with trauma from pressure or tension, nerves produce plenty of warning sensations that will stop any sensible person before much harm is done.
There is a little more risk if you aren’t massaging yourself, or if you are doing so with a tool or method that makes it easier to accidentally apply too much pressure too quickly (before you sense the danger). But still not much much more danger.
Larger nerves are mostly protected
The larger nerves and nerve roots — the only nerves of real concern2 — are mostly well shielded by skin, fat, muscle, and bone. It’s particularly unlikely that you could harm yourself by massaging in the location Peter asked about, on the back of the neck (beside and behind the spine). The only prominent nerves in the back of the neck are the nerve roots, the bundles of nerve tissue that emerge from between each pair of vertebrae. But these are under a thick layer of sturdy paraspinal musculature, at least a centimetre or two.
Not all nerves are well-protected, of course…
Endangerment, Will Robinson!
There are a few places in the body where nerves are more exposed and can be injured by stronger pressures. All of these sites are familiar to any well-trained massage therapist, and known as “endangerment sites,” but the danger is minimal. Mostly they are just “unpleasantness sites.” These are not places most people want massage.
Here are all of the commonly cited endangerment sites (nerves highlighted):
|anatomic location (plain English)||potentially vulnerable anatomy|
|Anterior Triangle of the Neck (throat)||carotid artery, jugular vein, vagus nerve; under sternocleidomastoid|
|Posterior Triangle of the Neck (side of the throat)||nerves of the brachial plexus, proximal; brachiocephalic artery; subclavian artery & vein|
|Axillary Area||(armpit) brachial artery, axillary vein & artery, cephalic vein; nerves of brachial plexus, distal|
|Medial Epicondyle, Humerus (inside elbow)||ulnar nerve|
|Lateral Epicondyle, Humerus (outside elbow)||radial nerve|
|Umbilicus region (belly)||descending aorta & abdominal aorta|
|lateral 12th rib (lowest rib)||kidneys|
|Greater Sciatic Notch (buttocks, beside tailbone)||sciatic nerve|
|Inguinal Triangle (groin)||external iliac artery; femoral artery; great saphenous vein; femoral vein; femoral nerve|
|Popliteal Fossa (back of the knee)||popliteal artery & vein; tibial nerve|
|Hollow under the earlobe||parotid salivary gland, facial nerve|
The endangerment sites are debatable and in some cases definitely misleading. Nerves are everywhere, and there are many locations where they are potentially just as vulnerable to pressure as some of the ones listed above … but no one has ever proposed them as endangerment sites.3 The idea that the sciatic nerve is “exposed” to any degree in the sciatic notch, for instance, is a bit ridiculous (compared to the ulnar nerve, say, which certainly is exposed at the elbow).
And you can easily massage the scalene muscle group (in the posterior triangle of the neck) without ever bothering a nerve fibre. Extra caution is justified in this area, but not because the brachial plexus is notoriously sensitive — it’s more because of the carotid artery.
If you massage these locations with reasonable caution, you might feel electrical, zappy, funny-bone-esque pains… but you will very likely feel them before there is any actual danger. Healthy nerves aren’t particularly sensitive, but they will speak up if they are on the verge of being crushed or torn (like any tissue).
Nerves aren’t fragile
Very little healthy anatomy is “fragile.” If blood vessels were readily damaged by massage, you’d see that clearly: bruising and blood blisters would be common. But that almost never happens with massage at reasonable intensities. And it doesn't happen to nerves either. If you want to damage soft tissue, you'd almost have to make a point of it.
Which isn’t unheard of, actually.4 All the various kinds of no-pain-no-gain techniques are of dubious value and have real risks — even serious poisoning, and I wish I was exaggerating.5 For more information about the risks and benefit of intense massage, see The Pressure Question in Massage Therapy.
But at mild to moderate pressures in more or less healthy patients, there is virtually no risk to most nerves, most of the time.
Healthy nerves aren’t particularly sensitive to pressure … but unhealthy ones are
Most nerves, most of the time, can be firmly squeezed without producing any symptoms whatsoever. This is an experiment you can do yourself. The ulnar nerve — the “funny bone” — is tolerant of almost any fingertip pressure, and only produces that infamous zing with much greater force.
However, there are probably circumstances where nerves can be more sensitive — when they have been sensitized by pathology, or a slow-motion insult like chronic compression. In that situation, nerves can be much more easily irritated, either due to a relatively obvious mechanism like being oxygen starved,678910 subtle systemic inflammation, or more exotic factors like autoimmune disease, cardiovascular disease… which are in turn affected by diet, fitness, stress, sleep, genetics, and more!
In short, pressure sensitive nerves are probably a symptom. And that's probably not rare.
However, being sensitive to pressure isn't the same thing as being more vulnerable to damage. While more advanced pathology affecting the health of a nerve might plausibly make it more fragile, by that point you probably have some frank neuropathy.
Despite the fact that nerve-pinch pain is a thing, it’s clear that tissue health is probably the more important factor. The vulnerability of the nerve before it’s pinched is probably more important than the fact that it’s being pinched, or how hard. And how vulnerable the nerves are may be affected by factors that have nothing whatsoever to do with your back.
Nerves and stretch
Nerves are probably more vulnerable and sensitive to stretch than pressure — especially if they they are “snagged” in their sheaths, a predicament known as a tunnel syndromes.11 This might be common. Or not. It’s not entirely clear how real a problem tunnel syndromes are, but certainly there’s something to it. There are some obvious tunnel syndromes. But is it the tip of an iceberg of less obvious ones? No one knows!
The problem is not well understood, and neither is the treatment. But neurodynamic stretching is intended to actually free nerves from their snags … or perhaps just stimulate the neural tissue enough to make it a little happier.
What is certain is that nerves can be injured by excessive stretch, and in fact it’s probably a more common way for them to get hurt than direct pressure. And — fascinatingly — there might be a grey zone between "stretch injury" and "tearing nerves free of their snags." This is all unknown to science. And the rabbit hole goes even deeper…
Micro tunnel syndromes as the mechanism of “trigger points”
Another intriguing possibility is that the sensitivity of nerves and the sore spots commonly known as “trigger points” are actually the same thing. That is, trigger points might be the sensitivity of vulnerable nerves. This is in contrast to the much more widely believed “tiny cramp” model of a trigger point.12 This idea is highly speculative; I’m including it just because it’s quite an interesting notion in this context.
If so, then pressing on them isn’t likely to injure them, or even cause clasically zappy nerve pain: just the familiar aching and burning of common muscle pain. The nerves are clearly vulnerable in some sense, but probably not to injury.
Can neck massage stimulate the vagus nerve? For worse or better?
Nope. The vagus nerve is the least of your worries — or opportunities — for massage on the side of the neck and throat. This members-only section explains some genuine dangers, and the much less realistic concern about why people worry about vagus nerve stimulation in the first place. I talk about the carotid sinus reflex and why it’s considered a “vagal manoeuvre” and potentially risky, and yet not actually an example of vagus nerve stimulation.
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The vagus nerve is a ginormous nerve, almost entirely dedicated to the management of things like blood pressure and respiration. The vagus emerges from the bottom of your brain and passes through the neck and into the trunk, branching out from there to connect to … almost everything (most organs). There is a lot of hype about the vagus nerve and its role in our health.
True vagal neuropathy exists, and it’s no joke.1314151617 But the medical literature is notably lacking in case studies of injury to the vagus nerve (other than the ones caused by surgery!). This is not an easy nerve to injure without a scalpel, and you’re not likely to do it with massage unless you get quite vicious with pressure in an area where that is obviously a Bad Idea. Any massage intense enough to even annoy the vagus nerve would also be risking other kinds of injury, some of them worse:
- ⚠️ Damaging other more delicate nerves (like the brachial plexus).
- ⚠️ Tearing the carotid artery, cause or dislodge a clot or some plaque.
- ⚠️ Triggering the carotid sinus reflex strongly, which is mostly harmless but could cause an uncomfortable drop in blood pressure in some people, or even fainting in a few.
So the vagus nerve is really the least of your worries in this area.
An example of vagus neuropathy due to overgrowth of the weird styloid process (highlighted), which causes mostly neck & throat pain, but can also get weirder. Case courtesy of Dr. Ammar Haouimi, Radiopaedia.org case rID: 81953.
The carotid sinus reflex: vagal or not?
Carotid sinus massage and carotid sinus hypersensitivity trigger the carotid sinus reflex, which is a blood-pressure lowering reflex. Baroreceptors (pressure detectors) are clustered in the carotid sinus, a bulge in the artery where it forks, beside the Adam’s apple. This pesky reflex is probably a major reason why some people are concerned about vagal stimulation from neck massage… and all the more so because it seems to have a hair trigger in some people. Carotid sinus hypersensitivity is actually common, but mostly so mild that people don’t even know they have it, so it is probably rare for it to cause dizzying blood pressure drops or fainting. But it is a thing, and people might be well aware of a tendency to feel weird or gross when this area is rubbed or stretched.
A few people who have this self-awareness probably attribute it to “vagus nerve stimulation” — because the carotid sinus reflex is widely seen as vagal thing. Except… it’s not a vagal thing. Some readers might be quick to try to contradict me on this. “But Paul!” they will say, “Carotid sinus massage is a ‘vagal manoeuvre.’ So it’s obviously vagal stimulation!”
This is a great example of the devil being in the (interesting) details. It’s not vagal in two ways:
- It triggers a reflex… which is not really what people mean by “stimulates the vagus nerve.”19
- That reflex is not mediated by the vagus nerve! Surprise!20
On the other hand, this is indeed considered one of the “vagal manoeuvres,” because it is so similar in “spirit” to other reflexes that are mediated by the vagus nerve … but cannot be triggered by massage! I don’t recommend trying to stimulate the aortic arch baroreceptors with your bare hands. That would get ugly.21 😜
With great power comes great responsibility, and so some people who believe in the power of vagal stimulation are also afraid of the “power” of vagus stimulation. This is unnecessary, because there is no such power to abuse. You just cannot “stimulate the vagus nerve” dangerously or significantly with any ordinary massage any more than you can “stimulate” the ulnar nerve to do what the ulnar nerve does, or the sciatic nerve, or any nerve. It’s like trying to turn on a light by massaging the cord (hat tip to Mark O. for that analogy).
Therapeutic vagus stimulation with electricity is a real thing, albeit only half-baked. But there is no other known way to meaningfully stimulate the vagus nerve — for good or ill — and certainly not with any neck massage that you’d want to receive (or deliver).
There are good reasons to avoid massage of the side of the throat and neck, or to do it only slowly and gently and cautiously. But vagus stimulation is not the reason why.
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What happens if you push your luck and push too hard on nerves?
Push hard enough, and you can injure a nerve, of course. In a 2017 incident, a woman’s radial nerve was crushed by an aggressive massage in her upper, inner arm. It’s rare, but it happens.22 Deliberately ramping up pressure on a sensitive nerve is hard to do, like sticking your hand into a jar of scorpions. And yet, surprisingly, sometimes people still do it! It’s amazing what we can put up with if we think it’s necessary, and the no-pain-no-gain attitude inspires a lot of foolishness.
Nerves can recover from a lot of abuse, up to and including being mangled in nasty accidents, or being pinched hard for years. For instance, many people who have severe carpal tunnel syndrome — years of disabling median nerve impingement — often recover just fine once pressure on the nerve is finally relieved by surgery.
In the unlikely event that you cause yourself a nerve injury, it would probably only result in annoying but trivial symptoms that would take a few days to resolve, or perhaps a few weeks at the worst. But I have rarely heard of this happening by self-massage — it’s just too unpleasant as you approach the point of injury to actually get there.
Please beware of tools
I’m sure that there are people, somewhere out there, who have hurt their nerves with self-massage. And I bet most of them were using a massage tool. When you use massage tools, it may be easier to apply too much pressure too quickly … before you have that “I’ve made a huge mistake” moment.
It’s harder to control tools, and hard to tell what’s going on when you’re sensitive fingers and thumbs aren’t involved. For example: you can easily feel the pulse of an artery when you are massaging with your fingers, but you can’t feel it at all when you use a tool.
So if you use a tool, use it with extra caution.
A nice, simple massage tool … but not recommended for use in vulnerable areas like the sides & front of the throat!
That one time I injured a client’s nerves
Once upon a time I pushed my luck, and injured a patient’s cervical plexus — this area where most people will probably never self-massage strongly. I injured him by applying strong pressures in a vulnerable area too quickly. It was one of my more reckless moments in a decade of mostly quite gentle massage.
He was alarmed and unhappy with me, of course, but his symptoms were minor: he had annoying flashes of moderate pain that slowly faded over about three weeks, and probably the worst thing about it was simply that he was less sure of his prognosis than I was. I knew he’d get better steadily, but he didn’t know if he could trust my opinion! Fair enough.
About Paul Ingraham
I am a science writer in Vancouver, Canada. I was a Registered Massage Therapist for a decade and the assistant editor of ScienceBasedMedicine.org for several years. I’ve had many injuries as a runner and ultimate player, and I’ve been a chronic pain patient myself since 2015. Full bio. See you on Facebook or Twitter., or subscribe:
- The Pressure Question in Massage Therapy — What’s the right amount of pressure to apply to muscles in massage therapy and self-massage?
- The 3 Basic Types of Pain — Nociceptive, neuropathic, and “other” (and then some more)
- Nerve Pain Is Overdiagnosed — Our cultural fear of neuropathy, and a story about nerve pain that wasn’t
- Basic Self-Massage Tips for Myofascial Trigger Points — Learn how to massage your own trigger points (muscle knots)
- Massage Therapy Side Effects — What could possibly go wrong with massage? The risks and side effects of massage therapy are usually mild, but “deep tissue” massage can cause trouble
- “Can Massage Cause Muscle and Nerve Damage?” by Ravensara Travillian explores two potential consequences of intense massage, both rhabdomyolysis and peripheral neuropathy.
What’s new in this article?
Aug 18, 2022 — Added a new section: “Can neck massage stimulate the vagus nerve, for better or worse?”
2017 — Added much more information about endangerment sites, discussion of the potential relevance of neuritis, extensive clarifications and editing, and some footnotes.
2008 — Publication.
- Nerves make people nervous! So to speak. The whole idea of nerves gets people anxious. Could it be a nerve? people ask. Is this a nerve problem? What if it’s a nerve? Is something pinching my nerve? Something must be pinching a nerve.
- Most smaller nerves, even when seriously damaged, are unlikely to cause significant pain, suffering, or disability.
- A good example is the mandibular notch, which is just under the cheekbone and in front of the jaw joint. It’s full of nerves, but completely safe to massage — indeed, it’s a particularly nice spot to massage. See Massage Therapy for Bruxism, Jaw Clenching, and TMJ Syndrome.
The goal of provocation therapy is to “break some eggs to make an omelette,” to kickstart tissue healing by damaging it. The most obvious examples are various kinds of “scraping” massage. Some tools and products, like the notorious Fascia Blaster, also cause bruising (as commonly abuse, which seems inevitable the way that product is marketed).
Although the most obvious effect is bruising from a lot of broken blood vessels, nerves undoubtedly get hurt sometimes as well.
Deep tissue massage sometimes has the same goal (usually unstated), or some soft tissue damage is just accepted as minor collateral damage in pursuit of some other therapeutic goal (such as trying to remove fascial “distortions”, and fascia is much tougher stuff than muscle, vessel, or nerve).
- Sometimes we feel cruddy after a massage, like it was a big workout. Post-massage soreness and malaise (PMSM) is embraced as a minor side effect and hand-waved away by almost everyone as some kind of no-pain-no-gain thing. But it needs explaining. Massage is not “detoxifying” in any way (that’s pseudoscientific nonsense). Ironically, it may be the opposite: some PMSM is probably caused by mild rhabdomyolysis, a type of poisoning that can occur even with heavy exercise (a medical reality), and possibly strong massage (a plausible hypothesis). If so, it’s a big deal, a serious side effect. There are also some non-rhabdo explanations for milder PMSM. See Poisoned by Massage: Rather than being DE-toxifying, deep tissue massage may actually cause a toxic situation.
- Wilson CB. Significance of the small lumbar spinal canal: cauda equina compression syndromes due to spondylosis 3: Intermittent claudication. J Neurosurg. 1969;31:499–506. PubMed #5351760 ❐
An old topic review that explains that the belief that the pain may be caused by impairment of circulation to the capillaries of the spinal nerve roots.
- Mackinnon SE. Pathophysiology of nerve compression. Hand Clin. 2002 May;18(2):231–41. PubMed #1237102 ❐
From the abstract: “Both ischemic and mechanical factors are involved in the development of compression neuropathy.” In other words, mechanical factors only — just being pinched — probably does not cause nerve pain.
- Kobayashi S, Shizu N, Suzuki Y. Changes in nerve root motion and intraradicular blood flow during an intraoperative straight-leg-raising test. Spine. 2003 Jul 1;28(13):1427–34. PubMed #12838102 ❐
Kobay et al. surgically examined blood flow to a lumbar nerve root while the leg was in a painful position. (They peeked into twelve backs with a history of symptomatic disk herniations and nerve pain.) They found that “the intraoperative reverse straight leg raise test showed that the hernia compressed the nerve roots, and that there was marked disturbance of gliding, which was reduced to only a few millimeters,” and “during the test, intraradicular blood flow showed a sharp decrease [40 to 98%] at the angle that produced sciatica.”
Intriguing. It’s probably the physical distortion of the nerve root that caused the loss of circulation, and the combination of the two that was painful. Successful treatment seemed to back this up: “After removal of the hernia, all the patients showed smooth gliding of the nerve roots during the second intraoperative test, and there was no marked decrease in intraradicular blood flow.”
- Jayson MI. The role of vascular damage and fibrosis in the pathogenesis of nerve root damage. Clin Orthop Relat Res. 1992 Jun;(279):40–8. PubMed #1534723 ❐ It “appears likely that venous obstruction with resultant hypoxia is an important mechanism leading to nerve root damage.” And why would blood supply to a nerve root be impinged? According to Jayson, “Vascular damage and fibrosis are common within the vertebral canal and intervertebral foramen.” Especially after surgery! But not only after surgery. The delicate capillaries around nerve roots seem to degenerate just like joints get arthritic, and that process is probably accelerated by biological factors like autoimmune disease, cardiovascular disease, and chronic low grade inflammation … which are in turn affected by diet, fitness, stress, sleep, etc.
- Sore spots in muscles are measurably hypoxic. See Toxic Muscle Knots
- Sometimes, due to pathological processes and physical predicaments, nerves get pressed against and stuck to the walls of their tubes, like microscopic velcro. This predicament is usually called “neural tension” or a “tunnel syndrome.” You don’t want this happening to your nerves any more than your cat wants tape on its paws. It affects their function. The membrane of the nerve itself is no longer floating freely, so ions can no longer rush in and out of that section of membrane quite so well. The result: pain, numbness, tingling. Neuropathy.
- Quintner JL, Bove GM, Cohen ML. A critical evaluation of the trigger point phenomenon. Rheumatology (Oxford). 2015 Mar;54(3):392–9. PubMed #25477053 ❐
This infamous paper firmly concludes that the integrated hypothesis of trigger point formation is “flawed both in reasoning and in science,” and they propose some replacements, including inflamed nerves — small nerves chronically slightly irritated by minor tunnel syndromes.
For more about the controversy over the nature of trigger points, see Trigger Points on Trial.
- Badhey A, Jategaonkar A, Anglin Kovacs AJ, et al. Eagle syndrome: A comprehensive review. Clin Neurol Neurosurg. 2017 Aug;159:34–38. PubMed #28527976 ❐
- Klein TA, Ridley MB. An old flame reignites: vagal neuropathy secondary to neurosyphilis. J Voice. 2014 Mar;28(2):255–7. PubMed #24315656 ❐
- Rees CJ, Henderson AH, Belafsky PC. Postviral vagal neuropathy. Ann Otol Rhinol Laryngol. 2009 Apr;118(4):247–52. PubMed #19462843 ❐
- An Y, Park K, Lee S. The First Case Report of Bilateral Vagal Neuropathy Presenting With Dysphonia Following COVID-19 Infection. Ear Nose Throat J. 2022 Feb:1455613221075222. PubMed #35164601 ❐ PainSci #51343 ❐
- Tan ET, Johnson RH, Lambie DG, Whiteside EA. Alcoholic vagal neuropathy: recovery following prolonged abstinence. J Neurol Neurosurg Psychiatry. 1984 Dec;47(12):1335–7. PubMed #6512554 ❐ PainSci #51339 ❐
- Lacerda Gd, Lorenzo AR, Tura BR, et al. Long-Term Mortality in Cardioinhibitory Carotid Sinus Hypersensitivity Patient Cohort. Arq Bras Cardiol. 2020 02;114(2):245–253. PubMed #32215492 ❐ PainSci #51342 ❐
- A reflex arc is precise: it does only one thing, and it’s pathway is just one “lane” of the huge multi-lane highways of nerves. The vagus nerve is particularly large, and mediates several reflexes and much else. When people talk about “vagal stimulation,” they are not talking about triggering a single reflex: they are (very optimistically) talking about stimulating all of its functions … which would induce deep relaxation. Triggering your baroreflex doesn’t do that. Does getting a trumpet to toot a few notes count as “stimulating” an orchestra?
The carotid baroreceptors come from the glossopharyngeal nerve, and their effect on the brain is actually kind of the reverse of “vagus stimulation.” The baroreflex works by decreasing the activity of the sympathetic division of the autonomic nervous system… but the vagus is the main arm of the parasympathetic. Low blood pressure does the reverse: rather than boosting blood pressure by “disinhibiting” the sympathetic.
It’s all fiendishly complex, and I am not going to definitively say that the vagus nerve isn’t involved at all in the carotid sinus baroreflex. For instance, there is evidence that the vagus nerve does contain sympathetic fibres — but mostly it’s all about parasympathetic function, while the baroreflex is mostly a sympathetic weirdo.
Like I said above, the devil is in the details… and there are a lot of details here.
- The baroreflex has two batches of pressure sensitive nerve endings, one in the aortic arch in the chest, and the other in the carotid artery in the neck. But the baroreceptors in the carotid sinus are wired to the CNS via the glossopharyngeal nerve, but the aortic arch baroreceptor axons travel within the vagus nerve. After that point, we’re back to a mainly sympathetically mediated reflex, not a parasympathetic (vagus) one — despite the vagus involvement in the sensory half of the arc.
- Hsu PC, Chiu JW, Chou CL, Wang JC. Acute Radial Neuropathy at the Spiral Groove Following Massage: A Case Presentation. PM R. 2017 Apr. PubMed #28400223 ❐