People think of massage therapy as a “safe” therapy, and of course it mostly is. But things can go wrong, or at least a bit sour. While serious side effects in massage therapy are extremely rare, minor side effects are fairly common. A 2007 survey of 100 massage patients1 found that 10% of 100 patients receiving massage therapy reported “some minor discomfort” in the day following treatment. This would mainly be a familiar slight soreness that is common after a massage, known as “post-massage soreness and malaise” (PMSM) — and I’m surprised only 10% reported it. The massage must have been quite gentle.2
Interestingly, 23% reported unexpected benefits that had nothing to do with aches or pains.
(Also interesting is that this means that most of these patients experienced no noteworthy effect at all, good or bad! Hopefully they enjoyed the massage at the time …)
This study is underpowered (small) and cannot and does not rule out rare and/or serious side effects of massage therapy, which certainly do exist. You could probably do several studies of 100 patients without encountering a single nasty situation. But what if you surveyed 1000 patients? Or 10,0000? Massage is not completely safe — what is? — and some other adverse effects would almost certainly turn up in a large enough survey. Nevertheless, according to one of alternative medicine’s most vigorous critics, Dr. Edzard Ernst, “Serious adverse events are probably true rarities.”3
In my decade as a massage therapist, I met many patients who had been harmed by massage therapy to some degree: several dozen of them who experienced nothing but minor negative effects and a light wallet, expensive disappointments; and perhaps a dozen whose chronic pain problems were worsened; and a handful more who were quite clearly injured by massage.
A painful, alarming sensory experience can actually dial up pain sensitivity — even long term.4 Furthermore, vulnerability to this awful phenomenon is much more common and significant in desperate patients who already have chronic pain — so they seek and tolerate intense therapy.
The experience of pain is affected by many factors, including emotional and psychological ones. People in chronic pain usually experience some degree of pain neurology dysfunction, and a breakdown of the relationship between how bad things feel and how much is really wrong. That breakdown can be seriously worsened by threatening sensations. Thus, people experiencing pain system dysfunction can have minor and major setbacks in response to excessively painful massage.
One of my readers suffered this kind of disaster. She was injured by “fascial release” therapy, a style which is often too intense and may focus on treating connective tissues to the exclusion of considering the patient’s comfort and nervous system.
I may have been too aggressive with a few patients over the years. I never did serious harm this way as far as I know, but I’m sure that I occasionally did more harm than good. This failure was due entirely to ignorance of pain science. I simply did not know that an intense massage could change pain sensitivity itself. Does your therapist?
Excessive pressure probably has another predictable outcome: a light poisoning.
An 88-year old man collapsed the day after an unusually strong 2-hour session of massage therapy.5 He had too much myoglobin in his blood, and it was poisoning his kidneys and generally making him feel rotten. It’s not a sure thing that his condition was cause by the massage — but it is quite likely. It is almost certainly a perfect example of one of those rare but serious complications of massage. Another case study comes up below.
Ironically, many people believe that massage is a detoxification treatment, but in fact it’s probably the opposite. Ironically, many people believe that massage is a detoxification treatment, but in fact it’s probably the opposite. Post-massage soreness and malaise is probably caused by mild rhabdomyolysis (“rhabdo”): poisoning by the waste products of injured muscle
True rhabdo is a medical emergency in which the kidneys are poisoned by myoglobin from muscle crush injuries. But many physical and metabolic stresses cause milder rhabdo-like states — even just intense exercise, and probably massage as well. There are many well-documented cases of exertional or “white collar” rhabdo, and there is a strong similarity between PMSM and ordinary exercise soreness. A rhabdo cocktail of waste metabolites and by-products of tissue damage is probably why we feel a bit cruddy after all biological stresses and traumas — including massage, sometimes.
PMSM is just an unavoidable mild side effect of strong massage. And for a few more vulnerable patients, it could actually be a little dangerous.
The neck is not generally a fragile structure, but it is in some people. Another serious example of an adverse effect of massage is what happened to my barber — either a brain stem injury or mini-stroke caused by careless massage of a vulnerable neck. One of my own patients was injured the same way by another therapist, vomiting and retching for hours afterwards (a nasty symptom of brain stem impingement, or ripping of an artery going to the brain). I came close to doing this to another patient — that’s three examples of such patients in my career — but I’m proud to say that I spotted the warning signs and avoided disaster.
A weird case of brain artery damage (extracranial internal cartoid artery dissection, specifically) was reported in 2004 by the Southern Medical Journal: a 38-year-old woman gave herself a stroke by using a vibrating massage tool for long and too hard on her neck.6 Obviously such an incident has little to do with professional massage. Nevertheless, it demonstrates that the arteries of the neck are a little bit fragile — and I have no doubt that there are poorly trained or incompetent therapists out there would might get carelessly exuberant in this region, while trying to treat the scalenes: see Massage Therapy for Neck Pain, Chest Pain, Arm Pain, and Upper Back Pain.
Another weird, extreme case study paper tells the horror story of one person’s awful experience with a severe reaction to (apparently) infrared heat and massage therapy.7 The trouble started after several treatments. His neck and arms were swollen, the pain became “unbearable,” and his “serum muscle enzymes were increased” — which means some degree of rhabdo, which implicates the massage itself as a significant mechanism of injury. Massage is not likely to “blame” for the incident, though — it was probably interacting with some unidentified vulnerability in the patient, such a muscle disease or a complication caused by a medication. Clearly massage and heat alone do not normally cause such severe side effects! Nevertheless, the potential for very unpleasant interactions exists.
“Alternative therapies may have serious complications, and patients usually do not report them unless asked specifically,” the authors point out.
I am one-degree of separation from a patient whose femur (the big leg bone!) was fractured by a massage — it was a weak and injured femur already … but wow!
Nerves aren’t nearly as vulnerable to pressure as people generally think — most of them can actually take quite a licking and keep on ticking without a single symptom — but they aren’t invulnerable. And I once caused a nerve injury myself: it was a minor injury, but it did — augh — result in weeks of aggravating discomfort for my client. The Archives of Physical Medicine & Rehabilitation reported a similar spinal accesory nerve injury: “a rare and illustrative case of spinal accesory neuropathy associated with deep tissue massage leading to scapular winging [the shoulder blade sticking out] and droopy shoulder as a result of weakness of the trapezius muscle.”8
These are rare but real incidents. Healthy people are unlikely to be injured by massage. Most of dangers are related to undetected vulnerabilities, and they emphasize the importance of alternative health professionals being trained to spot the scary stuff. The measure of a health professional’s competence is not what they do with relatively healthy patients, but whether they have the training and humility to realize when they are on thin ice.
Manual therapists need to know that the most important part of their job is the smart management high-risk situations that they may see only a handful of times in their entire career. It’s like being on guard duty: 99.9% of the time, nothing bad happens. But how do you handle a curve ball when it finally comes?
Consumers need to know that cocky, overconfident therapists who trash-talk “mainstream” health care are all-too-likely to be ignorant of critical warning signs, or dismissive of them. The skeptical salamander thinks these therapists shouldn’t be allowed to touch anyone. See Missing Serious Symptoms.
I am a science writer, former massage therapist, and assistant editor of Science-Based Medicine. I have had my share of injuries and pain challenges as a runner and ultimate player. My wife and I live in downtown Vancouver, Canada. See my full bio and qualifications, or my blog, Writerly. You might run into me on Facebook and Google, but mostly Twitter.
Is massage safe? Researchers attempted to answer that question. Four databases were reviewed; all articles which reported adverse effects of any type of massage therapy were looked at. In the end, 20 reports were looked at. “The majority of adverse effects were associated with exotic types of manual massage or massage delivered by laymen, while massage therapists were rarely implicated.”
The conclusion was that, while not entirely risk free, “serious adverse events are probably true rarities.”BACK TO TEXT
Pain itself often modifies the way the central nervous system works, so that a patient actually becomes more sensitive and gets more pain with less provocation. That sensitization is called “central sensitization” because it involves changes in the central nervous system (CNS) in particular — the brain and the spinal cord. Victims are not only more sensitive to things that should hurt, but also to ordinary touch and pressure as well. Their pain also “echoes,” fading more slowly than in other people.BACK TO TEXT