If you’ve ever been to see a Physiotherapist, Remedial Massage Therapist, Myotherapist, Osteopath, Rolfer, Kinesiologist or any other kind of manual therapist any time since about 1950s, chances are that they have at some point in the treatment poked a sore spot on your body, referred to it as a “Trigger Point” and proceeded to massage, insert a needle, press and hold it hard (release by ischaemic pressure) all in a very well-meaning attempt to reduce the tightness in this little focal point of muscle spasm, and thus relieve your pain.
The problem with this is that no one has ever successfully proven they exist.
A Trigger Point is defined as a focal region of muscular spasm, within a taut band, that will reproduce pain when pressed. Assuming this description of the commonly found tender bumps in peoples bodies was correct, then it would be a simple matter to do an ultrasound scan and show the dense area of muscular spasm, or do a biopsy and find a region of increased metabolic activity, or use an EMG to detect increased electrical activity (all of which have been done), but no clear consensus has been found that concludes that this phenomenon is detectable at all.
So what gives? You can feel the knots! They hurt!
Absolutely. In fact, there is some very good evidence to support using trigger point therapies such as dry needling, ischaemic pressure etc to treat a range of disabling musculoskeletal conditions. The problem is that all of these studies start with a description of a trigger point, and just assume that they are a priori truth, which they are not. So if we have evidence that treating sore spots works, but trigger points haven’t been proven to exist, then what are we doing when we treat them with needle, thumb, spiky ball?????
At this stage there are only theories. These theories may be proven to be just as false as trigger point theory, but we need more research to really uncover the truth. In a paper by John Quinter, and Milton Cohen (Clin J Pain. 1994 Sep;10(3):243-51) they suggest an alternative hypothesis that these tender spots are actually inflamed peripheral nerves (read more discussion on the issue here and here). Inflammation causes nerves to have a lower threshold for stimulus, meaning it takes less to get them to fire. In a sensory nerve in the skin, this would mean that gentle pressure that is normally non-painful would potentially give arise to a pain experience as the nerves are more sensitive. The palpable lump could be a result of the swelling around the spot where the nerve enters into the skin through a tubule from the tissue beneath (causing a lump). Voila! Tender bumps. This explanation also gives an answer as to why these bumps can refer pain to other regions away from the site, as peripheral nerves have collateral branches that could also be affected by the electrical activity in the original sensory nerve. We just don’t know yet, but this seems plausible if it is not a trigger point in the muscle.
What does this mean for physio / massage/ myo etc? Not too much really. No one is doubting that we can reduce someone’s pain by treating their sore spot, but it does mean we have to stop telling patients that we’re doing it by pressing their magical buttons. A more plausible and evidence based answer is that by causing an increased noxious stimulus (danger message) we cause the brain to activate it’s own filtering system, called Descending Noxious Inhibitory Control (DNIC). We know the brain is a regulatory organ, having something like 200 times more nerves going down to the body, than entering in to the brain from it. Any information traveling upward will be evaluated by the brain, and if it decides that the information isn’t important for survival, it will filter it out (inhibit the nerve firing). When the therapist pokes your sore spot in a safe clinical setting, your brain decides that it’s not really in danger, inhibits the messages from that region, relaxes any protective muscular guarding, and suddenly the patient has less pain and better movement. As a final addition to the trigger point discussion, there are those (including the authors of the discussion piece above) who suggest that if trigger points don’t actually exist, then sticking needles into a patients body is undefendable, given that the proposed mechanism of therapeutic benefit doesn’t stand up. This argument suggests that if skilled dry needling is no more effective than non-specific needling (poking needles in anywhere) then since it carries risk of infection, bleed, and other more serious complications in certain locations, then it should not be used when other safer treatments might be as effective.
Well, so that’s one myth out the window, so what about Myofascial Release Techniques? Everyone knows they work, the therapist mashes a part of your body until you’re sweating and crying, which loosens the tight fascial capsule around the muscle, and then you’re looser and moving better. Right?
A few key pieces of research have caused us to discount this as evidence based treatment.
Study one (Bereznik D et al) investigated the friction of skin as it moves over fascia during manipulation techniques (like those used by Physio / Chiro / Osteo) and found that this tissue boundary was essentially frictionless (negligible friction). What this means is that when we try to put directional force through the skin to stretch the fascia, all we end up doing is pushing down on the fascia, not stretching it (because the skin slips over the top, preventing the translation from being applied). Once we feel resistance, that’s just as far as the skin can stretch.
Study two (Chaudhry et al 2008) used mathematical modelling to evaluate the forces required to deform the ITB and plantar fascia, and predicted that to even produce 1% compression and 1% deformation (stretch) of this fascia requires more force than humans can generally produce.
So here’s the problem, we can’t apply shear force to the fascia because the skin just slips over it, and even if we could stretch it we’re not strong enough to do this anyway (and that type of force would likely cause all sorts of soft tissue trauma to overlying tissues).
But myofascial release makes you feel looser, so how does that work?
Again, we look to the wonderful nervous system. It is, after all, what senses and controls the organism (you). By providing the nervous system with novel sensory input in a region that has protective, guarding muscular contraction, particularly in the safe, clinical environment of an Allied Health practice, we are giving the brain some strong messages that it is not in danger and therefore the brain then reduces it’s protective output and relaxes the muscles. It is actually the patient’s brain that releases the guarding muscle, not the therapist “doing a release”.
Isn’t the brain an amazing thing?
If you need your sore spots treated, or just enjoy a good massage because of the incredibly healing effects of good, skilled touch – book online here