The answer to this question will include current, state-of-the-art research, as well as my and my colleagues’ clinical experience over several decades. I will address each of the three questions in sequence.
1) What is the science behind trigger point deep muscle massage?
There are several theories for the etiology/pathophysiology of trigger points and myofascial pain syndrome. Research continues on each, as none have yet been decisively proven. Massage therapy (MT) has been studied extensively, and has been shown to produce objective effects most notably in those bodily systems which interact locally with the myofascial (muscle and connective tissue) systems. These include the local circulatory systems, local and central nervous systems, and the lymphatic system within the immediate vicinity of the area worked on. It should be noted that the fascial structures, which encapsulate the contractile structures and tissues, exert mechanical forces upon the other associated structures, thus affecting their physiological function. MT (specifically ischemic compression and friction massage) has been shown to be effective in releasing myofascial trigger points. MT also has minimal side effects, no drug interactions, is low cost, and often includes positive patient-practitioner relations (which lead to a positive and productive mentality during therapeutic treatment and rehabilitation).
2) It does work. But how?
MT that successfully releases trigger points includes ischemic compression and friction massage. Ischemic compression involves holding pressure steadily on a trigger point until it softens/releases. Friction massage involves sliding the finger/hand/etc. along a (usually) venous direction of a muscle. This creates a vacuum/suction effect upon the circulation which quickly introduces freshened circulatory fluids to the area, and moves inflammatory chemicals present back into general circulation. The freshened circulatory fluids include blood and lymph, which carry pain-relieving endorphins, as well as energy constituents for metabolic recovery for both the myofascial tissue and the neuromuscular junctions. Inflammatory chemicals removed include substance P, prostaglandins, bradykinin, etc.
If you’d like to see some of this for yourself, try this: locate the blue (venous) lines on the underside of your wrist. Press, then rub, slowly along the blue line toward the elbow. The blue line will go clear for a moment, then the blue, or venous, blood will return in a second or two. You have just performed friction massage to the veins which will drain blood and lymph from the tissues it serves. These tissues may contain nociceptive (pain inducing) and/or inflammatory biochemicals. If you flush the tissue of venous blood/lymph, creating a “quick-refresh” of arterial blood, the tissue will be flushed of painful biochemicals, while receiving pain-relieving biochemicals. This is the function of ischemic compression and friction massage for painful areas, including tissue with active trigger points.
3) How many sessions does it take before you feel relief?
If you have been properly diagnosed with MPS, and your practitioner is well-trained and experienced, you should feel immediate relief. Ischemic compression and/or friction massage releases a trigger point (and the attendant pain and tension) within a minute or two. If trigger points are extremely active, it may take several passes over an area to treat it completely.
There is a clinical understanding in our profession: the complex part of therapy is not releasing the patient’s pain (if you know what you are doing), but rather keeping them out of pain.
If your therapist is good, you will feel better, at least significantly, for a while. The task for you then is to:
- learn to do effective self-care to release the trigger points,
- stretch/strengthen the tissue, and
- track when the pain recurs, so that your practitioner can superimpose the timeline of recurrence with functional tasks, to possibly trace those tasks that need to be modified or eliminated (which will remove the trigger point’s perpetuating factor).
When these have been accomplished, you should be solidly on the road to recovery. Progress often follows a “two steps forward, one step back” pattern, as perpetuating factors are gradually eliminated and the tissue rehabilitates successfully. How long that will take depends on many factors: your age, general health, metabolic factors, stress levels, fitness, ergonomic factors, daily functional tasks, diet, sleep, emotional state, etc. Your doctor and therapist should help you to minimize the impact of triggers, and also to bolster those areas of overall healthy living that need help. If symptoms don’t improve noticeably within several weeks, you should seek other opinions and help.
 “Uncovering the biochemical milieu of myofascial trigger points using in vivo microdialysis: an application of muscle pain concepts to myofascial pain syndrome,” article on the Science Direct website.
 “Physiological and clinical changes after therapeutic massage of the neck and shoulders,” Article on the Science Direct website.
 “The Effects of Pressure Release, Phonophoresis of Hydrocortisone, and Ultrasound on Upper Trapezius Latent Myofascial Trigger Point,” article on the Science Direct website.
 “The muscular force transmission system: Role of the intramuscular connective tissue,” article on the Science Direct website.
 “Changes in Blood Flow and Cellular Metabolism at a Myofascial Trigger Point With Trigger Point Release (Ischemic Compression): A Proof-of-Principle Pilot Study,” article on the Science Direct website.