By Reuben S. Ingber, M.D.
The first medical textbook that took the position that muscles cause pain was published by J. Travell and D.G. Simons in 1983 (1). This is a radical concept of the musculoskeletal system, given the dominance of orthopedic surgeons in the treatment of musculoskeletal injuries. In currently accepted medical theory, structural problems are the only perceived reason for having pain. The concept of myofascial dysfunction, or muscle-connective tissue abnormalities, posits that muscle abnormalities can exist in a painful joint with or without structural abnormalities.
Trigger points are hyperirritable bundles of fibers within a muscle which become “knotted” and inelastic, unable to contract or relax, due to an injury. The hallmarks of the physical examination are marked muscle tenderness, muscle and fascial hyperirritability phenomenon, loss of range of motion and muscle weakness. Shortening and loss of range of motion, which is observed in injury to a muscle when muscles are strained or used eccentrically, may be the harbinger of the myofascial dysfunction.
Myofascial treatment in the form of injection of lidocaine, dry needling or deep muscle massage followed by a specific, supervised, therapeutic stretching program aims to re-establish a painless, full range of motion.
Since the 1983 publication of the textbook, Myofascial Pain and Dysfunction the Trigger Point Manual by J. Travell and D.G. Simons (1), trigger point injections, like other medical procedures, have been both used and unfortunately abused. In 1995, development of guidelines for the management of acute low back pain was sponsored by the U.S. Department of Health and published in November(2).
The guidelines were compiled by a panel of experts from the AHCPR. The majority of the physicians on that panel were surgeons, either orthopedic surgeons or neurosurgeons; their recommendations are accordingly and significantly biased. Based upon a skewed reading of the literature, they concluded that trigger point injections are not effective. Since no clinical controlled trials have demonstrated the effectiveness of trigger point therapy for low back pain or lumbar radiculitis, the panel recommended against the continued use of trigger point injections in the treatment of low back pain or lumbar radiculitis. Yet no trials demonstrated ineffectiveness either.
Of several clinical controlled trials of lumbar epidural corticosteroid injections, only one demonstrated some effectiveness for three months after the injection. Nevertheless, the AHCPR panel did recommend its use in treating lumbar radiculitis even though “there was no evidence that epidural steroids are effective in treating acute radiculopathy, but the panel’s opinion was that epidural steroid injection may be useful as an attempt to avoid surgery” (page 48). The bias is evident in the faulty logic.
Based on the panel’s recommendations, HCFA issued its guidelines, and as a result, several states have stopped Medicare reimbursement for trigger point injections in the treatment of any spinal problem, cervical or lumbar. It is likely that many other states will follow suit, as undoubtedly will many insurance companies. This lack of backing will inevitably lead to the peripheralization of what seems to be a very valuable, potentially highly effective and riskless medical procedure which aims to treat a muscle when a musculoskeletal diagnosis is made.
Simply stated, the theory of myofascial pain posits that when a person has, for example, tendonitis, a muscle treatment will effectively eliminate the problem or predisposing perpetuating problem, and will be just as effective as a cortisone injection in returning the normal function of a joint.
To date, very little is known about trigger point injections–how
effective are the treatments, how many injections, which muscle(s) to inject, what corrective maneuvers need to be made after a trigger point injection. The reason for the gap in our knowledge is that very little funding has gone into the research of these treatments, as there is very little financial incentive for anybody to sponsor such research efforts. In the thirteen years since the original publication of the myofascial dysfunction textbook by J. Travell and D.G. Simons, no clinical studies with proper controls have been published.
II. Research to Date
What little research we do have proves that trigger points do exist and are not a figment of the imagination of some very enterprising physicians. Studies by Ngoo et al.(3) (1994) and Gerwin et al.(4)(1997) have shown good interrelator reliability when examining for trigger points, if experienced and trained personnel are conducting the examination. Controlled studies have also demonstrated that effective treatment can be achieved with different trigger point injection techniques, as studied by Garvey et al.(5)(1989). In that study, dry needling was shown to be as effective as injection of either lidocaine or a combination of lidocaine and cortisone in the treatment of a group of low back pain patients.
Hong (6) in 1994 demonstrated that injection of lidocaine and dry needling were equally effective but dry needling caused more complaints of soreness in the period immediately following trigger point injection. More significantly, Hong pointed out that achieving a local twitch response with the needle was the most important factor in achieving an effective response, more important than what type of treatment was utilized, i.e., dry needling vs. injection of lidocaine.
No controlled studies are available on the clinical response to trigger point injections. No studies have been done, for example, to measure the clinical response of a group of patients with low back pain or lumbar radiculitis to trigger point injections to a specific muscle.
One controlled study by Aleksiev and Kraev (7) in 1994 of low back pain patients, comparing myofascial release to thrust manipulation, shows them to be equally effective in relieving low back pain. We cannot say with certainty which muscle or muscles are most important to treat a specific diagnosis, or whether response in trigger points is enhanced by post-injection stretching exercises. These are important questions that need to be answered.
There are, however, case reports of failed low back pain treated with iliopsoas myofascial treatments (8)(Ingber, 1989), a series of patients with low back pain treated with dry needling (9)(Gunn, 1980), a series of patients with lumbar radiculitis treated with dry needling (10)(Chou, 1995), a series of patients with lumbar radiculitis treated with iliopsoas dry needling (11) (Ingber[abstract], 1996), a series of patients with shoulder pain treated with subscapularis myofascial treatments (12)(Ingber[abstract], 1986) and a case of atypical chest pain caused by a trigger point in the diaphragm muscle (13)(Ingber[abstract], 1988). Lewit (14)(1979) reported on various musculoskeletal problems treated with dry needling.
There have also been case reports presented at the annual meetings of the American Academy of Physical Medicine and Rehabilitation, including reports of myofascial diagnoses and treatments for unusual abdominal and pelvic pains, runners with shin splints, compartment syndromes and Achilles tendonitis, tennis players with shoulder impingements, and musicians with focal hand dystonias.
The physicians who have presented cases of myofascial problems mimicking musculoskeletal syndromes that go by other names are not misguided clinicians out to steal orthopedic patients. They are astute clinicians who are trying to bring to the fore their observations in a very important area of musculoskeletal treatment that has been, to date, under-recognized and under-studied. Frequent calls for clinical control trials have gone out in the hope that efficacy compared to standard treatment can be demonstrated, but funding and enthusiasm from the medical hierarchy are grossly lacking.
Many physiatrists feel that trigger point injections should continue to be reimbursed by all medical carriers for all musculoskeletal disorders, with the number of trigger point injections limited to a series of 3 to 4. A second series of 3 to 4 would be allowed with demonstration of response by history and physical examination by written report. Further trigger point injections would be allowed only on a case-by-case basis, reviewed by appropriately trained medical personnel from the insurance carrier. The status quo ante should remain and should continue for a period of five years. These limitations would be acceptable to many physiatrists, provided that governmental agencies encourage the immediate institution of research in the area of myofascial pain.
The government, through the NIH or AHCPR (Agency for Healthcare Research and Quality), should launch this research with a conference on myofascial pain modeled after the alternative methods conference sponsored by the NIH in October 1995. A panel of medical scientists and experts in fields as varied as anatomy, kinesiology, and orthopedics specializing in muscles, osteopathy and physiatry would be assembled to analyze and assist with the more promising proposals. Everyone would be invited to present approaches and ideas regarding myofascial pain. Then, several studies could be initiated, acceptable to all factions in the medical and non-medical community, to see if any significant improvement can be achieved through acceptable clinical trials.
Recent years have seen an epidemic of musculoskeletal injuries such as repetitive stress injuries, carpal tunnel syndrome, runner’s shin and knee pains, cervical whiplash injuries and lumbar disabilities. The number and variety of cures and treatments for pain (pain clinics, pain blocks, work-hardening, Botox injections) have also exploded. The cost of musculoskeletal injuries, both in direct medical bills and in lost productivity, is crippling Western industrialized countries.
If Solomonow’s observation (15) of the important “role of the muscles associated with the joint in maintaining its integrity” is correct, then myofascial treatments may be an important box currently missing from the treatment algorithms for musculoskeletal pain.
1. Travell JG, Simons DG. Myofascial Pain and Dysfunction: The
Trigger Point Manual. Baltimore, Williams & Wilkins, 1983.
3. Njoo KH, Van der Does E: The occurrence and inter-rater
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lumborum and gluteus medius: a prospective study in non-specific
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Identification of myofascial trigger points: inter-rater
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double-blind evaluation of trigger point injection therapy for
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response: Am J Phys Med Rehabil 73: 256-263, 1994.
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velocity low amplitude techniques in low back pain. J Orthop Med
16: 38-41, 1994.
8. Ingber, RS. Iliopsoas myofascial dysfunction: a treatable
cause of “failed” low back syndrome. Arch. Phys. Med. Rehabil.
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muscle motor points for chronic LBP. Spine 5:279-291, 1980.
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12. Ingber, RS. Myofascial dysfunction of the subscapularis as a cause of shoulder pain (abstract). Arch. Phys. Med. Rehabil. 67:616, 1986.
13. Ingber, RS. Atypical chest pain due to myofascial dysfunction of the diaphragm muscle: a case report (abstract). Arch. Phys. Med. Rehabil. 69:729, 1988.
14. Lewit K: Needle effect in relief of myofascial pain. Pain
15. Baratta R, Solomonow M, Zhou EE, et al.: Muscular coactivation. The role of the antagonist musculature in maintaining knee stability. Amer J Sports Med 16: 113-122, 1988.