In 1952, Drs. Travell and Rinzler published an article outlining referred pain patterns for 32 muscles. Many years later, Travell, along with Dr. David Simons, published the Trigger Point Manuals, which describe the referred-pain patterns of nearly 150 muscles and extensive review of the neurophysiological mechanisms of muscle trigger points.
Manual treatments for trigger-point pain have been used effectively by physical therapists for many years. And in ever growing numbers, physical therapists are embracing the technique of dry needling, also known as intramuscular manual therapy, for the treatment of pain and dysfunction. The state boards of physical therapy of 19 states and the District of Columbia have approved dry needling in their scope of practice.
However, this decision has been challenged by some members of the acupuncture community, including the American Association of Acupuncture and Oriental Medicine (AAAOM), who contend that dry needling should not be in the scope of physical therapy practice and that the insertion of needles should be reserved for licensed acupuncturists and physicians.
Inactivating Trigger Points
Traditional Chinese medicine, from which acupuncture originated, is based on a framework of metaphysical concepts, beliefs in the supernatural and demonology, combined with natural laws. According to The Yellow Emperor's Classic of Internal Medicine, acupuncture began as a form of blood-letting, intended to maintain balance between the spiritual and natural worlds. It was performed by non-medical healers who used sharp stones as their tool.
Early acupuncture incorporated the concepts of meridians, energy flow (qi), and five elements, and this focus remained throughout the Middle Ages. Acupuncture was outlawed in China in 1822 and was not reintroduced as an accepted approach to healing until the mid-1930s. At that time, the use of thin filaments replaced sharp stones and course needles.
Modern definitions of acupuncture are varied. The Maryland Acupuncture Act and the Delaware and Florida statutes define acupuncture as "a form of health care, based on a theory of energetic physiology that describes and explains the interrelationship of the body organs or functions with an associated acupuncture point or points located on meridians." Acupuncture needles are inserted over an acupoint, or region where meridians come to the surface of the skin, to restore qi, or vital energy.
More than 2,000 acupoints on the body have been described, each corresponding to different conditions to treat. A version of acupuncture, adopted by European and American practitioners, discards the notion of energy flow and ancient ideology. This Western medical acupuncture is based on current concepts of pathology and evidence-based medicine as well as knowledge of anatomy and physiology. The goal of this form of acupuncture is to decrease pain through the modulation of peripheral and central nervous systems, including activation of descending inhibitory pathways.
The main goal of dry needling is to inactivate the myofascial trigger points, but the technique is also used to treat scar tissue, tendonitis and adhesions. With myofascial pain, thin filaments are inserted below the skin and into a palpable contracture knot within a taut band of muscle. If the technique is performed correctly, a local twitch response will occur, which is a spinal cord reflex contraction of the muscle fibers.
Researchers have documented the presence of a "chemical soup" of inflammatory mediators, neuropeptides, cytokines and catecholamines surrounding the trigger point. The elicitation of a local twitch response leads to immediate reduction of these nociceptive substances, possibly secondary to an increase in blood flow.
Identifying Trigger Points
It has been theorized that dry needling destroys the motor end plate, triggering normal muscle regenerative processes. Dry needling has been shown to reduce peripheral sensitization as well as central sensitization, by modulating descending inhibitory pathways and enhancing activity in the areas of the brain involved in pain reduction and a sense of well-being. A variation of dry needling, developed by Baldry, is superficial dry needling, in which the needle is inserted 5-10 mm below the surface of the skin. The needle is placed over the contracture knot and held in place for 30 seconds. If pain remains after 30 seconds, the needle is reinserted for an additional two to three minutes. This technique may activate C fiber tactile afferents and reduce pain via the central release of oxytocin.
Although acupuncture applies the basic tenets of traditional Chinese medicine, and dry needling has no basis in Oriental medicine, several researchers have attempted to establish a scientific correlation between acupuncture points and trigger points. In 2009, Dorsher published an article demonstrating overlap between meridians and myofascial trigger points. He based his findings on the belief that myofascial trigger points have specific anatomical locations, as Travell and Simon indicated in their Trigger Point Manuals. However, no scientific evidence supports this notion. It's more likely that referred pain patterns are specific to whole, or parts of, muscles.
Melzack et al, in 1977, reported a 71-percent overlap between acupuncture points and trigger points, but a reassessment by Birch revealed "questionable" assumptions, including the proper identification of myofascial trigger points. Furthermore, Melzack failed to include "Ah Shi" points in his study. Ah Shi points are one of three major classes of acupuncture points, the other two being channel points (of which there are 361), and "extra" points.
It is the Ah Shi point that contains pressure pain and is used for pain and spasm conditions, and it has been speculated that acupuncturists treating these points may well be treating myofascial trigger points.
Langevin developed a scientific rationale for the therapeutic effects of acupuncture. She hypothesizes that a phenomenon known in acupuncture practice as "de qi" occurs when "the needle is being grasped by connective tissue as a result of collagen and elastic fibers winding and tightening around the needle, transmitting a mechanical signal to connective tissue cells via mechanotransduction," leading to local cellular responses and downstream effects. While the primary aim of dry needling is the inactivation of trigger points, these concepts of mechanotransduction and cellular changes may apply.
Role of the Physical Therapist
In clinical studies that attempted to establish whether or not acupuncture points have distinct and reproducible clinical indications, researchers compared the effects of needling known acupuncture points and sham points (superficial needling of non-acupuncture points). Both were found to be more effective in reducing pain than no treatment, probably because any needling creates a physiological effect, including the release of endorphins, lowering of the pain threshold, and the expectancy of a positive outcome. These phenomena apply also to dry needling.
The AAAOM, the national organization that represents all acupuncturists in the United States, has stated in a letter submitted to the District of Columbia Board of Medicine that dry needling constitutes acupuncture. The group asserts that "physical therapists are attempting to include acupuncture in their scope by calling it a different name, thereby circumventing the extensive training required by both physicians and acupuncturists." They further assert that physical therapists are not adequately qualified to perform this procedure, and that this "creates a serious endangerment to the public."
The AAAOM assumes that any use of acupuncture needles would fall exclusively in the scope of acupuncture practice. Several federations of state boards concluded that an overlap of scope of practice is inevitable and may actually be beneficial for patients. In more than two decades of dry needling in the U.S., there are no reports of adverse effects. As for qualifications, physical therapists have significantly more education in anatomy than acupuncturists. Georgia State University and Mercer University (both in Atlanta, GA) include dry needling in their entry-level DPT and physical therapy residency programs, respectively. Other universities are considering the same.
For now, as with other advanced techniques, dry needling training is offered primarily as a continuing education series. In light of these perspectives, the question for state boards of physical therapy should not be whether or not dry needling constitutes acupuncture, but rather, whether or not dry needling is within their scope of practice.
Louise Kelley and Jan Dommerholt are practitioners at Bethesda Physiocare in Bethesda, MD.
Treating pain and numbness of the hands and wrists with trigger point
work, such as myofascial release, ischemic compression, static pressure
and deep muscle massage therapy on the forearm, shoulder, neck and
back, results from research by Janet Travell, MD, and David Simons, MD.
Their work established that trigger points are the cause of most common
myofascial pain problems.
Drs. Travell and Simons describe a trigger point as a small
contraction knot in muscle tissue. It often feels like a pea buried deep
in the muscle, which keeps the muscle tight and weak. Trigger points
also maintain a hard contraction on the muscle fibers that are directly
connected to them. These taut bands of muscle fiber keep constant
tension on the muscle's attachments, often producing symptoms in
In addition to the aforementioned effects, trigger points can also
cause hypersensitivity, muscle weakness, joint stiffness and a variety
of autonomic symptoms. When these symptoms occur in the hands, patients
and physicians often mistakenly assume that arthritis, bursitis,
tendinitis, CTS or a neurological defect is the culprit. Clinicians can
fall into the same trap when they don't recognize myofascial symptoms.
Trigger points in the scalene, brachialis and forearm muscles are the
most common cause of symptoms in the hands. Other muscles in the upper
back, shoulders, arms and hands may sometimes be involved.
An effective way to treat trigger points involves combining
compression and slow, deep massage strokes. By applying a series of
strokes directly to the trigger point nodule, you can achieve results
faster than using the static pressure of ischemic compression alone.
This technique results in less irritation to the trigger point and less
referred pain to the patient.
Move slowly over the trigger point, about one stroke every 2 seconds.
Each stroke needs to be about an inch long-enough to move from one side
of the trigger point to the other. Instead of sliding your finger
across the skin, move the skin with the fingers. Release at the end of
the stroke, go back to where you started, reset and repeat.
Each time you release the pressure, fresh blood flows into the spot
and brings a renewing charge of oxygen and nutrients. This action is
important because the knotted muscle fibers have been strangling the
surrounding capillaries and depriving the area of these essential
By combining massage therapy with stretching and strengthening
exercises, you can get a handle on trigger points and allow the body to
heal itself from this common source of pain.
Morgan E. Miller is a certified massage therapist, licensed skin
therapist, and owner of Elements to Wellness, a massage therapy and skin
center in Reading, PA.