Much confusion exists about the treatment of trigger points. Some of this confusion has come about because of the way things are labeled. As an example…
The diagnosis of fibromyalgia using criteria established by the American College of Rheumatology lists the “presence of at least 11 of 18 tender points” as an important criterion. Tender points used for the diagnosis of fibromyalgia are not the same as trigger points (TPs). However, trigger points occur in abundance in patients with fibromyalgia.
Trigger points are tender, hard knots occurring in the belly of a muscle. The affected muscle fibers are in a state of sustained physiologic contraction due to what is termed by many as “altered energy states”. Trigger points, when pressure is applied, often cause pain not only in the affected muscle but also in other more distant areas. Trigger points are created by injury or excess muscle strain. The underlying cause of trigger points is abnormal muscle physiology, not an abnormality of central pain processing which is the purported cause of fibromyalgia tender points.
Trigger points are often described as being primary (active), latent, or “satellite”. The primary trigger point is the one that hurts when pressed. Primary TPs develop after injury or strain to the muscle. Latent TPs, on the other hand, are activated by the primary trigger point and refer pain to new areas. Typically these will hurt in an area distant from the primary TP. An example would be the pain associated with a stiff neck. The neck pain can be felt all the way into the back of the head or down between the shoulder blades. The pain that is felt in the back of the head and down between the middle of the shoulder blades is due to activation of latent trigger points. Finally satellite TPs are TPs that are located in normal muscle but are recruited by the active and latent TPs. Satellite trigger points are due to pain amplification where the pain becomes chronic and widespread. An example would be the chest pain that develops after a patient has had longstanding fibromyalgia symptoms in the neck and shoulders.
On exam, TPs feel like hard knots or cords of tissue. They are tender and sore and may cause a patient to “jump.”
The exact mechanism for the development is unknown. Different hypotheses regarding abnormal muscle contraction, reduced oxygen and nutrient flow to the muscle, production of pro-inflammatory cytokines (chemical messengers) such as substance P, and bradykinins, and activation of what are termed “acid-sensing ion channel receptors” are all mentioned as contributors.
The treatment of painful TPs is an individualized process.
Physicians often start with medications.
Since trigger points are primarily a peripheral problem of muscle, peripheral treatments seem to work the best.
Muscle relaxants such as tizanidine (Zanaflex), carisoprodol (Soma), cyclobenzaprine (Flexeril), and metaxalone (Skelaxin) sometimes are effective in reducing muscle contraction.
Non-steroidal anti-inflammatory drugs, while not effective for primary fibromyalgia, may be useful for TP pain when it’s due to acute muscle injury.
Hypnotics (sleeping aids) are helpful for inducing sleep and allowing tissue healing.
Non-drug therapies include moist heat, massage, acupuncture, infrared (cold) laser, and ultra high frequency electrical stimulation. The latter is a relatively new therapy which involves the use of electrical stimulation producing frequencies of 20,000-50,000 beats per seconds. We have found this modality to be exceptionally effective for relief of trigger point pain. [More information about this new therapy can be obtained by calling the Arthritis and Osteoporosis Center of Maryland at (301) 694-5800].
Trigger point injections with local anesthetics and glucocorticoids can often break the pain spasm cycle. More recently, the use of botulinum toxin has found favor with some practitioners.
Centrally acting drugs are usually less effective for typical trigger point pain. However, they are still worth a try as an adjunct to other therapies.
Selective serotonin reuptake inhibitors (SSRIs) and selective serotonin and norepinephrine reuptake inhibitors (SSNIs) can occasionally be useful for TP tenderness. Examples of drugs that fall into this category include Cymbalta, Zoloft, Lexapro, Paxil, Prozac, and Effexor.
Older tricyclic drugs such as amitriptyline (Elavil) can also be useful.
Anti-seizure medicines such as gabapentin (Neurontin) and pregabalin (Lyrica) are sometimes effective.
NMDA receptor antagonists have a central mechanism. An example of an NMDA receptor antagonist is dextromethorphan, an ingredient in many cough preparations. While usually not very effective for peripheral trigger point problems, they may be a useful supplemental therapy when the underlying disease is fibromyalgia.
