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(Myofascial Pain Syndrome)


Joseph J. Biundo

, MD, Tulane Medical Center

Last full review/revision Feb 2020| Content last modified Feb 2020
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Fibromyalgia is a common, incompletely understood nonarticular disorder characterized by generalized aching (sometimes severe); widespread tenderness of muscles, areas around tendon insertions, and adjacent soft tissues; muscle stiffness; fatigue; mental cloudiness; poor sleep; and a variety of other somatic symptoms. Diagnosis is clinical. Treatment includes exercise, local heat, stress management, drugs to improve sleep, and nonopioid analgesics.

In fibromyalgia, any fibromuscular tissues may be involved, especially those of the occiput, neck, shoulders, thorax, low back, and thighs. There is no specific histologic abnormality. Symptoms and signs of fibromyalgia are generalized, in contrast to localized soft-tissue pain and tenderness (myofascial pain syndrome Myofascial Pain Syndrome Myofascial pain syndrome (previously known as myofascial pain and dysfunction syndrome [MPDS or MFPDS]) can occur in patients with a normal temporomandibular joint. It is caused by muscle tension... read more ), which is often related to overuse or microtrauma.

Fibromyalgia is common; it is about 7 times more common among women, usually young or middle-aged women, but can occur in men, children, and adolescents. Because of the sex difference, it is sometimes overlooked in men. It often occurs in patients with other concomitant, unrelated systemic rheumatic disorders, thus complicating diagnosis and management.

Etiology of Fibromyalgia

Current evidence suggests fibromyalgia may be a centrally mediated disorder of pain sensitivity. The cause is unknown, but disruption of stage 4 sleep may contribute, as can emotional stress. Fibromyalgia may be precipitated by a viral or other systemic infection (eg, Lyme disease Lyme Disease Lyme disease is a tick-transmitted infection caused by the spirochete Borrelia species. Early symptoms include an erythema migrans rash, which may be followed weeks to months later by neurologic... read more Lyme Disease ) or a traumatic event, but additional or prolonged antiviral or antibiotic therapy is not indicated because it is not effective.

Symptoms and Signs of Fibromyalgia

Stiffness and pain frequently begin gradually and diffusely and have an achy quality. Pain is widespread and may worsen with fatigue, muscle strain, or overuse.

Symptoms can be exacerbated by environmental or emotional stress, poor sleep, trauma, exposure to dampness or cold, or by a physician, family member, or friend who implies that the disorder is “all in the head.”

Patients tend to be stressed, tense, anxious, fatigued, ambitious, and sometimes depressed. Patients are not uncommonly high-achieving perfectionists.

Physical examination is unremarkable except that specific, discrete areas of muscle (tender points) often are tender when palpated. The tender areas are not swollen, red, or warm; such findings should suggest an alternative diagnosis.

Diagnosis of Fibromyalgia

  • Clinical criteria

  • Usually testing and a detailed physical examination to exclude other disorders

Fibromyalgia is suspected in patients with the following:

  • Generalized pain and tenderness, especially if disproportionate to physical findings

  • Negative laboratory results despite widespread symptoms

  • Fatigue as a predominant symptom

The diagnosis of fibromyalgia should be considered in people who have had widespread pain for at least 3 months, particularly when accompanied by various somatic symptoms. Pain is considered widespread when patients have pain in the left and right side of the body, above and below the waist, and in the axial skeleton (cervical spine, anterior chest or thoracic spine, or low back).

The diagnosis is based on clinical criteria from the American College of Rheumatology (1 Diagnosis reference Fibromyalgia is a common, incompletely understood nonarticular disorder characterized by generalized aching (sometimes severe); widespread tenderness of muscles, areas around tendon insertions... read more ), which include a combination of widespread pain and the presence of various other cognitive and somatic symptoms, such as those listed above, which are graded in severity. Previous criteria relied on the presence of tenderness at some of 18 specified tender points. This criterion was eliminated because nonspecialists sometimes have difficulty evaluating tenderness consistently, the tender points may fluctuate in intensity, and it was thought advantageous to have criteria that are entirely symptom-based. However, tenderness is quite common, and some specialists continue to assess it systematically.

Tests for other causes of patient symptoms should include erythrocyte sedimentation rate (ESR) or C-reactive protein, creatine kinase (CK), and probably tests for hypothyroidism Diagnosis Hypothyroidism is thyroid hormone deficiency. It is diagnosed by clinical features such as a typical facial appearance, hoarse slow speech, and dry skin and by low levels of thyroid hormones... read more Diagnosis and hepatitis C Diagnosis Hepatitis C is caused by an RNA virus that is often parenterally transmitted. It sometimes causes typical symptoms of viral hepatitis, including anorexia, malaise, and jaundice but may be asymptomatic... read more (which can cause fatigue and generalized myalgias). Other tests (eg, serologic testing for rheumatic disorders) should be done only if indicated by findings on history and/or physical examination.

To avoid potential pitfalls, clinicians should consider the following:

Diagnosis reference

Prognosis for Fibromyalgia

Fibromyalgia tends to be chronic but may remit spontaneously if stress decreases. It can also recur at frequent intervals. Functional prognosis is usually favorable for patients being treated with a comprehensive, supportive program, but symptoms tend to persist to some degree. Prognosis may be worse if there is a superimposed mood disorder that is not addressed.

Treatment of Fibromyalgia

  • Stretching and aerobic exercise, local heat, and massage

  • Stress management

  • Tricyclic antidepressants or cyclobenzaprine to improve sleep

  • Nonopioid analgesics

Stretching exercises, aerobic exercises, sufficient sound sleep, local applications of heat, and gentle massage may provide relief. Overall stress management (eg, deep breathing exercises, meditation, psychologic support, counseling if necessary) is important.

Exercises to gently stretch the affected muscles should be done daily; stretches should be held for about 30 seconds and repeated about 5 times. Aerobic exercise (eg, fast walking, swimming, exercise bicycling) can lessen symptoms.

Improving sleep is critical. Sedating drugs can be taken but only at night and only to improve sleep. Low-dose oral tricyclic antidepressants at bedtime (eg, amitriptyline 10 to 50 mg, trazodone 50 to 150 mg, doxepin 10 to 25 mg) or the pharmacologically similar cyclobenzaprine 10 to 30 mg may promote deeper sleep and decrease muscle pain. The lowest effective dose should be used. Drowsiness, dry mouth, and other adverse effects may make some or all of these drugs intolerable, particularly for older patients.

Nonopioid analgesics (eg, acetaminophen, nonsteroidal anti-inflammatory drugs [NSAIDs]) may help some patients. Opioids should be avoided. Pregabalin, duloxetine, and milnacipran are available for treatment of fibromyalgia, but should be used as adjuncts to exercise, measures to improve sleep, and stress management; they may help modestly to reduce pain.

Occasional injections of 0.5% bupivacaine or 1% lidocaine 1 to 5 mL are used to treat incapacitating areas of focal tenderness, but such injections should not be relied on as primary treatment because evidence does not support their regular use.

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