This refers to a group of common nonarticular disorders characterized by chronic pain in muscles and soft tissue surrounding the joints. The preferred term fibromyalgia, rather than the older terms fibrositis and fibromyositis, may be justified with the absence of cellular inflammation.

No observable tissue abnormalities are exhibited by persons with the condition. The condition occurs more often in females and may be provoked or exaggerated by unhealthy living conditions, e.g., stress, poor sleep, trauma, or exposure to dampness or cold. Infrequently, the condition may result from a systemic, usually rheumatic, disorder. A viral, or other systemic infection, e.g., Lyme disease (see Diagnostic Code: 6319 Lyme disease) may give rise to the syndrome. Primary fibromyalgia syndrome is a generalized form without a specific recognizable cause that occurs in healthy, young or middle-aged women. It appears in patients who tend to be stressed, tense, depressed, anxious, and striving. However, it may also occur in children or adolescents (usually girls) or in older adults, often associated with unrelated insignificant changes of vertebral osteoarthritis. Men are more likely to develop a localized form of the condition in association with an occupation or recreational activity.

In primary fibromyalgia syndrome (PFS), onset of stiffness and pain is gradual, scattered, and achy. In primary PFS that is confined to a specific area, symptoms are more often abrupt and severe. This pain may be irritated by straining or overuse. Tenderness to a small area may also present, and there may be confined tightness or muscle spasm. Furthermore, underlying systemic conditions may cause inflammation.

Diagnosis is made by recognition of diffuse fibromyalgia symptoms such as: poor sleep patterns, anxiety, fatigue, and irritable bowel symptoms, which are non-rheumatic type symptoms. In addition, significant underlying diseases or disorders, e.g., osteoarthritis, that could be contributory or occurring along with the condition should be excluded as well as psychogenic muscle pain and spasm. In addition, rheumatic disease and hypothyroidism in a middle-aged female should be excluded.

The condition may lessen on its own, or relief may be obtained from counseling related to the nature of the syndrome. In addition, stretching exercises, aerobics, improved sleeping patterns, heat applied to uncomfortable areas, and gentle massage may be helpful. Furthermore, medications for depression, and nonsteroidal anti-inflammatory drugs (NSAIDs) for discomfort may be of assistance to individual patients. Finally, injections of local anesthetic, with or without corticosteroids, may be instituted for debilitating tender areas.

A prediction of a favorable prognosis is the norm if a complete and supportive therapy program is instituted. However, symptoms may persist and recur to some degree at frequent intervals, or become chronic. Referral to specialty resources may be necessary for more intensive patient support, and to manage associated anxiety or depression. National Institute of Arthritis and Musculoskeletal and Skin Diseases - Fibromyalgia

• The rating schedule for musculoskeletal was updated on February 7, 2021. Protection still does apply and should be considered with existing evaluations (38 CFR 3.951(a)).

• For Persian Gulf veterans, this disease shall be granted service connection although not otherwise established as incurred in, or aggravated by service if this condition manifested either during active military, naval, or air service in the Southwest Asia theater of operations, or to a degree of 10 percent or more not later than December 31, 2026; and by history, physical examination, and laboratory tests cannot be attributed to any known clinical diagnosis. 38 CFR 3.317

• May be entitled to special monthly compensation where the veteran has a single service-connected disability rated as 100% with additional service-connected disability or disabilities independently ratable at 60% or more, which are separate and distinct from the 100% service-connected disability and involves different anatomical segments or bodily systems. See  38 CFR 3.350(i)(1) – Special Monthly Compensation (SMC).

• The criteria for evaluation of fibromyalgia under 38 CFR 4.71a, DC 5025 does not exclude assignment of separate evaluations when disabilities are diagnosed secondary to fibromyalgia and provided that the same signs and symptoms are not used to assign separate evaluations under different DCs, per 38 CFR 4.14.

• Assignment of a compensable evaluation under 38 CFR 4.71a, DC 5025 for fibromyalgia with widespread musculoskeletal pain does not prevent assignment of a compensable evaluation under 38 CFR 4.59 for a separately diagnosed disability associated with painful motion of joint or periarticular pathology.

• Widespread pain means pain in both the left and right sides of the body, that is both above and below the waist, and that affects both the axial skeleton (i.e., cervical spine, anterior chest, thoracic spine, or low back) and the extremities. 38 CFR 4.71a [Schedule of ratings-musculoskeletal system]