Rheumatology and Orthopedics· Topic 17.9 Non-inflammatory and heritable musculoskeletal disorders· 17.9.1

Fibromyalgia

Fibromyalgia is a chronic centralized pain syndrome causing widespread musculoskeletal pain with nonrestorative sleep, fatigue, and cognitive difficulty, driven by central sensitization rather than peripheral inflammation or structural damage. It is a positive clinical diagnosis made with the widespread pain index and symptom severity scale, not a diagnosis of exclusion. First-line treatment is patient education plus a graded aerobic exercise program, with duloxetine, milnacipran, or pregabalin as adjunctive pharmacotherapy.

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What this article covers

  • Overview

    Definition and cardinal presentation: fibromyalgia is a chronic pain-processing disorder causing widespread musculoskeletal pain with fatigue, nonrestorative sleep, and cognitive difficulty ("fibro…

  • Epidemiology

    General prevalence: about 2% to 3% of the population in classic rheumatology series, up to 8% of the US population by broader board-review estimates.

  • Risk factors

    Female sex and family history: female sex is the strongest demographic risk factor, and relatives of affected patients have higher rates of the condition, consistent with twin-study genetics.

  • Pathophysiology

    Central sensitization is the core mechanism: central nervous system hyperexcitability with impaired descending inhibitory pain control generates pain without a nociceptive stimulus, plus allodynia…

  • Clinical features

    Chronic widespread pain: diffuse, multifocal, migratory, waxing-and-waning musculoskeletal pain across multiple body regions, described as widespread arthralgia and myalgia rather than a focal or single-joint process.

  • Differential diagnosis

    Polymyalgia rheumatica: diffuse aching and stiffness, but almost exclusively after age 50, with markedly elevated inflammatory markers and a response within days to low-dose glucocorticoids, unlike…

  • Diagnosis

    First, establish that fibromyalgia is a positive clinical diagnosis, not one of exclusion: made by matching the symptom pattern to validated diagnostic criteria; a diagnosis reached this way does not…

  • Management

    First-line for all patients: education and a graded aerobic exercise program.

  • Complications

    Functional impairment: chronic pain, fatigue, and cognitive difficulty limit work, household, and social function if not actively managed.

  • Prognosis

    Chronic but not destructive: fibromyalgia does not cause synovial damage, joint destruction, or objective tissue injury, distinguishing its course from inflammatory arthritides even though the symptom burden can be substantial.

  • Prevention

    No established primary prevention: fibromyalgia arises from genetic predisposition plus a triggering stressor, and no intervention is proven to prevent it.

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