Fibromyalgia (or Fibrositis)

Definition

Diffuse musculoskeletal aching and pain with multiple predictable tenderpoints.

Main Features

Primary fibromyalgia, without important associated disease, is uncommon compared to concomitant fibromyalgia. It may occur in childhood but is most common in the fourth and fifth decades. The sex ratio is 6:1 female to male. Concomitant fibromyalgia occurs with any other musculoskeletal condition, where it may act to intensify the pain of the associated condition. The syndrome is chronic, and remissions are uncommon.

Pain: Widespread aching of more than three months' duration, often poorly circumscribed and perceived as deep, usually referred to muscle or bony prominences. Most common areas are cervical, thoracic, and lumbar. Although pain in the trunk and proximal girdle is aching, distal limb pain is often perceived as associated with swelling, numbness, or stiff feeling. Day-to-day fluctuation in pain intensity and shifting from one area to another are characteristic, although the pain is usually continuous. Stiffness is present in 80% and is perceived as an increased resistance to joint movement, particularly toward the end of the range of movement. Both pain and stiffness are maximal within the broad sclerotomic and myotomic areas of reference of the lower segments of the cervical and lumbar spine. Fatigue is present in 80%, and is often severe enough to interfere with daily activities. Sleep disturbance is present in 75%, and waking is unrefreshed or tired.

Multiple tender points: Discrete local areas of deep tenderness widely dispersed throughout the body and involving a variety of otherwise normal tissues are a pathognomonic feature provided about 60% of examined sites are tender. Tender points are found within muscle and over tendons, muscle insertions, and bony prominences. Tender point sites are "tender" in many normal individuals but are reported as "painful," often with grimace or withdrawal when palpated, in those with fibromyalgia. The predictable location of these tender points and their multiplicity are essential features of the syndrome.