Clinical term

Fibromyalgia

Fibromyalgia is a chronic pain syndrome combining persistent widespread pain, fatigue, sleep disturbances and often difficulty concentrating, with no tissue damage that could on its own explain the intensity of the symptoms.

Scientific basis

The diagnosis is clinical. It is based on widespread pain present for at least three months, associated with other symptoms such as fatigue, unrefreshing sleep or cognitive difficulties; no laboratory or imaging test confirms it.

Fibromyalgia is now considered the prototypical example of pain linked to a change in how the nervous system processes pain, known as nociplastic pain. It affects about 2% of the adult population, mostly women.

In France, the HAS (French National Authority for Health, 2025) recommends care centered on informing the person, adapted physical activity and a comprehensive approach; medications play only a limited role.

Blue Portance / SBNFA™ reading

SBNFA™ offers neither an explanation for nor a treatment of fibromyalgia. Its analysis is limited to the mechanical, sensory and postural conditions under which sitting takes place: support pressures, how long a position is held, and whether the configuration can be changed.

In a person whose nervous system amplifies signals, these conditions can weigh on sitting tolerance. The SBNFA™ reading therefore looks at what the seat leaves possible for varying support, without claiming to act on the disease.

Contribution to the analysis of sitting

When staying seated becomes difficult, observing how long sitting is tolerated, where support is located and whether movement is possible provides functional information. It does not replace medical care or the recommended adapted physical activity.

Not to be confused with

Central sensitization, a neurophysiological mechanism found in fibromyalgia but also in other chronic pain conditions; neuropathic pain, linked to a lesion of the nervous system; myofascial pain syndrome, pain localized to specific spots in a muscle.

Sources and scope

Established definition, criteria and recommendations (HAS, ACR). This entry does not replace a medical evaluation and describes no effect of a seat on the disease.