SUMMARY: Fibromyalgia is common in all countries studied, and remains commonly litigated in North America. Physical or psychological trauma may be followed by relapse of FMS. Factors other than the presence and severity of FMS determine ability to undertake modified work.

In Canada, 9% of all disability payments are for FibroMyalgia Syndrome (FMS)(1).

In population studies, prevalence of FMS varies from 1 in 200 men to nearly 1 in 10 elderly women(2).

Prevalence is no different in poorer countries (Poland, for instance) or where disability compensation is not available (Israel, for example)(3).

Though the 1994 International Consensus Report (Vancouver, BC)(4) recommended that the term Post-traumatic Fibromyalgia Syndrome be abandoned for clinical research purposes, this condition remains a common focus of personal injury Actions.

Current Understanding

Following is a summary of the present state of Evidence-based knowledge of this condition, from a medicolegal perspective(5):

1. The pre-injury medical records will yield evidence of pre-existing FMS.

2. The following abnormalities may be seen in FMS sufferers: numbers of natural killer cells in the blood(6); alpha-wave intrusion into delta-wave sleep on nocturnal EEG, and serotonin by-products (7), substance P and nerve growth factor in cerebrospinal fluid.

Practice Point

Consider requiring testing of
1. blood for natural killer cells
2. nocturnal EEG for alpha-wave intrusion into delta-wave sleep
3. cerebrospinal fluid for
a. serotonin by-products
b. substance P
c. nerve growth factor

Note that these abnormalities are not routinely tested for clinical purposes.

Spinal tap for cerebrospinal fluid examination has risks that the claimant may not be prepared to take, especially for Defence counsel. However, even routine venepuncture has occasionally Caused cardiac arrest.

3. Physical or psychological trauma may be followed by relapse of FMS. Neither physical trauma nor emotional stress Cause the condition, but both can trigger a relapse.

Practice Point

Trauma and emotional stress do not Cause FMS but either can trigger a relapse lasting weeks to months

4. Post-traumatic symptoms and signs of FMS last for weeks to a few months at most, before returning to baseline.

Practice Point

Obtain medical expert opinion on
1. predisposing factors - stressful life events, chronic medical or psychiatric illness, personality disorder
2. precipitating factors - infection, trauma, emotional stresses
3. perpetuating factors - dislike of work, medical or psychiatric illness, psycho-social problems, sleep disruption, faulty attribution of symptoms

The condition is compatible with full-time employment(8). That is say, it is not sufficient to establish the diagnosis as grounds for disablement, but rather the claimant needs to show why full-time or part-time employment is not possible despite the condition.

The exceptions

In up to 10% of cases, review of 5 years' pre-injury medical records will reveal no evidence of pre-existing symptoms of FMS or myofascial pain syndrome(5).

Such pre-injury records should be routinely available to defence counsel. The court's denial on "fishing expedition" grounds makes no sense: personal injury occurs in a medical context and its outcome can be understood only in that context.

It follows that in a minority of clients widespread pain, with the requisite 11/18 tender points, will appear de novo following compensable trauma.

Symptoms and signs will fluctuate over the succeeding months and years, particularly following further trauma and the usual psychological stresses of life.

Because many life events may Cause relapse, disability that is assessed after many months or even years should not be Causally attributed to the injury. The chronic nature of the condition means that actus novus interveniens is probable.

Related or unrelated psychological conditions, some of which are treatable, may be perpetuating FMS or consequential disability.

Practice Point

Insist on psychological assessment:
1. depressive disorder
2. Post Traumatic Stress Disorder (PTSD)
3. undisclosed childhood trauma
4. pain disorder
5. somatoform disorders
6. personality disorder
7. malingering.

FMS can be malingered. It is self-evident that widespread pain is entirely subjective. It may not be so obvious that litigants can be coached(9) to simulate appropriate tenderness, and to avoid reacting to pressure at "control" tender points.

Factors other than the presence and severity of FMS determine ability to undertake modified work. 90% of FMS patients who desire to work are able to do so(8).

However, a majority have to either change jobs or modify their work activities to accommodate their needs.

Symptoms tend to be worsened by computer work, typing, long periods of sitting, stress, heavy bending and lifting. By contrast, certain activities are well tolerated: walking, light sedentary or desk work, and phoning(10).

The Activities of Daily Living rating is the best instrument currently available for assessment of FMS disability(11).

About a fifth of FMS sufferers collect disability benefits at some stage of their illness(5).

Medico-legal concepts

Currently, a practicable model for FMS is that of pain threshold.

A person's pain sensitivity can usefully be considered to be somewhere on a continuum between very high and very low.

Patients with FMS not only have a low pain threshold, but they experience as painful the sensations of normal fatigue and physical pressure that others experience as pleasurable or neutral (allodynia, Greek for "other pain").

The body chemistry, including that of brain and spinal cord, may be disturbed for some weeks following physical and psychological trauma. Such disturbance can materially lower the pain threshold and, in those with FMS ("thin skull"), the lowering may result in spontaneous pain and disability.

Other Related Articles:

Fibromyalgia 1993
Fibromyalgia 1994
Fibromyalgia 1995-96
Fibromyalgia 1997
Fibromyalgia 1998
Fibromyalgia 1999 - 2000
Chronic Pain

Copyright 2008 Electronic Handbook of Legal Medicine