Chronic Widespread Pain (FibroMyalgia Syndrome)

Fibromyalgia is common in women, whether or not they are pursuing personal injury claims.

Fibromyalgia is common in all countries studied, and remains commonly litigated in North America.

FMS appears to be mediated by a pathologically lowered pain threshold. Nerve cells may be chemically sensitised to pain signals.

Although the pathological basis for the lowered pain threshold is better understood than previously, medical causation remains unknown.

Injury may or may not be responsible for subsequent FibroMyalgia Syndrome.

Physical or psychological trauma may be followed by relapse of FMS.

Like most common bodily symptoms, chronic widespread pain usually does not have a serious cause.

Legal causation can be analysed with greater consensus than before.

Various treatments have a limited effect on prognosis. Psychosocial factors are more powerful predictors of improvement or recovery.

Chronic widespread pain sufferers who blame localised soft-tissue injury have more severe symptoms and greater disability. There is little scientific basis for such causal attribution.

Some symptoms are more resistant than others to Multidisciplinary Therapy, and how much an individual client will benefit can be incompletely predicted.

Neither physicians nor psychologists have valid tools for assessing disability caused by chronic widespread pain.

Disability in chronic widespread pain is determined not by intensity of pain but by psychological and social factors.

Compensation for chronic widespread pain is a matter for legal and social consideration, and medicine has little to contribute beyond compassion.

Physical medicine specialists are currently being asked to advise the courts on conditions that are better addressed by experts in mental conditions.

Determination of Causation requires more far-reaching multidisciplinary assessment than is often undertaken.

Even psychiatrists’ and psychologists’ expertise is in more accurate diagnosis rather than assessment of disability.

For most FMS patients there are significant discrepancies between self-report and observed functioning.

Poorly functioning sufferers represent a significant proportion of people identified as psychiatrically disabled. Such clients have a mind-set that pain alone causes disability.

From the medicolegal perspective, Fibromyalgia is best considered as a particular variety of Widespread Chronic Pain.

CRITERIA¹: 1) Widespread pain in combination with 2) tenderness at 11 or more of the 18 specific tender point sites.

Any accompanying abnormalities on xray or laboratory investigation are irrelevant.

These criteria identified nearly 90% of patients with fibromyalgia and excluded all but 19% of those suffering from disorders which could be confused with fibromyalgia.

According to the 1990 American College of Rheumatology criteria and the 1990 census data, 0.5% of men, 3.4% of women and more than 7% of older women fulfilled the generalised pain and tender point criteria for FibroMyalgia Syndrome (FMS)³.

Prevalence is no different in poorer countries (Poland, for instance) or where disability compensation is not available (Israel, for example)⁴.

In Canada, 9% of all disability payments are for FibroMyalgia Syndrome (FMS)⁵.

Sufferers not seeking medical attention are less distressed than patients, but more distressed than people without chronic widespread pain⁶.

A wide diversity of symptoms that accompany generalised chronic pain are similarly prevalent in those without disease or injury⁷.

Pathology

As well as lower pain threshold, FMS sufferers have tenderness of skinfolds, increased skin redness in response to pressure, and greater resistance to compression of some muscles⁸.

Although only pressure is routinely tested, the general sensitivity to other painful stimuli (cold⁹ and heat) is also increased, and, for electrical pain, just at tender points¹⁰.

The mechanism of the lowered threshold for appreciation of pain (nociception) and tenderness appears to involve a primary abnormality of neurochemicals¹¹, messengers that amplify (pro-nociceptive) or suppress (anti-nociceptive) pain signals¹².

Animal experiments^13,14 have shown that the pro-nociceptive chemical known as Substance P normally alerts nerve cells in the spinal cord to incoming pain signals.

In FMS, the CerebroSpinal Fluid (CSF) that bathes the brain and spinal cord has greater than normal concentrations of Substance P¹⁵, in the order of a 3-fold increase¹⁶.

In patients tested on two occasions, an average of a year apart, their symptoms and the concentrations of Substance P in the CSF increased in tandem.

Similarly, by-products of the neurotransmitter Serotonin are reduced in amounts¹⁷.

There is a hitherto unconfirmed report that FMS patients also have increased CSF concentrations of Nerve Growth Factor¹⁸. This neurotransmitter is believed to enchance the growth of nerve cells that contain Substance P.

There is also accumulating evidence¹⁹ that various anti-nociceptive substances are in short supply in FMS patients.

Magnetic Resonance Imaging has been added to the list of investigations - biochemical, histological, xray - which are unable to demonstrate an abnormality in the muscles of fibromyalgia sufferers²⁰.

However, ElectroMyoGraphy (EMG, experimental recording of the electrical activity in muscles) demonstrated that tender areas of muscle contained muscle fibres which were in a state of spontaneous contraction²¹.

The researchers proposed that this spontaneous contraction arose out of an overactivity of the sympathetic nervous system ("fight or flight" response) which normally controls the activity of muscles in the internal organs.

Paradoxically, the body's production of stress hormones is actually reduced²².

The deepest stage (four) of sleep is disturbed in fibromyalgia²³. This is the sleep stage in which most growth hormone is produced by the body. Growth hormone is necessary for the repair and maintenance of healthy muscles.

Fibromyalgia patients have increased amounts of alpha-wave non-Rapid Eye Movement (non-dreaming) sleep²⁷, and their sleep-cycle is disorganised²⁴.

In the waking state, painful stimulation causes larger brainwaves(evoked potentials)¹⁰ than normal.

Natural killer cells (T lymphocytes) in the blood are reduced²⁵.

Other laboratory researchers have been clarifying the development of antibodies²⁶ which might attack the patient’s own tissues.

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

The central clinical abnormality in FibroMyalgia Syndrome is chronic, widespread allodynia (Greek for "other pain") - pain arising from a stimulus that is not normally experienced as painful¹⁹.

Just as birth-weight and blood-pressure fall in a range that is roughly normally distributed ("bell-shaped curve"), so do dolorimetry scores²⁸ - the average amount of local pressure required to cause transition from sensation of pressure to sensation of pain.

Just as people whose blood pressures are at the upper end of the range have more illness and higher death-rates, those who have high dolorimetry scores have greater pain and more disability.

If the resultant allodynia is unrelieved, physical deconditioning and daily minor trauma complete the vicious circle and cause self-perpetuating (legal) Impairment and Handicap.

Clinical research²⁹ in Israel showed a thirteenfold probability after cervical spine injury compared with leg fracture.

In one view, Fibromyalgia arises from difficulties in coping with various types of environmental stress.

Sleep disturbances, fatigue, a low level of physical activity and poor physical fitness result, making patients susceptible to muscle pain³⁰.

A Canadian judge^** preferred the evidence of a psychiatrist that Fibromyalgia was a form of Hysterical Conversion^**. She discounted the opinion of a rheumatologist because of his "personal and perhaps financial interest in perpetuating the existence of this condition."

Another rheumatologist and a specialist in physical medicine and rehabilitation have argued that Post-Traumatic Fibromyalgia is not a disease entity because it fails all eight rules of medical causation³¹.

They proposed rather that the symptoms are an expression of psychosocial distress.

The 1990 report¹ of the American College of Rheumatology criteria for Fibromyalgia did not address the role of trauma. The first recommendation of much the same working group in their 1994 Consensus Report³² was that the terms "reactive" and "post-traumatic" be eliminated.

Evidence Based Medicine^** does not support the contention that localised trauma causes Chronic Widespread Pain^****.

The finding that cervical spine injury was thirteen times more likely to be followed by FMS than leg fracture^** remains the only quality study supporting a traumatic cause.

Although neither physical trauma nor emotional stress Cause the condition, both can trigger a relapse³³.

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

Some people have an increased liability to somatise³⁴.

Among general practice patients, between two and three out of every five patients complain of symptoms that have no serious basis.

Even among general medical outpatients, less than 20% of those with the most common bodily symptoms proves to have a physical cause.

Injury may provide a focus for attribution of those symptoms. As with Low Back Pain and neck pain^**, the occurrence of compensable injury may cause patients to misattribute chronic or recurrent widespread pain that they do not recall as pre-existing.

Thus a practicable medico-legal 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.

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.

In our current state of ignorance, a recently publicised model³⁵ may help litigators analyse legal causation.

Precipitating events are generally severe infectious illness, physical trauma (surgery, accidental) and severe emotional stress.

Perpetuating factors may be unrecognised by clients and inadequately treated by their caregivers.

Patients with larger numbers of tender points tend to have greater problems with sleep, fatigue and depression³⁶.

Women with fibromyalgia scored lower on various measurements of quality of life than women with rheumatoid arthritis, permanent ostomies, chronic obstructive lung disease and insulin dependent diabetes³⁷.

Despite similar physical findings, and controlling for compensation status, so-called Post-Traumatic Fibromyalgia patients suffered more pain, disability, life-interference and emotional distress than those who had not experienced preceding trauma³⁸.

They similarly were more likely to be consuming narcotics and to have tried a variety of pain-killing alternatives.

A US team found³⁹ that it was not the severity of symptoms or functional limitations but a perception that the illness was caused by physical trauma (not emotional) which characterised compensation claimants.

Another team at Ben Gurion University⁴⁰ found that a fifth of sufferers from Post Traumatic Stress Disorder fulfilled criteria for Fibromyalgia. The researchers proposed that much of the Chronic Pain common in PTSD was undiagnosed Fibromyalgia.

As part of a study⁴¹ of Fibromyalgia and Rheumatoid Arthritis, Canadian psychiatrists analysed the factors in patients which caused physicians to experience patients as frustrating.

Somatisation, perception of having no control over illness, and lifetime experience of Obsessive-Compulsive Disorder accounted for half the factors.

Self-management education programmes enhanced self-esteem and quality of life⁴², but strenuous physical training had a longer-lasting benefit⁴³.

Aerobic walking for 20 minutes thrice weekly had doubtful benefit⁴⁴.

In the short-term, the antidepressant Amitryptiline was more effective than Cyclobenzaprine, but by 6 months there was no significant advantage over sugar-pills⁴⁸.

The antidepressant Fluoxetine (Prozac) increased the benefit of Cyclobenzapine⁴⁹, but was ineffective alone⁵⁰.

It is probable, but not certain, that this benefit on FMS is independent of the improvement in depression⁴⁶.

However, the benefits of tricyclic antidepressant medication are usually lost by 2-3 months⁴⁸.

A 2-4 week drug holiday using an alternative medication may re-establish effectiveness⁵¹.

Tranquillisers of the Valium type (benzodiazepines) can be used for such a drug holiday, as they too have been shown to be effective in reducing tenderness and improving functional and psychological status⁵².

Sleeping-pills were also effective⁵³.

Such medications are unsuitable for long-term use because they readily cause psychological and physical dependence, including withdrawal seizures.

However, a third of patients appear to have a correctable reduction in the production of Growth Hormone (GH) from the pituitary gland.

These findings are presently experimental, preliminary and unconfirmed, but GH-replacement may in time alter the treated prognosis for a significant minority of FMS patients.

Narcotics such as Demerol may prove to be effective for intractable non-cancer pain, but they should similarly be avoided in a chronic condition such as FMS, because of the addiction potential.

Various other pharmacological agents, some of which are frequently prescribed, have now been tested and found to be ineffective in FMS⁴⁵: Non-Steroidal Anti-Inflammatory Drugs (NSAIDs), Cortisone-like medications (corticosteroids), and injected local anesthetics such as Xylocaine

With no specific intervention, 1 in 4 patients had overall improvement by 5 years, but a half were worse, and for the majority continuing symptoms severely limited everyday life activities⁵⁵.

A long-term study⁵⁶ of 39 patients found that symptoms of Fibromyalgia Syndrome improved somewhat in the majority but persisted at least 15 years on average.

The belief in a precipitating event, rather than acceptance of a medical condition of uncertain cause, appears to both amplify symptoms and increase disability⁵⁷.

Over years, physical treatments tended to be discarded, but more than a half were using over-the-counter painkillers, over a third were on antidepressants, and the vast majority continued to have significant symptoms and clinical evidence of Fibromyalgia⁵⁸.

Conversely, years after a management programme, nearly half no longer fulfilled diagnostic criteria for Fibromyalgia, and a quarter were judged to be in remission⁵⁹. Regular physical exercise showed the strongest effect.

A recent contribution⁶⁰ to the research on treated prognosis assessed the persistence of improvement after a 4 week multi-disciplinary outpatient course of treatment.

The significant improvements in severity of pain, interference with life activities, sense of control, emotional health (distress, depression and anxiety), and self-evaluated disability were maintained six months later.

Some symptoms are more resistant than others to Multidisciplinary Therapy, and how much an individual client will benefit can be incompletely predicted.

The researchers commented on the great variability in response between patients but were able to identify only some of the predictors of treated improvement in pain severity.

However, the therapy did not achieve even short-term gains in interpersonal relationships or general activities, and fatigue had already at 6 months returned to pretreatment levels.

The majority of patients diagnosed with FibroMyalgia Syndrome (FMS) are gainfully employed⁶¹.

Thrice weekly aerobic exercise has been further confirmed as reducing tender-point tenderness and possibly pain^45,62, but only in the short-term⁶².

For long-term benefit, various alternative therapies may materially improve prognosis for some clients - biofeedback, hypnotherapy, and Cognitive-Behavioural Treatment.

Acupuncture benefits some and worsens others^45,63,64. There is only weak evidence for the effect of chiropractic and massage therapies⁶⁴.

In asking the question of a physician, it should be noted that in this context the legal meaning of Disability,

want of physical or mental ability...by reason of intervening cause

is closer to the medical (World Health Organisation) definition of Impairment^**.

Medical expert witnesses are of least use to the court if they believe that either a) FMS is meaningless terminology, or b) the complaint of chronic widespread pain means disablement.

Although these extreme positions are seen all too frequently in defence and claimant experts respectively, they represent pre-judgments that belie a meaningful analysis of an individual claim.

How they address standard questions⁶¹ will reveal the prejudices and depth of analysis of medical expert witnesses.

Pre-injury records for 5 years or more should be reviewed for evidence for undiagnosed pre-existing FMS.

In only 10% of cases or less, review of 5 years’ pre-injury medical records will reveal no evidence of pre-existing symptoms of FMS or myofascial pain syndrome³³.

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.

If examination of the pre- and post- injury clinical records confirms de novo onset shortly after compensable injury, medical expert opinion favouring post-traumatic cause may prevail, even though there is presently little or no understanding of a pathophysiological mechanism.

There is no medical means of independently confirming the claim to be disabled because of chronic widespread pain.

There are no reliable clinical tests of disability attributed to pain⁶⁵.

The tender points of FMS are no more objective than the complaints of widespread pain, so a physician can add little to the "diagnosis" than indicate whether s/he believes the claimant.

The factors that determine the severity and impact of FMS are either inappropriate as criteria (education level, litigation status), or entirely subjective⁶⁶.

Many chronic widespread pain sufferers are not disabled, and severity of pain and associated symptoms does not determine disability status^39,61.

The condition is compatible with full-time employment⁶⁷.

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.

Medical experts on prognosis for both claimant and defence should be asked to address explicitly the impact of various pre-existing factors⁶⁸ on outcome:

In medical jargon, the differential diagnosis is usually between somatoform disorder^** and 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 coached⁶⁹ to simulate appropriate tenderness, and to avoid reacting to pressure at "control" tender points.

As well as rheumatologist and occupational physician, psychiatric assessment should be routine, and other specialties contribute as necessary - gastroenterology, neurology and general internal medicine.

Because these conditions lie in the expertise of psychiatrists and psychologists, those specialists have more to contribute than orthopedic surgeons, rheumatologists and physiatrists.

This is particularly true if major psychiatric disorders have been insufficiently considered.

Since in the legal arena the court claims the prerogative to determine veracity, a physician can otherwise give no more help than offer a personal opinion about the claimant’s sincerity, based on clinical experience.

Thus, the physician or psychologist merely expresses beliefs that are either congruent with or dissimilar to those of the claimant.

This takes the form of an expert report or testimony that is either advocative or descriptive⁷⁰, but provides no expert medical evidence of any substance.

Once significant or relevant physical disease and major psychiatric disorder has been excluded by careful medical and psychological assessment, further physical and mental examination is unhelpful in determining Disability⁷¹.

For most FMS patients there are significant discrepancies between self-report and observed functioning.

A promising approach⁷² has been to categorise FMS patients on psychosocial and behavioural responses to pain as Dysfunctional, Interpersonally Distressed, or Adaptive Copers for purposes of research into effective therapies.

In this study, only the Adaptive Copers showed a relationship between perceived disability and physical functioning, as measured by spinal mobility tests.

Although the other two groups showed comparable levels of physical functioning, they reported more pain and greater disability.

In contrast to patients suffering from other rheumatic conditions (ankylosing spondylitis and rheumatoid arthritis), FMS patients showed "striking discordance" between self-report and overt clinical surveillance⁷³.

Similarly, FMS patients report more pain than do patients with severe rheumatoid arthritis and other rheumatic disorders⁷⁴.

In the first detailed study⁷⁵ of psychiatric disability patients, almost 20% of the 500 had no significant or relevant physical disease or major psychiatric disorder.

They complained of general aches and pains and tiredness and were considered to have a very poor prognosis for return to work.

It appears that loss of functioning is caused by the belief that pain causes disability, rather than the severity of pain.

90% of FMS patients who desire to work are able to do so⁶⁷

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 phoning⁷⁶.

The Activities of Daily Living rating is the best instrument currently available for assessment of FMS disability³⁵.

About a fifth of FMS sufferers collect disability benefits at some stage of their illness³³.

Henry Ford’s proposition may apply: "If you believe you can do a thing, or if you believe you cannot, in either case you are probably right."