Fibromyalgia is a multidimensional, non-articular, chronic pain disorder with complex symptomatology and poor treatment outcomes. Fibromyalgia is characterised by widespread musculoskeletal pain for longer than three months and bilateral sites of amplified tenderness. It is typically associated with increased tenderness, persistent fatigue, anxiety, depression, non-refreshing sleep, stiffness, cognitive disturbances etc. it is reported to be more common in women and persons with rheumatic conditions. The most common age group affected is between 45-60 years but it can occur in any age. The etiology and pathophysiology of fibromyalgia remain unclear. Current hypothesis center on atypical sensory processing in the central nervous system and dysfunction of skeletal muscle nociception and the hypothalamic-pituitary –adrenal axis. The onset of fibromyalgia can be sudden or gradual, traumatic or non-traumatic. The trigger factors involved can be mechanical or physical trauma or injury psychosocial stressors related to genetic factors providing a potential inherited risk factor. Current treatments for fibromyalgia include medical, self-management and alternative interventions. Treatment remains inadequate to reliably resolve persistent symptoms and improve functional limitations and quality of life in most patients. One reason for unsatisfactory outcomes may be the absence of an evidence based standard of care.
Fibromyalgia is a distinctive condition which can be diagnosed with clinical precision and there is growing recognition of fibromyalgia as a distinct subgroup of chronic pain sufferers. The criterion for diagnosis is based on American College of Rheumatology definition produced in 1990. During assessment it is important to take careful history and record the individual pain experience and description. Patient of fibromyalgia do not look ill and appear clinically weak. Blood tests, scans, X-rays give negative results.
Before concluding fibromyalgia other pathological conditions that can cause chronic pain, inflammation and fatigue need to be excluded, which could include:
- Thyroid dysfunction
- Joints inflammation
- Systemic malaise with weight loss
History of widespread pain
Pain is considered widespread when all of the following are present:
- Pain in the left side of the body
- Pain in the right side of the body
- Pain above the waist
In addition, axial skeletal pain (cervical spine or anterior chest or thoracic spine or low back) must be present. In this definition shoulder and buttock pain is considered as pain for each involved side. “Low back” pain is considered lower segment pain.
Pain in 11 of 18 tender points sites on digital palpation. Pain, on digital palpation, must be present in at least 11 of the following 18 tender point sites.
THE AMERICAN COLLEGE OF RHEUMATOLOGY 1990 CRITERIA FOR CLASSIFICATION OF FIBROMYALGIA
- Digital palpation should be performed with an approximate force of 4 kg, as measured with a dolorimeter. For a tender point to be considered positive the subject must state that the palpation was painful. “Tender” is not be considered “painful”.
- For classification purposes, patients will be said to have fibromyalgia if both criteria are satisfied. Widespread pain must have been present for at least 3 months. The presence of a second clinical disorder does not exclude the diagnosis of fibromyalgia.
Fibromyalgia is commonly assessed by the visual analog scale (VAS). The typical VAS scale is 100mm in length and anchored by the extremes of the characteristic being assessed; that is, absence of pain or most pain ever experienced. The VAS scale is also used to assess other common symptoms, including general fatigue, tiredness upon awakening, sleep and mood.
Other methods for assessing are:
- Paper diary
- Electronic diary
- Symptom specific questionnaires-short-form McGill Pain Questionnaire
- Beck Depression Inventory
- Beck Anxiety Inventory
Levels of physical and emotional function are important outcomes for chronic-pain-intervention studies and are increasingly used in fibromyalgia research. The Fibromyalgia Impact Questionnaire (FIQ) the most commonly used measure of function in patient population, is a 10-item, reliable, responsive instrument that assesses physical function, common fibromyalgia symptoms and general well-being over the previous 7 days. A change in the total score of 20% or greater has been suggested to be clinically significant.
Pathology of fibromyalgia is unknown at present but previous studies and research suggests increasing evidence of the following mechanisms:
Pain amplification: Studies and research indicates sensitisation of peripheral and central nervous system. There is threefold increase in substance P during measurement of neurotransmitter levels in cerebrospinal fluid (CSF) and fourfold increase in nerve growth factor. These with continuous peripheral pain stimulation augmenting the levels of glutamate, activate N-methyl-D-aspartate (NMDA) receptors leading to central sensitisation. Diminished levels of serotonin and nor-adrenaline (Inhibition pathway) also cause pain amplification.
Sleep abnormalities: Symptoms of fibromyalgia such as muscular pain, increased tenderness and fatigue can be induced by disturbing sleep patterns in healthy individuals. Intrusion of alpha waves in stage 4 delta sleep has been demonstrated in patients of fibromyalgia using electroencephalogram. There are bidirectional link between lack of sleep and symptoms of pain and fatigue as well as higher comorbidity of sleep apnoea ad restless leg syndrome in patients of fibromyalgia.
Dysautonomia: Research indicates that dysautonomia in patients suffering from fibromyalgia have increased sympathetic and decreased parasympathetic activity in autonomic nervous system. Dysautonomia may cause symptoms of morning stiffness, intestinal irritability, sleep disturbances, depression and generalized anxiety.
Hormone disruption: Studies show that disruption in hypothalamus-pituitary-adrenal axis with elevated levels of (CRH) cortical releasing hormone and adrenal cortical stimulating hormone in conjugation with low 24 hour urinary cortisol levels. Elevated levels of CRH lead to increased levels of somatostatin which operates to reduce levels of thyroid hormone, growth hormone and oestrogen and increasing prolactin. These entire imbalances are noticed in fibromyalgia.
Investigators continue to search for ways to apply currently available medications and other medical interventions to improve the clinical outcomes of fibromyalgia patients. Drugs remain the primary treatment option for fibromyalgia and the tricyclic antidepressants and their analogs are the drugs of choice.
The newest direction of pharmacotherapy is in the area of dual reuptake inhibitors and an antiepileptic. Approved by the US Food and Drug Administration for depression, duloxetine and milnacipran are serotonin and norepinephrine- reuptake inhibitors that have shown encouraging results in preliminary studies with fibromyalgia. However many patients find these medications either insufficient to control their symptoms and difficult to tolerate their adverse effects. Thus all the medication should be reviewed at regular intervals to monitor their efficacy.
Drugs used are:
Tricyclic antidepressants (TCAs): Amytryptylline- low doses are commonly used to reduce pain and fatigue.
Selective serotonin reuptake inhibitors (SSRIs): Fluoxetine- can improve the symptoms of fatigue, depressionand pain. Insomnia and restlessness can be caused therefore morning administration is advised.
Serotonin-noradrenaline reuptake inhibitors (SNRIs): duloxetine, milnacipran- reduce pain, improve physical function and quality of life.
Anticonvulsants: Pregabalin, gabapentin also reduce pain, improve sleep quality.
Dopamine agonist: pramipexole.
Muscle relaxants: baclofen, tizanidine is helpful if muscle twitching or cramps accompany the pain.
Tramadol, a centrally acting analgesic also helps in reducing pain through endorphins
Efficacy evidence of NSAIDs is lacking and of steroids is contradictory.
Body conditioning and exercise management
Fibromyalgia can affect individuals in many ways resulting in reduced social, emotional and physical functioning. Muscle weakness and stiffness, reduced fitness and activity levels can lead to cycle of deconditioning
The number of studies evaluating various forms of aerobic and strength training exercise in people with fibromyalgia has grown exponentially. In the past year, studies evaluating pool and resistance exercise reported positive outcomes. Recent research has shown that exercise can activate the parts of brain which suppresses pain.
In order to gradually increase their exercise and activity levels over a time, a tolerance and baseline approach is most useful to encourage consistency and adherence.
EXAMPLE OF A TOTOLERANCE AND BASELINE APPROACH
|Exercise||Day1 Tolerance||Day 2 Baseline||Day 3||Day 4||Day 5||Day 6||Day 7||Exercise strategy|
EOD means to add one repetition every other day
ED means to add one repetition every day
Key principles of exercise management
- Encourage the individual to select type of exercise that their interests.
- Exercise can reduce pain.
- Encourage the individual to be patient and continue with a flexible routine they can incorporate in their lifestyle.
- Exercise is means to increase the activity levels.
Deconditioning is one of the barriers to continue with activity as muscle and joints fail to be used in the normal way due to pain. Equipment and aids appears to be tempting but it is helpful to force your own body to do daily activity.
If changes in activity management are to be maintained and sustained in the home, socially and work, communication with family and friends will be important. Engaging them in trying new process and then reporting back the benefits or costs will be part of helping to decide on strategies they feel able to make a part of their life.
Tender points vs Trigger points
Tender points are the selective areas of tenderness used for the diagnosis of fibromyalgia. These usually occur in pairs so they are distributes equally to both sides of body. They produce pain when pressed upon but do not refer pain to other part of body.
Trigger points are not specific to fibromyalgia but often magnified by pain amplification. These are responsible for myofascical pain and occur in acute and chronic state.