Benign fasciculation syndrome (BFS) is a disorder characterized by fasciculation (localized, uncoordinated twitching) of various voluntary muscles in the body. The twitching can occur in any voluntary muscle group but is most common in the eyelids, arms, legs, and feet. The twitching may be occasional or may go on nearly continuously. Any intentional movement of the involved muscle causes the fasciculations to cease immediately, but may restart once the muscle is at rest again. A fasciculation is a small, local involuntary muscle contraction (twitching) visible under the skin arising from the spontaneous discharge of a bundle of skeletal muscle fibres. ... A top-down view of skeletal muscle Muscle is a contractile form of tissue. ... An eyelid is a thin membrane of skin with the purpose of covering and protecting an eye. ... ARM may stand for: Most likely: ARM Ltd (originally Advanced RISC Machines) ARM architecture CPU design or one of its derivatives developed by ARM Ltd (originally called The Acorn RISC Machine) Adjustable rate mortgage Annotated Reference Manual (C++) Artificial rupture of membranes (see amniotic sac) the ISO 3166-1 3... Leg has multiple meanings: For the limbs of animals that support them above the ground: in the case of the legs of humans, see Human leg; in the case of the legs of horses, see Equine leg; in the case of the legs of crabs, lobsters, and their close relatives... Jump to: navigation, search This article needs to be cleaned up to conform to a higher standard of quality. ...

Common features

In addition to twitching, patients with BFS often experience pain, paraesthesia, generalized fatigue, exercise intolerance, globus sensation and/or muscle cramping. Paresthesia (paraesthesia in British) is a sensation of tingling, pricking, or numbness of the skin with no apparent physical cause, more generally known as the feeling of pins and needles. ... Jump to: navigation, search Fatigue is a state, following a period of mental or bodily activity, characterized by a lessened capacity for work and reduced efficiency of accomplishment, usually accompanied by a feeling of weariness, sleepiness, or irritability. ... Exercise Intolerance is a medical term used to describe a condition where the patient who is unable to do physical exercise at the level that would be expected of someone in his or her general physical condition, or who experiences unusually severe post-exercise pain, fatigue, or other negative effects. ...

Another common feature of the disorder is an dramatic increase in the patient's level of anxiety, especially health-related anxiety. It's not uncommon for the patient to fixate on ALS, vCJD, or some other similarly fatal disorder, refusing to believe the BFS diagnosis. Jump to: navigation, search Anxiety is a complex combination of the feeling of fear, apprehension and worry often accompanied by physical sensations such as palpitations, chest pain and/or shortness of breath. ... Motor Neurone Disease (MND) is a term used to cover a number of illnesses of the motor neurone. ... This article needs to be cleaned up to conform to a higher standard of quality. ...

Causes

Though twitching is sometimes a symptom of various serious diseases (spinal injury, muscular dystrophy, ALS, etc), it is much more often due to more benign causes (BFS, over-exertion, etc), and virtually everyone will experience some episodes of benign fasciculation during their lifetime. The spinal cord is a part of the vertebrate nervous system that is enclosed in and protected by the vertebral column (it passes through the spinal canal). ... The muscular dystrophies are a group of genetic and hereditary muscle diseases; characterized by progressive skeletal muscle weakness, defects in muscle proteins, and the death of muscle cells and tissue. ... Motor Neurone Disease (MND) is a term used to cover a number of illnesses of the motor neurone. ...

The precise cause of BFS is unknown, though very frequently anxiety is a major contributing factor. Another factor that seems to be common in many cases is a history of regular strenuous exercise. Attention deficit disorder or a related disorder may be a contributing factor, and people with essential tremor appear to have a greater than normal likelihood of developing BFS. In addition, there are likely other genetic and environmental factors that make the patient more susceptible to BFS. Jump to: navigation, search Anxiety is a complex combination of the feeling of fear, apprehension and worry often accompanied by physical sensations such as palpitations, chest pain and/or shortness of breath. ... DISCLAIMER Please remember that Wikipedia is offered for informational use only. ... Essential tremor is a neurological disorder characterized by shaking of hands (and sometimes other parts of the body including the head), evoked by intentional movements. ...

There are some intriguing similarities between BFS and chronic organophosphate poisoning, but these similarities have not been explored. It may be that chronically elevated levels of stress hormones in the body cause damage similar to the damage caused by organophosphates. An organophosphate (sometimes abbreviated OP) is the general name for any organic compound containing phosphorus. ...

Frequency

No rigorous study of the frequency of benign fasciculation syndrome has been done, but estimates are that it affects about one in every 200 adults to one degree or another. It's harder to estimate the frequency of those with relatively severe cases (nearly continuous fasciculations), but it's probably on the order of 10-20% of those who would be classified as having BFS.

Diagnosis

Diagnosis of BFS is a "diagnosis of exclusion" -- that is, other likely causes for the twitching (mostly other forms of neuropathy, like the one often associated with borreliosis) must be eliminated before BFS can be assumed. An important diagnostic tool here is the EMG, a test that measures the electrical signals generated by muscles. Since BFS appears to cause no actual nerve damage (at least as seen on the EMG), a completely normal EMG (or one where the only abnormality seen is fasciculations) largely eliminates more serious disorders and strongly suggests BFS. (For those with chronic ALS anxiety, it should be noted that one does not need to be actively twitching for the EMG results to be valid, nor is it necessary to test every limb.) Neuropathy is a disease of the peripheral or central nervous system. ... Borreliosis is a disease caused by the spirochete Borrelia Burgdorferi. ... Electromyography (EMG) is a medical technique for measuring muscle response to nervous stimulation. ...

The only commonly abnormal finding on examination by a neurologist is slightly brisk reflexes. Standard laboratory tests are unremarkable. // Definition A stereotyped (involuntary) motor response elicited by a defined stimulus. ...

Treatment

Some degree of control of the fasciculations may be achieved with the same drugs used to treat essential tremor -- beta-blockers and anti-seizure drugs. However, often the most effective approach to treatment is to treat any accompanying anxiety. Jump to: navigation, search A drug is any substance that can be used to modify a chemical process or processes in the body, for example to treat an illness, relieve a symptom, enhance a performance or ability, or to alter states of mind. ... Essential tremor is a neurological disorder characterized by shaking of hands (and sometimes other parts of the body including the head), evoked by intentional movements. ... Beta blockers or beta-adrenergic blocking agents are a class of drugs used to treat a variety of cardiovascular conditions and some other diseases. ...

No drugs, supplements, or other treatments have been found that completely control the symptoms.

Outlook

BFS is not life-threatening and generally not disabling, but it may be persistent enough to create some degree of disability, especially if cramps or pain are also present. In many cases, however, the accompanying anxiety is more disabling than the disease itself.

Outlook is mixed. The vast majority of cases clear up spontaneously in a few days or weeks (and in fact are never presented for diagnosis), but some may continue for years.

Note: Wikipedia does not give medical advice.