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Dystonia From Wikipedia
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A person with medication
induced dystonia.
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Signs and Symptoms
Symptoms vary according to the kind of dystonia involved. In most cases, dystonia tends to lead to abnormal posturing, in particular on movement. Many sufferers have continuous pain, cramping, and relentless muscle spasms due to involuntary muscle movements. Other motor symptoms are possible including lip smacking.
Early symptoms may include loss of precision muscle coordination (sometimes first manifested in declining penmanship, frequent small injuries to the hands, and dropped items), cramping pain with sustained use, and trembling. Significant muscle pain and cramping may result from very minor exertions like holding a book and turning pages. It may become difficult to find a comfortable position for arms and legs with even the minor exertions associated with holding arms crossed causing significant pain similar to restless leg syndrome. Affected persons may notice trembling in the diaphragm while breathing, or the need to place hands in pockets, under legs while sitting or under pillows while sleeping to keep them still and to reduce pain. Trembling in the jaw may be felt and heard while lying down, and the constant movement to avoid pain may result in the grinding and wearing down of teeth, or symptoms similar to TMD. The voice may crack frequently or become harsh, triggering frequent throat clearing. Swallowing can become difficult and accompanied by painful cramping.
Electrical sensors (EMG) inserted into affected muscle groups, while painful, can provide a definitive diagnosis by showing pulsating nerve signals being transmitted to the muscles even when they are at rest. The brain appears to signal portions of fibers within the affected muscle groups at a firing speed of about 10 Hz causing them to pulsate, tremble and contort. When called upon to perform an intentional activity, the muscles fatigue very quickly and some portions of the muscle groups do not respond (causing weakness) while other portions over-respond or become rigid (causing micro-tears under load). The symptoms worsen significantly with use, especially in the case of focal dystonia, and a "mirror effect" is often observed in other body parts: Use of the right hand may cause pain and cramping in that hand as well as in the other hand and legs that were not being used. Stress, anxiety, lack of sleep, sustained use and cold temperatures can worsen symptoms.
Direct symptoms may be accompanied by secondary effects of the continuous muscle and brain activity, including disturbed sleep patterns, exhaustion, mood swings, mental stress, difficulty concentrating, blurred vision, digestive problems, and short temper. People with dystonia may also become depressed and find great difficulty adapting their activities and livelihood to a progressing disability. Side-effects from treatment and medications can also present challenges in normal activities.
In some cases, symptoms may progress and then plateau for years, or stop progressing entirely. The progression may be delayed by treatment or adaptive lifestyle changes, while forced continued use may make symptoms progress more rapidly. In others, the symptoms may progress to total disability, making some of the more risky forms of treatment worth considering. In some cases with patients who already have dystonia, a subsequent tramatic injury or the effects of general anethesia during an unrelated surgery can cause the symptoms to progress rapidly.
An accurate diagnosis may be difficult because of the way the disorder manifests itself. Sufferers may be diagnosed as having similar and perhaps related disorders including Parkinson's disease, essential tremor, carpal tunnel syndrome, TMD, Tourette's syndrome, conversion disorder or other neuromuscular movement disorders. It has been found that the prevalence of dystonia is high in individuals with Huntington's disease, where the most common clinical presentations are internal shoulder rotation, sustained fist clenching, knee flexion, and foot inversion. Risk factors for increased dystonia in patients with Huntington's disease include long disease duration and use of antidopaminergic medication.
Causes
Primary dystonia is suspected to be caused by a pathology (disease) of the central nervous system, likely originating in those parts of the brain concerned with motor function, such as the basal ganglia, and the GABA (gamma-aminobutyric acid) producing Purkinje neurons. The precise cause of primary dystonia is unknown. In many cases it may involve some genetic predisposition towards the disorder combined with environmental conditions.
Secondary dystonia refers to dystonia brought on by some identified cause, usually involving brain damage, or by some unidentified cause such as chemical imbalance. Some cases of (particularly focal) dystonia are brought on after trauma, are induced by certain drugs (tardive dystonia), or may be the result of diseases of the nervous system such as Wilson's disease.
Environmental and task-related factors are suspected to trigger the development of focal dystonias because they appear disproportionately in individuals who perform high precision hand movements such as musicians, engineers, architects, and artists. Chlorpromazine can also cause dystonia, which can be often misjudged as a seizure. Neuroleptic drugs often cause dystonia, including oculogyric crisis.
Treatment
Reducing the types of movements that trigger or worsen dystonic symptoms provides some relief, as does reducing stress, getting plenty of rest, moderate exercise, and relaxation techniques. Various treatments focus on sedating brain functions or blocking nerve communications with the muscles via drugs, neuro-suppression, or denervation. All current treatments have negative side-effects and risks.
Physical Intervention
While research in the area of effectiveness of physical therapy intervention for dystonia remains weak, there is reason to believe that rehabilitation will benefit patients with dystonia. Physical therapy can be utilized to manage changes in balance, mobility and overall function that occur as a result of the disorder. A variety of treatment strategies can be employed to address the unique needs of each individual. Potential treatment interventions include splinting, therapeutic exercise, manual stretching, soft tissue and joint mobilization, postural training and bracing, neuromuscular electrical stimulation, constraint-induced movement therapy, activity and environmental modification, and gait training.
A patient with dystonia may have significant challenges in activities of daily living (ADL), an area especially suited for treatment by occupational therapy (OT). An occupational therapist (OT) may perform needed upper extremity splinting, provide movement inhibitory techniques, train fine motor coordination, provide an assistive device, or teach alternative methods of activity performance to achieve a patient's goals for bathing, dressing, toileting, and other valued activities.
Recent research has investigated further into the role of physiotherapy in the treatment of dystonia. A recent study showed that reducing psychological stress, in conjunction with exercise, is beneficial for reducing truncal dystonia in patients with Parkinson’s Disease. Another study emphasized progressive relaxation, isometric muscle endurance, dynamic strength, coordination, balance, and body perception, seeing significant improvements to patients’ quality of life after 4 weeks.
Some focal dystonias have been proven treatable through movement retraining in the Taubman approach, particularly in the case of musicians. However other focal dystonias may not respond and may even be made worse by this treatment.
Due to the rare and variable nature of dystonia, research investigating the effectiveness of these treatments is limited. There is no gold standard for physiotherapy rehabilitation. To date, focal cervical dystonia has received the most research attention; however, study designs are poorly controlled and limited to small sample sizes.
Medication
Different medications are tried in an effort to find a combination that is effective for a specific person. Not all people will respond well to the same medications. Medications that have had positive results in some include: diphenhydramine, benzatropine, anti-Parkinsons agents (such as trihexyphenidyl and bromocriptine), and muscle relaxants (such as diazepam).
Anticholinergics
Medications such as anticholinergics (benztropine), which act as inhibitors of the neurotransmitter acetylcholine, may provide some relief. In the case of an acute dystonic reaction, diphenhydramine is sometimes used (though this drug is well known as an antihistamine, in this context it is being used primarily for its anticholinergic role).
Baclofen
A baclofen pump has been used to treat patients of all ages exhibiting muscle spasticity along with dystonia. The pump delivers baclofen via a catheter to the thecal space surrounding the spinal cord. The pump itself is placed in the abdomen. It can be refilled periodically by access through the skin.
Botulin Toxin Injection
Botulinum toxin injections into affected muscles have proved quite successful in providing some relief for around 3–6 months, depending on the kind of dystonia. Botox injections have the advantage of ready availability (the same form is used for cosmetic surgery) and the effects are not permanent. There is a risk of temporary paralysis of the muscles being injected or the leaking of the toxin into adjacent muscle groups, causing weakness or paralysis in them. The injections have to be repeated, as the effects wear off and around 15% of recipients will develop immunity to the toxin. There is a Type A and a Type B toxin approved for treatment of dystonia; often, those that develop resistance to Type A may be able to use Type B.
Muscle Relaxants
Clonazepam, an anti-seizure medicine, is also sometimes prescribed. However, for most, their effects are limited and side-effects like mental confusion, sedation, mood swings, and short-term memory loss occur
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Parkinsonian Drugs
Dopamine agonists: One type of dystonia, dopamine-responsive dystonia, can be completely treated with regular doses of L-DOPA in a form such as Sinemet (carbidopa/levodopa). Although this does not remove the condition, it does alleviate the symptoms most of the time. (In contrast, dopamine antagonists can sometimes cause dystonia.)
Surgery
Surgery, such as the denervation of selected muscles, may also provide some relief; however, the destruction of nerves in the limbs or brain is not reversible and should be considered only in the most extreme cases. Recently, the procedure of deep brain stimulation (DBS) has proven successful in a number of cases of severe generalised dystonia. DBS as treatment for medication-refractory dystonia, on the other hand, may increase the risk of suicide in patients. However, reference data of patients without DBS therapy are lacking.
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Dystonia From Wikipedia
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