Dystonia is a Movement Disorder. It is characterized by involuntary abnormal muscle contractions that lead to abnormal torsional movements or position of the trunk, the neck and/or the extremities, with or without a tremor. Often there is pain as well. Uncontrollable repetitive movements and the inability to maintain a normal posture can be the result of this type of muscle spasms.
The most common form of dystonia is focal or segmental dystonia. Generalized dystonia is usually of genetic etiology. Dystonia can also appear as a complication of stroke. The symptoms may be very mild at first, but gradually they progress and become more frequent and intense. Muscle spasms of this type include the torticollis (where there is head tilt or turn to one side), blepharospasm (where there is excessive closing of the eyelids) and dystonia of the larynx that affects the muscles that control speech.
Dystonia can be caused by imbalance of chemical neurotransmitters in the parts of the brain called basal ganglia. These neurochemicals (serotonin, dopamine, acetylcholine and GABA) are required to properly send messages between brain cells.
Treatment may include medication to restore neurotransmitter levels to normal.
Mild dystonia is treated very effectively by injecting botulinum toxin (Botox, Dysport), intramuscularly. Botulinum toxin reduces muscle contraction, affects the feeling of muscle tension due to its influence on muscle spindles and most of the time has very good results, in cases of focal or segmental dystonia, without systemic side effects. The infusion, depending on the case, is performed under electromyographic and / or ultrasound guidance, in the office, with a thin syringe. The results begin to appear about 3-7 days after the infusion, peak in 2-3 weeks and last 3-4 months.
Treatment resistant dystonia is treated with deep brain stimulation (DBS) with good results. A Movement Disorders Specialist can identify appropriate candidates and provide counselling and prognosis.
