Movement involves a complex interaction between the central nervous system (brain and spinal cord), nerves and muscles. If any of these become damaged or malfunction, the result could be a movement disorder. For example:
- Damage to the parts of the brain that control voluntary (intended) movement or the connections between the brain and spinal cord: Weakness or paralysis of the muscles involved in voluntary movements and exaggerated reflexes
- Damage to the basal ganglia (collections of nerve cells located at the base of the cerebrum, deep within the brain): Involuntary (unintended) or decreased movements, but not weakness or changes in reflexes
- Damage to the cerebellum: Loss of coordination
The basal ganglia help smooth out muscle movements. The cerebellum coordinates the body’s movements, helps the limbs move smoothly and accurately, and helps maintain balance.
Some movement disorders, such as hiccups, are temporary, usually causing little inconvenience. Others, such as Parkinson disease, are serious and progressive, impairing the ability to speak, use the hands, walk, and maintain balance when standing.
Types of movement disorders include:
Persons who are diagnosed with ataxia experience a failure of muscle control in their arms and legs which may result in a lack of balance, coordination, and possibly a disturbance in gait. Ataxia may affect the fingers, hands, arms, legs, body, speech, and even eye movements.
Dystonia is a neurological condition with a very broad range of manifestations. The basic underlying problem involves over-activity of the main muscles needed for a movement, extra activation of other muscles that are not needed for the movement, and simultaneous activation of muscles that work against each other.
Essential tremor (ET) is the most common movement disorder. It is a progressive, often inherited disorder that usually begins in later adulthood. Patients with ET typically experience tremors when the arms are held up and when the hands are being used for activities like eating, drinking or writing.
Parkinson's disease (PD or, simply, Parkinson's) is the most common form of parkinsonism, a group of motor system disorders. It is a slowly progressing, degenerative disease which results from the loss of dopamine-producing brain cells.
Atypical Parkinsonisms are disorders that can produce signs and symptoms similar to those of Parkinson's disease, but do not respond to typical Parkinson's disease medications such as levodopa. Treatments Depending on the type and severity of the movement disorder, treatments can range from botulinum neurotoxin (like that used to reduce facial wrinkles), medications, physical therapy and deep brain stimulation.
