MOVEMENT DISORDERS

by Mary Ann Chapman

Parkinson’s disease is a neurological disorder characterized by tremor at rest, rigidity, and difficulty initiating movement. It is caused by the selective death of neurons in a the ventral midbrain, an area that is critical for movement. As of yet, no one knows precisely why these cells die.

Dystonia is a neurological disorder in which uncontrollable muscle contractions force certain parts of the body into abnormal, sometimes painful, movements or postures. The most common form of dystonia is cervical dystonia, sometimes called spasmodic torticollis, in contractions of the neck and/or shoulder muscles cause the head to twist or tilt.

Myoclonus is a rare neurological syndrome of sudden, brief, shock-like muscular contractions or inhibitions. Myoclonus may occur following the oxygen deprivation that occurs as a result of cardiac arrest but can also be caused by a number of other conditions.

Essential tremor denotes a condition of involuntary trembling, usually of the hands. This tremor is distinguished from parkinsonian tremor by its fine, rapid nature. This condition is usually hereditary and may progress to involve additional parts of the body. In some cases, however, the tremor remains largely confined to a single body region.

Spasticity is a condition of increased muscle tone and exaggerated deep tendon reflexes. The condition often leads to postural deformity and can interfere with a person’s ability to carry out the activities associated with daily living. Spasticity can occur following damage to the central nervous system resulting from a stroke, traumatic brain injury, spinal cord injury, multiple sclerosis, cerebral palsy, or other conditions.