Movement disorders lecture

6. Ballismus Dystonia Chorea Athetosis Movements become - Less violent / explosive / jerky - Smoother and more flowing - More sustained They differ from tics in that they cannot be suppressed by voluntary control Myoclonus

17. Athetosis is a slow continuous stream of slow, sinuous, writhing movements, typically of the hands and feet. Most commonly seen together with chorea in dyskinetic motor fluctuations in PD . Also in athetoid cerebral palsy where damage occurs in the basal ganglia. Related to excessive dopaminergic activity . In PD reducing dopaminergic drugs alleviates. If Athetosis becomes faster, it sometimes blends with chorea, ie choreoathetosis/ 'choreo-athetoid' movements. Can be thought of as an athetoid movement that “gets stuck” for a period of time; thus, a patient with choreoathetosis may perform an involuntary movement in which his hand and fingers are twisted behind his head. He may hold this position for a few moments before his hand moves back in front of his body. The part of the movement when the limb was held, unmoving, in an abnormal position would be considered a dystonia (may occur alone). Athetosis Athetosis Video: http://www.youtube.com/watch?v=J_wIDm1_ax4&feature=related

20. Extra material to read latter-Dystonia: Etiology Causes: Primary dystonia refers to the situation where dystonia is the only sign and there is no identifiable cause or structural abnormality in the central nervous system. Although the causes of dystonia are not fully known it is currently thought that the condition results from a malfunction in a part of the brain called the basal ganglia. The problem may mainly lie in an area of the basal ganglia called the globus pallidus. If this area of the brain is not functioning correctly then the control of another structure in the brain called the thalamus is affected. The thalamus controls the planning and execution of movement and sends nerves to muscles via the spinal cord. The end result is that muscle co-ordination is not regulated properly. The wrong muscles will contract on movement or all muscles will contract unnecessarily causing abnormal movement and posture. Secondary dystonia implies there is a clear cause, such as a change in the structure of the brain, an environmental cause, as part of an inherited or acquired neurological disease or due to drugs or toxins. Environmental causes include head trauma, stroke, a tumour, multiple sclerosis, infections in the brain, injury to the spinal cord, or after chemotherapy, drugs ( neuroleptics-Tardive dystonia ) or toxins that affect the basal ganglia, thalamus or brain stem. They may be associated with other hereditary neurological syndromes. Dystonia may be the first sign in a patient with Huntington's disease, and is secondary to many other neurological diseases including Parkinson's disease, Wilson's disease and Ataxia telangiectasia.