The characteristic feature of all movement disorders is an abnormality of the form and velocity of movements of the body. The term ‘movement disorder’ has become synonymous with basal ganglia disease and extrapyramidal features. Although many movement disorders do arise from pathology within the basal ganglia, disorders such as myoclonus may also arise from other structures. Abnormality of movement may be the only manifestation of a disease process, or may be part of a more widespread neurological disorder. It is important not to divorce the disorder of movement from general medical problems, since these may be directly or indirectly related (for example, chorea in systemic lupus erythematosus; DIP caused by amiodarone). Basal ganglia disease is commonly associated with neuropsychiatric symptoms and these may have a greater impact upon the patient and their family than the movement disorder itself.
An essential first step in the approach to the patient with a movement disorder is to correctly determine the phenomenology of the problem (for example, is the dominant problem chorea or dystonia?). Once this first step has been made, appropriately targeted investigations may then be required to determine the diagnosis. Thereafter, consideration is given to treatment, based upon clinical and social factors, as well as patient preference. This overview will describe a practical approach to the patient with a movement disorder. It will also briefly consider some broad principles in the investigation and management of such cases.
