A 76-year-old retired banker complains of a shuffling gait with occasional falls over the last year. He has developed a stooped posture, drags his left leg when walking, and is unsteady on turning. He remains independent in all activities of daily living, but he has become more forgetful and occasionally sees his long-deceased father in his bedroom. Examination reveals hypomimia, hypophonia, a slight rest tremor of the right hand and chin, mild rigidity, and impaired rapid alternating movements in all limbs. Neurologic and general examinations are otherwise normal. What is the likely diagnosis and prognosis?
The patient is started on a dopamine agonist, and the dose is gradually built up to the therapeutic range. Was this a good choice of medications?
Six months later, the patient and his wife return for follow-up. It now becomes apparent that he is falling asleep at inappropriate times, such as at the dinner table, and when awake, he spends much of the time in arranging and rearranging the table cutlery or in picking at his clothes. To what is his condition due, and how should it be managed? Would you recommend surgical treatment?
Several types of abnormal movement are recognized. Tremor consists of a rhythmic oscillatory movement around a joint and is best characterized by its relation to activity. Tremor at rest is characteristic of parkinsonism, when it is often associated with rigidity and an impairment of voluntary activity. Tremor may occur during maintenance of sustained posture (postural tremor) or during movement (intention tremor). A conspicuous postural tremor is the cardinal feature of benign essential or familial tremor. Intention tremor occurs in patients with a lesion of the brainstem or cerebellum, especially when the superior cerebellar peduncle is involved; it may also occur as a manifestation of toxicity from alcohol or certain other drugs.
Chorea consists of irregular, unpredictable, involuntary muscle jerks that occur in different parts of the body and impair voluntary activity. In some instances, the proximal muscles of the limbs are most severely affected, and because the abnormal movements are then particularly violent, the term ballismus has been used to describe them. Chorea may be hereditary or acquired and may occur as a complication of a number of general medical disorders and of therapy with certain drugs.
Abnormal movements may be slow and writhing in character (athetosis) and, in some instances, are so sustained that they are more properly regarded as abnormal postures (dystonia). Athetosis or dystonia may occur with perinatal brain damage, with focal or generalized cerebral lesions, as an acute complication of certain drugs, as an accompaniment of diverse neurologic disorders, or as an isolated inherited phenomenon of uncertain cause known as isolated generalized torsion dystonia or dystonia musculorum deformans. Various genetic loci have been reported depending on the age of onset, mode of inheritance, and response to dopaminergic therapy. The physiologic basis is uncertain, and treatment is ...