Page 506 - Basic _ Clinical Pharmacology ( PDFDrive )

28 Pharmacologic
C H A P T E R

Management of

Parkinsonism & Other

Movement Disorders

Michael J. Aminoff, MD, DSc, FRCP

C ASE STUD Y

A 76-year-old retired banker complains of a shuffling gait The patient is started on a dopamine agonist, and the
with occasional falls over the last year. He has developed dose is gradually built up to the therapeutic range. Was this
a stooped posture, drags his left leg when walking, and is a good choice of medications?
unsteady on turning. He remains independent in all activi- Six months later, the patient and his wife return for
ties of daily living, but he has become more forgetful and follow-up. It now becomes apparent that he is falling asleep
occasionally sees his long-deceased father in his bedroom. at inappropriate times, such as at the dinner table, and when
Examination reveals hypomimia, hypophonia, a slight rest awake, he spends much of the time in arranging and rear-
tremor of the right hand and chin, mild rigidity, and ranging the table cutlery or in picking at his clothes. To what
impaired rapid alternating movements in all limbs. Neuro- is his condition due, and how should it be managed? Would
logic and general examinations are otherwise normal. What you recommend surgical treatment?
is the likely diagnosis and prognosis?

Several types of abnormal movement are recognized. Tremor consists activity. In some instances, the proximal muscles of the limbs are
of a rhythmic oscillatory movement around a joint and is best char- most severely affected, and because the abnormal movements
acterized by its relation to activity. Tremor at rest is characteristic of are then particularly violent, the term ballismus has been used to
parkinsonism, when it is often associated with rigidity and an impair- describe them. Chorea may be hereditary or acquired and may
ment of voluntary activity. Tremor may occur during maintenance occur as a complication of a number of general medical disorders
of sustained posture (postural tremor) or during movement (inten- and of therapy with certain drugs.
tion tremor). A conspicuous postural tremor is the cardinal feature Abnormal movements may be slow and writhing in character
of benign essential or familial tremor. Intention tremor occurs in (athetosis) and, in some instances, are so sustained that they are
patients with a lesion of the brainstem or cerebellum, especially when more properly regarded as abnormal postures (dystonia). Atheto-
the superior cerebellar peduncle is involved; it may also occur as a sis or dystonia may occur with perinatal brain damage, with focal
manifestation of toxicity from alcohol or certain other drugs. or generalized cerebral lesions, as an acute complication of certain
Chorea consists of irregular, unpredictable, involuntary muscle drugs, as an accompaniment of diverse neurologic disorders, or as
jerks that occur in different parts of the body and impair voluntary an isolated inherited phenomenon of uncertain cause known as

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