A 21-year-old man is referred for evaluation and treatment of abnormal movements. He was doing well until the age of 8 when he developed problems with supination of the left arm. He later developed tremor of the left hand, abnormal sustained movements of the left leg; in particular, inversion of the left foot, and back spasms such that he could not walk. His ability to walk improved somewhat, and he was able to ambulate after age 15. Currently he is attending college and doing well.
He writes and operates a computer keyboard exclusively with his right hand because of the rhythmic spasms on the left. His voice has been involved for the past 4 years. He has been tried on trihexyphenidyl, carbidopa/levodopa, carbamazepine, and diazepam with very modest improvement. His examination was remarkable for abnormal involuntary movements of his upper extremities, left more than right, consisting…
