Idiopathic foot dystonia treated with intramuscular phenol injection.

We describe a patient who developed involuntary, painless, dystonic contraction of the left foot on walking. The patient had been treated with botulinum toxin A without benefit. Examination showed that walking brought on a spasmodic twisting of the left foot, with extension and eversion of the ankle. The patient underwent an intramuscular phenol injection, which abolished the foot dystonia. This case suggests that intramuscular phenol treatment may be an alternative for patients where botulinum toxin was unable to relieve the dystonias.