[Treatment of writer's cramp with botulinum toxin].

Writer's cramp is a focal dystonia that is resistant to most treatment regimens. This article describes two patients with writer's cramp who were successfully treated with botulinum toxin injections into the forearm muscles. Transient weakness due to the effect of botulinum toxin was registered in the injected muscles. No other side effects were observed. The beneficial effect of a single injection lasted from three to four months and could be reproduced by repeated injections over a three year follow-up period. We conclude that botulinum toxin injections may provide safe and effective treatment in selected patients with writer's cramp.