Abstract

Dystonia is a syndrome of sustained muscle contraction, frequently causing twisting and repetitive movements, or abnormal postures. It may arise as an acute reaction to neuroleptic drugs or to levodopa treatment in Parkinson's disease, as a chronic generalised or as a focal disorder. The prevalence of diagnosed cases of dystonia is about 27 per 100,000,¹ of which over 90% are focal. Little has been written about it,² and many cases remain un- or misdiagnosed.