Prospective clinical study of writer's cramp

Sixty-five consecutive patients with writer's cramp were studied prospectiv ely to evaluate clinical and demographic features, the number of writing ho urs per day at dystonia onset, and the existence of trigger events. Assessm ent of writing and drawing was done on a standardized test using categorica l scales. The importance of subjective handicap and pain, of postural and a ction tremor, the abnormal features of hand grip and the occurrence of mirr or dystonia (dystonia occurring in the dominant hand when writing with the other hand) were studied. Thirty-two patients had simple writer's cramp, wh ereas the others had complex writer's cramp with several activities other t han writing involved. No significant differences were seen in age of onset, legibility, pain, and handicap in these two groups. Seven patients had a. family history of focal dystonia and six of them had a complex form of writ er's cramp. Mirror dystonia was seen in 29 patients and in some it appeared useful to distinguish dystonic movements from secondary compensatory strat egies. (C) 2001 Movement Disorder Society.