Video-supervised Motor and Awareness Training in Writer's Cramp

The Canadian Occupational Performance Measure will serve as the primary outcome measure. Patients grade their self-perceived performance and satisfaction of writing related occupations in daily life in respect to the goals they had identified and prioritized. The COPM ist patient centered end reflects the real life of the participants.

The kinematic handwriting analysis will be performed on a pressure sensitive digitizing tablet, that is connected to a laptop to measure movements of the pencil during writing. Regularity of writing will be calculated from this data. All subjects will write a standardized sentence and draw superimposed circles to characterize handwriting movements.

The video based Writer's Cramp Rating Scale will serve as a secondary outcome parameter. The videos are rated by a blinded movement disorder specialist according to flexion / extension of arm / wrist / fingers during writing.

During this task participants will be instructed to a) write a sentence using an MR-compatible tablet and b) imagine writing in randomized order. The task is performed during a fMRI measurement. With the imaginary task artefacts are avoided and activation during movement planning will be investigated in the fMRI.

The purpose of the semi-structured qualitative interviews about the training procedures is to optimize the training and to differentiate between responders and non-responders. The interviews will be will be transcribed word-for-word and analyzed using the qualitative content analysis.

The Arm Dystonia Disability Scale will be applied to assess how dystonia interferes with manual activities during daily life (writing, buttoning, hygiene, eating, job or household).

The Serial Reaction Time Task is a standardized method to investigate motor sequence learning and to induce cerebellar activation. We expect that abnormal cerebellar activity in patients compared to controls normalizes after training.