Factors predicting improvement in motor disability in writer's cramp treated with botulinum toxin.
OBJECTIVE
To identify factors predicting improvement in motor disability in writer's cramp treated with botulinum toxin (BTX).


METHODS
47 patients with writer's cramp were treated with BTX and were evaluated by the same neurologists at initial referral, after each BTX injection, and when the effect of BTX was maximal at the time of the study. Patients and examiners simultaneously and independently rated the efficacy of BTX injections. Self assessment was a global clinical impression of the impact of treatment on writing quality, writing speed, writing errors, and legibility of handwriting; for objective assessment, the examiners used the Burke-Fahn-Marsden (BFM) scale.


RESULTS
On the BFM scale, there was a significant improvement (p<0.0001) in both severity and disability scores. Patients with a pronation/flexion pattern of dystonia showed the best and the most sustained improvement. Primary writing tremor was little improved. There was a correlation between the self assessment score and the Burke-Fahn-Marsden score. Benefit was maintained over time


CONCLUSIONS
These results have implications for the identification of patients most likely to benefit from BTX injections.
Djebbari
R
R
Department of Neurology, Hôpital Saint Antoine, Paris, France.
du Montcel
S T
ST
Sangla
S
S
Vidal
J S
JS
Gallouedec
G
G
Vidailhet
M
M
D000328:Adult; D000368:Aged; D018726:Anti-Dyskinesia Agents / Q000494:pharmacology* / Q000627:therapeutic use*; D001905:Botulinum Toxins / Q000494:pharmacology* / Q000627:therapeutic use*; D004421:Dystonia; D020821:Dystonic Disorders / Q000188:drug therapy* / Q000473:pathology; D005260:Female; D006225:Hand / Q000502:physiology; D006236:Handwriting; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D012720:Severity of Illness Index; D016896:Treatment Outcome
D018726:Anti-Dyskinesia Agents; D001905:Botulinum Toxins