A combination of constraint-induced therapy and motor control retraining in the treatment of focal hand dystonia in musicians

Abstract

UNLABELLED: Focal hand dystonia (FHD) in musicians is a painless task-specific motor disorder characterized by an involuntary loss of control of individual finger movements. The aim of this study was to investigate the effects of an innovative behavioural therapy intervention, aimed at normalising movement patterns, in musicians affected by FHD. METHODS: Eight musicians volunteered to take part in this retraining protocol. Intensive constraint-induced therapy and motor control retraining at slow speed were the interventions. Video recordings of the subjects playing two pieces were used for data analysis. The Frequency of Abnormal Movements scale (FAM), the change in metronome speed achieved during motor control retraining, and two ordinal dystonia evaluation scales were chosen as outcome measures. It was hypothesised that there would be significant differences in the FAM scores and metronome speeds over a 12-month period. RESULTS: For the main outcome measure, the FAM scale scores, the two-factor repeated measures ANOVA revealed a very significant decrease in the number of abnormal movements per second of instrumental playing over the 12-month period (F = 6.32, df = 7, p < 0.001). Tukey's post-hoc tests carried out for the FAM scores revealed that significant changes occurred after 8 months of therapy. DISCUSSION: These results suggest that a combination of constraint-induced therapy and specific motor control retraining may be a successful strategy for the treatment of musicians' FHD. Furthermore, the results suggest that retraining strategies may need to be carried out for at least 8 months before statistically significant changes are noted.