The Effect of Two Weeks of Transcranial Direct Current Stimulation on Neurorehabilitation of Musician’s Dystonia: A Follow Up

Special Article - Neurorehabilitation

Austin J Clin Neurol 2017; 4(2): 1106.

The Effect of Two Weeks of Transcranial Direct Current Stimulation on Neurorehabilitation of Musician’s Dystonia: A Follow Up

Rosset-Llobet J1,2* and Fàbregas-Molas S1,2

¹Institut de Fisiologia i Medicina de l’Art - Terrassa, Spain

²Fundació Ciència i Art, Spain

*Corresponding author: Rosset-Llobet J, Institut de Fisiologia i Medicina de l’Art-Terrassa, Ctra de Montcada 668, 08227 Terrassa (Barcelona), Spain

Received: April 05, 2017; Accepted: May 15, 2017; Published: May 23, 2017


Background: We previously conducted a study where we combined a neurorehabilitation protocol for right hand task-specific focal dystonia with biparietal transcranial direct current stimulation (tDCS) with left-sided cathode. After two weeks, this protocol showed a significantly greater reduction of symptoms compared with the reduction observed in those musicians receiving neurorehabilitation combined with sham tDCS. After that, patients continued with the neurorehabilitation protocol without tDCS. As the whole rehabilitation process for these patients lasts more than a year, we wonder if this short period of tDCS stimulation is strong enough to change the outcome of the rehabilitation process in these patients.

Objective: Analyse whether, at the end of treatment, there is a higher proportion of cured musicians in the group of patients who received concomitant real tDCS during the first two weeks of the neurorehabilitation protocol, and whether this group recovered in a shorter period of time than those who received concomitant sham tDCS.

Method: Twenty-six musicians with right hand primary focal dystonia where followed during their neurorehabilitation process based on Sensory Motor Retuning therapy. During the first two weeks they also received either real or sham tDCS (cathode over left and anode over right parietal region) for the first 30 minutes of each 1-hour daily therapy session (total 10 sessions). After that, all patients continued with their daily rehabilitation sessions until complete recovery or until abandoning therapy due to lack of results. During the whole process, the therapist and the patients were blind to the initial tDCS condition. We compared proportions of cured patients and the time necessary to complete recovery in both groups.

Results: Of the 13 musicians who received active tDCS, 8 were cured of their dystonia whereas among the 13 who received sham tDCS, 9 were cured. This proportion is not statistically different (F=0.17; p=0.5; Risk Test=1.41). The patients of the active group who were cured took an average of 16.84±3.42 months to do so whereas those that received sham tDCS took an average of 17.38±4.26 months. The time taken was not statistically different between the two groups (U=33.5; p=0.82).

Conclusion: Although two weeks of bi-parietal tDCS can increase the effectiveness of rehabilitation in patients with task-specific focal hand dystonia, this short period of stimulation -mostly if we compare it with the average 17 months of duration of the entire process- do not produce any significant effect on the final therapy outcome. Future studies will be necessary to evaluate whether lengthening the stimulation period or maintaining it throughout the whole rehabilitation process can produce beneficial effects on the outcome of these patients.

Keywords: Task-specific dystonia; Neurorehabilitation; Transcranial direct current stimulation; Musician; Sensory motor retuning


TSFHD: Task-Specific Focal Hand Dystonia; SMR: Sensory Motor Retuning; tDCS: transcranial Direct Current Stimulation; DES: Dystonia Evaluation Scale


Musician’s dystonia, one of the more frequent forms of taskspecific focal hand dystonia (TSFHD), is a relatively frequent condition that is estimated to affect more than 1% of professional musicians. It is characterised by loss of coordination or motor control that affects specific tasks on the instrument. It can affect all kind of musicians and may severely compromise the career of the professional it affects. Although botulin toxin injections and neuro modulators have been used to reduce the symptoms, only neurorehabilitative techniques, such as Sensory Motor Retuning (SMR), have been able to completely revert the symptoms at the same time that it reprograms the brain [1]. However, these techniques require extremely long treatment times, rarely less than one year [2].

As Transcranial Direct Current Stimulation (tDCS) enables modulating cortical excitability and improves the efficacy of some neurorehabilitation processes [3-6] we hypothesised that this technique could also improve the efficacy of neurorehabilitation of musicians with dystonia, either by increasing the efficacy or accelerating the process. This is why we designed a study where we combined two weeks of SMR with real or sham tDCS. Using a dystonia evaluation scale, a structured test that included 15 items and that has been showed high correlation with objective measurements [1], we observed that both groups significantly reduced dystonia symptoms after these two weeks and the improvement was significantly greater in the SMR plus real tDCS stimulation group [7]. But the neurorehabilitation process in TSFHD patients requires months of retraining and there is still not enough scientific information about the effects and safety of tDCS if applied during more than two weeks. This is why these patients continued the retraining without tDCS stimulation until complete recovery or abandon of the therapy. In this second part of the study, we wanted to determine whether the enhancing effects of tDCS observed over the two weeks had any long term effect on these patients.

Material and Methods


This is the long-term follow up part of a previously published study [7]. The design was a parallel double-blind, randomized blocked clinical trial. Participants were randomly assigned to one of the two treatment groups according to a computer-generated, blocked (15 patients in each group) randomization process. As previous studies showed no influence of dystonia severity, age, sex, dystonia onset, instrument or other clinical or professional variables on the SMR treatment outcome, there was no balanced allocation for this aspect [8]. The patient allocation data were only accessible by the main researcher (JR-L) and locked in a password protected computer document. He was also responsible for setting the tDCS stimulator for each patient so participants, therapists, and data collectors did not know if the patient was treated with real or sham tDCS.

The study took place at the Institut de Fisiologia i Medicina de l’Art, Terrassa (Barcelona), a medical centre specialised in the diagnosis and treatment of performing artists and referral centre for TSFHD.


Thirty consecutive pianists and guitarists seeking treatment for their TSFHD affecting the right hand, between January and December 2012 were included. Of them, only twenty-six completed the previous study (Figure 1). The mean age was 35.00±8.11 years; 6 were women, and 20 men; 10 played the piano and 16 the guitar. All participants where first examined by the main author (JR-L), a physician with more than 25 years of experience in TSFHD to ensure the diagnosis and rule out other mental or physical problems. Exclusion criteria were bilateral TSFHD, secondary causes of TSFHD, generalized dystonia, other concurrent uncontrolled illnesses, pharmacological treatment of any kind, pregnancy, epilepsy, substance abuse, metal devices in the head, left handedness (assessed by the Edinburgh Handedness Inventory), and botulinum toxin injection within the last 15 weeks. All patients gave their informed consent to participate in the study, which was approved by the Institutional Research Ethics Committee, and conducted in accordance with the Declaration of Helsinki. This study was reviewed and approved by our IRB with identifier FCA- 11/1.

Citation: Rosset-Llobet J and Fàbregas-Molas S. The Effect of Two Weeks of Transcranial Direct Current Stimulation on Neurorehabilitation of Musician’s Dystonia: A Follow Up. Austin J Clin Neurol 2017; 4(2): 1106. ISSN:2381-9154