Many people with Parkinson's disease (PD) experience dystonia -- prolonged muscle contractions that can cause abnormal movements and postures -- as a symptom of disease or a complication of treatment. Dystonia can be a disease by itself, too, and one population it can affect is musicians.
"Musician's dystonia is relatively rare, but the prevalence is much higher than other forms of dystonia among the general population. The background of extensive training brings it out," explains Christine Kim, MD, a movement disorder specialist and instructor of Neurology at Yale School of Medicine.
This spring, Dr. Kim was among the first class of fellows to graduate from the Edmond J. Safra Fellowship in Movement Disorders, a program supported by The Michael J. Fox Foundation to increase the number of clinician-researchers specially trained to treat movement disorders worldwide.
Her research focuses on task-specific dystonia where involuntary muscle contractions affect one body part (e.g., writer's cramp). For a person with task-specific dystonia, symptoms only occur when performing a particular task, such as playing a musical instrument. As a professional violinist herself, Dr. Kim has a particular interest in this type of dystonia, which affects up to two percent of professional musicians and can be career-ending. As a musician learns specific movements, these tasks are stored in the brain as sensory motor programs. In musician's dystonia, the sensory motor programs associated with playing the instrument are somehow disrupted.
Therapeutic options are largely the same as dystonia in Parkinson's and may include botulinum toxin (Botox) injections and/or oral medications. For musicians, the available treatments can present certain limitations.
"Dystonia medications tend to have side effects including impaired concentration and confusion. For musicians trying to play in a high-pressure situation, these side effects are difficult to deal with," says Dr. Kim.
Research is ongoing, and Dr. Kim is testing retraining therapy, combining physical therapy and behavioral intervention so patients can gradually relearn the movement and "rewire the brain." Using brain imaging, she hopes to quantify the changes in the brain that occur during this retraining process to better understand the altered pathways and ultimately, determine how to prevent it.
"The answer to a treatment for dystonia or Parkinson's isn't going to be one magic solution. It's going to be the application of multiple different components," she says.