Musician’s cramp, and other so-called focal task-specific dystonias, are typically thought of as sporadic or occupational conditions. Now, researchers in the US and Germany have identified three families with these disorders, suggesting that the disorders may be inherited.
Dr. Christine Klein, a neurologist at the University of Lubeck, Germany, and her team identified three patients who played the piano or the guitar, and were diagnosed with musician’s dystonia — a potentially career-ending problem marked by muscle spasms in the hands or fingers that occur when they attempt to play their instruments.
Klein and colleagues subsequently learned that these three patients had family members who also suffered from focal task-specific dystonias.
According to the team, each “index” patient had two or three first-degree relatives with other forms of focal task-specific dystonia.
Six had writer’s cramp and one had handicraft dystonia manifested when threading a needle. Half of the subjects reported that increased practice seemed to trigger the dystonia.
“Our results suggest a genetic contribution to focal task-specific dystonia,” the team concludes. As more cases of familial focal task-specific dystonia are identified, genomic analysis may help identify the genes that are involved, they write.
SOURCE: Neurology August 22, 2006.