 About 30,000 people in the United States are affected.Myotonic dystrophy was first described by a German physician, Hans Gustav Wilhelm Steinert, who first published a series of 6 cases of the condition in 1909.Isolated case reports of myotonia had been published previously, including reports by Frederick Eustace Batten and Hans Curschmann, and Type 1 myotonic dystrophy is therefore sometimes known as Curschmann-Batten-Steinert syndrome.