Study Status: Completed
Recruit Status: Completed
Study Type: Observational
Official Title: Nondystrophic Myotonias: Genotype-phenotype Correlation and Longitudinal Study
Brief Summary: Nondystrophic myotonias (NDM) are muscle disorders caused by genetic abnormalities in certain muscle cell membrane proteins. Individuals with NDM experience limited muscle relaxation, which causes pain, weakness, and impaired physical activity. The purpose of this study is to better characterize the clinical features and symptoms of NDM.