Hahn, ChrisSalajegheh, Mohammad2016-06-142016Hahn, Chris, and Mohammad Kian Salajegheh. 2016. “Myotonic disorders: A review article.” Iranian Journal of Neurology 15 (1): 46-53.2008-384Xhttp://nrs.harvard.edu/urn-3:HUL.InstRepos:27320360The myotonic disorders are a heterogeneous group of genetically determined diseases that are unified by the presence of myotonia, which is defined as failure of muscle relaxation after activation. The presentation of these disorders can range from asymptomatic electrical myotonia, as seen in some forms of myotonia congenita (MC), to severe disability with muscle weakness, cardiac conduction defects, and other systemic features as in myotonic dystrophy type I (DM1). In this review, we describe the clinical features and pathophysiology of the different myotonic disorders, their laboratory and electrophysiologic findings and briefly review the currently available treatments.en-USMyotoniaMyotonic DystrophyMyotonia CongenitaParalysis Periodica ParamyotoniaHyperkalemic Periodic ParalysisJournal Article2016-06-14