Myotonia is a rare condition in which the muscles are unable to relax after they contract. This can affect muscles throughout the body and is caused by changes in the genetics of the individual ...

Background A 56-year-old woman was referred to a neurogenetic clinic with a history of stiffness and transient weakness. A previous needle electromyogram had confirmed the presence of myotonia ...

Myotonia congenita is a disorder that affects muscles used for movement. Beginning in childhood people with this condition experience bouts of sustained muscle tensing (myotonia) that prevents ...