Essential Myotonia

Myotonia fluctuans.

Autosomal-dominantly inherited nondystrophic myotonic disorders are an interesting group of muscle diseases that provide considerable opportunity for future molecular genetic studies to identify the genes responsible for specific membrane functions. A family with such a myotonic disorder is described with features that are distinctly different from myotonia congenita and paramyotonia congenita....

Myotonia Acquisita

Ocular Myotonia

Today, we have heard about several rare diseases and I am about to add another to the pile. This seems to me entirely appropriate to this occasion. Malcolm Campbell, as has been said, was a keen student of natural history. He took a special delight in the recognition of an unusual condition. I should like to add my tribute to his memorial. Myotonia is a sustained contraction of muscle fibres ca...

Recessively inherited myotonia congenita.

Electrical myotonia in heterozygous carriers of recessive myotonia congenita.

We investigated electrophysiologically the unaffected parents of patients with recessive myotonia congenita. We studied 18 families, in nine of which the diagnosis was confirmed by molecular genetics. Brief myotonic discharges were present in at least one parent in 67% of the families. Fathers were more likely than mothers to show these discharges. The difficulty in distinguishing very mildly a...