[Von Eulenburg's congenital paramyotonia and aptitude for military service. Cases taken from a family with 25 cases since 1789].
The authors present four cases of von Eulenberg's paramyotonia. From the family history it was possible to follow the condition through seven generations since 1780; it confirms the autosomal dominant nature of genetic transmission, with almost complete penetrance. From the clinical standpoint, the condition observed is particularly pure, occurring exclusively in the cold. At no time were paralyses or adynamia independent of the myotonic phenomena and of temperature variations observed. The laboratory investigations carried out, ionic and enzyme, showed no abnormalities. Electromyographic study showed the presence of numerous true myotonic out-bursts, variable in shape and in amplitude, independant of the myotonic phenomenon, and present in the absence of exposure to cold. The effects of the condition on aptitude for military service are examined and in this respects the author recalls that the history of myotonia is intimately bound up with medico-military problems.