Myotonia Atrophica.

Abstract

THE object of this paper is to draw attention to a group of cases which present the rare association of muscular atrophy with a slow relaxation of muscles after voluntary contraction. The muscular atrophy has a distribution which is peculiar and corresponds to none of the wellknown types of myopathy. The characteristic features of the condition are weakness of the facial muscles (myopathic face), atrophy of the sterno-mastoids, atrophy of the vasti of the thighs and dorsiflexors of the feet, and a slow relaxation of certain muscles after contraction. The more forcible the contraction, the slower the relaxation. We are aware that variations from the type have been described both in the distribution of the muscular atrophy and in the occurrence of the slow relaxation without atrophy, but considering the striking resemblances of our own cases, and those which we have collected from the literature, we think the type is worthy of recognition. NAME. This condition has been described under various names: Myotonia with muscular atrophy (Lannois). Muscular atrophy with the electrical reactions of Thomsen's disease (Lortat-Jacob et Thaon). Thomsen's disease with muscular atrophy (Nogues et Sirol). Atypical forms of Thomsen's disease (Pelz). Muscular-atrophy with slow relaxation of muscles (nachdauernde MuskeLkontractionen) (Kleist). Myotonia atrophica (Rossolirno and others). We have adopted that of " myotonia atrophica," first used by Eossolimo, because it serves shortly to describe the salient features, and because it is the name under which several authors have since described this condition.

Myotonic Dystrophy – A Multisystem Disease Report of 67 Cases and a Review of the Literature

“…T here are m o stly y oung m en involved [12]. T he ra tio of incidence in m en as com pared to w om en in one series was 1 :5 an d in an o th er 1:1 [13,14].…”

“…C onsanguinity p ro b a b ly does n o t p la y a p a rt. T he ra te of stillb irth s an d in fan tile m o rta lity is high [8,12,17]. M arshall an d Thomas exam ined th e n u clear sex ch ro m a tin p a tte r n in 19 p a tie n ts an d fo u n d co m p atib ility betw een geno-and p h en o ty p e [18].…”

“…T he second p ath o g en etic fa cto r is a " h y p o v en tilatio n sy ndrom e" -an im p a irm e n t of alveolar v en tila tio n caused b y a w eakness of th e chest bellows [12,31,45,61,62,63,64]. M yotony of th e d iap h rag m [45,63], u n ilatera l elevation of th e d iaphragm [45] an d ab n o rm al response (apnea) to a n a sth e tic m aterials [48] are noted in MD cases.…”

Transgenic mouse models for myotonic dystrophy type 1 (DM1)

“…Myotonic dystrophy (DM), also known as dystrophia myotonica or Steinert disease, and first described about one hundred years ago (Batten and Gibb, 1909;Steinert, 1909), is the most common form of muscular dystrophy among adults, with an estimated incidence of 1:8000 (Harper, 2001). Manifestation of disease is highly variable and typically consists of a combination of muscular, neural and endocrine features, each of which may vary in severity with much variation in the age of onset.…”

Fecondite et mortalite infantile dans la dystrophie myotonique au Saguenay-Lac-St-Jean (Quebec Canada)

“…Batten et Gibb (1909) ne sont pas les premiers à avoir décrit des cas de DM. Cependant, depuis la publication de Thomsen (1876) sur la myotonie congénitale (maintenant connue sous la nom de maladie de Thomsen) jusqu'aux travaux de Steinert, une certaine confusion existait entre les deux maladies, certains cas étant considérés comme étant des cas de maladie de Thomsen atypique ou encore des cas de myotonie congénitale avec atrophie musculaire (Erb 1886;Curschmann 1906).…”