[43] "A Treatise on Medical Electricity," second edition, Longmans.
[47] "Les Paraplegies et l'Ataxie du Mouvement." Par S. Jaccoud. Paris, 1864.
Of all the diseases which superficially resemble neuralgia, none are so likely to be confounded with it, on a cursory glance, as myalgia. More careful inquiry, however, furnishes, in nearly all cases, ample means for distinguishing between the two affections.
Myalgia is an exceedingly painful affection, and it is also much more common than was formerly supposed. It is to Dr. Inman that we undoubtedly owe the demonstration of the frequent occurrence of this malady, and the facility with which it may be mistaken for other, and sometimes much more serious, diseases, with very disastrous results. At the same time, I must express the opinion that this ingenious author has decidedly exaggerated the importance of this local disease at the expense of an unjust depreciation of the frequency and significance of other painful disorders which have their origin within the nervous system.
Myalgia proper includes all those affections which are severally known as "muscular rheumatism" (for the muscles generally), and "lumbago," "pleurodynia," etc. (according to locality). It is essentially pain produced in a muscle obliged to work when its structure is imperfectly nourished or impaired by disease.
The clinical history of the different varieties of myalgia absolutely requires this key for its interpretation; otherwise, the appearance of the sufferers from different kinds of myalgia is so widely dissimilar that we should be exceedingly likely to miss the important features of treatment, which must be applied to them all in common. Nothing, for instance, can be more strikingly unlike than the appearance of the pallid, stunted, under-nourishment cobbler who complains of epigastric myalgia, and that of the ruddy and muscular navvy who suffers from acute lumbago, or the similarly plethoric-looking country commercial traveller, who has been driving in his gig against wind and rain, and complains of violent aching pains in one or both shoulders; yet one and all of these individuals are suffering from precisely the same cause of pain, viz., a temporarily crippled muscle or set of muscles which has been compelled to work against the grain. Why this state of things should invariably be interpreted as sensation in the form of acute pain never absent, but severely aggravated by every movement of the affected part, is a matter beyond our powers of explanation, we must accept it as an ultimate fact for the present.