588 LEWELLYS F. BARKER 



the reader to a review of the diagnosis and therapy of tetany by Chvostek 

 (d), junior {1909) ; to that of the myotonic symptoms of tetany by von 

 Orzechowski (1909) ; to that of the relations of tetany to epilepsy by Red- 

 lich (1911) ; and to that of the autonomic phenomena of tetany by Fait a 

 and Kahn (1911). Of the general reviews of the subject of tetany, in 

 addition to the older monographs of Oddo and of von Frankl-Hochwart, 

 may be cited that of Risien Russell in Allbutt's System, that of Phleps 

 in Lewandowsky's Handbuch der Neurologic, that of Eppinger in 

 Kraus and Brugsch's Spezielle Pathologie und Therapie, and, especially, 

 that of Biedl in the last edition of his Innere Sekretion. 



III. Symptomatology of Tetany 



By far the majority of the symptoms and signs in tetany are referable 

 to a hyperexcitability of the nervous system. This hyperexcitability in- 

 volves the motor apparatus, the sensory apparatus, and the autonomic 

 apparatus. When the hyperexcitability is of high grade, intermittent 

 attacks of spontaneous tonic contractions of muscles occur (manifest 

 tetany). When the hyperexcitability is somewhat less marked (latent 

 tetany), there are no attacks of spontaneous tonic contractions, but the 

 evidences of hyperexcitability can be easily elicited by means of special 

 tests. The so-called 'tetanoid' states are also to be regarded as examples 

 of latent tetany and are sometimes described as the formes frustes of 

 tetany. 



1. The Tonic Contractions of the Muscles in Manifest 



Tetany 



The tonic contractions of the muscles that appear spontaneously in 

 (manifest) tetany have been observed by all physicians of large experience, 

 and have, long since, been very accurately described. The French phy- 

 sicians, especially, in their early studies of tetany, made careful analyses 

 of the muscular spasms in tetany and of the pathological attitudes of the 

 different parts of the body that result from them. This is a form of 

 observation and description in which French clinicians are known par- 

 ticularly to excel. 



In adults the tonic spasms of the musculature in manifest tetany occur 

 most frequently in the upper extremities, less frequently in the lower ex- 

 tremities, and less frequently still in the muscles of the head, neck and 

 trunk. In children it is common to have the upper and lower extremities 

 simultaneously involved in the muscular spasms of tetany. In both adults 

 and children the hyperkinesis of tetany occasionally may be so marked 

 as to constitute a general convulsion. 



In the classical form of tetany, the attitude assumed in the attack 



