6 60 LEWELLYS F. BAKKEE 



however, of the different forms of tetany, and investigations along experi- 

 mental physiological lines, have strongly indicated the pathogenetic signi- 

 ficance of the parathyroid glands in every form of tetany. I think that the 

 more conservative clinicians have, however, been right in holding their 

 minds open, for it is not at all inconceivable that in the last analysis tetany 

 may be due to some disturbance of intermediary metabolism that is caused 

 often by parathyroid insufficiency but sometimes by conditions other than 

 hypoparathyroidism. 



Experimental removal of the thyroid and parathyroid glands simul- 

 taneously in animals gives rise in them to all the well known signs of 

 tetany and, in addition, to spastic contractures, to intention spasm and 

 sometimes to epileptiform convulsions. There is often in these animals, 

 as in spontaneous tetany in human beings, marked fluctuation of the symp- 

 toms. The striking agreement between this tetania thyroparathyropriva 

 of animals and the tetania strumipriva of human beings lends support to 

 the view that the tetany in these experimental animals depends upon the 

 loss of their parathyroid glands and has the same physiological basis as the 

 tetany appearing in the tetania strumipriva of man. 



When one examines comparatively the other forms of human tetany, 

 including the idiopathic tetany of workmen, the tetany associated with 

 gastrointestinal disturbances, the tetany in acute infectious diseases and in 

 intoxications, the tetany of maternity, and the tetany of childhood, the 

 remarkable agreement as regards the symptoms presented, despite the 

 manifold conditions of their occurrence, is very striking. The galvanic and 

 the mechanical excitability of the nerves is increased, the muscle spasms 

 determine an obstetrical position of the hands, and, in addition, spasms of 

 isolated muscles, of muscle groups, or of the musculature as a whole, are 

 common to them all. Moreover, in all of them too, as Pineles has empha- 

 sized, spastic contractures, flaccid pareses, myotonic symptoms, epilepti- 

 form atttacks, and rapid changes of the individual symptoms, are a com- 

 mon feature. Instances of the latter group of symptoms may only occa- 

 sionally be met with among members of a group, but they are not with the 

 same regularity met with in simulating pathological conditions like tetanus, 

 genuine epilepsy, or the eclampsia of pregnancy. The same may be said of 

 tho trophic disturbances that involve the ectodermal structures (hair, nails, 

 teeth, crystalline lens), for they are all met with in the several different 

 forms of tetany, a fact that is very well illustrated in the accompanying 

 table (see next page) translated from an article by Pineles. 



Examination of tliis table will quickly convince any one of the striking 

 agreement that exists between human tetania strumipriva on the one hand, 

 and tho other forms of tetany in human beings, including the so-called idio- 

 pathic, on the other. The agreement is closest, perhaps, between tetania 

 strumipriva and tetany of workmen, doubtless because these two forms 

 have been better studied and occur more frequently than the other forms. 



