PARATHYROID GLANDS 



601 



different occasions. The response, as described in Pool's patient, grad- 

 ually grew less marked and finally disappeared after about twelve months 

 observation. The positive response for these arm and leg phenomena 

 seemed to run parallel with the positive response of Trousseau's sign as 

 well as with the response of Chvostek's sign. Pool stated, in his first 

 report of the case, that "the value of the two tests, dependent upon 

 stretching the nerves of the brachial plexus and the sciatic nerve, which 

 were so striking in our case, cannot be estimated until repeated trials have 

 been made in other cases." He considered the tests of value as "an ad- 



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Fig. 6. Method of producing tetanic spasm in the feet by stretching the sciatic 

 nerves by means of forcible flexion of the trunk upon the thighs. The onset of the 

 spasm one and a half minutes after the test is applied is well shown. The Leg Phenom- 

 enon of Pool. (After E. H. Pool, Annals of Surgery, 1907.) 



ditional demonstration of the mechanical excitability of the motor nerves 

 by the stretching of the sciatic and the nerves of the brachial plexus." 



It would seem that the arm phenomenon had been earlier observed by 

 the Italian clinician, Ferenczi (1904), in a boy of 14 suffering from 

 typical tetany ; but Ferenczi appears to have viewed this arm phenomenon 

 as identical with Trousseau's sign and to have thought that it afforded 

 evidence that Trousseau's phenomenon is of vasomotor origin, since he 

 found that the radial pulse was scarcely palpable in the abducted arm. 



In 1910, Alexander, apparently without knowledge of Pool's work, 

 observed and reported this arm phenomenon in a case of tetany. 



In the same year Schlesinger (a) (b) of Vienna reported what he desig- 



