PARATHYROID GLANDS 603 



by extensive tonic spasm, owing to the peculiar and specific hyperexcita- 

 bility that exists. 



Schlesinger found the leg phenomenon positive 18 times in 19 cases 

 studied He regards it, accordingly, as one of the most constant and 

 important symptoms of tetany. The phenomenon is, furthermore, demon- 

 strable in the different forms of tetany; for in his positive observations 

 (including those made on 9 men, 5 women and 4 children) the majority 

 were on cases of idiopathic tetany of workmen, two were on cases of 

 tetania lactantium, and several were on cases of the tetania inf antum of 

 Escherich. 



The leg phenomenon may sometimes be elicited very quickly, even 

 within a few seconds. Sometimes the time of appearance of the phenom- 

 enon differs in the two lower extremities of the same patient; thus, in 

 one instance, one extremity responded after twenty seconds, the other 

 only after fifty seconds had elapsed. In several instances the .cramp was 

 producible in one leg only. In one case the cramp appeared first in the 

 leg under examination and then appeared also in the leg of the opposite 

 side not under test. 



The attitude assumed by the foot is by no means always the same; 

 sometimes there is maximal supination, so that the two soles are turned 

 towards each other; But sometimes there is pronation with adduction. 

 The toes are sometimes spread and extended; at other times they are 

 spread and flexed. Occasionally plantar flexion of the foot is marked. 



Though the occurrence of the leg phenomenon usually runs parallel 

 with that of the Trousseau phenomenon in the upper extremities and 

 sometimes with that of its analogue in the lower extremities, this parallel- 

 ism cannot always be observed. In one of Schlesinger's cases the Leg phe- 

 nomenon appeared several days earlier than the Trousseau phenomenon. 



The leg phenomenon seems to be pathognomonic for tetany. When it 

 ceased to be elicitable in a case of tetany, Schlesinger found that, like 

 the other symptoms, it could again be called forth after subcutaneous ad- 

 ministration of epinephrin. Thus, within a variable period (a few min- 

 utes to an hour) after the epinephrin was administered, the leg phe- 

 nomenon again became positive, the positivity continuing for several hours 

 after the injection. 



3. The Increased Electrical Excitability of the Motor 



Nerves in Tetany 



Erb's Phenomenon 



Though both Kussmaul and Benedict had noticed an increased reac- 

 tion of the motor nerves to stimulation by feeble electric currents in 



