238 



William Christopher Kraiiss 



arm and leg muscles, and although the figures may vary 

 somewhat at each trial, still they are accurate enough to indi- 

 cate the progress of the wasting. The dynamometer is per- 

 haps the best instrument for estimating the power of the 

 flexors of the fingers and hand muscles. It consists of an 

 oval steel spring with a dial and index in the center. Com- 

 pression of the spring is indicated on the dial in pounds and 

 kilograms. This instrument is by no means accurate or per- 

 fect as each succeeding trial may give a different reading ac- 

 cording to the strength exerted by the patient. It is my prac- 

 tice to take the average of two or three compressions and this 

 result I consider approximately correct. 



For estimating the strength of the 

 legs several appliances have been 

 suggested by Dana, Birdsall, Fere, 

 and d'Onimus, but none have en- 

 joyed universal adaptation among 

 neurologists. An apparatus which I 

 have recently described * approaches, 

 in my opinion, the solution of this 

 problem, and has received the appel- 

 lation, Pedo-dynamovieter. It con- 

 sists of a wide, heavy belt (a), its 

 inner surface padded so that its ad- 

 justment around the waist will not 

 be uncomfortable. A heavy web- 

 bing (^), is looped through the belt 

 passing over the shoulders, which 

 helps to retain the belt in its proper 

 position. A common Mathieu dyna- 

 mometer (c), is connected with the 

 belt {a), by means of a strong ad- 

 justable strap, permitting it to be 

 lengthened or shortened according to 

 the stature of the patient. Con- 

 nected to Ihe dynamometer (<:), is a stirrup (^), the base of 

 which is padded for receiving the foot. Pressure exerted 



Fig. 



*Neurologisches Centralblatt, June i, 1893. 



