MECHANISM OF THE KNEE-JOINT. 231 



X. ON THE MECHANISM OF THE KNEE-JOINT.* 



THE physiology of the locomotory system, and especially that 

 of the joints, has been hitherto much neglected. Even in 

 Henle's elaborate System of Anatomy, now in course of publi- 

 cation, there is a lingering tendency to adhere to the formal 

 method of description ; and though presenting much freshness 

 and minuteness of description in his account of the articu- 

 lations, he has scarcely done justice to the results latterly 

 attained by the physical physiologists in this department 

 of the science. 



The first step towards an anatomy of the joints adequate 

 to the physiology of the locomotory system that is, an 

 anatomy based on details affording data for precise mechanical 

 investigation was taken by Ed. and Wilh. Weber. f 



As bearing on my present communication, I shall merely 

 indicate the more important results obtained by the Webers 

 in their examination of the knee-joint, as these appear to me 

 to involve the first germ of the correct conception of the me- 

 chanical constitution of the diarthrodial joints. 



1. The knee-joint cannot be considered as a hinge-joint, 

 inasmuch as it does not present a fixed axis. 



2. The femoral condyles roll, and at the same time glide, 

 like a wheel partially restrained by the drag, forwards in 



* This paper was read in detail before the Koyal Society of Edinburgh, 

 January 18, 1858, but only an abstract was printed in the Proceedings of that 

 date. As the essay was found in its complete form amongst the author's 

 papers, we reproduce it here in extenso. EDS. 



t Meckanik dcr Menschlichen Gehwerkzeuge : Gbttingen 1836. 



