146 ARTHROLOGY, OR ANATOMY OF ARTICULATIONS 



by posterior part of the capsule and the ischiocapsular ligament; 

 extension is checked by the anterior part of the capsule and the 

 iliofemoral ligament; rotation out, by the upper arm of the 

 iliofemoral; rotation in, by the ischiocapsular and ischiofemoral 

 ligaments; abduction, by the pubofemoral ligament and the 

 lower and inner parts of the capsule and impact of the head 

 of the femur; adduction, by the upper arm of the Y-ligament, 

 by the iliotrochanteric ligament, and by soft parts. 



Iliofemoral ligament checks extension and tendency to tip 

 backward, rotation out, and adduction. Pubofemoral checks 

 abduction. Ischiofemoral checks rotation in, extraordinary 

 flexion. 



The Knee-joint 



This is a double condylar joint, really consisting of three 

 articulations, one between each condylc and the tibia, one 

 between the patella and femur which is partly arthrodial. 

 The ligamentum mucosum indicates the original separation 

 of the synovial sac into two. 



The bones are covered by hyaline cartilage to the average 

 depth of j inch (4 mm.). On the anterior part of the condylar 

 surface is a transverse groove caused by indentation of the 

 fibrocartilages; the part above this groove articulates with 

 the patella. 



The ligaments are: Capsular, anterior or ligamentum patellae, 

 posterior, internal lateral, two short external lateral, anterior or 

 external crucial, posterior or internal crucial, two semilunar 

 fibrocartilages, transverse, and coronary. 



The capsular ligament consists of thin but strong fibrous 

 membrane, which is strengthened by heavy bands, inseparately 

 connected with it. In front it blends with and forms part 

 of the lateral patellar ligaments and fills in the space between 

 the anterior and lateral ligaments, blending with them. Above 

 it is deficient. Behind it the fibers are mostly vertical, and 

 are attached above to the condyles and intercondyloid notch 

 of the femur; below they are attached to the posterior part 

 of the head of the tibia, uniting with the origins of the gastroc- 

 nemius, plantaris, and popliteus muscles. It is connected to 

 the posterior ligament. 



