THE KNEE-JOINT 



343 





is thin, concave, and free. The upper surfaces of the menisci are concave, and 

 in contact with the condyles of the femur; their lower surfaces are flat, and rest 

 upon the head of the tibia; both surfaces are smooth, and invested by synovial 

 membrane. Each meniscus covers approximately the peripheral two-thirds of 

 the corresponding articular surface of the tibia. 



The medial meniscus (meniscus medialis; internal semilunar fibrocartilage) is 

 nearly semicircular in form, a little elongated from before backward, and broader 

 behind than in front; its anterior end, thin and pointed, is attached to the anterior 

 intercondyloid fossa of the tibia, in front of the anterior cruciate ligament; its 

 posterior end is fixed to the posterior intercondyloid fossa of the tibia, between 

 the attachments of the lateral meniscus and the posterior cruciate ligament. 



Anterior cruciate ligament 



Transverse ligament 



Ligament of Wrisberg 

 Posterior cruciate ligament 



FIG. 349. Head of right tibia seen from above, showing menisci and attachments of ligaments. 



The lateral meniscus (meniscus lateralis; external semilunar fibrocartilage) is nearly 

 circular and covers a larger portion of the articular surface than the medial one. 

 It is grooved laterally for the tendon of the Popliteus, which separates it from the 

 fibular collateral ligament. Its anterior end is attached in front of the intercon- 

 dyloid eminence of the tibia, lateral to, and behind, the anterior cruciate ligament, 

 with which it blends; the posterior end is attached behind the intercondyloid 

 eminence of the tibia and in front of the posterior end of the medial meniscus. 

 The anterior attachment of the lateral meniscus is twisted on itself so that its 

 free margin looks backward and upward, its anterior end resting on a sloping 

 shelf of bone on the front of the lateral process of the intercondyloid eminence. 

 Close to its posterior attachment it sends off a strong fasciculus, the ligament of 

 Wrisberg (Figs. 348, 349), which passes upward and medialward, to be inserted 

 into the medial condyle of the femur, immediately behind the attachment of the 

 posterior cruciate ligament. Occasionally a small fasciculus passes forward to 

 be inserted into the lateral part of the anterior cruciate ligament. The lateral 

 meniscus gives off from its anterior convex margin a fasciculus which forms the 

 transverse ligament. 



The Transverse Ligament (ligamentum transversum genu). The transverse liga- 

 ment connects the anterior convex margin of the lateral meniscus to the anterior 

 end of the medial meniscus; its thickness varies considerably in different subjects, 

 and it is sometimes absent. 



The coronary ligaments are merely portions of the capsule, which connect the 

 periphery of each meniscus with the margin of the head of the tibia. 



