150 



Anatomy of Skeleton 



FIG. 123. Lower end of right femur. T. 

 trochlear surface, for patella, extend- 

 ing along inner condyle as an area 

 with which patella articulates in 

 flexion ; M . menisco-tibial surfaces 

 for resting on tibia in extension. 

 The nbro-cartilages make marks by 

 their front borders on the femur at c. c. 



impressions made by these are visible (Fig. 123) in the recent state, and usually also in 



the dry bones. 



The whole continuous articular surface can be divided into three portions, two 



condylar and one trochlear surface, the latter being for the play of the patella ; 



a prolongation of the trochlear surface downwards and backwards along the inner 



condyle, shown in Fig. 123, is in contact with 

 the patella when the leg is flexed. These three 

 parts were originally distinct, and the remains 

 of the dividing walls are seen in the ligamenta 

 alaria and mucosum. Ligamentum mucosum 

 is attached to the front end of the intercondylic 

 fossa, and extends from this as a synovial band 

 to the lower end of the patella : it marks the 

 line of the septum separating the two condylar 

 cavities, and the ligamenta alaria are remains 

 of the walls cutting them off from the trochlear 

 sac (Fig. 124). 



The whole lower end is formed from a 

 single centre of ossification, making a pressure 

 epiphysis which is one of the earliest of this class 

 to appear in the body. It is formed in the 



middle of the cartilaginous end at or just before birth, a fact of some interest 



and importance in certain medico-legal inquiries. The epiphysis is that of the growing 



end of the bone, and the epiphysial line (Fig. 122) runs through the Adductor tubercle, 



above the Gastrocnemius facets, and a little distance above the articular surfaces, 



curving slightly downwards on the sides of 



the condyles. Thus there are attached to the 



epiphysis : 



(1) The posterior ligaments of the 



capsule and the lateral liga- 

 ments ; 



(2) Crucial ligaments and Liga- 



mentum mucosum ; 



(3) Outer head and part of inner 



head of Gastrocnemius, with 

 Plantaris in part ; 



(4) Popliteus. 



The greater part of the epiphysis is in 

 relation with the joint cavity, it being only 

 otherwise covered by the Vasti on each side 

 over a small area. 



Fig. 125 is a scheme to illustrate the 

 disposition of lamellae in the construction of 

 the bone. 



The femur can be directly examined 

 only towards its ends during life, its shaft being indirectly palpable through the 

 mass of extensor muscles. The great trochanter is easily felt, being only covered 

 over its greater part by the aponeurosis of the Gluteus maximus, although the 

 tendon of Gluteus medius somewhat obscures its upper front portion. Its breadth, 

 etc., can be appreciated by the fingers, and comparison made with the other 



FIG. 124. A left knee at birth, showing an 

 unusual condition of the ligam. mucosum, 

 which is represented by a complete septum 

 between the two condylar parts of the cavity. 

 The ligamenta alaria are seen as wing-like 

 folds at each side of the lower end of the 

 patella : they are remains of septa shutting 

 off the trochlear from the condylar cavities. 



