PELVIC LIMBS 689 



upper part. It begins on the inside of the neck, very near the front 

 aspect of the bone, on a level with the lesser trochanter, and is con- 

 tinued straight down to the lower fourth, where it turns gradually 

 backward to become the internal supracondyloid ridge of the lower 







extremity. Through its entire course it lies much nearer the anterior 

 than the posterior aspect of the bone. 



The anterior surface (Fig. 528) lies between the internal and 

 external borders. It is straight from above downward, and strongly 

 convex from side to side. Owing to the posterior situation of the 

 external border and the anterior situation of the internal border in the 

 upper two-thirds of the bone, in this region the greater part of the 

 anterior surface faces forward and outward ; in the lower third the 

 surface is more evenly convex, and faces both outward and inward as 

 well as forward. The upper part, where it passes into the surface of 

 the upper extremity, is rough and marked by foramina for small veins ; 

 the middle part is smooth, and the lower part ends in front at the 

 trochlea of the inferior extremity, and is continued on the sides to 

 form the lateral surfaces of its internal and external tuberosities. On 

 the upper part of the anterior surface in the middle line is the small 

 area of insertion of the tendon of the glutens quartus muscle. To the 

 outside of this area is the triangular area of origin of the vastus ex- 

 ternus, and below and to the inside the common area of origin of the 

 crureus and vastus internus muscles. The rest of the anterior surface, 

 down to the lower fifth, gives attachment to the crureus and vastus 

 internus. 



The posterior surface (Fig. 532) of the femur is convex from side 

 to side, especially above. It is nearly straight from above downward, 

 but at the lower end inclines somewhat backward and downward. Its 

 upper part faces inward as well as backward, and the lower part faces 

 directly backward. It is divided into three areas by the linea aspera, 

 an elevated line, sometimes called the posterior border. 



The linea aspera begins below at the lower fourth of the internal 

 border of the bone, and runs obliquely upward and outward, to end 

 in the external border at the greater trochanter. A little above the 

 middle of its course it gives off another line, which runs directly 

 upward and below the lesser trochanter becomes continuous with the 

 anterior intertrochanteric line. The lower part of the linea aspera is 

 well marked and elevated, and separates the areas of attachment of the 



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