THE REGION OF THE KNEE 451 



Ossification of the Distal Extremity of the Femur. A 



secondary centre appears in the cartilaginous distal extremity 

 of the femur during the ninth month of fcetal life. It is the 

 earliest secondary centre to appear, and following the general 



FIG. 130. Knee-joint of Child, aged thirteen. Lateral view. Observe the 

 epiphyseal lines on the tibia and fibula. A separate centre of ossification 

 is present for the tibial tuberosity. Note also the position of the head 

 of the fibula. 



rule that epiphyses which ossify early unite late, it does not 

 join the diaphysis till the twenty-first year. Growth in length, 

 therefore, proceeds for a longer period at the distal than at the 

 proximal extremity of the femur (p. 420). The distal epiphyseal 

 line corresponds, anteriorly, to the proximal border of the 

 articular surface, and posteriorly, to the intercondylar line. 



29 a 



