LAWS OF BONE ARCHITECTURE 



249 



PART IV. THE XOmiAL INNER ARCHITECTURE OF THE FEMUR 



For clearness of descrij^tion of the inner architecture of the 

 human femur, it may l^e divided into three parts: the upper 

 femur, shaft and distal portion. The former includes the head 

 and neck and extends to the lower limit of the lesser trochanter. 



= Compression 

 • =Ti?n5'ion 

 <5 =Comp a Tension 

 — Neutral Axi,-- 



Fig. 19 a luten.sity of the maximum tensile and compres.sive stre.sses in the 

 femur-head. Computed for the load of 100 pounds on the right femur. Cor- 

 responds to the upper part of figure 18. 



The shaft includes all that portion of the femur which lies be- 

 tween the lesser trochanter and the distal portion. The distal 

 portion is taken as the lower-most six inches of the femur and 

 includes all that part of the bone in which the shaft gradually 

 increases in size to form the articular surface of the lower end 



