450 SURGICAL APPLIED ANATOMY. [Chap. xix. 



usually found near the line of junction of the head 

 with the neck. This fracture is most common in the 

 old, in whom it may be produced by very slight 

 degrees of violence. The liability of the aged 

 to this lesion is explained upon the following 

 grounds. The angle between the neck and shaft 

 of the femur, which will be about 130 in a 

 child, tends to diminish as age advances, so that in 

 the old it is commonly about 125. In certain aged 

 subjects, as a result probably of gross degenerative 

 changes, this angle may be reduced to a right angle. 

 This diminution of the angle certainly increases the 

 risk of fracture of the neck of the bone. There is 

 often also, in advanced life, much fatty degeneration of 

 the cancellous tissue of the cervix with thinning of 

 the compact layer. Dr. Merkel (Amer. Journ. Med. 

 Sc., 1874) also asserts that in old persons there is an 

 absorption of that process of the cortical substance 

 which runs on the anterior part of the neck between 

 the lesser trochanter and the under part of the head. 

 This process he calls the " calcar femorale," and 

 maintains that it occupies the situation at which the 

 greatest pressure falls when the body is erect. These 

 fractures are but rarely impacted; but when impacted, 

 the lower fragment, represented by the relatively 

 small and compact neck, is driven into the larger and 

 more cancellous fragment made up of the head of the 

 bone. The fracture may be subperiosteal, or the 

 fragments may be held together by the reflected 

 portion of the capsule. These reflected fibres pass 

 along the neck of the bone from the attachment of 

 the capsule at the femur to a point on the cervix 

 much nearer to the head. " These reflected fibres 

 occur at three places, one corresponding in position to 

 the middle of the ilio-femoral ligament, another to the 

 pectineo-femoral, and the third on the upper and back 

 part of the neck " (Henry Morris). Fractures of this 



