334 Anatomy Applied to Medicine and Sutgety. 



split into two planes or laminae which diverge from one 

 another, so that, while one passes in the direction of the 

 centre of the trochanter, the other forms the remaining 

 portion of the posterior wall, and the result of this bifur- 

 cation is, that the latter wall is much weaker and more 

 friable than the anterior. Fracture of the. neck may be 

 intracapsular, extracapsular or mixed, i.e., partly intra 

 and partly extracapsular. Intracapsular occurs, gener- 

 ally, in elderly people, because of the relative weakness of 

 the femoral neck that is present in old people, the result of 

 the absorption of the cancelli. Merkel considers the fra- 

 gility of the neck as due to the disappearance of the "cal- 

 car femorale," which, in the newly-born, is absent, but 

 which reaches its maximum development in middle life, to 

 disappear in old persons. Intracapsular fracture occurs, 

 as a rule, from slight injuries, such as tripping, etc., and 

 under these circumstances, may be the result of muscular 

 action rather than from the effects of the fall. Shorten- 

 ing is generally present in this variety of fracture and 

 averages about one inch and should be measured with the 

 patient perfectly straight on a level surface and with both 

 limbs exposed. The pelvis should be perfectly -transverse 

 and the tape should be accurately applied to the lower edge 

 of the anterior superior spine of the ilium, above, and to the 

 internal or external malleolus, below, and the measure- 

 ment of the sound should be compared with that of the in- 

 jured limb. In connection with shortening, it is necessary 

 to consider Nelaton's line and Byrant's ilio-femoral tri- 

 angle, since these terms indicate methods that are of im- 

 portance in the diagnosis of certain injuries to the hip 

 joint. The former, i.e., Nelaton's line, is the line drawn 

 from the anterior superior spine to the most prominent 

 part of the tuber ischii. The top of the trochanter is, in 

 every position of the normal limb, in some part of this line, 



