THE FEMUR 439 



splint, and extension by weights, etc. have been replaced by 

 that introduced by Whitman. The limb is abducted, so that 

 the proximal fragment is forced against the anterior part of the 

 capsule by the neck and the broken surfaces are brought into 

 apposition. The limit of normal abduction is determined by 

 a comparison with the sound limb, and the fractured limb is 

 maintained in this position, and with the capsule tense, by a 

 plaster case. When the limb is adducted after union has 

 occurred, the head rotates upwards, and it is found that there 

 is little or no .shortening. 



2. Fractures through the distal part of the neck of the femur, 

 although occasionally caused by indirect violence, are commonly 

 due to falls on the greater trochanter. Owing to the line of the 

 femoral attachment of the capsule (p. 420) the fracture is 

 intra-capsular anteriorly but extra- capsular posteriorly. When 

 the injury is due to direct violence, the neck is frequently driven 

 into the greater trochanter, where it may remain impacted, or 

 the trochanter may be comminuted. In the latter condition 

 there is considerable widening of the bony prominence in an 

 antero-posterior direction, and this is more readily determined 

 owing to the relaxation of the ilio-tibial tract. 



When the fracture is not impacted there is definite shortening, 

 and the limb is everted, partly owing to its weight and partly 

 owing to the lateral rotator muscles, which are much stronger 

 than the medial rotators. In impacted fractures these signs ' 

 may be entirely lacking and, in addition, there may be some 

 slight power of movement at the joint. 



As this variety of fracture usually occurs in healthy adults, 

 good bony union is generally obtained, but care must be taken 

 to ensure a proper alignment of the limb and prevent shortening. 



Fractures of the Shaft of the Femur. When due 

 to indirect violence the fracture is usually oblique or spiral, and 

 the fragments tend to override one another. The displacement, 

 therefore, is greater in amount than it is in fractures due to 

 direct violence, where the break tends to be transverse. The 

 degree of displacement depends on the direction of the causative 

 force, the action of muscles, and the influence of gravity. 



In Fracture of the Proximal Third of the Shaft the 

 proximal fragment becomes abducted and laterally rotated by 

 the muscles attached to the greater trochanter, and it is flexed 

 by the ilio-psoas. The amount of flexion is increased, as the 

 distal fragment, which is drawn proximally by the hamstrings 



