#Contusion# in this region, on the other hand, is not uncommon. It is produced by a fall on the trochanter, and gives rise to symptoms which simulate to some extent those of fracture of the neck. The limb lies in the position of slight flexion, but the bony points retain their normal relationship to one another, and there is no shortening. The swelling and tenderness often prevent a thorough examination being made, and when any doubt remains as to the diagnosis, the patient should be kept in bed till the doubt is cleared up by the use of the X-rays. If the bone has been broken, this will reveal itself in the course of a few days by the occurrence of shortening and other evidence of fracture.
In elderly patients, contusion of the hip may be followed by changes in the joint of the nature of arthritis deformans; and it has been stated, although proof is wanting, that absorption of the neck of the femur sometimes occurs. These injuries are treated by rest in bed, massage, and the other measures already described as applicable to sprains and contusions.
This group includes all fractures between that immediately below the lesser trochanter and the supra-condylar fracture.
_In adults_, when due to direct violence, the fracture is usually transverse, and may be attended with comparatively little displacement. Indirect violence, on the other hand, usually produces an oblique fracture, which is frequently comminuted and often compound. The break is most commonly situated a little above the middle of the shaft, the obliquity being downward, forward, and medially, and of such a nature that the fragments tend to override one another (Fig. 75). The most serious forms are those associated with gun-shot wounds.
[Illustration: FIG. 75.--Longitudinal section of Femur showing recent Fracture of Shaft with overriding of Fragments.]
The direction and nature of the displacement depend more upon the fracturing force, the weight of the lower part of the limb, and the action of the muscles attached to the respective fragments, than upon the direction of the obliquity. As a rule, the proximal fragment passes forward and laterally, and is maintained in this position by the ilio-psoas and glutei muscles, while the distal fragment is displaced upward and medially and is rotated outward by the combined action of the weight of the limb, the longitudinal muscles, and the adductors.