yo Anatomy Applied to Medicine arid Surgery. 



Dislocation at the Elbow Joint. Of the differ- 

 ent forms of dislocation that may occur at this joint two 

 only, will be considered, viz: Dislocation of both bones 

 backwards and dislocation of the radius downwards, i.e., 

 by elongation. The latter form of displacement, i.e. of the 

 radius downwards, is peculiar to childhood and is pro- 

 bobly more common than is generally believed. The 

 size of the radial head is an important factor in 

 its production, since, in the child, the head of the 

 radius is comparatively small and is held in its place 

 by a fibrous ring, the orbicular ligament. This ring is 

 narrower below than above, and, when sudden traction 

 with or without torsion, is applied to the radius, the head 

 of the bone may be pulled down and out of the ligament 

 like a button out of a button-hole. This accident occurs 

 not infrequently in children, especially in those of a tub- 

 ercular tendency in whom the ligaments may be more or 

 less lax, and it is generally produced by suddenly lifting 

 a child by one hand, as in dragging it over some obstacle, 

 such as a puddle of water, &c. , or in swinging it down 

 from a height. When the dislocation occurs, the child 

 screams and the arm is rendered useless, but, inasmuch 

 as reduction is often spontaneous, it may be possible 

 that, by the time the surgeon sees the patient, it has 

 become reduced spontaneously. Should the dislocation 

 persist, however, then the forearm is slightly flexed and 

 may be in a position of either pronation or supination and 

 the child will resist any movement of the forearm in 

 an opposite direction, but there is very little, it any, 

 deformity at the joint itself, perhaps only a slight separ- 

 ation of the head of the radius from the humerus. 



To reduce the displacement, extend the forearm and 

 pronate it, if it be already supinated, and then flex suddenly. 

 If, however, it be pronated, extend and supinate. Dislo- 



