THE SHOULDER-GIRDLE. 



231 



As regards treatment, to reduce the luxation the shoulder should be elevated 

 and drawn outward and backward. While pressure is made on the protruding bone 

 the arm is used as a lever and the bone tilted into place. Usually reduction can be 

 readily accomplished, but most people have found it difficult to retain the parts in 



Sternum 



Clavicle 



Subclavius muscle 



Costoclavicular or 

 rhomboid ligament 



First rib' 



Second rib / 



FIG. 243. Dislocation of the sternal end of the clavicle upward and forward, showing how the first rib acts as a 



fulcrum and the clavicle as a lever. 



place. The only sure way of doing so is to keep the patient in bed on his back. 

 Stimson, following Velpeau and Malgaigne, advises the application of an anterior 

 figure eight bandage of plaster of Paris; Hamilton says deformity remains after any 

 method of treatment, but that function 

 will be but little impaired. 



In upward dislocations the case of 

 R. W. Smith has shown that the end of 

 the bone passes behind the sternal origin 

 of the sternomastoid muscle. 



In backward dislocations pressure 

 on the trachea and oesophagus have 

 caused difficulty in breathing and swal- 

 lowing; cyanosis due to pressure on the 

 internal jugular vein has been observed 

 in one case. When one recalls the 

 function of the clavicle in keeping the 

 shoulder out from the body, it is readily 

 seen that when the security of its inner 

 attachment has once been destroyed dis- 

 placement is favored by the weight of 

 the upper extremity as well as by the 

 action of all the muscles which pass 



t 



from the head, neck, and trunk to the 

 shoulder-girdle and humerus. 



In these dislocations of the sternal 



FIG. 244. Luxation of the outer end of the clavicle 

 upward, showing the coracoid process acting as a fulcrum. 

 As the outer end of the clavicle rises, the lower angle of the 

 scapula is carried toward the median line and the acromion 

 process is depressed and torn loose from the clavicle above. 



end of the clavicle the fibrocartilaginous 



disk of the joint sometimes is carried out with the clavicle and sometimes remains 



attached to the sternum, more often it follows the clavicle. 



Dislocation of the Acromial End of the Clavicle. The acromial end of 

 the clavicle may be dislocated either upward or downward. Nearly all the disloca- 

 tions are upward. 



The displacement is usually produced by direct violence, a blow on the top or 

 back of the shoulder driving the acromion down and inward. The clavicle not only 



