142 



BOXES OF THE SHOULDER. 



situ. The clavicle (1) is seen resting its internal head upon the 



Fisr. 144. 



first bone of the sternum, 

 and having its external 

 end attached by ligaments 

 to the acromion process 

 of the scapula ; the clavi- 

 cle maintains the shoulder 

 at a fixed distance from 

 the trunk. 



[ 2/0. THE SCAPULA 

 is a large flat bone, situ- 

 ated on the upper and 

 external part of the back. 

 It is of a triangular 

 form, and at its upper 



. * L 

 and external angle expands to form a shallow cavity, called 



Fig. 145. 



Fig. 146. 



the glenoid cavity (4), in which the head of the humerus 

 is received ; on the upper part of the body a prominent 

 ridge of bone rises (13), which passes upwards and out- 

 wards, and terminates in the acromion process (14), which 

 is expanded over the top of the joint, forming the bony 

 projection of the shoulder. The coracoid process (16) 

 is attached by a thick root to the anterior and upper part 

 of the neck of the bone (5), and curves forwards and out- 



