LIGAMENTS OF THE SHOULDER. 



num and clavicle. Below it is thin, where it is attached to 

 the sternum ; above it is thick, where it is connected to the 

 clavicle. Its centre is thin and sometimes perforated. Its 

 structure is fibro-cartilaginous, and its use seems to be to 

 adapt the bony surfaces to one another as well as to bind 

 them together. 



The synovial membranes are two in number, one on each 

 side of the inter-articular cartilage. They are found to 

 contain but little synovia, and are strongly attached to the 

 adjacent surfaces. 



Cos to-clavicular articulation, (Fig. 141.) This articula- 

 tion has a short bundle of parallel ligamentous fibres, 

 called the rhomboid or inferior ligament, running obliquely 

 downward and forward from the inferior surface of the 

 sternal end of the clavicle, to be inserted into the upper 

 surface of the cartilage of the first rib. Posteriorly it is 

 in contact with the subclavian vein, and anteriorly with 

 the subclavian muscle. 



The inter-clavicular ligament is placed at the superior end 

 of the sternum, and extends from the posterior sternal 

 extremity of one clavicle to that of the other. 



Scapulo-clavicular articulation, (Fig. 221.) This articu- 

 lation has a capsular ligament at the junction of the 

 acromion process and clavicle, whose fibres being thick- 

 ened above and below, and passing from one bone to the 

 other, receive the name of superior and inferior ligaments. 

 A synovial membrane, somewhat indistinct, is seen upon 

 the articular surface of this joint, and occasionaly an 

 inter-articular cartilage is found. 



The coraco-clavicular ligament is double, and consists of 

 the conoid and the trapezoid. 



The conoid is the smaller and posterior of the two ; its 

 base is above and attached to the tubercle on the inferior 

 surface of the acromial end of the clavicle. The trapezoid 

 is more anterior and external; it is broader, longer and 

 thinner than the conoid, and is attached above to an 

 oblique line on the under surface of the clavicle at the 

 tubercle, and below. to the root of the coracoid process. 



