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The inter clavicular ligament is a flat band passing in a curved 

 direction between the inner extremities of the clavicles, and 

 is closely attached to the upper border of the sternum. Some 

 of its fibers are connected with the periosteum of the posterior 

 surface of the sternal end of the clavicle, and some with the 

 back of the capsule. So if we follow the course of the connec- 

 tive tissue from the upper border of the clavicle, some goes 

 to the interarticular cartilage, some to the capsule, and some 

 forms the interclavicular ligament. 



The costoclamcular or rhomboid ligament ascends obliquely 

 from the inner part of the cartilage of the first rib back to 

 the depression on the under surface of the sternal end of the 

 clavicle. To its outer side is the subclavian vein. This liga- 

 ment encloses the tendon of insertion of the subclavius muscle, 

 but most of the ligament is behind the muscle, its anterior 

 part being continued as fascia over it. Between the muscle 

 and the posterior part of the ligament is sometimes developed 

 the "bursa of Monro. " Cruveilhier describes this ligament 

 and bursa as the costoclavicuJar articulation. 



Nerves, second and third cervical by descendens noni. 

 Arteries, neighboring muscular branches. Motion is not a 

 gliding, but axial on the fibrocartilage. Elevation and depres- 

 sion of the shoulder produce movement here on a transverse 

 axis through the costoclavicular ligament; movement of shoulder 

 forward and backward, on a vertical axis through the same 

 point. It is an arthrodial joint. 



THE ACROMIOCLAVICULAR ARTICULATION 



The acromioclavicular is un arthrodial joint formed by the 

 outer extremity of the clavicle and the inner margin of the 

 acromial process of the scapula. 



Ligaments are capsular (superior and inferior acromio- 

 clavicular), interarticular fibrocartilage; coracoclavicular, con- 

 sisting of the trapezoid and conoid ligaments. 



There is a weak capsule to this joint, really a fibrous covering 

 of the synovial membrane; it is strongest above, being- 

 strengthened above and below by bands designated by some 

 as the superior and inferior acromioclavicular ligaments. The 

 interarticular cartilage is usually present in some form, either 



