ARTICULATIONS 9 



The costo-clavicular or rhomboid ligament : a strong band 

 of fibres passing backwards, upwards, and outwards from the 

 upper surface of the sternal end of ist costal cartilage, to a 

 rough marking on the under surface of the inner end of the 

 clavicle. 



The interarticular fibro-cartilage is a nearly circular plate, 

 thicker at the circumference than in the centre. It is attached 

 above to the upper border of the clavicle, and below to the ist 

 costal cartilage at its junction with the sternum. There are 

 two synovial membranes, one on each side of the cartilage. 



II. SCAPULO-CLAVICULAR ARTICULATION. 



(a) Acrormo-clavicular, an arthrodial joint held together by 

 the following ligaments : 



The superior acromio-clavicular ligament passes between 

 the outer end of the clavicle and the upper surface of the 

 acromion. 



The inferior acromio-clavicular ligament covers the joint 

 below, being attached to the clavicle internally, and the acro- 

 mion externally. 



An interarticular fibro-cartilage, rarely complete, usually 

 occupies the upper half of the joint. When it is complete, 

 there are two synovial membranes. 



(ft) The toraco-clavicular ligaments connect the clavicle and 

 the coracoid process of the scapula ; they are : 



The trapezoid ligament (the anterior and external one) : 

 attached below to the posterior half of the upper surface of 

 the coracoid process, and above to the oblique line on the 

 under service of the clavicle. It is in contact posteriorly 

 with the conoid ligament. 



The conoid ligament (the posterior and internal one) is 

 attached above by its base, to the conoid tubercle on the 

 inferior surface of the clavicle, and the contiguous part ; by 

 its apex to a rough depression at the base of the coracoid 

 process. 



III. PROPER SCAPULAR LIGAMENTS. 



The coraco-acromial ligament passes over the shoulder- 

 joint between the coracoid and acromion processes. Ex- 

 ternally it is attached to the tip of the acromion, and internally 

 to all the outer border of the coracoid process. 



The transverse or suprascapular ligament stretches over 

 the notch on the upper border of the scapula, and converts 

 it into a foramen. 



