320 THE ARTICULATIONS OR JOINTS. 



LIGAMENTS OF THE SCAPULA. 



These ligaments are not directly connected with any articulation. 



Lig. Coracoacromiale. The coraco-acromial ligament (Fig. 302) completes the 

 arch between the coracoid process and the acromion, and thus provides a secondary 

 socket for the greater protection and security of the shoulder-joint. It is a flat 

 triangular structure stretched tightly between its attachments. By its base it is 

 fixed to a varying amount of the postero-lateral border of the coracoid process, 

 and by its narrower apical end to the tip of the acromion, immediately lateral to the 

 acromio-clavicular joint. Its surfaces look upwards and downwards, and its free 

 borders laterally and medially. It is thinnest in the centre, where it is sometimes 

 perforated by a prolongation of the tendon of the pectoralis minor muscle. 



Lig. Transversum Scapulae Superius. The superior transverse scapular ligament 

 (O.T. suprascapular ligament) is a distinct but short flat band which bridges the 

 scapular notch. It may be continuous with the conoid ligament, and it is frequently 

 ossified. As a rule the foramen completed by this ligament transmits the supra- 

 scapular nerve, while the transverse scapular vessels pass superior to the ligament 

 to reach the supraspinous fossa. 



A small duplicate of this ligament may often be found bridging the foramen on 

 its costal aspect, subjacent to which small branches of the transverse scapular artery 

 return from the supraspinous to the subscapular fossa. 



Lig. Transversum Scapulae Inferius. The inferior transverse scapular ligament 

 (O.T. spino-glenoid ligament) consists of another set of bridging fibres which are 

 situated on the posterior aspect of the neck of the scapula. By one end they are 

 attached to the lateral border of the scapular spine, and by the other to the adjacent 

 part of the posterior aspect of the head of the scapula. The suprascapular nerve 

 and the transverse scapular vessels pass subjacent to this ligament. 



ARTICULATIO HUMERI. 



