THE SCAPULA. 141 



upper surface, directed upward, backward, and outward, is convex, rough, and 

 gives attachment to some fibres of the Deltoid, and in the rest of its extent it is 

 subcutaneous. Its under surface is smooth and concave. Its outer border is thick 

 and irregular, and presents three or four tubercles for the tendinous origins of the 

 Deltoid muscle. Its inner margin, shorter than the outer, is concave, gives attach- 

 ment to a portion of the Trapezius muscle, and presents about its centre a small 

 oval surface for articulation with the acromial end of the clavicle. Its apex, which 

 corresponds to the point of meeting of these two borders in front, is thin, and has 

 attached to it the coraco-acromial ligament. 



Borders. Of the three borders of the scapula, the superior is the shortest and 

 thinnest ; it is concave and extends from the superior angle to the coracoid process. 

 At its outer part is a deep, semicircular notch, the suprascapular, formed partly by 

 the base of the coracoid process. This notch is converted into a foramen by the 

 transverse ligament, and serves for the passage of the suprascapular nerve. Some- 

 times this foramen is entirely surrounded by bone. The adjacent margin of the 

 superior border affords attachment to the Omo-hyoid muscle. The external, or 

 axillary, border, is the thickest of the three. It commences above at the lower 

 margin of the glenoid cavity, and inclines obliquely downward and backward to 

 the inferior angle. Immediately below the glenoid cavity is a rough impression 

 (the infraglenoid tubercle], about an inch in length, which affords attachment to 

 the long head of the Triceps muscle ; in front of this is a longitudinal groove, 

 which extends as far as its lower third and affords origin to part of the Subscapu- 

 laris muscle. The inferior third of this border, which is thin and sharp, serves for 

 the attachment of a few fibres of the Teres major behind and of the Subscapularis 

 in front. The internal, or vertebral, border, also named the base, is the longest of 

 the three, and extends from the superior to the inferior angle of the bone. It is 

 arched, intermediate in thickness between the superior and the external borders, 

 and the portion of ic above the spine is bent considerably outward, so as to form an 

 obtuse angle with the lower part. The vertebral border presents an anterior lip, 

 a posterior lip, and an intermediate space. The anterior lip affords attachment 

 to the Serratus magrius ; the posterior lip, to the Supraspinatus above the spine, 

 the Infraspinatus below ; the interval between the two lips, to the Levator anguli 

 scapulas above the triangular surface at the commencement of the spine, the 

 Rhomboideus minor to the edge of that surface ; the Rhomboideus major being 

 attached by means of a fibrous arch connected above to the lower part of the 

 triangular surface at the base of the spine, and below to the lower part of the 

 posterior border. 



Angles. Of the three angles, the superior, formed by the junction of the 

 superior and internal borders, is thin, smooth, rounded, somewhat inclined out- 

 Avard, and gives attachment to a few fibres of the Levator anguli scapulae muscle. 

 The inferior angle, thick and rough, is formed by the union of the vertebral and 

 axillary borders, its outer surface affording attachment to the Teres major and fre- 

 quently to a few fibres of the Latissimus dorsi. The anterior angle is the thickest 

 part of the bone, and forms what is called the head of the scapula. The head 

 presents a shallow, pyriform, articular surface, the glenoid cavity (y^fy, a socket), 

 whose longest diameter is from above downward, and its direction outward arid for- 

 ward. It is broader below than above ; at its apex is a slight impression (supra- 

 glenoid tubercle), to which is attached the long tendon of the Biceps muscle. It is 

 covered with cartilage in the recent state ; and its margins, slightly raised, give 

 attachment to a fibro-cartilaginous structure, the glenoid ligament, by which its 

 cavity is deepened. The neck of the scapula is the slightly depressed surface 

 which surrounds the head ; it is more distinct on the posterior than on the anterior 

 surface, and below than above. In the latter situation it has arising from it a thick 

 prominence, the coracoid process. 



The Coracoid Process, so called from its fancied resemblance to a crow's beak 

 (xbpas, a crow), is a thick, curved process of bone which arises by a broad base 

 from the upper part of the neck of the scapula ; it is directed at first upward and 



