THE SCAPULA 



143 



The vertebral border (sometimes called the base) is the longest, and extends 

 from the upper or medial to the lower angle of the bone. It is divisible into three 

 parts, to each of which a muscle is attached: an upper portion, extending from 

 the medial (superior) angle to the spine, for the insertion of the levator scapuloe; 

 a middle portion, opposite the smooth triangular area at the commencement 

 of the spine, for the rhomhoideus minor; and the lowest and longest portion, 

 extending below this as far as the inferior angle, for the rho7?iboideus major, 

 the attachment of which takes place through the medium of a fibrous arch. 



The axillary border is the thickest, and extends from the lower margin of 

 the glenoid cavity to the inferior angle of the bone. Near its junction with the 

 glenoid cavity there is a rough surface, about 2.5 cm. (1 in.) in length the in- 

 fraglenoid tubercle, from which the long head of the triceps arises, and below 



Fig. 172. — The Left Scapula. (Ventral surface.) 



Trapezoid ligament Pectoralis minor 



Scapular notch Conoid Ug. 



Serratus anterior 



Coraco-acromial 

 Z^I^^T^^ ligament 



""" Biceps and coraco- 



brachialis 



Clavicular facet 



Biceps 



Glenoid fossa 



Articular capsule 



Triceps (middle or long head) 



Serratus anterior 



the tubercle is the groove for the circumflex (dorsal) artery of the scapula. 

 The upper two-thirds of the border is deeply grooved on the ventral aspect and 

 gives origin to a considerable part of the subscapidaris. 



Angles. — The three angles are named medial, inferior, and lateral. 



The medial (or superior) angle, forming the highest part of the body, is thin, smooth, and 

 either rounded or approximating a right angle. It is formed by the junction of the superior 

 and vertebral borders and gives insertion to a few fibres of the levator scapula. The inferior 

 angle, constituting the lowest part of the body, is thick, rounded, and rough. It is formed bv 

 the junction of axillary and vertebral borders, gives origin to the teres major, and is crossed 

 horizontally by the upper part of the latissimus dorsi, the latter occasionally receivmg from it 

 a small slip of fleshy fibres. 



The lateral angle forms the expanded portion of the bone known as the head, 

 bearing the glenoid cavity, and supported by a somewhat constricted neck. The 



