V. BONES OF THE THORACIC EXTREMITIES.
Scapula
([Figs. 44] and [45]).—The scapula may be described as a flat triangular bone with one angle rounded. It lies beneath the muscles on the lateral face of the thorax near its cranial end. From its lateral surface there projects a flat ridge ([Fig. 44], g), the spine of the scapula. The ventral end of the ridge is free as a curved process, the acromion process ([Fig. 44], j).
[Fig. 44].—Scapula, Lateral Surface.
![[Fig. 44]](#3418956513767812439_illo062alg.jpg.id-6956513101920650533.wrap-0.html.html){kind=link}
[Fig. 45].—Scapula, Medial Surface.
![[Fig. 45]](#3418956513767812439_illo062blg.jpg.id-7020165170844278460.wrap-0.html.html){kind=link}
I, fossa supraspinata; II, fossa infraspinata; III, fossa subscapularis; IV, fossa for teres major. a, vertebral border; b, coracoid border; c, glenoid border; d, glenoid angle and fossa; e, coracovertebral angle; f, glenovertebral angle; g, spine; h, tuberosity of the spine; i, metacromion; j, acromion; k, supraglenoidal tubercle; l, incisura scapulæ; m, coracoid process; n, groove indicating portion of spine; o, o′, ridges for attachment of muscle-fibres.
The ventral angle of the scapula (d), the glenoid angle (lateral angle of human anatomy), is much heavier than the others and bears a concave, pear-shaped articular facet, the glenoid fossa, for articulation with the humerus. The border with which this angle is more nearly continuous may be called the glenoid border (c) (axillary border of human anatomy).
Near the narrower cranial end of the glenoid fossa is a small curved projection of the bone, the coracoid process ([Fig. 45], m). The border upon which it lies is the coracoid border (b) (superior border of human anatomy). The third border is turned toward the vertebral column and is the vertebral border (a).