scapula

scapular anatomy muscles actions
Scapula
The scapula is a flat triangular bone (Fig. 9.7) that lies on
the posterior chest wall between the 2nd and 7th ribs. On
its posterior surface, the spine of the scapula projects backward.
The lateral end of the spine is free and forms the acromion,
which articulates with the clavicle. The superolateral
angle of the scapula forms the pear-shaped glenoid cavity,
or fossa, which articulates with the head of the humerus at
the shoulder joint. The coracoid process projects upward
and forward above the glenoid cavity and provides attachment
for muscles and ligaments. Medial to the base of the
coracoid process is the suprascapular notch (Fig. 9.7).
The anterior surface of the scapula is concave and forms
the shallow subscapular fossa. The posterior surface of the
scapula is divided by the spine into the supraspinous fossa
above and an infraspinous fossa below (Fig. 9.5). The inferior
angle of the scapula can be palpated easily in the living
subject and marks the level of the 7th rib and the spine of
the 7th thoracic vertebra.