Right Scapula Bone: Posterior Markings
a. Superior border or margin (Margo superior) is the upper edge of the scapula that runs next to the clavicle. The omohyoid muscle attaches along this surface.
b. Medial border or margin (Margo medialis) is the medial edge of the scapula and is also called the vetebral border. This area is an attachment point for the rhomboid major, rhomboid minor and serratus anterior muscles.
c. Lateral border or margin (Margo lateralis) is the lateral edge of the scapula. The teres minor muscle attaches along this surface, which is also called the axillary border.
d. Superior angle (Angulus superior) is a sharp curvature at the junction of the superior and medial borders. This area is an attachment point for levator scapula muscle.
e. Lateral angle (Angulus lateralis) is the junction of the superior and lateral borders. Its slightly concave lateral edge articulates with the head of the humerus.
f. Inferior angle (Angulus inferior) is a sharp curvature formed at the junction of the medial and lateral margins. It is an area of attachment for the teres major muscle.
g. Scapular spine (Spina scapulae) is a long ridge that runs diagonally across the upper posterior surface of the bone. The trapezius and posterior deltoid muscles attach to the surface of this prominent elevation.
h. Acromion (Acromion scapulae) is a lateral, fan-like extension of the spine. It also is an attachment point for the trapezius and posterior deltoid muscles.
i. Supraspinous fossa (Fossa supraspinata) is a slightly depressed area located superior to the spine. The supraspinatus muscle attaches to this region of the scapula.
j. Infraspinous fossa (Fossa infrspinata) is a large, slightly depressed area located inferior to the spine. It serves as an attachment point for the infraspinatus muscle.
k. Glenoid cavity or fossa (Cavitas glenoidalis) is a slight concavity at the lateral angle. It forms a shallow socket for the articulation of the head of the humerus.
l. Infraglenoid tubercle (Tuberculum infraglenoidale) is a small prominence on the inferior margin of the glenoid fossa. The long head of the triceps brachii muscle attaches to this knob-like ridge.