The scapula is a triangular bone. Triangles have 3 angles and 3 sides.
The 3 angles of the scapula bone are located towards the upper, lower and lateral (= axillary) surfaces of the scapula. The 3 "sides" of the approximately triangular shape of the scapula bone are not straight (as per strict mathematical triangles) but are curved and are called "borders".
The 3 borders of the scapula are :
The superior border of the scapula is concave (see the diagrams of the posterior surface of the scapula, below and further-below-left) and extends from the superior angle of the scapula to the coracoid process. It is the shortest and thinnest of the three borders of the scapula.
At the lateral (axillary) extreme of the superior border of the scapula there is a deep semi-circular notch called the suprascapula notch, the lateral side of which is formed by the base of the coracoid process. This notch allows the suprascapular nerve to pass above/through the scapula bone protected by the surrounding bone structure. The lateral part of the superior border (adjacent to the suprascapula notch) is one surface of attachment of the omohyoid muscle, whose point of insertion is the tendons and fascia attached to the clavicle (bone) and first rib. |