Flesh & Bone: Supinator & Scapula

The Supinator: the Supinator is a key muscle of supination or bringing the palm face up. It originates on the lateral epicondyle of the humerus, the supinator crest of the ulna, the radial colateral ligament and the annular ligament. It arises fan-like from two planes: the deep plane is muscular and the superfiscial is tendonous. Between these two planes lies the radial nerve; its deep branch being the innervating nerve. it inserts onto the lateral proximal radial shaft, specifically the radial tuberosity along the oblique line of the radius. It is this oblique line of pull that allows it to perform its action. Its artery is the recurrent radial artery.

Scapula: Simply put the Scapula is the bone that connects the humerus to the calvicle, though the scapula is anything but simple. It is quite possibly the most ingeniously designes bone int he human body. In a larger more systemic picture the scapula forms the posterior portion of the shoulder girdle, the mechanism that mobilizes the arm & the "shoulder". The Scapula can be broken down into many bony landmarks.

The spine is the prominent or palpable part of bone, which crosses obliquely separating the supra- from the infraspinatous fossa. It begins at the medial or vertical border where at the insertion of the lower part of the Trapezius glides, and, gradually becomes more elevated, ending in the acromion, which overhangs the shoulder-joint.

The coracoid process, from the Greek "crow" which indicates it's beak-like quality, is a thick curved process attached by a broad base to the upper part of the neck of the scapula. It runs at first upward and medial; then, becoming smaller, it changes its direction, and projects forward and lateral. It is palpable in the deltopectoral groove, it is the attachment site for several muscles and ligaments that help to stabilize the shoulder.
The Acromion from the Greek Akros or "highest" forms the summit of the shoulder as well as the articulation with the  clavicle forming the acromioclavicular joint with the corresponding ligaments.
There are also the divisions by fossa: sub-scapular, supraspinatous fossa & infraspinatious fossa.
This is by no means an exhaustive list of the divisions of the scapula but a perusal of its most prominent features.