Clavicle. The clavicles, or collarbones, are a pair of long bones that connect the scapula to the sternum. The name clavicle comes from the Latin word for “little key” and describes the shape of the clavicle as an old-fashioned skeleton key. The clavicle is one of the most commonly broken bones in the human body.

clavicle: [noun] a bone of the shoulder girdle typically serving to link the scapula and sternum — called also#R##N# collarbone.

The AC joint is the articulation between the acromial end of clavicle and the clavicular facet of the acromion of scapula. The clavicular articular surface is oval and slightly convex while the acromial surface is accordingly concave. Both articular surfaces are covered with fibrocartilage .