The sternoclavicular articulation is a double arthrodial joint composed of two portions separated by an articular disc. The parts entering into its formation are the sternal end of the clavicle, the upper and lateral part of the manubrium sterni, and the cartilage of the first rib, visible from the outside as the suprasternal notch. The articular surface of the clavicle is much larger than that of the sternum, and is invested with a layer of cartilage, which is considerably thicker than that on the latter bone. The ligaments of this joint are: Articular capsule Anterior sternoclavicular ligament Posterior sternoclavicular ligament Interclavicular ligament Costoclavicular ligament Articular disk [WP,unvetted].