Sternoclavicular articulation. Anterior view.
Sternoclavicular articulation visible near center but not labeled.
The sternoclavicular articulation is structurally classed as a synovial double-plane joint and functionally classed as a diarthrotic joint. It is composed of two portions separated by an articular disc which is made from fibrocartilage. The parts entering into its formation are the sternal end of the clavicle, the upper and lateral part of the manubrium sterni (clavicular notch 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 sternoclavicular joint allows movement of the clavicle in three planes, predominantly in the anteroposterior & vertical planes, although some rotation also occurs. Muscles don't directly act on this joint, although almost all actions of the shoulder girdle or the scapula will cause some motion at this articulation.
The unique double-hinged articular disk found at the junction of the clavicular head and manubrium allows for movement between the clavicle and the disk during elevation and depression of the scapula. This disk also allows motion between the sternum (manubrium) and itself during protraction and retraction of the scapula.
- Anterior sternoclavicular ligament
- Articular capsule
- Articular disk
- Costoclavicular ligament
- Interclavicular ligament
- Posterior sternoclavicular ligament
Trauma may result in sternoclavicular joint dislocation. Posterior dislocation puts the mediastinal structures at risk. Spontaneous subluxation also occurs sometimes. In SAPHO syndrome there may be arthropathy of the sternoclavicular joint. Septic arthritis may rarely affect the sternoclavicular joint.
- Acromioclavicular joint
- Shoulder girdle (Pectoral girdle)
- Glenohumeral joint (Shoulder joint)
- Lippert, Lynn. Clinical Kinesiology and Anatomy, 4th edition; pg.95-96.
|Wikimedia Commons has media related to Sternoclavicular joint.|
- 429523022 at GPnotebook
- Overview at ouhsc.edu
- Anatomy figure: 10:01-08 at Human Anatomy Online, SUNY Downstate Medical Center