sternoklavikulære

The sternoklavikulære led, or sternoclavicular joints, are the articulations between the manubrium of the sternum and the medial ends of the clavicles. They are the only true joints linking the upper limbs to the axial skeleton. The joint is a synovial saddle-type articulation that includes an articular disc, dividing the joint cavity into two spaces and enhancing stability and congruence of the articulating surfaces.

Anatomy and ligaments: The joint is encapsulated and reinforced by several ligaments, including the anterior and posterior sternoclavicular ligaments, the interclavicular ligament, and the costoclavicular ligament. The interposed articular disc helps absorb impact and improves joint congruence. The capsule and ligaments together permit multi-axial movement while limiting excessive motion.

Function: The sternoclavicular joint allows elevation and depression of the clavicle, protraction and retraction, and posterior rotation of the clavicle during arm elevation. These motions contribute to the overall movement of the shoulder girdle and the ability to raise the arm above shoulder level. The joint also helps transmit axial load from the upper limb to the trunk.

Clinical significance: Injuries to the sternoclavicular joint are relatively uncommon but can be serious. Dislocations, especially posterior dislocations, can threaten mediastinal structures. Osteoarthritis and inflammatory arthritis may affect the joint. Imaging, including dedicated X-ray views or CT, is used for assessment. Treatment ranges from immobilization and physical therapy to surgical stabilization in cases of recurrent instability or irreducible dislocations.