Claviculaende

Claviculaende refers to the ends of the clavicle, the two extremities of the S-shaped bone of the shoulder girdle. The clavicle connects the axial skeleton to the upper limb, acting as a strut that helps position the shoulder and protects underlying neurovascular structures. The ends are the medial, or sternal, end and the lateral, or acromial, end, each with distinct articulations and landmarks.

Medial end (sternal end): The medial end is rounded and articulates with the manubrium of the sternum at the sternoclavicular joint. It forms a paired surface for this joint and possesses features on the inferior aspect that relate to ligament attachments around the joint. The sternoclavicular end is commonly described as relatively robust, designed to withstand forces transmitted from the trunk to the upper limb.

Lateral end (acromial end): The lateral end is flattened and articulates with the acromion process of the scapula, forming the acromioclavicular joint. On the inferior surface near the lateral end lie the conoid tubercle and the trapezoid line, which serve as attachment points for the coracoclavicular ligaments (conoid and trapezoid) that stabilize the acromioclavicular joint. The lateral end is broader than the medial end and adapts to its joint contact.

Development and variation: Ossification of the clavicle begins in fetal life by intramembranous formation. Two secondary ossification centers appear late in adolescence at the ends and typically fuse with the shaft in adulthood, though timing can vary among individuals.

Clinical significance: End fractures (of the medial or lateral clavicle) are less common than midshaft fractures but can occur and may risk injury to nearby structures or joints. Imaging with X-ray is standard, with CT used when sternoclavicular or acromioclavicular injuries require detailed assessment.