Acromioclavicular Joint

 ACROMIOCLAVICULAR JOINT

Articulating Surface and Type of Joint

This joint is formed by the lateral end of the clavicle and the acromion of the scapula. It is a planar joint.

Ligaments

The major ligaments are the superior and inferioracromioclavicular ligaments and the coracoclavic-ular ligaments (see Figure 3.40). The latter, althoughsituated away from the joint, provides joint stability. The trapezoid and conoid ligaments are important for preventing excessive lateral and superior move-ments of the clavicle. They also help suspend the scapula from the clavicle.

Movements, Range of Motion, and Muscles

Little movement takes place in this joint.


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