Corpus: Acromioclavicular ligament
1. Definition
The acromioclavicular ligament is a band that reinforces the acromioclavicular joint. It extends from the acromion of the scapula to the clavicle.
2. Anatomy
There are two distinct components of the ligament:
- superior acromioclavicular ligament
- inferior acromioclavicular ligament
2.1. Superior Acromioclavicular Ligament
The superior acromioclavicular ligament is a square-shaped band that reinforces the cranial part of the joint capsule of the acromioclavicular joint. It runs from the upper edge of the lateral end of the clavicle to the opposite upper side of the acromion. It consists of parallel fibers that radiate into the aponeurosis of the trapezius muscle and the deltoid muscle.
2.2. Inferior Acromioclavicular Ligament
The inferior acromioclavicular ligament is thinner than its cranial counterpart. It forms the caudal part of the joint capsule and is closely associated with the tendon of the supraspinatus muscle.