What is the Acromion?
The acromion is the outermost part of the shoulder blade (scapula). It's a bony projection that forms a joint with the collarbone (clavicle), called the acromioclavicular (AC) joint. This prominent bony structure sits above the glenohumeral joint (the actual shoulder joint where the humerus connects to the scapula).
- Location: The acromion is located on the superior (upper) and lateral (outer) aspect of the scapula. It extends laterally, forming the point of the shoulder.
- Joint Formation: The acromion articulates with the clavicle to form the AC joint, a crucial part of the shoulder girdle.
- Protection: The acromion, along with the coracoid process, extends over the shoulder joint, offering some protection to the underlying structures, including tendons of the rotator cuff.
- Muscle Attachments: Several muscles attach to the acromion, contributing to shoulder movement and stability.
Clinical Significance
The acromion's shape and position play a significant role in shoulder health. Deformities of the acromion, such as a hooked or curved shape, can contribute to conditions like:
- Shoulder Impingement: A curved or hooked acromion can reduce the space under it (subacromial space), leading to impingement of the rotator cuff tendons. https://my.clevelandclinic.org/health/diseases/shoulder-impingement-rotator-cuff-tendinitis
- Acromioclavicular (AC) Joint Problems: The AC joint is susceptible to injury and arthritis, which can cause pain and decreased shoulder function. https://www.hopkinsmedicine.org/health/conditions-and-diseases/ac-joint-problems
- Rotator Cuff Tears: The acromion's shape has been linked to the risk of rotator cuff tears. https://pmc.ncbi.nlm.nih.gov/articles/PMC4799122/
Procedures like acromioplasty (surgical reshaping of the acromion) might be necessary to address acromion-related issues. https://www.orthopaedic-surgery-paris.com/the-surgeries/shoulder-surgery/shoulder-acromioplasty/
