Clavicle muscles are muscles that attach to the clavicle (collarbone). These muscles play crucial roles in shoulder movement and stability.
The clavicle serves as an attachment point for several important muscles:
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Trapezius Muscle: The trapezius muscle attaches along the posterior surface of the lateral third of the clavicle. This muscle helps with scapular (shoulder blade) movement, including elevation, depression, retraction, and rotation.
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Deltoid Muscle: The anterior portion of the deltoid muscle attaches to the periosteum (outer covering) at the anterior surface of the clavicle. The deltoid muscle is responsible for shoulder abduction (raising the arm away from the body), flexion, and internal rotation.
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Sternocleidomastoid (SCM) Muscle: The sternocleidomastoid muscle has one of its origins on the superior aspect of the medial clavicle. It is a major muscle involved in neck flexion, rotation, and lateral flexion, as well as assisting in respiration.
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Pectoralis Major Muscle: The clavicular head of the pectoralis major muscle originates from the anterior surface of the medial half of the clavicle. It contributes to shoulder adduction (bringing the arm towards the body), internal rotation, and flexion.
Here's a table summarizing the clavicle muscles:
| Muscle | Attachment Point on Clavicle | Function |
|---|---|---|
| Trapezius | Posterior surface of the lateral third | Scapular elevation, depression, retraction, and rotation |
| Deltoid | Anterior surface of the clavicle (anterior portion) | Shoulder abduction, flexion, internal rotation |
| Sternocleidomastoid | Superior aspect of the medial clavicle | Neck flexion, rotation, lateral flexion; assists in respiration |
| Pectoralis Major (clavicular head) | Anterior surface of the medial half | Shoulder adduction, internal rotation, flexion |
In summary, the muscles that attach to the clavicle are the trapezius, deltoid, sternocleidomastoid, and the clavicular head of the pectoralis major. They contribute significantly to shoulder and neck function.
