The subclavius muscle is located between the clavicle (collarbone) and the first rib.
Detailed Location and Function
The subclavius muscle is a small, triangular muscle situated deep in the shoulder region. Its precise location and attachments contribute to its functions:
- Origin: The subclavius muscle originates from the junction of the first rib and its costal cartilage.
- Insertion: It inserts onto the inferior (under) surface of the clavicle, near the middle third of the bone.
This positioning allows the subclavius to perform the following functions:
- Depression of the Clavicle: It helps to pull the clavicle downward.
- Stabilization of the Sternoclavicular Joint: It provides stability to the joint where the clavicle meets the sternum (breastbone).
- Protection of Underlying Neurovascular Structures: It helps protect the subclavian artery and vein, as well as the brachial plexus, which pass underneath it.
Anatomical Relationships
The subclavius muscle is part of the anterior axioappendicular muscles, which also include the pectoralis major and pectoralis minor muscles. These muscles contribute to the anterior wall of the axilla (armpit).
The relationship of the subclavius to other structures is important clinically. For example, a fracture of the clavicle can sometimes injure the subclavius muscle or the underlying subclavian vessels.
