Clavicle

The clavicle, or collarbone, is a long bone with a distinctive S-shaped curve. It connects the sternum to the scapula and is the only horizontally positioned long bone in the human body. Its subcutaneous location makes it easily palpable along its entire length.

Key Features

Function

The clavicle acts as a strut to maintain the position of the scapula and facilitates a wide range of shoulder movements.

Structure

1. Shaft (Body): The cylindrical middle part of the clavicle.

• Medial two-thirds: Rounded or prismatic, with a forward-directed convexity.

• Lateral third: Flattened from above downward, with a forward-directed concavity.

2. Medial (sternal) end: Articulates with the manubrium of the sternum at the sternoclavicular joint.

3. Lateral (acromial) end: Articulates with the acromion of the scapula at the acromioclavicular joint.

Protective Role

The clavicle protects vital neurovascular structures located beneath it, including:

• The subclavian vein, positioned medially and inferiorly, closest to the sternal end.

• The subclavian artery, located slightly lateral and deeper.

• The brachial plexus cords, positioned further laterally, provide innervation to the upper limb.