This document provides information about the clavicle bone, including its location and articulations. It discusses the two main joints of the clavicle - the acromioclavicular joint and sternoclavicular joint. Landmarks on the superior and inferior surfaces of the clavicle are described, including the acromial facet, sternal facet, costal tuberosity, and conoid tubercle. Common fractures of the clavicle from injuries or falls are also mentioned.

1. CLAVICLEANAND GURMAITA

2. INTRODUCTION
The clavicle is an elongated, S-shaped bone that rests
horizontally at the sternum across the upper part of the
ribcage, and the acromial end of the scapula.
This bone is an important part of the skeletal system since it plays
an essential role in everyday functional movement, serving as the
connection between the axial skeleton and the pectoral girdle.
The clavicle is able to act as a brace for the shoulder,
allowing weight to be transferred from the upper limbs to the
axial skeleton.

4. ARTICULATIONS
1.Acromioclavicular joint
The first is the acromioclavicular joint, which is formed by
the acromial end of the clavicle and the acromion of the
scapula respectively.
It enables slight gliding movement about the shoulder
region.
The synovial joint is surrounded by a capsule of articular
cartilage filled with intra-articular synovium.

6. 2. Sternoclavicular joint
 The sternoclavicular joint, which is formed by the sternal
end of the clavicle and the manubrium of the sternum.
 This synovial joint is important as it anchors the clavicle and
scapula to the axial skeleton.
the joint enables a variety of limited movements of the arm,
including:
• protraction and retraction
• depression and elevation
• slight rotation

8. BONE LANDMARKS
Extremities
The orientation of the clavicle can be distinguished by its
ends: a broad, flat acromial end (referred to as the lateral
third); and a round pyramidal-like sternal end (referred to as
the medial two-thirds). Each end has unique bony
landmarks, depending whether the superior or inferior
surface of the bone is viewed.

9. Superior surface
The superior surface of the clavicle has a smooth
appearance. The acromial facet can be seen at the far
posterior edge of the acromial end. It appears as a small
flattened oval surface and enables the clavicle to articulate
about the acromion of the scapula in the acromioclavicular
joint.
The acromial facet is a small, flattened, oval surface
directed obliquely downward, for articulation of clavicle with
the acromion of the scapula.

11. Inferior surface
In contrast, the inferior surface of the clavicle is quite rough and has
many prominent lines, indicating sites where muscle and ligaments
may attach to the bone. These can be divided into three bony
landmarks:
• The sternal facet, found far at the edge of the sternal end. It is shaped
like a triangle, with a posterior tip and an anterior base, and forms the
sternoclavicular joint.
• The costal tuberosity, located at the sternal end of the bone. It is
distinguished as a broad rough surface over 2 cm in length, and is the
site where costoclavicular ligament attaches.
• The conoid tubercle, which is found more laterally towards the acromial
end. It appears as a rough eminence found where the flat portion of the
clavicle meets the tip of the pyramidal sternal end. This feature acts as
the site where the conoid ligament attaches.

12. sternal facet

13. FRACTURES
Fractures are common pathologies that occur in the clavicle,
usually resulting from injury or trauma. This can include car
accidents or contact sports, where the clavicle is exposed to strong
impacts that can exert compressive forces on the bone.
Alternatively, falls can trigger a clavicle fracture, such as falling
directly on one’s shoulder, or falling with an outstretched arm.
Symptoms of a clavicle fracture include:
• Severe pain upon movements of the shoulder and arm
• Swelling, bruising and tenderness over the fractured area
• Sagging of the shoulder in an anterior and inferior direction

16. THE END