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Why does the shoulder drop after a clavicle fracture?
The trapezius muscle is unable to hold the lateral fragment up owing to the weight of the upper limb.
What role does the coracoclavicular ligament play after a clavicle fracture?
The strong coracoclavicular ligament usually prevents dislocation of the acromioclavicular (AC) joint.
What happens to the lateral fragment of the clavicle after a fracture?
The lateral fragment may be depressed and pulled medially by the adductor muscles of the arm such as the pectoralis major
When does the clavicle ossify in the fetus?
The clavicle is the first bone to ossify in the fetus at 6 weeks.
How does the clavicle develop?
It develops in membrane and not in cartilage.
What is the position of the clavicle along its length?
The clavicle is subcutaneous throughout its length.
What forces does the clavicle transmit?
It transmits forces from the arm to the axial skeleton.
How do the medial and lateral thirds of the clavicle differ in shape?
The medial two-thirds are circular in cross-section and curved convex forwards while the lateral third is flat and curved convex backwards.
Where does the clavicle articulate medially?
The clavicle articulates medially with the sternum and 1st costal cartilage at the sternoclavicular joint.
What ligaments attach the clavicle to the first rib and sternum?
The clavicle is attached medially to the 1st rib by strong costoclavicular ligaments and to the sternum by sternoclavicular ligaments.
