The medullary cavity (medulla, innermost part) is the central cavity of bone shafts where red bone marrow and/or yellow bone marrow (adipose tissue) is stored; hence, the medullary cavity is also known as the marrow cavity.

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ANATOMY AND FUNCTION 

Fractures of the clavicle are common injuries accounting for between 2.6 and 4% of adult fractures and 35% of injuries to the shoulder girdle [1-3]. Early reports of clavicle fractures date back to Hippocrates [4], who noted that “when a fractured clavicle is fairly broken across it is more easily treated, but when broken obliquely it is more difficult to manage”.