Scapula
"Scapula" is the technical name for the shoulder blade. It is a flat,
triangular bone that lies over the back of the upper ribs. The rear
surface can be felt under the skin. It serves as an attachment for
some of the muscles and tendons of the arm, neck, chest and back and
aids in the movements of the arm and shoulder. It is well padded with
muscle so that great force is required to fracture it.
The back surface of each scapula is divided into unequal portions by a
"spine." This spine leads to a "head," which bears two processes - the
"acromion process" that forms the tip of the shoulder and a "coracoid
process" that curves forward and down below the clavicle (collarbone).
The acromion process joins a clavicle and provides attachments for muscles
of the arm and chest muscles. The acromion is a bony prominence at the top
of the shoulder blade. On the head of the scapula, between the processes
mentioned above, is a depression called the "glenoid cavity." It joins
with the head of the upper arm bone (humerus).
