Upper body skeleton. Computer artwork of a glass- effect human female body in side view showing the skeletal structure of the head and torso. Inside the head is the skull (top), comprising the cranium or braincase, facial and jaw bones. The backbone or spinal column runs down the back of the body from the base of the skull to the pelvic bones (not seen). The ribcage (lower centre) is formed of twelve pairs of curved ribs that attach to the spinal column at the back and the sternum or breastbone at the front. The ribcage protects the organs of the thoracic cavity. The large bones behind the ribcage are the scapulae or shoulder blades (only one seen).