Appendicular skeleton

The appendicular skeleton is the bones of the limbs together with their girdles. Each limb has 30 bones.

Fore limb: humerus, radius and ulna, 8 carpals (wrist), 5 metacarpals (palm) and 14 phalanges (digits).

Hind limb: femur (the longest bone), tibia and fibula, 7 tarsals (ankle), 5 metatarsals and 14 phalanges. A cup-shaped patella, the knee cap, covers the knee on its ventral side.

The pectoral and pelvic girdles join the upper and lower limbs to the axial skeleton; each girdle has two halves.

Each half of the pectoral girdle has a clavicle and a scapula. The scapula is a large triangular flat bone on the dorsal thorax between the second and seventh ribs.

The scapula's raised ridge, the spine, ends in a flat expanded acromion, with which the clavicle articulates. Just below the acromion lies the glenoid cavity; the humerus head fits into it, making the shoulder joint.

The clavicle, or collar bone, is a long slender bone with two curves.

The pelvic girdle has two coxal bones, each formed by fusion of the ilium, ischium and pubis. At the point of fusion is the acetabulum, the cavity into which the thigh bone fits.

The two halves of the pelvic girdle meet ventrally at the pubic symphysis, which contains fibrous cartilage.