The appendicular system is joined and/or fused to the axial system and includes all limbs and the connecting joints and bones. Starting from the top of the body, the appendicular system is composed of four bone groupings: the pectoral girdle, the upper limbs, the pelvic girdle, and the lower limbs. The pectoral girdle is formed by the clavicles, the sternum, and the scapulae. There is a cavity in the scapulae called the glenoid fossa by which the humerus of the upper limb joins to the pectoral girdle. The upper limbs are composed of the humerus (upper arm), the radius & ulna
(forearm), and the carpals (wrist), metacarpals, and phalanges (thumb & fingers).
The pelvic girdle joins with the axial system at the sacrum. It includes the two coxal
(forearm), and the carpals (wrist), metacarpals, and phalanges (thumb & fingers).
The pelvic girdle joins with the axial system at the sacrum. It includes the two coxal