The pectoral and pelvic girdles are both sturdy sockets for limb articulation. The pectoral girdle is larger but does not bear much weight, while the pelvic girdle is lightweight but weight-bearing.
The pectoral girdle includes the clavicles and scapulae, and it connects the upper arms to the axial skeleton. There is no anatomical joint between the scapula and the rib cage, but rather a connection made up of muscle and ligament. This allows for a greater range of mobility and flexibility. The pelvic girdle consists of the hip bones, the sacrum and the coccyx. The pelvis has four points of articulation, which cause it to have less mobility than the pectoral girdle.