Pectoral girdle

Shoulder girdle
Human shoulder girdle
Details
Identifiers
Latin	cingulum pectorale
TA	A01.1.00.020
FMA	23217
Anatomical terms of bone []

The shoulder girdle or pectoral girdle is the set of bones which connects the arm to the axial skeleton on each side. In humans it consists of the clavicle and scapula; in those species with three bones in the shoulder, it consists of the clavicle, scapula, and coracoid. Some mammalian species (such as the dog and the horse) have only the scapula.

The pectoral girdles are to the upper limbs as the pelvic girdle is to the lower limbs; the girdles are the parts of the appendicular skeleton that anchor the appendages to the axial skeleton.

In humans, the only true anatomical joints between the shoulder girdle and the axial skeleton are the sternoclavicular joints on each side. No anatomical joint exists between each scapula and the rib cage; instead the muscular connection or physiological joint between the two permits great mobility of the shoulder girdle compared to the compact pelvic girdle; because the upper limb is not usually involved in weight bearing, its stability has been sacrificed in exchange for greater mobility. In those species having only the scapula, no joint exists between the forelimb and the thorax, the only attachment being muscular.

The shoulder girdle is a complex of five joints that can be divided into two groups. Three of these joints are true anatomical joints while two are physiological ("false") joints. Within each group, the joints are mechanically linked so that both groups simultaneously contribute to the different movements of the shoulder to variable degrees.