Muscles involving the pectoral girdle
MUSCLES INVOLVING THE PECTORAL GIRDLE ANATOMYThe pectoral girdle refers to the area where the shoulder joins the axial skeleton at the site of the sternoclavicular joint. The muscles involved are required to exceed the expectations of strength and flexibility in the area, and are formed much like a strong strap holding the shoulder to the chest.
The muscles responsible for motion involving the brachium have origination points along the scapula. However, when normal motion of the brachial area occurs, the scapula can not risk additional movement and must rely on a muscular structure to hold it in place.
MUSCLES INVOLVING THE PECTORAL GIRDLE STRUCTUREThe muscles involved in the movements of the pectoral girdle are segregated into two distinctive groups. The anterior and posterior muscle groups all originate on the axial skeleton. The pectoralis minor, the subclavius, and the serratus are the anterior division of the muscles involving the pectoral girdle.
This leaves the levator scapulae, the rhomboideus, and the trapezius muscles, which of course are designated as the posterior muscles of the pectoral girdle.
The muscles of the pectoral girdle are designed that not a single muscle can initiate a specific action without the assistance of at least one other muscle. Actions within the pelvic girdle usually require several synergetic muscle contractions.