Final answer:
The upper body musculature can be divided into four groups involved in the stabilization and movement of the pectoral girdle and limbs. The pectoral girdle serves as a foundation for arm movement. Muscles of the pectoral girdle are a mix of anterior and posterior muscles that provide motion and stability.
Step-by-step explanation:
The musculature of the upper body is a complex system that can generally be divided into four main groups: muscles that stabilize and position the pectoral girdle, muscles that move the arm, muscles that move the forearm, and muscles that move the wrists, hands, and fingers. The pectoral girdle , which includes the clavicle, scapula, and proximal end of the humerus, acts as a stable base for the movement of the arm.
The muscles that stabilize and position the pectoral girdle include both anterior muscles such as the subclavius, pectoralis minor, serratus anterior, and posterior muscles like the trapezius, rhomboid major, and rhomboid minor. These muscular groups allow a wide range of motion and stability, necessary for the diverse movements of the upper limbs .