Final answer:
The muscles that stabilize the scapula include the anterior muscles (subclavius, pectoralis minor, serratus anterior) and the posterior muscles (trapezius, levator scapulae, rhomboid major, rhomboid minor), all of which work to move and secure the scapula.
Step-by-step explanation:
All five of the muscles that stabilize the scapula have the action of either moving the scapula itself or the humerus bone of the arm. These muscles are grouped into anterior and posterior muscles. The anterior muscles include the subclavius, pectoralis minor, and serratus anterior, which stabilize the scapula by moving it in relation to the ribcage. The posterior muscles include the trapezius, levator scapulae, rhomboid major, and rhomboid minor, which also stabilize the scapula by moving it medially when contracted or by pulling the shoulder and upper limb posteriorly. Collectively, these muscles help to secure the scapula, providing a stable base for the movement of the arm.