Final answer:
The muscles surrounding the pectoral girdle, such as the trapezius, rhomboid major/minor, serratus anterior, and subclavius, are responsible for stabilizing and positioning the pectoral girdle, consisting of the clavicle and scapula.
Step-by-step explanation:
The primary type of tissues responsible for stabilizing, positioning, and bracing the pectoral girdle are the muscles that surround and attach to it. These muscles are crucial for providing a stable base for upper limb movement and transfer the force generated by muscles acting on the upper limb to the thorax.
The pectoral girdle itself consists of two bones: the clavicle, which is anterior, and the scapula, which is posterior. The clavicle is unique because it is the only long bone that lies horizontally in the body.
The muscles specifically involved in positioning the pectoral girdle include the trapezius, rhomboid major, and rhomboid minor in the back, and the serratus anterior and subclavius in the front.
These muscles work in coordination to stabilize and move the scapula, providing the necessary support and mobility for actions such as lifting, pushing, and pulling.
The coordination of these muscles not only stabilizes the pectoral girdle but also allows for the extensive mobility of the shoulder and upper limb. This muscular support is essential for the proper functioning and physical activities involving the arms and upper body.