Question

Is this statement true The upper trap muscles have two main sections: the descending (nuchal) fibers and the transverse (acromial and clavicular) fibers. The acromial fibers of the upper traps attatch to the lateral aspect of the scapula, while the clavicular fibers attatch to the lateral third of the clavicle. So while the acromial fibers of the upper traps do attatch directly to the scapula the clavicular fibers attatch to the clavicle and not directly to the scapula. However, the action of both the acromial and clavicular fibers of the upper traps can indirectly contribute to scapular elevation and upward rotation. During scapular elevation, both the acromial and clavicular fibers of the upper traps muscles contract to pull the scapula upward and rotate it slightly upward aswell. This upward rotation of the scapula is important for the proper alignment and function of the shoulder joint.

Answer 1

The upper trapezius muscles have descending and transverse fibers that contribute to the elevation and rotation of the scapula, essential for the shoulder joint's function and allowing for upper limb abduction.

Step-by-step explanation:

The statement that the upper trapezius muscles have descending (nuchal) fibers and transverse (acromial and clavicular) fibers is correct. The acromial fibers attach to the lateral aspect of the scapula, contributing to scapular elevation and rotation, which is essential for proper alignment and function of the shoulder joint. The clavicular fibers attach to the lateral third of the clavicle, and although they do not attach directly to the scapula, they contribute to scapular motion indirectly. Both fiber groups cooperate during scapular elevation, assisting in superior rotation necessary for abduction of the upper limb. The shoulder muscles, including the deltoid, subscapularis, supraspinatus, and infraspinatus, originate on the scapula and coordinate to facilitate various arm movements. Additionally, the accessory nerve innervates the trapezius and sternocleidomastoid muscles, playing a role in movements of the head, trunk, and shoulders.