The trapezius is a large superficial muscle on the upper back that is opposed by the serratus anterior. The best exercises for this muscle are shoulder shrugs and upright rows for the upper part, pull-downs for the middle part, and rowing and dead lifts for the bottom part. The following steps will aid in your search for information about this muscle.
Instructions
1. Read up on Greek roots to know that "trapezius" means "figure with four unequal sides." This muscle is roughly a four-sided diamond shape. The upper corner is the neck, the left and right corners are the shoulders and the bottom corner is the twelfth thoracic vertebra.
2. Examine the trapezius to see that it elevates and retracts the scapula. The upper fibers rotate the scapula upwards, the middle fibers retract the scapula and the lower fibers rotate the scapula downwards.
3. Observe how the trapezius originates from the external occipital protuberance along the medial sides of the superior nuchal line, the ligamentum nuchae surrounding the cervical spinous processes and the spinous processes of the first cervical through the twelfth thoracic vertebrae.
4. Look at the insertion of the trapezius into the posterior, lateral one-third of the clavicle, the acromion and the superior spine of the scapula.
5. Research the nervous system to know that the nerve for the trapezius is the spinal accessory (eleventh cranial nerve) for the motor fibers and the ventral ramii of the third and fourth cervical nerves for the sensory fibers. Study the circulatory system to know that the blood supply for the trapezius is the transverse cervical artery.
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