how do muscles of the back function
Click to read more below. The trapezius is one of the major muscles of the back and is responsible for moving, rotating, and stabilizing the scapula (shoulder blade) and extending the head at the neck. It is a wide, flat, superficial muscle that covers most of the upper back and the posterior of the neck.Like most other muscles, there are two trapezius muscles â a left and a right trapezius â that are symmetrical and meet at the vertebral column.he trapezius is one of the major muscles of the back and is responsible for moving, rotating, and stabilizing the scapula (shoulder blade) and extending the head at the neck.