Page 69 - Alaska A & P Primer

Muscles of the Neck and Back
The large, complex muscles of the neck and back move the head, shoulders, and vertebral column.
The superficial and deep muscles of the neck are responsible for moving the head, cervical vertebrae, and scapulas.
The head, attached to the top of the vertebral column, is balanced, moved, and rotated by the neck muscles. When these muscles act unilaterally, the head rotates. When they con- tract bilaterally, the head flexes or extends. The major muscle that laterally flexes and ro- tates the head is the sternocleidomastoid. In addition, both muscles working together are the flexors of the head. Place your fingers on both sides of the neck and turn your head to the left and to the right. You will feel the movement originate there. This muscle divides the neck into anterior and posterior triangles when viewed from the side.
The posterior muscles of the neck are primarily concerned with head movements, like ex- tension. The back muscles stabilize and move the vertebral column, and are grouped ac- cording to the lengths and direction of the fascicles. The segmental muscles include the interspinales and intertransversarii. Finally, the scalenes include the anterior scalene, mid- dle scalene, and posterior scalene.
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State of Alaska EMS Education Primer - 2016
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