Announcing the next body part to pick a bone 🦴 with: the SPINE.🚶♀️🚶♂️
Specifically, continuing BeneFIT’s Anatomy Blog Series, this month’s post will discuss the anatomical features of a HUMAN CERVICAL SPINE!🚶♂️
Our cervical spine consists of seven vertebrae. Each vertebra is named by its location in order from top (C1 or first vertebra) to bottom (C7 or seventh vertebra).
The C1 vertebra, which holds the skull, is named the Atlas after the mythological titan Atlas who was said to have held the Earth on his shoulders.
Similar to the C1 vertebra, the C2 vertebra is named Axis because it provides the axis which the skull and atlas rotate when the head is moved side to side or up and down.
There are six main muscles that are located around the cervical spine:
Levator scapulae: The levator scapulae muscle is to the top four cervical vertebrae (C1 to C4). It runs down the side of the neck and attaches at the top of the shoulder blade (scap ula). This muscle helps with lifting the shoulder blade, bending the neck to the side, and rotating the head.
Sternocleidomastoid (SCM): The SCM is attached to a small bone behind the ear (mastoid process). It travels down the front of the neck and attaches at both the sternum and collarbone. The SCM allows the head to be rotated to the side or the chin tilted upward.
Trapezius: The trapezius muscle is a large muscle that spans from the base of the skull, down into the lower thoracic spine (mid back) and out to the shoulder blade. The trapezius helps extend the head upward or neck backward, rotating/turning the head, or lifting the shoulder blade.
Erector spinae: In the cervical spine, the erector spinae muscles play key roles in supporting posture, rotating the neck, and extending the neck backward.
Deep Cervical Flexors: These muscles are comprised of the longus capitus and longus colli muscles which run down the front of the cervical spine. The deep cervical flexor muscles help flex the neck forward as well as stabilize the cervical spine.
Sub-occipitals: This group consists of 4 pairs of small muscles. The sub-occipital muscles connect the top of the cervical spine to the base of the skull. The sub-occipitals help with extending the head and rotating the head.
The cervical spine contains discs, as does the rest of the spine. There are two main components to the cervical discs. The Outer Layer and the Inner Layer.
The Outer Layer is the exterior. It is called the annulus fibrosis and is made up of collagen fibers which protect the core of the discs.
The Inner Layer or the center is called the nucleus pulposus. This layer is a soft jelly-like substance that allows the disc to be flexible and provide cushion.