Your neck, also known as the cervical spine, is a complex series of bones, discs, muscles, nerves, and ligaments. There are seven bones, each called a cervical vertebra, that are stacked upon one another.
These cervical vertebrae are specially shaped and configured to allow for maximum motion while supporting your skull and protecting your spinal cord, neighboring blood vessels, and nerves.
Anatomy
The seven cervical vertebrae can be divided into two groups: atypical vertebrae and typical vertebrae.
Atypical Vertebrae
The atypical vertebrae are cervical level one and two (C1 and C2). Cervical one is also called the atlas, as it supports the weight of your skull. Cervical two is called the axis, as it is the one essential for allowing rotation to occur in the cervical spine. Both the atlas and axis are small, flat vertebrae.
The atlas at cervical level one is a flat, ring-shaped vertebra. It does not have a vertebral body. The flat area on its superior surface supports your skull. Most of the flexion and extension that occurs during head nodding occurs at the articulation between your skull and the atlas.
Cervical level two is called the axis, and has a large bony protrusion called the dens or odontoid process. This bony odontoid process passes up through the ring-like atlas vertebrae and forms the atlantoaxial joint. This is where about 50% to 60% of cervical rotation occurs. Small ligaments attach the odontoid process to the atlas.
Typical Cervical Vertebrae
Cervical level three through six are considered typical cervical vertebra and are similar in shape and function. Each vertebra has a vertebral body, arch, and facet joint (one on each side of the vertebra).
The vertebral body is the large cylindrical bone towards the front of the vertebra. It supports the load of the skull and vertebrae above it. The intervertebral disc attaches to the vertebral body.
The arch of each vertebra is made up of two pedicles and two laminae. The pedicles arise from the vertebral body and wrap around the back to the laminae.
The laminae on each side of the vertebra attach in the back to form the spinous process. The arch forms the ring of bone that protects your spinal cord. The transverse process, a small bony prominence on each side of the vertebra, has a hole in it that houses the ascending vertebral arteries.
The facet joints of each cervical vertebra provide an articulation point for the bone above and below it. These joints are like other joints in the body in that they are lined with smooth cartilage and allow for pain-free gliding and sliding between two bones.
The seventh cervical vertebra is slightly different from cervical levels three through six. This bone has a larger surface area on its body to attach to the thoracic vertebra below it, forming the cervicothoracic junction.
There is no hole in the transverse processes of this vertebra for the vertebral artery as in the vertebrae above it. Cervical seven also has the largest spinous process in the cervical spine; it's the bump that you can easily see and palpate when you bend your neck forward.
There should be a slight forward curve in your neck when the seven cervical vertebrae are stacked upon one another. This curve is called lordosis. Loss of the lordosis may signify spinal muscle spasm or problems with the discs between each cervical vertebra.
Function
The main function of the cervical vertebrae is to protect your spinal cord. The seven bones stacked upon one another form a bony tunnel for your spinal cord to travel through.
The articulation of two bones creates a small hole, called a foramen, through which your peripheral spinal nerves travel. These nerves traverse through your shoulder and down to your arm and hand.
The cervical vertebrae also work to allow for maximal motion to occur. The joints of the vertebra allow for flexion, extension, and side bending.
The special shape of the first and second cervical vertebrae supports the weight of your skull and allows for significant rotation to happen in your upper cervical spine. This allows you to move your head freely in many different directions.
Another important function of your cervical vertebrae is to protect blood vessels that provide circulation to your brain. There is a small hole on each side of the cervical vertebrae, and through this hole passes the vertebral basilar artery. The bony cervical vertebrae protect this vital blood vessel.
The cervical vertebrae also provide an attachment point for many muscles in your shoulders and trunk.
The Anatomy of the Sternocleidomastoid Muscle
Associated Conditions
The cervical vertebrae protect your spinal cord and blood vessels and allow for quite a bit of motion to occur. But they are also subjected to possible injury that may cause pain or loss of mobility in your neck. Problems that may occur with cervical vertebrae and cause neck pain may include:
- Cervical vertebra fracture
- Degenerative disc disease
- Cervical stenosis
- Herniated disc
- Cervical arthritis
Each of these conditions may cause pain in your neck, shoulder, or arms. You may also experience tightness in muscles around your neck and shoulders or a loss of movement in one or more motions in your neck.
Cervical stenosis may cause a serious condition called cervical myelopathy where your cervical vertebra presses upon your spinal cord. This may cause pain, tingling in your arms or legs, or loss of balance while walking.
This is considered a medical emergency, and rapid decompression of your spinal cord via surgery is usually recommended. Likewise, a fracture of a cervical vertebra is considered dangerous, as this may lead to injury to your spinal cord.
If you are experiencing neck pain or difficulty moving your head, visit your physician right away. They can examine you and diagnose your condition. Then you can begin regaining normal pain-free mobility.
Effects of Uncovertebral Joint Hypertrophy
Rehabilitation
If you have neck pain, arm pain coming from your neck, or loss of cervical motion, you may benefit from working with a physical therapist to regain pain-free mobility. Most often, neck conditions respond well to conservative treatments, allowing you to quickly return to your previous level of pain-free function.
Various treatments for your neck may include:
- Exercise: Exercises like cervical rotation, side bending, or retraction may be performed to improve the overall range of motion in your neck.
- Postural instruction: A forward head posture may place increased stress and strain on your neck, leading to pain or limited mobility.
- Heat: Heat is often used for neck pain to decrease muscle spasms and improve circulation to the muscles of your neck.
- Cervical traction: Traction may be used to decrease pain and pressure between cervical joints and discs.
- Massage: Massage is used to increase blood flow and decrease pain in muscles around your cervical spine.
- Electrical stimulation: Electrical stimulation, often in the form of transcutaneous electrical neuromuscular stimulation (TENS), may be used to decrease pain and increase local blood flow.
Most episodes of neck pain or cervical radiculopathy resolve within a few weeks. If your pain persists, visit your physician. You may require more invasive treatments such as spinal injections or surgery.
If your neck pain has come on as the result of trauma, you should seek medical care right away. An X-ray can be taken to assess bone integrity, and a magnetic resonance imaging (MRI) test can check the status of the soft tissue around your neck.
If trauma has occurred, you may be required to immobilize your neck with a cervical collar while things are healing. Once healed, you may benefit from the treatments above to regain normal mobility in your cervical spine.