Topic of the Month: Cervical Disc Herniation

By Dianne Mueller, N.D., R.N., C-F.N.P.
Missouri Spine Center

The neck, also known as the cervical spine is made up of seven bones called vertebrae. Together with the surrounding muscles, the neck works to support the head while allowing for motion and protection of the spinal cord and spinal nerves. The bony bump that some people can feel in the back of the neck is called the spinous process. The vertebrae have a hollow center area, in which lies the spinal cord, surrounded by the vertebral body, the facet joints and the spinous process. The vertebrae act as a protective barrier for the soft, delicate tissues of the spinal cord. The spinal cord is the nerve center for the entire spine and starts from the brainstem, travels through the spinal canal and ends in the mid-low back. Small nerve roots branch out of the spinal cord and control sensation and motor functions of the fingers, hands, and arms. The side joints, called facet joints, are small openings that allow the nerve roots to travel out from the spinal cord to the arms.

Between each vertebrae is a cushion, which is made up of cartilage material called the cervical disc. There are discs between each of the vertebrae throughout the entire spine. The discs are the shock absorbers or cushions for the vertebrae. Along with the strong muscles and ligaments, the discs act as a cushion between the bones and allow bending movements of the head and neck. The disc is surrounded by a tough outer covering (annulus) which allows the squishy inner center to stay in place. A disc herniation (sometimes called protrusion) occurs when the middle section (or gelatin) ruptures through its surrounding fibrous band (the outer layer), thus causing pressure on the nerve root that passes by that level. This is called radiculopathy. Rarely, the disc herniation presses on the spinal cord and causes problems with walking and balance. This is called myelopathy.

A herniated cervical disc can be caused from injury, lifting a heavy object, or sudden movement of the neck, but does not need to be caused by trauma. Many people cannot recall a specific injury. The herniated piece of the disc may then pinch or put pressure on a nerve, possibly causing one or more of the following symptoms:

Signs and symptoms of herniated cervical disk;

• Limited movement of the head or neck due to stiffness.
• Neck pain and pain with movement of the head and neck.
• Neck muscle tightness.
• Pain, tingling or numbness in the shoulder, arm or hand (usually worse on one side than the other).
• Weakness in the shoulder, arm or hand.
• Clumsiness of the hand or difficulty with fine motor movements, such as buttoning buttons.

Diagnostic tests

In addition to a thorough history and physical examination, your health care provider may request one or more of the following tests:

Plain X-rays

The first step in the diagnosis of cervical spine problems is generally plain X-rays. The X-rays are done in the radiology department. Generally, it is best to have the X-rays while standing straight up, and looking up and down.

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From left: X-rays bending forward, X-ray bending head back,
and X-ray holding head straight up.

X-ray of the spine showing the Odontoid

MRI (magnetic resonance imaging)

An MRI is one of the most common tests to determine if there is a herniated disc. The test consists of lying on a flat table which moves into the scanning tube. The tube is generally enclosed. There are some scanners that are open, but the closed images are better. The patient is asked to lie very still while the images are being taken. The MRI takes about 20 to 45 minutes to complete. The MRI uses a magnet (instead of X-ray) to take images. An MRI will give detailed images of the soft tissue of the neck, and will show a herniated or protruded disc. It is important to tell the provider if the patient is afraid of small enclosed spaces, as some people will need medication to help them relax. General anesthesia is rarely needed to complete the MRI. People who have a pacemaker, certain types of brain aneurysm clips, shrapnel, or other metal in the body may not be able to have an MRI -- always tell the technician before the test if there is any question of metal in the body.

MRI of the cervical spine showing herniated disc at C4-5.

CT scan

This is a test that is done in the radiology (X-ray) area of the hospital or in an imaging center. The patient lies flat on a hard table that moves into a round, open machine. The machine is completely open, so there is generally no trouble with claustrophobia (or fear of closed places). The patient is asked to lie completely still while the images are being taken. The test takes about 10-30 minutes. In some cases, a dye will need to be injected into an IV in the patient’s arm. This is generally done to better visualize the soft tissues of the neck. The CT scan gives the provider pictures of the bone structure of the neck.

Myelogram/CT is a test that is performed in the CT scanner, much like a regular CT. It is sometimes done to help determine if there is pressure on certain nerves. This test involves injecting a contrast dye into the spinal canal (usually in the low back) and watching how the dye travels through the nerve spaces. If the patient knows they are allergic to contrast dye, it is important to tell the radiologist BEFORE the test begins. In some cases, medications need to be given the day before the test if the person is allergic to dye.

EMG (Electromyogram)

This is a nerve function test to determine what nerves are affected in the arms. The EMG is often helpful to determine if there is nerve damage to one or more nerves that travel from the cervical spine down the arm. The study is generally done by a physiatrist (rehab doctor) or neurologist. This is an outpatient test that is done by inserting very small needles into the muscles that are being tested. There is some degree of discomfort when the needles are placed, and the muscles may be sore the next day. The muscles are stimulated, and monitored for electrical activity. When a nerve does not conduct the electrical impulse properly, a reading is displayed on the monitor. The abnormal signals will help your health care provider to determine the target of the problem.

Treatment options

There are several treatment options for herniated cervical disc. The treatment of choice depends on the physical examination, symptoms and diagnostic test results.

Conservative treatment includes:

• Ice/heat to the muscles of the neck
• Physical therapy for range of motion and strengthening
• Traction may be advised, but should ONLY be performed under the guidance of a trained physical therapist
• Acupuncture - This involves tiny needles into the site of the pain and surrounding areas. This is done by a person who is specially trained in the procedure.
• Exercises - generally guided by a physical therapist to strengthen the neck muscles
• Injections - In some cases, an injection is recommended. This usually consists of a mixture of a numbing medicine and steroid injected into the neck area. This is generally done in the x-ray department by a trained Radiologist or Anesthesiologist.

In some cases, surgery is recommended. This is generally considered after conservative care has failed to relieve the symptoms, if the symptoms worsen, or if there are signs of increasing weakness. The surgeon will explain the exact procedure/risks/benefits during the clinic appointment. The surgery generally consists of a small incision in the front/side of the neck. The disc is removed and a small spacer is placed in the space. A small titanium plate is then attached with tiny screws to the vertebrae above and below the disc space. In most cases, the surgery will take about two to three hours (or more if more than one level is effected), and the hospital stay is generally overnight. A cervical collar is often used after surgery for comfort and to help keep the neck from moving too much after surgery. It is important that the patient DOES NOT SMOKE OR USE TOBACCO products after surgery, as this has been shown to delay or prevent healing. The fusion will generally take about three months for full healing.

Reducing the risk

• Never dive into a shallow pool
• Never dive head-first into a lake or river
• Stop smoking and avoid others who smoke
• Do not chew tobacco
• Perform gentle stretching and bending of your neck.
• Maintain good posture while sitting and walking
• Do not “pop” your neck
• Avoid slouching in a chair or bed
• Adjust your computer screen to eye level to avoid looking down or up for long periods
• Always wear a seat belt while in the car
• Avoid high velocity activities, such as roller coasters
• Place a pillow under your head and neck when lying in bed
• Always lift heavy objects with proper posture, using your legs to do most of the work
• Ask for help if the object is too heavy to lift

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