The neck is part of a long flexible column, the spinal column. Also known as the backbone, it extends through most of the body. The neck region contains the cervical spine, which consists of seven bones known as the C1-C7 vertebrae, which are separated by intervertebral discs. These discs allow the spine to freely move. During activity, they also act as shock absorbers.
An arch of bone, which forms a continuous hollow longitudinal space, is attached to each vertebral body’s back. This arch runs through the back’s entire length. This space (spinal canal) is the area through which nerve bundles and the spinal cord pass. Bathed in cerebrospinal fluid (CSF), the spinal cord is surrounded by three protective layers. These are known as the meninges (dura, arachnoid, and pia mater).
At each vertebral level, a pair of spinal nerves exit through small openings. With one to the left and one to the right, these are called the foramina. These nerves serve the skin, muscles, and tissues of the body. Thus, they provide movement and sensation to all parts of the body. The nerves and spinal cord are also supported by strong ligaments and muscles, which are attached to the vertebrae.
CERVICAL STENOSIS
When the spinal canal narrows and compresses the spinal cord, cervical stenosis occurs. This is most commonly caused by aging. In this situation, the discs in the spine, which cushion and separate vertebrae, may dry out and herniate. Accordingly, as the space between the vertebrae shrinks, the discs lose their shock absorbing ability. While this occurs, the ligaments and bones that make up the spine become less pliable, thickening in the process. These changes cause the spinal canal to narrow. Additionally, by contributing to bone spur growth, the degenerative changes associated with cervical stenosis can affect the vertebrae, as these bone spurs compress the nerve roots. As long as symptoms are limited to neck pain, for extended periods of time, mild stenosis can be conservatively treated. However, severe stenosis requires referral to a neurosurgeon.
Poor posture, age, injury, or diseases like arthritis can lead to degeneration of the joints or bones of the cervical spine, causing bone spurs or disc herniation to form. Sudden severe injury to the neck may also contribute to whiplash, vertebral bone or ligament injury, disc herniation, and blood vessel destruction. In extreme cases, permanent paralysis may also occur. Bone spurs or herniated discs may cause a narrowing of the small openings through which spinal nerve roots exit or the spinal cord.
SYMPTOMS OF CERVICAL STENOSIS
Neck pain may be caused by narrowing of the spinal canal, disc degeneration, and arthritis. In rare cases, cancer or meningitis can also cause neck pain.
Symptoms include:
- Arm or neck pain
- Weakness and numbness in the upper extremities hands
- An unsteady gait when walking
- Muscle spasms in the legs
- Loss of coordination in hands, arms, and/or fingers
- Loss of muscle tone in hands and/or arms
- Dropping items or loss of dexterity in hands
WHEN AND HOW TO SEEK MEDICAL CARE
If you have the above listed symptoms or the following, you should consult a neurosurgeon for your neck pain:
- Neck pain after a blow to the neck or head or an injury
- Headache or fever accompanying the neck pain
- Stiff neck prevents touching chin to chest
- Progression of weakness or numbness of legs and/or arms
- No improvement in pain after conservative management
For serious neck problems, a primary care physician and often a specialist like a neurosurgeon should be consulted to make a diagnosis and prescribe treatment. If you experience sudden onset of weakness, the situation may be an emergency. You must seek medical attention at an emergency room, for delaying care may lead to permanent neurological injury.
For more gradual onset of symptoms, which can happen over weeks to months, see your primary care physician for a potential referral to a spine surgeon.
TESTING AND DIAGNOSIS
Based on symptoms, history, a physical examination and results of tests like the following, a neurosurgeon makes a diagnosis.
Some degree of spinal degeneration and arthritis is normal due to aging, so the neurosurgeon must determine if findings on imaging studies correlate to symptoms.
- Computed tomography scan (CAT or CT scan): A diagnostic image, which is created after a computer reads and combines a multitude of thin-cut X-rays. This can show the size and shape of the spinal canal, its contents, and the structures around it, especially bones. The CT scan gives the neurosurgeon information about bone abnormalities. These include osteophytes, bone spurs, presence of fusion, and bone destruction due to tumor or infection.
- Electromyogram and Nerve Conduction Studies (EMG/NCS): These tests measure the electrical impulse along peripheral nerves, nerve roots, and muscle tissue. This will indicate if there is ongoing nerve damage, if the nerves are healing from a past injury, or if there is another site of nerve compression.
- Magnetic resonance imaging (MRI): A diagnostic test, uses powerful magnets and computer technology to produce images of body structures; can show the nerve roots, spinal cord, and surrounding areas as well as disc herniations, enlargement, degeneration, tumors, and infections.
- Myelogram: An x-ray of the spinal canal, which is taken after injection of contrast material into the surrounding cerebrospinal fluid spaces; can show pressure on the nerves or spinal cord due to tumors, herniated discs, and bone spurs.
- X-rays: Can show the bony structures of the spine. This provides information on the presence of arthritis, spinal alignment, fractures, and disc degeneration. X-rays are utilized as a relatively low-risk postoperative imaging study to monitor the spine and any instrumentation placed in the spine.
TREATMENT
Non-surgical treatments
The first approach in patients with common neck pain not involving trauma is nonsurgical treatment. For instance, many patients with cervical disc herniations improve with conservative treatment and time, causing them to not require surgery. Conservative treatment includes time, brief bed rest, medication, reduction of strenuous physical activity, and physical therapy. A doctor may also prescribe medications, which aim to reduce the inflammation or pain and muscle relaxants, which allow time for healing to occur. An injection of corticosteroids into the joints of the epidural space or cervical spine can be used to temporarily relieve pain.
Surgery
The patient may be a candidate for surgery if
- Conservative therapy is not helping
- Presence of progressive neurological symptoms involving legs and/or arms
- Difficulty with walking or balance
- In otherwise good health
Several different surgical procedures can be utilized, the choice of which is influenced by the specifics of each case. For a percentage of patients, spinal instability may require a spinal fusion to be performed. This decision is generally determined prior to surgery. Spinal fusion is an operation designed to create a solid union between two or more vertebrae. Various devices, such as plates or screws, may be used to support unstable areas of the cervical spine and enhance fusion. This procedure may assist in stabilizing and strengthening the spine, thereby helping to alleviate severe and chronic neck pain.
Regardless of which approach is taken, the goals of surgery are the same:
- Decompress the spinal cord and/or nerves
- Improve or maintain stability of the spine
- Correct or maintain the spinal alignment
Anterior Cervical Discectomy
This operation is performed on the neck in order to relieve pressure on the spinal cord one or on one or more nerve roots. Through a small incision in the anterior (or front) of the neck, the surgeon reaches the cervical spine. This will typically be a small horizontal incision in the crease of the skin if only one disc is to be removed. In the case of a more extensive operation, a slanted or longer incision may be required. After the surgeon separates the soft tissues of the neck, the bone spurs and intervertebral disc are removed. In addition, the nerve roots and spinal cord are decompressed. A small piece of bone or another device through spinal fusion is used to fill the space left between the vertebrae. Eventually, the vertebrae will fuse, joining together across that level.
Anterior Cervical Corpectomy
When cervical stenosis with spinal cord compression is caused by bone spur formations, which cannot be removed with a discectomy alone, a corpectomy is performed. While performing a corpectomy, to relieve pressure from the spinal cord, the neurosurgeon removes a part or all of the vertebral body. One or more of these may be removed, including the adjoining discs for multilevel disease. The space between the vertebrae is filled using a small piece of bone or device through spinal fusion. Because more bone is removed this way, the recovery process for the fusion to heal and the neck to become stable generally lasts longer than the recovery process for anterior cervical discectomy. Depending on the amount of required spinal construction, the surgeon may also choose to support the anterior construct with posterior instrumentation and fusion.
Posterior Microdiscectomy
This procedure is executed through a small vertical incision in the posterior (back) of one’s neck, generally in the middle of it. For a large soft disc herniation located on the side of the spinal cord, this surgery may be considered. The surgeon uses a high speed burr to remove some of the facet joint, and the nerve root under the facet joint is identified. To free up and remove the disc herniation, the nerve root is gently moved aside.
Posterior Cervical Laminectomy and Fusion
A small incision in the middle of neck’s backside to remove the lamina in this procedure. To allow for removal of thickened ligament, bone spurs or disc material that may be pushing on the spinal cord, and/or nerve roots, the bone is removed. The foramen (the passageway in the vertebrae through which the spinal nerve roots travel) may also be enlarged in order to allow the nerves to pass through. Depending on the degeneration’s severity and amount of reconstruction needed, the surgeon may determine that a posterior spinal fusion is required. This would be an addition to the laminectomy, intended to maintain proper spinal stability and alignment. This may reduce the risk of requiring future interventions at those levels.
RISKS AND OUTCOME
As with any surgery, complications are fairly uncommon, but the following risks may be associated with cervical spine surgery:
- Infection
- Chronic arm or neck pain
- Inadequate symptom relief
- Damage to the nerves and the nerve roots
- Damage to the spinal cord (about 1 in 10,000 chance), resulting in paralysis
- Spinal instability
- Damage to the trachea, esophagus, or vocal cords from anterior approach
- Injury to the carotid or vertebral arteries, possibly resulting in stroke from anterior approach
- Fusion that does not occur (pseudarthrosis)
- Instrumentation breakage and/or failure
- Persistent swallowing or speech disturbance
- Leakage of cerebrospinal fluid
The benefits of every surgery should always be weighed carefully against the surgery’s risks. Although a large percentage of cervical spine patients report significant pain relief after surgery, no guarantee can be provided that surgery will help every individual.
FOLLOW-UP
The doctor will give you specific instructions post-surgery, typically prescribing pain medication. Depending on the type of surgery, the doctor will also help determine when the patient can resume everyday activities, such as driving, returning to work, and exercising. Certain patients may also benefit from physical therapy or supervised rehabilitation after their surgery. While the patient gradually returns to their normal activity, discomfort is expected. However, pain is a warning signal that a patient might need to slow down.
Postoperatively, the neurosurgeon may request x-rays of the spine to assess alignment, status of the instrumentation, and fusion. These will also help the doctor monitor levels of the spine adjacent to the surgery.
