Introduction
Neck pain has many causes. Mechanical neck pain comes from injury or
inflammation in the soft tissues of the neck. This is much different
and less concerning than symptoms that come from pressure on the nerve
roots as they exit the spinal column. People sometimes refer to this
problem as a pinched nerve. Health care providers call it cervical radiculopathy.
This guide will help you understand
- how the problem develops
- how doctors diagnose the condition
- what treatment options are available
Anatomy
What part of the neck is involved?
The spine is made of a column of bones. Each bone, or vertebra, is formed by a round block of bone, called a vertebral body.
A bony ring attaches to the back of the vertebral body. When the
vertebra bones are stacked on top of each other, the bony rings forms a
long bony tube that surrounds and protects the spinal cord as it passes through the spine.
Travelling from the brain down through the spinal column, the
spinal cord sends out nerve branches through openings on both sides of
each vertebra. These openings are called the neural foramina. (The term used to describe a single opening is foramen.)
The intervertebral disc sits directly in front of the opening. A bulged or herniated disc can narrow the opening and put pressure on the nerve. A facet joint
sits in back of the foramen. Bone spurs that form on the facet joint
can project into the tunnel, narrowing the hole and pinching the nerve.
An intervertebral disc fits between the vertebral bodies and
provides a space between the spine bones. The disc normally works like
a shock absorber. An intervertebral disc is made of two parts. The
center, called the nucleus, is spongy. It provides most of the shock absorption. The nucleus is held in place by the annulus, a series of strong ligament rings surrounding it. Ligaments are strong connective tissues that attach bones to other bones.
Related Document: A Patient's Guide to Cervical Spine Anatomy
Causes
Why do I have this problem?
Cervical radiculopathy is caused by any condition that puts pressure
on the nerves where they leave the spinal column. This is much
different than mechanical neck pain. Mechanical neck pain is caused by
injury or inflammation in the soft tissues of the neck, such as the
discs, facet joints, ligaments, or muscles.
The main causes of cervical radiculopathy include degeneration, disc herniation, and spinal instability.
Degeneration
As the spine ages, several changes occur
in the bones and soft tissues. The disc loses its water content and
begins to collapse, causing the space between the vertebrae to narrow.
The added pressure may irritate and inflame the facet joints, causing
them to become enlarged. When this happens, the enlarged joints can
press against the nerves going to the arm as they try to squeeze
through the neural foramina. Degeneration can also cause bone spurs to
develop. Bone spurs may put pressure on nerves and produce symptoms of
cervical radiculopathy.
Herniated Disc
Heavy, repetitive bending, twisting, and lifting can place extra
pressure on the shock-absorbing nucleus of the disc. A blow to the head
and neck can also cause extra pressure on the nucleus. If great enough,
this increased pressure can injure the annulus (the tough, outer ring
of the disc). If the annulus ruptures, or tears, the material in the
nucleus can squeeze out of the disc. This is called a herniation.
Although daily activities may cause the nucleus to press against the
annulus, the body is normally able to withstand these pressures.
However, as the annulus ages, it tends to crack and tear. It is
repaired with scar tissue. Over time, the annulus becomes weakened, and
the disc can more easily herniate through the damaged annulus. If the
herniated disc material presses against a nerve root it can cause pain,
numbness, and weakness in the area the nerve supplies.
Spinal Instability
Spinal instability means there is extra movement among the bones of the spine. Instability in the cervical spine
(the neck) can develop if the supporting ligaments have been stretched
or torn from a severe injury to the head or neck. People with diseases
that loosen their connective tissue may also have spinal instability.
Spinal instability also includes conditions in which a vertebral body
slips over the one just below it. When the vertebral body slips too far
forward, the condition is called spondylolisthesis. Whatever
the cause, extra movement in the bones of the spine can irritate or put
pressure on the nerves of the neck, causing symptoms of cervical
radiculopathy.
Symptoms
What does the condition feel like?
The symptoms from cervical radiculopathy are from pressure on an
irritated nerve. These symptoms are not the same as those that come
from mechanical neck pain. Mechanical neck pain usually starts in the
neck and may spread to include the upper back or shoulder. It rarely
extends below the shoulder. Headaches are also a common complaint of
both radiculopathy and mechanical neck pain.
The pain from cervical radiculopathy usually spreads further down
the arm than mechanical neck pain. And unlike mechanical pain,
radiculopathy also usually involves other changes in how the nerves
work such as numbness, tingling, and weakness in the muscles of the
shoulder, arm, or hand. With cervical radiculopathy, the reflexes in
the muscles of the upper arm are usually affected. This is why doctors
check reflexes when people have symptoms of cervical radiculopathy.
Diagnosis
How do doctors diagnose the problem?
Doctors gather the information about your symptoms as a way to
determine which nerve is having problems. Diagnosis begins with a
complete history of the problem. Your doctor will ask questions about
your symptoms and how your problem is affecting your daily activities.
Your answers can help your doctor determine which nerve is causing
problems.
Next, the doctor examines you to see which neck movements cause pain
or other symptoms. Your skin sensation, muscle strength, and reflexes
are tested in order to tell where the nerve problem is coming from.
X-rays of the cervical spine can show the cause of pressure on the
nerve. The images show whether degeneration has caused the space
between the vertebrae to collapse. They may also show if a bone spur is
pressing against a nerve.
If more information is needed, your doctor may order magnetic resonance imaging
(MRI). The MRI machine uses magnetic waves rather than X-rays to show
the soft tissues of the body. This test gives a clear picture of the
discs, nerves, and other soft tissues in the neck. The machine creates
pictures that look like slices of the area your doctor is interested
in. The test does not require any special dye or needles and is
painless.
Sometimes it isn't clear where the nerve pressure is coming from.
Symptoms of numbness or weakness can also happen when the nerve is
being pinched or injured at other points along its path. (An example of
this is pressure on the median nerve in the wrist, known as carpal tunnel syndrome.)
Electrical studies of the nerves going from the neck to the arm may be
requested by your doctor to see whether the nerve problem is in the
neck or further down the arm. However, most doctors take X-rays and try
other forms of treatment before ordering electrical tests. These tests
are usually only needed when the diagnosis is not clear.
If your doctor orders electrical studies, several tests are available to see how well the nerves are functioning, including the electromyography
(EMG) test. This test measures how long it takes a muscle to work once
a nerve signals it to move. The time it takes will be slower if nerve
pressure from radiculopathy has affected the strength of the muscle.
Another electrical test that may be used instead of EMG is cervical root stimulation
(CRS). This test involves putting a small needle through the back of
the neck into the nerve where it leaves the spinal column. Readings of
muscle action are then taken of the muscles on the front and back of
the upper arm and along the inside of the lower arm. Doctors use the
readings to determine which nerve is having problems.
Treatment
What treatment options are available?
Nonsurgical Treatment
Unless the nerve problem is getting worse rapidly, most doctors will begin with nonsurgical treatments.
At first, your doctor may prescribe immobilization of the neck.
Keeping the neck still for a short time can calm inflammation and pain.
This might include one to two days of bed rest and the use of a soft neck collar.
This collar is a padded ring that wraps around the neck and is held in
place by a Velcro strap. Normally, a patient need only wear a collar
for one to two weeks. Wearing it longer tends to weaken the neck
muscles.
Doctors prescribe certain types of medication for patients with
cervical radiculopathy. Severe symptoms may be treated with narcotic
drugs, such as codeine or morphine. But these drugs should only be used
for the first few days or weeks after problems with radiculopathy start
because they are addictive when used too much or improperly. Muscle
relaxants may be prescribed to calm neck muscles that are in spasm. You
may be prescribed anti-inflammatory medications such as aspirin or
ibuprofen.
Some doctors have their patients work with a physical therapist. At
first, treatments are used to ease pain and inflammation. Electrical
stimulation treatments can help calm muscle spasm and pain. Traction is
a way to gently stretch the joints and muscles of the neck. It can be
done using a machine with a special head halter, or the therapist can apply the traction pull by hand.
Some patients are given an epidural steroid injection (ESI). The spinal cord travels in a tube within the bones of the spinal canal. The cord is covered by a material called dura. The space between the dura and the spinal column is the epidural space.
It is thought that injecting steroid medication into this space fights
inflammation around the nerves, the discs, and the facet joints. In
some cases, the steroid injection is given around one specific nerve.
This is called a selective nerve block. The response to this treatment helps confirm which nerve root is causing the symptoms.
Doctors usually have their patients try nonoperative treatments for
at least three months before considering surgery. But when patients
simply aren't getting better, or if the problem is becoming more
severe, surgery may be suggested.
Surgery
Most people with cervical radiculopathy get better without surgery.
In rare cases, people don't get relief with nonsurgical treatments.
They may require surgery. There are several types of surgery for
cervical radiculopathy. These include
- foraminotomy
- discectomy
- fusion
Foraminotomy
A foraminotomy is done to open the neural foramen and relieve pressure on the spinal nerve root. A foraminotomy may be done because of bone spurs or inflammation.
Related Document: A Patient's Guide to Cervical Foraminotomy
Discectomy
In a discectomy, the surgeon removes the disc where it is pressing against a nerve. Surgeons usually perform this surgery from the front (anterior)of the neck. This procedure is called anterior cervical discectomy. In most patients, discectomy is done together with a procedure called cervical fusion, which is described next.
Related Document: A Patient's Guide to Cervical Discectomy
Fusion
A fusion surgery joins two or more bones into one solid bone. The
purpose for treating cervical radiculopathy with fusion is to increase
the space between the vertebrae, taking pressure off the nerve. The
surgery is most often done through the front of the neck. After taking
out the disc (discectomy), the disc space is filled in with a small
block of bone graft. The bone is allowed to heal, fusing the two
vertebrae into one solid bone. The space between the vertebrae is
propped and held open by the bone graft, which enlarges the neural
foramina, taking pressure off the nerve roots.
Related Document: A Patient's Guide to Anterior Cervical Discectomy and Fusion
Rehabilitation
Nonsurgical Rehabilitation
What should I expect from treatment?
Even if you don't need surgery, your doctor may recommend that
you work with a physical therapist. Patients are normally seen a few
times each week for one to two months. In severe cases, patients may
need a few additional weeks of care.
Your therapist creates a program to help you regain neck and arm
function. Treatments for cervical radiculopathy often include neck
traction, described earlier. Though neck traction is often done in the
clinic, your therapist may give you a traction device to use at home.
It is very important to improve the strength and coordination in the
neck and shoulder blade muscles. Your therapist can also evaluate your
workstation or the way you use your body when you do your activities
and suggest changes to avoid further problems.
After Surgery
Rehabilitation after surgery for cervical radiculopathy can be a
slow process. You will probably need to attend physical therapy
sessions for six to eight weeks, and you should expect full recovery to
take up to four months.
During physical therapy after surgery, your therapist may use
treatments such as heat or ice, electrical stimulation, massage, and
ultrasound to help calm pain and muscle spasm. Then you begin learning
how to move safely with the least strain on the healing neck.
As the rehabilitation program evolves, you will do more challenging
exercises. The goal is to safely advance your strength and function. As
your therapy sessions come to an end, your therapist will help you with
decisions about getting you back to work. Your therapist can do a work
assessment to make sure you'll be able to do your job safely. Your
therapist may suggest changes that could help you work safely, with
less chance of reinjuring your neck.
When your treatment is well under way, regular visits to the
therapist's office will end. The therapist will continue to be a
resource for you. But you will be in charge of doing your exercises as
part of an ongoing home program.
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