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
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.
Traveling 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. Cervical Radiculopathy usually affects nerve roots C6 and C7, and can vary from slight pain to severe pain that will likely continue to increase if left untreated.
Related Document: A Patient's Guide to Cervical Spine Anatomy
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.
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.
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 aherniation.
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 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.
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 is likely to spread far enough to cause upper back or shoulder pain. Less frequently, radiculopathy extends below the shoulder, and can sometimes radiate through to the elbow or hand. 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.
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 theelectromyography (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.
Patients have many options regarding treatment, that vary widely between physical therapy all the way to slightly more invasive surgical procedures. Kansas City is lucky to have wonderful, top-notch orthopedic and neurological surgeons all throughout the metro. Talk to your doctor about what options would be best for you, and should physical therapy not help as much as you'd hope, surgery can be an option.