Radiological Imaging & Other Tests
These radiological imaging tests help your doctor see the anatomy of your spine. There are several other kinds of diagnostic imaging tests that are available that can be ordered if indicated. Below is some basic information on these various tests.
X-rays show problems with bones, such as infection, bone tumors, or fractures. X-rays of the spine also can give your doctor information about how much degeneration has occurred in the spine, by showing the amount of space in the neural foramina and between the discs. X-rays are usually the first test ordered before any of the more specialized tests. Special X-rays called flexion and extension X-rays may help to determine if there is instability between vertebrae. These X-rays are taken from the side as you lean as far forward and then as far backward as you can. Comparing the two X-rays allows the doctor to see how much motion occurs between each spinal segment.
The magnetic resonance imaging (MRI) scan uses magnetic waves to create pictures of the spine in slices. The MRI scan shows the spine bones, as well as the soft tissue structures such as the discs, joints, and nerves.
MRI scans are painless and don't require needles or dye. The MRI scan has become the most common test to look at the spine after X-rays have been taken. MRI scans are very good tests for assessing the discs and nerve roots in the case of suspected disc herniations. Unfortunately,, MRI tests are expensive and not always covered by insurance.
The computed tomography (CT) scan is a special type of X-ray that lets doctors see slices of bone tissue. The machine uses a computer and X-rays to create these slices. It is used primarily when problems are suspected in the bones. To the untrained eye the appearance of a CT is similar to an MRI,
The myelogram is a special kind of X-ray test where a special dye is injected into the spinal sac. The dye shows up on an X-ray. It helps a doctor see if there is a herniated disc, pressure on the spinal cord or spinal nerves, or a spinal tumor. Before the CT scan and the MRI scan were developed, the myelogram was the only test that doctors had to look for a herniated disc. The myelogram is still used today but not nearly as often. The myelogram is usually combined with CT scan to give more detail.
A bone scan is a special test where radioactive tracers are injected into your blood stream. The tracers then show up on special X-rays of your neck. The tracers build up in areas where bone is undergoing a rapid repair process, such as a healing fracture or the area surrounding an infection or tumor. Usually the bone scan is used to locate the problem, and other tests such as the CT scan or MRI scan are then used to look at the area in detail.
Other Non-Imaging Tests
Your doctor may also ask you to have other tests done.
An electromyogram (EMG) is a special test used to determine if there are problems with any of the nerves going to the upper limbs. EMGs are usually done to determine whether the nerve roots have been pinched by a herniated disc. During the test, small needles are placed into certain muscles that are supplied by each nerve root. If there has been a change in the function of the nerve, the muscle will send off different types of electrical signals. The EMG test reads these signals and can help determine which nerve root is involved.
Not all causes of neck pain are from degenerative conditions. Doctors use blood tests to identify other conditions, such as arthritis or infection. Other tests may be needed to rule out problems that do not involve the spine.