You may be asked to take a variety of diagnostic tests. The tests are chosen based upon what your physician suspects is the cause of your pain. These are the most common diagnostic tests:
An X-ray is a painless process that uses radioactive materials to take pictures of bone. If your doctor suspects vertebral degeneration, X-rays can be used to verify a decrease in the height of space between discs, bone spurs, nerve bundle sclerosis (hardening), facet hypertrophy (enlargement), and instability during flexion or extension of limbs. X-rays show bones, but not much soft tissue, so they will definitely be used if fractures, infections, or tumors are suspected.
MRI Scan (Magnetic Resonance Imaging)
By using magnetic and radio waves, the MRI creates computer-generated images. The MRI is able to cut through multiple layers of the spine and show any abnormality of soft tissues, such as nerves and ligaments. The test also can be used to verify loss of water in a disc, facet joint hypertrophy (enlargement), stenosis (narrowing of spinal canal), or a herniated disc (protrusion or rupture of the intervertebral disc).
Bone Density Test
The Bone Density test can assess an individual’s risk for developing fractures. The risk of fracture is affected by age, body weight, history of prior fracture, family history of osteoporotic fractures and life style issues such as cigarette smoking and excessive alcohol consumption. These factors are taken into consideration when deciding if a patient needs therapy.
EMG/SSP (Electrodiagnostic Study)
An electromyogram (EMG) is a test that looks at the function of the nerve roots leaving the spine. The test is done by inserting tiny electrodes into the muscles of the lower extremity. By looking for abnormal electrical signals in the muscles, the EMG can show if a nerve is being irritated, or pinched as it leaves the spine. Think of how you test the wiring on a lamp. If you place a working bulb into the lamp, and the bulb lights up, you assume that the wiring is okay. However, what if the bulb does not light up? You can safely assume that something is probably wrong with the wiring, like the lamp is unplugged, or a short circuit has occurred. By using the muscles like the light bulb in the lamp, the EMG is able to determine the condition of the nerves that supply those muscles, like the wiring on the lamp. If the EMG machine finds that the muscles (the light bulb) are not working properly, the doctor can assume that the nerves (the wiring) must be getting pinched somewhere.
Facet Joint Block
Like any joint in the body, facet joints can cause pain if they are irritated or inflamed. The facet joint block is a procedure where a local anesthetic medication (such as lidocaine or Novocain) is injected into the facet joint. This same type of medication is used by a dentist to numb your jaw, or a doctor to sew up a laceration. The lidocaine actually numbs the area around the facet joint. If all your pain goes away, the doctor can assume that the facet joint is a problem.
Further lab tests may be done to check for problems that are not related to deterioration of the spine. Other testing can help determine the presence of serious problems such as: an infection, arthritis, cancer, or an aortic aneurysm. The most frequent lab test is blood sampling.