Various techniques are available to determine the cause of pain, including pain measurement tools and imaging tests. Your doctor will talk to you about your symptoms and ask about your history of illness, injury or surgery. You may be asked to fill out a questionnaire to assess the intensity and location of your pain.
Your doctor will also perform a physical examination, and may order blood tests or X-rays. Tests used to diagnose the cause of pain may include:
An FDA advisory committee recently recommended that the FDA set certain limits on acetaminophen, a drug that is used in many prescription and nonprescription medicines to relieve pain and reduce fever.
Those limits could include taking off the market some prescription drugs, such as the painkillers Percocet and Vicodin, which combine acetaminophen with other active ingredients.
The reason for the proposed limits is the risk of liver damage from taking too much acetaminophen.
CT or CAT scan: Computed tomography (CT) or computed axial tomography (CAT) scans use X-rays and computers to produce an image of a cross-section of the body. During the test, you will be asked to lie as still as possible on a table. The table will move through a large, donut-shaped scanning device. Sometimes, an intravenous (injected into a vein) contrast material is required for a CAT scan. In such cases, you may have a blood test before the CAT scan appointment. Most CAT scan procedures take 15-60 minutes.
MRI:Magnetic resonance imaging produces very clear pictures of the body without the use of X-rays. This test uses a large magnet, radio waves and a computer to produce images. In most cases, an MRI takes 40 to 80 minutes, during which time several dozen images may be obtained. Certain MRI exams require an injection of a contrast material called gadolinium, which helps identify certain anatomic structures on the scan images. Due to the magnets used in the study, some people (like those who have pacemakers) should not have an MRI.
Discography: During discography a contrast dye is injected into the spinal disc that is thought to be causing back pain. The dye outlines the damaged areas on X-rays taken following injection. This procedure may be suggested for people who are considering surgery or IDET (intradiscal electrothermal treatment).
Myelograms: As in discography, during the myelogram procedure, a contrast dye will be injected into the spinal canal to enhance the diagnostic ability of X-ray. Doctors are able to see on X-ray the image of the spinal cord and can identify nerve compression caused by herniated discs or fractures.
EMG: This procedure allows doctors to evaluate the activity of the muscles. During the procedure, very fine needles are inserted in muscles to measure the muscles response to signals from the brain or spinal cord.
Bone scans: Bone scans are used to diagnose and monitor infection, fracture, or other disorders in the bone. During a bone scan, a small amount of radioactive material is injected into the bloodstream. The material will collect in the bones, particularly in areas with any abnormality. Scanner-generated images are sent to a computer to identify specific areas of irregular bone metabolism or abnormal blood flow.
Ultrasound imaging: Also called ultrasound scanning or sonography, this test uses high-frequency sound waves to obtain images inside the body. The sound wave echoes are recorded and displayed as a real-time visual image.