A lumbar spine X-ray is an imaging test that helps doctors view the anatomy of your lower back.
The lumbar spine is made up of five vertebral bones, the sacrum (the bony “shield” at the back of your pelvis), and the coccyx (tailbone). Large blood vessels, nerves, tendons, ligaments, and cartilage also comprise the lumbar spine.
An X-ray uses small amounts of radiation to view the bones of the body. When it is focused on the lower spine, an X-ray can help detect abnormalities, injuries, or diseases of the bones in that area. According to the Mayo Clinic, a lumbar spine X-ray can show whether you have arthritis or broken bones in your back, but it cannot show other problems with the muscles, nerves, or discs. (Mayo)
Your doctor could order a lumbar spine X-ray for a variety of reasons: to view an injury from a traumatic fall or accident, to monitor the progression of a disease like osteoporosis, or to determine the effectiveness of a treatment.
An X-ray is a useful test for many conditions. It can help your doctor understand the cause of chronic back pain or view the effects of injuries, disease, or infection. Your doctor may order a lumbar spine X-ray to diagnose:
- birth defects that affect the spine
- injury or fractures to the lower spine
- low back pain that is severe or lasts for more than four to eight weeks
- osteoarthritis (arthritis affecting the joints)
- osteoporosis (a condition that causes your bones to thin)
abnormal curvature or degenerative changes in your lumbar spine (such as bone spurs)
Your doctor might also use other imaging tests along with an X-ray to determine the cause of your back pain. These include a magnetic resonance imaging (MRI) scan, ultrasound, or computed tomography (CT) scan. Each of these scans results in a different type of image.
All X-rays involve exposure to a small amount of radiation. This is typically harmless, but it is an important issue if you are pregnant or could be pregnant. The amount of radiation used is considered safe for adults, but not for a developing fetus. Be sure to tell your doctor if you are pregnant or believe you may be pregnant.
According to the Radiological Society of North America, X-rays are routine procedures and involve almost no preparation on the part of the patient. (RNSA)
You will be instructed to remove any jewelry and other metallic items from your body before the X-ray is taken. Tell your doctor if you have any metal implants from prior surgeries. Most likely, you will change into a hospital gown for the test in order to prevent any buttons or zippers on your clothing from affecting the quality the X-ray images.
X-rays are performed in a hospital’s radiology department or at a clinic that specializes in diagnostic procedures.
After you lie down on a table, a technician will move a large camera connected to a steel arm over your lower back. A film inside the table below you will capture the X-ray images of your spine as the camera moves overhead.
The technician will ask you to lie in several positions during the test, including on your back, side, and stomach. Some images may be taken while you are standing.
While the images are being recorded, you will have to hold your breath and remain still. This ensures that the images are as clear as possible.
After the test, you can change back into your regular clothes and go about your day right away.
Your radiologist and doctor will review the X-rays and discuss their findings. Results from your X-ray may be available the same day.
Your doctor will determine how to proceed depending on what the X-rays show. He or she may order additional imaging scans, blood tests, or other tests to help make an accurate diagnosis.