Lumbosacral spine x-ray

Answer 1

Definition

A lumbosacral spine x-ray is a picture of the small bones (vertebrae) in the lower part of the spine (the lumbar region) and the sacrum, the area that connects the spine to the pelvis.

Alternative Names

X-ray - lumbosacral spine; X-ray - lower spine

How the test is performed

The test is done in a hospital radiology department or your health care provider's office by an x-ray technician. You will be asked to lie on the x-ray table in different positions. If the x-ray is being done to diagnose an injury, care will be taken to prevent further injury.

The x-ray machine will be placed over the lower part of your spine. You will be asked to hold your breath as the picture is taken so that the image will not be blurry. Usually three to five pictures are taken.

How to prepare for the test

Inform the health care provider if you are pregnant. Remove all jewelry.

How the test will feel

There is generally no discomfort associated with an x-ray, although the table may be cold.

Why the test is performed

Lumbosacral spine x-ray helps evaluate back injuries and persistent numbness, low Back pain, or weakness.

What abnormal results mean

• Bone spurs
• Deformities in the curvature of the spine
• Degeneration of the vertebrae
• Disk problems such as herniated disk
• Dislocations
• Fractures
• Osteoporosis

What the risks are

There is low radiation exposure. X-rays are monitored and regulated to provide the minimum amount of radiation exposure needed to produce the image. Most experts feel that the risk is low compared with the benefits.

Pregnant women and children are more sensitive to the risks of x-rays.

Special considerations

There are a number of back problems that an x-ray will not detect because they involve the muscles, nerves, and other soft tissues. A lumbosacral spine CT or lumbosacral spine MRI are better options for soft tissue disorders.

ReferencesMettler FA. Skeletal system. In: Mettler FA, ed.Essentials of Radiology. 2nd ed. Philadelphia, Pa: Saunders Elsevier;2005:chap 8.

Answer 2

Definition

A lumbosacral spine x-ray is a picture of the small bones (vertebrae) in the lower part of the spine, which includes the lumbar region and the sacrum, the area that connects the spine to the pelvis.

Alternative Names

X-ray - lumbosacral spine; X-ray - lower spine

How the test is performed

The test is done in a hospital x-ray department or your health care provider's office by an x-ray technician. You will be asked to lie on the x-ray table in different positions. If the x-ray is being done to diagnose an injury, care will be taken to prevent further injury.

The x-ray machine will be placed over the lower part of your spine. You will be asked to hold your breath as the picture is taken so that the image will not be blurry. Usually three to five pictures are taken.

How to prepare for the test

Inform the health care provider if you are pregnant. Remove all jewelry.

How the test will feel

There is rarely any discomfort when having an x-ray, although the table may be cold.

Why the test is performed

Often, a health care provider will treat a person with low back pain for 4 to 8 weeks before ordering an x-ray.

The most common reason for lumbosacral spine x-ray is to look for the cause of low back pain that:

• Occurs after injury
• Is severe
• Does not go away after 4 to 8 weeks
• Is present in an older person

What abnormal results mean

Lumbosacral spine x-rays may show:

• Abnormal curves of the spine
• Abnormal wear on the cartilage and bones of the lower spine, such as bone spurs and narrowing of the joints between the vertebrae
• Cancer (although cancer often cannot be seen on this type of x-ray)
• Fractures
• Signs of thinning bones (osteoporosis)
• Spondylolisthesis, in which a bone (vertebra) in the lower part of the spine slips out of the proper position onto the bone below it

Though some of these findings may be seen on an x-ray, they are not always caused by a person's back.

Many problems in the spine cannot be diagnosed using a lumbosacral x-ray, including:

• Sciatica
• Slipped or herniated disc
• Spinal stenosis- narrowing of the spinal column

What the risks are

There is low radiation exposure. X-ray machines are checked on a regular basis to make sure they are as safe as possible. Most experts feel that the risk is low compared with the benefits.

Pregnant women should not be exposed to radiation, if at all possible. Care should be taken before children receive x-rays.

Special considerations

There are a number of back problems that an x-ray will not detect because they involve the muscles, nerves, and other soft tissues. A lumbosacral spine CT or lumbosacral spine MRI are better options for soft tissue disorders.

References

Stevens JM, Rich PM, Dixon AK. The spine. In: Adam A, Dixon AK, eds. Grainger & Allison's Diagnostic Radiology: A Textbook of Medical Imaging. 5th ed. New York, NY: Churchill Livingstone; 2008:chap 60.

Chou R, Qaseem A, Owens DK, Shekelle P; for the Clinical Guidelines Committee of the Amercian College of Physicians. Diagnostic imaging for low back pain: advice for high-value health care from the American College of Physicians. Ann Intern Med. 2011;154(3):181-189.

Reviewed By

Review Date: 02/07/2011

Linda Vorvick, MD, Family Physician, Medical Director, MEDEX Northwest Division of Physician Assistant Studies, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.