- Significant pain that lasts more than 1 - 2 months
- Symptoms such as pain, numbness, or tingling extending from the buttocks down the leg that are very severe or get worse
- Muscle weakness that is significant, persistent, or getting worse
- A previous accident or injury that might have affected the disks or vertebra
- A history of cancer
- Indications of an underlying disease such as fever or unexplained weight loss
- New pain that occurs in patients over 65 years of age
- Other red flag symptoms noted above
Magnetic Resonance Imaging (MRI). Magnetic resonance imaging (MRI) can provide very well-defined images of soft tissue and bone. The test is not painful or dangerous, but some people may feel claustrophobic in scanners where they are fully enclosed. MRIs can detect tears in the disks, disk herniation, or disk fragments. It can also detect spinal stenosis. and non-spinal causes of back pain, including infection and cancer.
MRI scans often detect spine abnormalities that are not causing symptoms in the patient. At least 40% of all adults have bulging or protruding vertebral disks, and most have no back pain. Also, the degree of disk abnormalities revealed by MRIs often has very little to do with the severity of the pain or the need for surgery. Disk abnormalities in people who have back pain may simply be a coincidence rather than an indication for treatment.
Patients are also more likely to think of themselves as having a serious back problem if abnormalities are identified on MRI scans, even if the scans do not result in treatment changes. This perception may sometimes slow down their recovery.
|Click the icon to see an image of a MRI machine.|
Bone Scintigraphy and SPECT Imaging. In rare cases, doctors may use bone scintigraphy (bone scanning) to determine abnormalities in the bones. The technique may be useful for early detection of spinal fractures, cancer that has spread to the bone, or certain inflammatory arthritic conditions. During this exam, a small amount of radioactive material is injected into a vein. It circulates through the body, and is absorbed by the bones. The bones can then be seen using x-rays or single photon emission computed tomography (SPECT).
An x-ray myelogram is an x-ray of the spine that requires a spinal injection of a special dye and the need to lie still for several hours to avoid a very painful headache. It has value only for select patients with pain on moving and standing. It has largely been replaced by CT and MRI scans.
Review Date: 04/07/2010
Reviewed By: Harvey Simon, MD, Editor-in-Chief, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.