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Introduction
Consider the following when making your decision about having
magnetic
resonance imaging (MRI):
- There is a good chance that your new (acute)
low
back pain will improve within 6 weeks-most cases do.
- Avoid requesting costly imaging tests for acute low back pain. They
usually provide no helpful early information. If you don't have signs of a
serious medical condition (such as spinal infection or bone cancer), don't
ask for or agree to imaging tests unless you have low back pain that has
persisted through at least 4 weeks of nonsurgical treatment.
- MRI is the best test for showing a
herniated
disc, soft-tissue damage, tumor, or infection. 1
MRI also has the advantage of not using the ionizing radiation that the CT
scan does.
- Your doctor will probably wait to order an MRI for nerve-related symptoms
that don't go away within at least 4 weeks, because these symptoms often go
away on their own.
- A technique called rapid MRI is probably no better than a standard
X-ray
for diagnosing the cause of back pain or deciding what treatment to use.
Medical
Information
What is low back pain, and what causes it?
Strained muscles and ligaments are the most common cause of low back pain and
stiffness. This type of low back trouble generally goes away after 4 to 6 weeks
of nonsurgical treatment.
Pressure on a spinal nerve can cause
sciatica symptoms, including back pain and/or leg numbness, pain, tingling, weakness,
or loss of reflexes. Causes of sciatica include:
- Herniated disc, which usually gets better within a month or two.
- Arthritis.
- Spinal
stenosis.
Other serious causes of back pain, such as infection, a tumor, or cancer, are
rare. Only about 5% of low back pain cases are caused by serious disease or
cause nerve-related problems that could be corrected with surgery. Imaging is
helpful for diagnosing and planning treatment for these types of conditions.
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What are the risks of not treating low back pain?
We very often don't know what causes low back pain and, fortunately, it
usually goes away on its own. But sometimes back pain is a sign of tight or weak
muscles, poor posture, stress, or being overweight. It can also be a symptom of
another condition, such as infection, a tumor, or a problem such as a herniated
disc or spinal stenosis. If your back pain is caused by one or more of these
problems and you don't take care of it, you could be in for more low back pain,
decreased function, or other health problems in the future.
If your pain hasn't begun to subside after a couple of days of home
treatment, see your doctor. After doing a health
history and physical exam for low back pain, your doctor can recommend
treatment, possibly including some physical therapy. You probably won't have any
imaging tests unless your doctor sees signs of a serious condition or nerve
problems.
What types of problems can magnetic resonance imaging (MRI) find?
An MRI is not a standard test for finding the cause of low back pain. As we
age, we all develop changes in our spines that appear "abnormal" on an
MRI , but in most people these changes don't cause symptoms.
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A complete medical history and physical exam are enough to diagnose and treat
most low back pain.
Generally, an MRI is best used when your doctor suspects a specific problem
after completing your medical history and physical exam. An MRI can:
- Detect problems of the spinal discs, such as a ruptured disc. The test
will also help determine whether a disc is pressing on a nerve.
- Detect areas of the spinal canal that are abnormally narrowed (spinal
stenosis).
- Detect tumors of the spinal cord. The tumors that most commonly spread to
the spine include those from prostate, breast, or lung cancer.
- Further evaluate areas of joint inflammation (arthritis) or abnormal bone
loss discovered during an X-ray test or a bone scan.
- Locate areas of the spinal cord that are not receiving an adequate blood
supply.
- Detect areas of infection within the outermost layer of the spine and the
spinal cord.
- Detect areas of nerve damage in the spinal cord caused by trauma or
disease, such as multiple
sclerosis.
- Evaluate spinal problems that have been present since birth (congenital).
For an idea of one type of problem an MRI can help identify, see MRI images
of the lumbar spine:
MRI alone may not accurately show the source of your pain. Over time, we all
develop changes in our spines that appear "abnormal" on an MRI, though
these changes don't necessarily cause symptoms. 4
Before you make a decision to have a surgery, it is important that your
symptoms, physical examination, and imaging studies all point to the same source
of back or leg pain.
If you need more information, see the topic
Low
Back Pain.
Your Information
Your choices are:
- Have magnetic resonance imaging (MRI).
- Don't have magnetic resonance imaging (MRI).
The decision about whether to have an MRI takes into account your personal
feelings and the medical facts.
Deciding about having an MRI
| Reasons to have an MRI |
Reasons not to have an MRI |
- You are looking for the cause of severe, persistent
sciatica
(causing severe pain, numbness, tingling, weakness, or loss of
reflexes in your leg).
- Your doctor suspects that you may have some other problem (such as
spinal infection or cancer) that is causing your symptoms.
- You have severe, persistent, and disabling back or leg symptoms,
so continued non-surgical treatment may not be a reasonable option.
- Your doctor is planning surgery for a
herniated
disc and needs to see the disc clearly. For more information,
see: Should
I have surgery for a herniated disc?
Are there other reasons you might want to have an MRI?
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- You have not tried at least 4 weeks of nonsurgical treatment
(including ice, exercises, and monitoring your body mechanics).
- Your health history and physical examination revealed no signs of
disease or nerve problems.
- You have pain but are not disabled by it, and are learning to
manage your back pain by strengthening your abdomen and back muscles
and using home treatment measures.
- Other imaging tests provide as accurate a screening for your
particular situation as MRI does and are less expensive.
- You are not willing to have a surgical procedure.
Are there other reasons you might not want to have an MRI?
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Wise Health Decision
Use this worksheet to help you make your decision. After completing it, you
should have a better idea of how you feel about whether you should have magnetic
resonance imaging (MRI). Discuss the worksheet with your health professional.
Circle the answer that best applies to you.
| I have already had a thorough physical exam. |
Yes |
No |
Unsure |
| I have tried ice, exercises, and healthy back practices
for at least 4 weeks. |
Yes |
No |
NA* |
| I have severe, disabling sciatica symptoms, and MRI
results would help me make treatment decisions. |
Yes |
No |
Unsure |
| My doctor wants to check me for infection or cancer. |
Yes |
No |
Unsure |
| I am planning on having disc surgery, and the MRI results
are needed for surgery planning. |
Yes |
No |
Unsure |
| Another imaging test can provide the information my
doctor needs at less cost. |
Yes |
No |
Unsure |
| I have the financial resources or health insurance
coverage to cover the cost of an MRI. |
Yes |
No |
Unsure |
*NA = Not applicable
Use the following space to list any other important concerns you have about
this decision.
What is your overall impression?
Your answers in the above worksheet are meant to give you a general idea of
where you stand on this decision. You may have one overriding reason to have or
not have an MRI to learn more about your low back pain.
Check the box below that represents your overall impression about your
decision.
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Leaning toward having an MRI
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Leaning toward NOT having an MRI
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References
Citations
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Carragee
EJ, Hannibal M (2004). Diagnostic evaluation of low back pain. Orthopedic
Clinics of North America, 35(2004): 7–16.
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Jarvik
JG, et al. (2003). Rapid magnetic resonance imaging vs. radiographs for
patients with low back pain: A randomized controlled trial. JAMA,
289(21): 2810–2818.
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Jarvik
JG, Deyo RA (2002). Diagnostic evaluation of low back pain with emphasis
on imaging. Annals of Internal Medicine, 137(7): 586–597.
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Borenstein
DG, et al. (2001). The value of magnetic resonance imaging of the lumbar
spine to predict low-back pain in asymptomatic subjects. Journal of
Bone and Joint Surgery, 83-A(9): 1306–1311.
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