Often times when a patient presents to one of our clinics with a diagnosis of low back pain they have not had an MRI. The patient will ask the therapist if they should have had an MRI done to diagnosis the origin of their symptoms. As wonderful a technology as an MRI is it is not perfect. MRI's are medical imaging tools used to take pictures of what your spine looks like on the inside. Unfortunately it is a picture of a moment in time and may not give the whole story of what is happening to your low back.  

     Sometimes MRI's provide misleading information which is not good for the patient. Studies have shown that individuals (ages 20-80) who do not have low back pain (LBP) have positive MRI findings including bulging discs (52%), Herniated discs (28%), Degenerative discs in people over 60 (90%), joint findings (38%). Again these are people without LBP ! Also the likelihood of finding something goes up with  age. It is similar to how a photo of you now versus a photo from your youth shows how you have aged on the outside. An MRI shows signs of aging on the inside which does not necessarily mean anything is wrong. So the fact that so many asymptomatic individuals have positive findings on MRI makes it difficult to know what is relevant in individuals that do have LBP. In some individuals that have positive findings and are having LBP, surgeries or other invasive procedures such as injections are often recommended. These procedures are costly, potentially dangerous, and may not be necessary or beneficial.   

     Physical therapists are in a unique position to be an effective treatment option for low back pain. We do not rely on a picture to help us with our assessment. We also do not use expensive testing procedures. Physical therapists use their evaluation skills to assess an individual's strength, range of motion, postural habits, and flexibility. We also assess how your low back pain responds to certain types of loading stress and movement strategies. This helps us to determine the best type of treatment to help you abolish your low back pain and prevent future episodes.  

Sources:

Boden et al. Abnormal magnetic resonance scans of the lumbar spine in asymptomatic subjects. J Bone Joint Surg Am. 1990

Deyo et al. Magnetic resonance imaging of the lumbar spine. Terrific test or tar baby? N Engl J Med. 1994  

Flynn et al. Diagnostic imaging in LBP: a reminder that unnecessary imaging may do as much harm as good. JOSPT 2011

Although MRI's do have a high incidence of findings in asymptomatic individuals they are still a very helpful and important diagnostic tool. So, who should get an MRI then. Anyone with LBP and the following symptoms:

- Anyone 50 yrs. or older with a history of cancer

- Loss of bowel or bladder control  

- Urinary retention

- Numbness/loss of sensation in the saddle region    

  (groin and buttock)

- Progressive neurologic deficits (strength and    

   sensation)

- No improvement in pain after 4 weeks of  

  conservative care including physical therapy

If an individual has any of these symptoms with their LBP they should consult their physician as soon as possible. Further testing which could include an MRI, may be warranted.

If your only complaint is pain in the

low back and/or legs don't worry. What you are experiencing is normal and you will most likely get better. Also an MRI won't make you feel any better. Try to keep moving and stay as active as possible without aggravating your symptoms. Consult with a physical therapist as soon as possible so they can help you to reduce your pain and improve your function.