In an era of tremendous technological advances in medicine, it is very tempting to “jump” to quick conclusions, diagnosis or recommendations solely based on high end technology like MRI. Many conservative and even surgical recommendations in patients with low back pain are based almost exclusively on abnormal MRI findings. However; some lumbar MRI findings do not correlate very accurately with the presence or not of low back pain.
In a study published by Jarvik in Spine in 2001 he reported MRI findings on 148 asymptomatic subjects. The results showed:
- 83% with moderate to severe desiccation of one or more discs
- 64% with one or more bulging discs.
- 56% with loss of disc height.
- 32% had at least one disc protrusion
- 6% had one or more disc extrusions
Clearly, many abnormal MRI findings were fairly common in patients without low back pain and were therefore of limited diagnostic value. However; findings of spinal stenosis, root compression and disc extrusions were diagnostically and clinically relevant despite being less common.
Nothing can replace the value of a thorough history and physical performed by an experienced specialist. The MRI evaluation coupled with the physical findings increases substantially the specificity and sensitivity of the MRI as a screening tool. In cases where the diagnosis is still in doubt, other studies such as discograms could be recommended to help shed light into the diagnostic dilemma.