The Facts about MRI’s

We have noticed an aggressive trend of increase MRI studies on low back patients over the past year. It is important to note that the false positive rates for lumbar MRI’s are quite high. Several studies or investigations have been conducted looking at groups of people who have never experienced back pain and had MRI’s taken. These asymptomatic individuals presented with disk bulges, protrusions, and extrusions. We see this often in the clinic as many patients come in with MRIs that show pathology on the opposite of involvement and we are quick to point out the importance of these false positive rates.



The McKenzie method or mechanical diagnosis and therapy (MDT) utilizes a phenomenon known as “centralization” which has been shown to be a more accurate indicator as to successful outcome for discogenic problems. Studies by Donelson have reported that referred symptoms to the buttock, thigh or leg in 89% of patients with acute pain, centralized during mechanical assessment. Of this centralization group, 91% have excellent outcomes resulting in complete relief of pain and restoration to function.



Some insurance plans are now requiring an MDT assessment be done prior to MRI studies to avoid the problematic issue of false positives and excessive cost. Of those patients that do centralize, we not only reduce their pain and restore function, but they also learn a valuable tool on how to prevent recurrent episodes.

Back to the basics

This past month, we have seen an increase in the number of patients with pain or parathesia that travels into the lower extremity. Back in 1990, a study was published “The centralization phenomenon: It’s usefulness in evaluating and treating referred pain”. In this study of 87 patients, 87% of all acute, sub- acute and chronic patients exhibited centralization. 81% of the centralizers and even 33% of the non-centralizers had good or excellent outcomes. Of this group, only 4 were surgical patients and were also non-centralizers and did quite well with surgery as well. The conclusion is that centralization is that it occurred commonly and its present or absence was a strong predictor of treatment outcome and present or absence of surgical disk pathology.


Very often our patients in these times are very eager to obtain an MRI study of their spine which will indicate a history of what condition their spine has been in and is not always conclusive to the source of pain. Centralization has proven to be a very valid predictor of treatment and outcomes and should still be considered the gold standard before more invasive procedures are tried. We will be compiling studies which have supported the importance of mechanical diagnosis and therapy and the issue of centralization in hope educational white paper or pamphlet which will help guide decision making for diagnostic decision making among our patients.