A recent study published in SPINE investigated whether multiple MRIs are more strongly associated with lower back pain as opposed to single MRI findings.
Previous studies have indicated there is a small to moderate association between magnetic resonance (MRI) findings and lower back pain. However, these findings are potentially limited due to the approaches used to interpret the MRI results and hence may be the reason why a weak association is observed. Also, the majority of previous research has only included single MRI findings, such as disc degeneration or endplate signal changes, to investigate the association between current or future back pain outcomes and MRI findings and may be one of the reasons why only small to moderate associations are identified.
As some patients may have different sources contributing to their pain, the use of multiple MRI findings as opposed to a single MRI finding to assess the individual may potentially be a better diagnostic approach. However, there is limited research into whether a combination of multiple different MRIs findings has a stronger association with lower back pain. Some studies have shown that a combination of disc degeneration and endplate signal changes, whether anatomical or body structure changes to the cartilage or vertebrae, are more strongly associated with more severe lower back pain than each one in isolation.
Given that the preliminary evidence suggests that a combination of multiple MRI findings may be more strongly related to lower back pain, lumbar (lower back) pathology plays a potentially significant role in lower back pain. Therefore, researchers in Australia and Denmark recently conducted an exploratory study to investigate whether the number of different MRI findings has a stronger association with lower back pain compared to a single MRI finding. They assessed data collected from two different studies to compare previous and future lower back pain and their results were published in the journal SPINE.
The researchers first assessed a cross-sectional study from Denmark that included 412 individuals aged 40 years old who underwent an MRI examination to assess their current and past lower back pain. The primary outcome of this study was the presence of lower back pain in the previous year. The second study they assessed was a longitudinal study conducted in Australia which included 76 individuals who were recovering from a recent episode of acute lower back pain who had had an MRI within three months of recovery. The researchers followed the participants for 12 months to assess whether they suffered from lower back pain recurrence. Neither study reported on inflammatory spinal diseases or specific pathologies such as fractures, infection, or malignancy but rather focused on degenerative MRI findings. The MRI findings were reported by a single radiologist blinded to patient outcomes in both studies.
Assessing the relationship between the number of different MRI findings in each individual in both studies and the association with lower back pain, the researchers found the risk of a lower back pain outcome increased as the number of MRI findings increased. Individuals who underwent three MRIs compared to those who underwent none in the cross-sectional study had a substantially greater risk of lower back pain in the previous year, with 69% of participants reporting lower back pain in the last year. In the longitudinal study, after 12 months of follow-up, 39% of participants reported recurrence of lower back pain which limited their activity, providing evidence supporting the association between multiple MRI findings and an increased risk of future lower back pain recurrence.
Hence the data from both studies indicate on average a higher number of different MRI findings are associated more closely with lower back pain outcomes than single MRI findings. Further research is necessary to investigate which MRI findings are independently associated with lower back pain outcomes and to gain a greater understanding of the role in which pathology visible on MRI findings plays in lower back pain.
Written by Lacey Hizartzidis, PhD
Reference: Hancock MJ, Kjaer P, Kent P, Jensen RK, Jensen TS. Is the Number of Different MRI Findings More Strongly Associated With Low Back Pain Than Single MRI Findings? Spine (Phila Pa 1976). 2017 Sep 1;42(17):1283-1288. doi: 10.1097/BRS.0000000000002102.
