Mark Hancock
The clinical importance of imaging findings in people with low back pain remains unclear and controversial. This is, in part, due to most of the existing research being cross-sectional. The few longitudinal studies that have been conducted typically only perform imaging once at baseline, then follow up with patients for clinical outcomes, such as pain and disability. Repeated imaging on different occasions has the potential to provide better insight into the importance of imaging findings.
The current study was not designed to directly change practice. The ultimate goal of this line of research is to identify which changes seen on MRI are the causes of an individual’s low back pain, leading to individualized and targeted treatment. Currently, most patients are considered to have nonspecific low back pain and treatments typically target the symptoms, not the causes.
The study has received substantial interest, especially when presented at international conferences. Many are surprised that research into changes in MRI findings over time has not been done and can see that this is an important gap in current knowledge. There is a degree of caution from some in the low back pain field who are aware of the problem of overuse of imaging in current practice. The distinction between imaging in clinical practice based on our current knowledge and imaging research to potentially drive better care in the future is critical.
Given the surprising finding that we, over time, identified changes in the controls without pain, we realized that we need to go back one step and investigate the reliability of reporting changes with repeated imaging of the lumbar spine. The changes we identified in people without pain may be true subclinical changes occurring over time, or artifacts of the repeat imaging sectioning, being at slightly different points on follow-up scans.
Currently, we are nearly finished conducting a follow-up study to explore these options. We have performed repeated MRI scans on 40 participants. All participants were imaged, then removed from the scanner, where they rested in a lying position for 15 minutes before being reimaged using an identical protocol.