Abstract
Background
Criticisms about overuse of MRI in low back pain are well documented. Yet, with the exception of suspicion of serious pathology, little is known about factors that influence clinicians' preference for MRI. We investigated the factors associated with physiotherapists' preference for MRI for patients consulting with benign low back and leg pain (LBLP) including sciatica.
Methods
Data were collected from 607 primary care patients consulting with LBLP and assessed by 7 physiotherapists, in the ATLAS cohort study. Following clinical assessment, physiotherapists documented whether he/she wanted the patient to have an MRI. Factors potentially associated with clinicians' preference for imaging were selected a priori, from patient characteristics and clinical assessment findings. A mixed-effect logistic regression model examined the associations between these factors and physiotherapists' preference for MRI.
Results
Physiotherapists expressed a preference for MRI in 32% (196/607) of patients, of whom 22 did not have a clinical diagnosis of sciatica (radiculopathy). Factors associated with preference for MRI included; clinical diagnosis of sciatica (OR 4.23: 95% CI 2.29,7.81), greater than 3 months pain duration (OR 2.61: 95% CI 1.58,4.30), high pain intensity (OR 1.24: 95%CI 1.11,1.37), patient's low expectation of improvement (OR 2.40: 95% 1.50,3.83), physiotherapist's confidence in the diagnosis (OR 1.19: 95% CI 1.07,1.33) with greater confidence associated with higher probability of preference for MRI.
Conclusion
A clinical diagnosis of sciatica and longer symptom duration were most strongly associated with physiotherapists' preference for MRI. Given current best practice guidelines, these appear to be justifiable reasons for wanting patients to have an MRI.
Conflicts of interest: None
Funding
SE was supported through an NIHR internship linked to an NIHR Research Professorship awarded to NEF (RP-01-015). NEF is an NIHR Senior Investigator. KK is supported through a HEFCE Senior Clinical Lecturer award. The views and opinions expressed therein are those of the authors and do not necessarily reflect those of the NIHR, NHS or the Department of Health
