Effect of increased MRI and CT scan utilization on clinical decision-making in patients referred to a surgical clinic for back pain.

BACKGROUND: We sought to determine the association between radiologic and clinical diagnoses and to measure the impact of more magnetic resonance imaging (MRI) and computed tomography (CT) scans on clinical decision-making in patients referred to a surgical clinic for back pain.
METHODS: We conducted a 7-week prospective study of patients referred for back pain to spine surgeons in 1 health care centre. Patients were included if they had not previously been seen by a surgeon for their back problems and if their back pain was related to the thoracic or lumbar spine. We collected demographic data, imaging findings, clinical diagnoses as determined by the surgeons and visit outcomes and compared our results with those of a similar study conducted in 1996.
RESULTS: Of 160 patients, 8 (5%) were no-shows and excluded from further analysis owing to incomplete data. There were more MRI scans and fewer plain radiographs ordered in 2009 compared with 1996 (73% v. 11% and 39% v. 68%, respectively). Degenerative disc disease was a more common radiologic diagnosis (n=78, 63%) than clinical diagnosis (n=41, 27%). Disc herniation was a more common radiologic diagnosis (n=69, 56%) than clinical diagnosis (n=25, 16%). With regards to visit outcomes, there were fewer second opinions sought in 2009 compared with 1996 (3% v. 11%). Although not statistically significant, the number of surgical candidates remained relatively stable (19% in 1996 v. 16% in 2009, p=0.44).
CONCLUSION: The clinical diagnosis had a poor association with radiologic abnormalities. Despite an increase in the number of MRI and CT scans, the number of patients deemed surgical candidates has not changed.