Routine versus needs-based MRI in patients with prolonged low back pain: a comparison of duration of treatment, number of clinical contacts and referrals to surgery.

Abstract

Background: The routine use of radiology is normally discouraged in patients with low back pain (LBP). Magnetic Resonance Imaging (MRI) provides clinicians and patients with detailed knowledge of spinal structures and has no known physical side effects. It is possible that insight into the pathological changes in LBP patients could affect patient management. However, to our knowledge, this has never been tested. Until June 2006, all patients at our specialised out-patient public clinic were referred for MRI on the basis of clinical indications, economic constraints, and availability of MRI (the "needs-based MRI" group). As a new approach, we now refer all patients who meet certain criteria for routine up-front MRI before the clinical examination (the "routine MRI" group).

Objectives: The aims of this study were to investigate if these two MRI approaches resulted in differences in: (1) duration of treatment, (2) number of contacts with clinicians, and (3) referral for surgery.

Design: Comparison of two retrospective clinical cohorts.

Method: Files were retrieved from consecutive patients in both groups. Criteria for referral were: (1) LBP or leg pain of at least 3 on an 11-point Numeric Rating Scale, (2) duration of present symptoms from 2 to12 months and (3) age above 18 years. A comparison was made between the "needs-based MRI" and "routine MRI" groups on the outcomes of duration of treatment and use of resources.

Results: In all, 169 "needs-based MRI" and 208 "routine MRI" patient files were identified. The two groups were similar in age, sex, and severity of LBP. However, the median duration of treatment for the "needs-based MRI" group was 160 versus 115 days in the "routine MRI" group (p = 0.0001). The median number of contacts with clinicians for the "needs-based MRI" group was 4 versus 3 for the "routine MRI" group (p = 0.003). There was no difference between the two approaches in frequency of referral for back surgery (p = 0.81). When the direct clinical costs were compared, the "routine MRI" group was less costly but only by euro11.

Conclusion: In our clinic, the management strategy of routinely performing an up-front MRI at the start of treatment did reduce the duration of treatment and number of contacts with clinicians, and did not increase the rate of referral for back surgery. Also, the direct costs were not increased.