A cross-sectional study comparing the Oswestry and Roland-Morris functional disability scales in two populations of patients with low back pain of different levels of severity

Study Design. This cross-sectional study compares the Oswestry and Roland-Morris disability scales in two groups of patients with low back pain of different clinical and electromyographic severity. Objectives. To evaluate the correlation between functional disability and diagnoses. Summary of Background Data. There is an increasing need for functional disability measurements to be applied to the evaluation of therapy and outcome in patients experiencing low back pain. Methods. Two very different groups of patients with low back pain completed the Oswestry and Roland-Morris self-administrated functional disability questionnaires. One group included patients presenting with an episode of mechanical low back pain with no clinical radiculopathy. The other group consisted of patients with low back pain and clinical and electromyographic evidence of radiculopathy. Results. Patients diagnosed with low back pain who exhibited signs of radiculopathy on electromyography had a mean score of 49.1 +/- 17.1 on the Oswestry disability questionnaire; a mean score of 33.0 +/- 14.7 was found for patients who experienced ''simple'' low back sprain (with no radiculopathy). This difference was statistically significant (P < 0.0001). On the Roland-Morris questionnaire, the mean score obtained by the group of patients with radiculopathy was 59.1 +/- 21.8 compared with 45.4 +/- 19.4 for those with no radiculopathy. This difference was also statistically significant (P < 0.0001). Moreover, there exists a moderate correlation between both functional scales within each group of patients: 0.72 (P < 0.0001) in the group with radiculopathy and 0.66 (P < 0.0001) among those without radiculopathy. Conclusions. The authors conclude that both functional disability scales accurately discriminated between these two groups of patients with low back pain of very different clinical and electromyographic severity.