The influence of the grade of chronicity on the outcome of multidisciplinary therapy for chronic low back pain

Study Design. Prospective longitudinal clinical study. Objective. The objective of the study was to analyze the outcome of different stages of chronicity in patients with chronic low back. pain treated with a multidisciplinary therapy. Summary of Background Data. Results of studies comparing different grades of chronicity in therapy for chronic low back pain have not been published so far. Methods. A total of 387 patients with chronic low back pain for 3 months or longer and a corresponding sick leave for longer,than 6 weeks underwent a 3-week standardized multidisciplinary therapy. At baseline (T0), patients were assigned into 3 groups of chronicity grades according to the classification of von Korff et al (Group A, Grades I and II; Group B, Grade III; Group C, Grade IV) and were prospectively followed. At the the 6-month follow-up (T1), 5 different therapy outcomes were analyzed and compared in the 3 groups: back-to-work status, generic health status (SF-36), pain intensity (visual analogue scale), functional capacity (Hannover back capacity score), and satisfaction with the therapy. Results. At TO, patients in Group C had a higher pain level, a longer history of pain, and more general and more psychosomatic comorbidities than patients with lower levels of chronicity. All 3 treatment groups improved significantly in all outcome criteria between T0 and T1. In the total group, the back-to-work rate was 67.4%. At the final follow-up, there were significantly better results in terms of functional capacity and pain level in patients with lower grades of chronicity but mostly due also to worse initial baseline values. Back-to-work rate, satisfaction with therapy, and the Mental Component Summary of the SF-36 did not show a significant difference at T1 between the groups analyzed. Conclusion. According to the results of this study, patients with chronic low back pain also derive significant benefit from a multidisciplinary treatment strategy in higher stages of chronicity. Therefore, therapy should not be limited to the patients in lower stages of chronicity.