1999 Volvo Award Winner in Clinical Studies

STUDY DESIGN: A randomized clinical trial. OBJECTIVES: To examine the relative efficacy of three active therapies for chronic low back pain. SUMMARY OF BACKGROUND DATA: There is much evidence documenting the efficacy of exercise in the conservative management of chronic low back pain, but many questions remain regarding its exact prescription and method of application. The most successful method must be identified to enable refinement of future rehabilitation programs to target the specific needs of the patient with chronic low back pain and the budget of the healthcare provider. METHODS: One hundred forty-eight patients with chronic low back pain were randomized to one of the following treatments, which they attended twice a week for 3 months: 1) modern active physiotherapy, 2) muscle reconditioning on training devices, or 3) low-impact aerobics. Pretherapy and posttherapy, objective measurements of lumbar mobility were performed, and questionnaires were administered inquiring about self-rated pain and disability, and psychosocial factors. Similar questionnaires were administered 6 months after therapy. The data were analyzed using the intention-to-treat principle. RESULTS: Of the 148 patients, 16 (10.8%) dropped out of the therapy. One hundred thirty-seven questionnaires (93%) were available for analysis at all three time points. After therapy, significant reductions were observed in pain intensity, frequency, and disability; Fear-Avoidance Beliefs about physical activity (FABQactivity); and "praying/hoping," "catastrophizing," and "pain behavior" coping strategies--each with no group differences in the extent of the response. These effects were maintained over the subsequent 6 months, with the exception of disability and FABQactivity for the physiotherapy group. There were small but significant posttherapy increases in lumbar mobility, with aerobics and devices showing a greater response than physiotherapy. CONCLUSION: The general lack of treatment specificity suggests that the main effects of the therapies were educed not through the reversal of physical weaknesses targeted by the corresponding exercise modality, but rather through some "central" effect, perhaps involving an adjustment of perception in relation to pain and disability. The direct costs associated with administering physiotherapy were three times as great, and devices four times as great, as those for aerobics. Administration of aerobics as an efficacious therapy for chronic low back pain has the potential to relieve some of the huge financial burden associated with the condition.