Functional restoration for chronic low back pain. Two-year follow-up of two randomized clinical trials.

STUDY DESIGN: Two randomized, prospective clinical trials involving 238 chronic low back disability patients were carried out. Results at 2-year follow-up are presented.

OBJECTIVES: To compare the clinical outcomes of a multidisciplinary functional restoration program with a nontreated control group (Project A) and with two less intensive but different training programs (Project B).

SUMMARY OF BACKGROUND DATA: The effectiveness of functional restoration programs has not been firmly established. Results from trials carried out in the United States differ from those in trials conducted in other countries. Only a few of these studies have been carried out as prospective and randomized clinical studies.

METHODS: Two hundred thirty-eight patients with chronic low back disability of at least 6 months' duration were included. There were 106 patients in project A and 132 patients in project B. Two years after completion of treatment patients were mailed a questionnaire that included questions regarding their work status, pain and disability levels, number of sick leave days, number of medical care contacts, medication use, physical activity levels, and subjective overall assessment of their "back life situation."

RESULTS: Patients in both studies were comparable at inclusion, except that patients in Project A were recruited from all of Denmark, whereas those in Project B were from the greater Copenhagen area. Thirteen patients did not report for treatment after randomization. Of the remaining 225 patients, 20 (9%) did not complete treatment. The questionnaire response rate was 94%. In Project A, those patients receiving treatment (functional restoration) reported significantly less contact with the health care system, fewer sick leave days, and a less disabled life style during the follow-up period, compared with reports of patients in the control group. Other effect parameters did not demonstrate a significant difference between the two groups. In Project B, all effect parameters reported, except leg pain and medication usage, were significantly in favor of functional restoration, compared with reports from the less intensively treated groups.

CONCLUSIONS: The functional restoration program seems effective in various parameters compared with the less intensive programs, but the differences in outcome in the two parallel studies indicate the necessity of testing a treatment program in different settings, in that the statistical variation may be a major factor in results of different studies.