RESUMO
BACKGROUND: The number of patients undergoing lumbar spinal fusion procedures (LSF) has risen in recent years, but only few studies have examined different rehabilitation strategies for this patient group. PURPOSE: To evaluate the impact of initiating rehabilitation either 6 or 12 weeks after a LSF based on the patients' physical performance using the 6-min walking test (6MWT) and the Åstrand Fitness test (AF-test) as measurement. METHODS: A multicentre RCT including 82 patients with degenerative disc diseases undergoing LSF randomly assigned to initiate rehabilitation either 6 or 12 weeks after surgery. Both groups received the same group-based rehabilitation. The main outcome measures were the 6MWT and the AF-test, secondarily questionnaire-based measures. Follow-up at baseline as well as at 3, 6 and 12 months after surgery. RESULTS: Comparing the two groups no statistically significant difference was found in walking distance or fitness over time. In both groups, the patients achieved an overall increase in walking distance (p < 0.01), but no improvement in fitness. The 6MWT showed significant correlation (-0.37 to -0.59) with the questionnaire-based outcome measures (p < 0.01). The AF-test did not correlate to either the 6MWT or any of the questionnaire-based outcome measures. CONCLUSION: No difference was found in the effect of initiating rehabilitation either 6 or 12 weeks after LSF on the patients' physical performance in terms of fitness and walking distance. The 6MWT showed fair to moderate correlation to the questionnaire-based outcome measures. The AF-test showed no significant independent value, and we question its use in LSF patients.