Objective To compare pain, function, quality of life and adverse events of lumbar decompression and spinal fusion in patients with degenerative spinal pathologies who participated in a second opinion program for spinal surgeries with a 36-month follow-up. Methods The data for this retrospective cohort were withdrawn from a private healthcare system between June 2011 and January 2014. The study sample consisted of 71 patients with a lumbar spine surgical referral. The outcomes for the comparisons between lumbar decompression and spinal fusion were quality of life (evaluated through the EuroQoL 5D), pain (measured by the Numerical Rating Scale) and function (assessed through the Roland Morris Disability Questionnaire) measured at baseline, and at 12 and 36 months after the surgical procedures. The definitions of recovery were established by the minimal clinically important difference (MCID). The baseline differences between the groups were analyzed by non-paired t -test, and the differences in instrument scores between time points, by generalized mixed models. The results were presented as mean values adjusted by the models and 95% confidence intervals. Results Concerning the surgical techniques, 22 patients were submitted to spinal fusion and 49 patients, to lumbar decompression. As for the comparisons of the findings before and after the surgical interventions, the MCID was achieved in all outcomes regarding quality of life, pain and function at both time points when compared to baseline scores Moreover, concerning the complication rates, only lumbar decompression presented a surgical rate of 4% ( n = 3) for recurrence of lumbar disc hernia. Conclusion Patients with degenerative spinal pathologies present improvements in long-term outcomes of pain, function and quality of life which are clinically significant, no matter the surgical intervention.