BACKGROUND This prospective study included 179 patients with degenerative stenosis of the lumbosacral spine and aimed to evaluate the outcomes of conservative treatment and surgical decompression on quality of life and disability over 12 months. MATERIAL AND METHODS The surgery group consisted of 96 patients with degenerative stenosis of the lumbosacral spine who qualified for surgical decompression, while the conservative-treatment group included 83 patients who qualified for conservative treatment. We used the Satisfaction with Life Scale questionnaire, the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F) questionnaire, the Visual Analog Scale to assess the severity of pain, the Oswestry Low Back Pain Disability Questionnaire to assess the degree of disability, and the Sexual Satisfaction Scale at 0, 1, 6, and 12 months after treatment. RESULTS Statistical analysis showed a positive relationship between conservative and surgical treatment and quality of life (P<0.05). A significant reduction in the severity of pain (P<0.05) and the degree of disability (P<0.05) were both recorded during the 12-month followup period in both groups. Women of both groups declared significantly lower satisfaction than men at every time point (P<0.05). CONCLUSIONS Most patients in both groups declared an improvement in their quality of life, with the surgery group showing a higher percentage of responses that their quality of life had improved. Based on the results obtained from the FACIT-F questionnaire, degenerative stenosis of the lumbosacral spine had a non-root effect on the patients' lives in the surgery group.