Objectives: To investigate the effectiveness of small joint radiofrequency ablation in the treatment of low back pain due to osteoarthritis of the facet joints in the lumbar and lumbosacral spine. Success will be defined by examining pain intensity using the VAS scale. Study design: The study is a cross-sectional study with historical data. Participants and methods: The study included 34 patients treated at the Clinic for Orthopaedics and Traumatology of the University Hospital Centre Osijek (KBC Osijek) for low back pain due to facet joint osteoarthritis using the method of radiofrequency ablation of small joints. The general patient data were taken from the medical records: Age, gender and localization of facet joint osteoarthritis. In addition to the clinical examination, data on the level of pain were collected by means of a questionnaire completed by the patients before and after the therapeutic procedure. Results: The research results show that both genders are equally affected by low back pain due to facet joint osteoarthritis. Most of the patients felt pain on the left side of the lumbosacral part of the spine, namely 17/34 of them, while the least of them felt pain on both sides, namely 8/34 of them. The spinal level most frequently affected by osteoarthritis was L4 – L5, in 13/34 patients. The statistical data before and after the therapeutic procedure prove the success of the method of radiofrequency ablation of small joints. The median pain score before the therapeutic procedure was 8 (8 – 9 interquartile range) and after the procedure 3 (1,5 – 3) measured on the VAS scale. Conclusion: The use of small joint radiofrequency ablation in the treatment of low back pain due to facet joint osteoarthritis resulted in a significant reduction in pain.