Background and Study Aims Low back pain is well documented as an extremely common health problem. The most frequently used treatment is radiofrequency denervation for chronic low back pain. However, different clinical studies could only show a limited to no improvement regarding the decrease of pain intensity and duration of the effect. The main reasons for these limited effects seem to be due to the size of the lesion and difficulties in locating the exact placement of the cannula near the medial branch as well as or additional pathologies. Using an endoscope, it is possible to coagulate the facet joints and the medial branch under visual control and consider other pathologies such as extraspinal synovial cysts. Patients In this retrospective study, we included 28 patients with low back pain, with a duration > 6 months and a 50% pain reduction on the numeric analog scale (NAS) after a diagnostic block. All patients received endoscopic facet joint denervation of three facets on the left and right side using only one incision on each side with an exploration of the surrounding tissue. Telephone interviews were conducted with all patients. The outcome was determined with Odom's criteria, percentage reduction NAS, subjective assessment of the patient, and duration of the effect. Results According to Odom's criteria, 68% of the patients showed “acceptable” to “excellent” results and confirmed that denervation helped them manage their daily lives better. The average pain reduction in the responder group was 47% with an average duration of 7.8 months. Conclusion In this retrospective study, we demonstrated the practicability and effectiveness of the endoscopic facet joint denervation procedure in the treatment of chronic low back pain using only one incision for three facets. Further studies should investigate if this procedure is more effective than percutaneous radiofrequency denervation.

Background and Study The sacroiliac joint (SIJ) may be the primary source of pain in 15 to 25% of patients with axial low back pain. Furthermore, 75% of patients who have had fusion surgery develop SIJ pain within 10 years. Treatment options include SIJ blocks, radiofrequency (RF) denervation, and fusion. The RF techniques range from ablation of the nerves supplying the joint, creating lesions to the joint itself, or a combination of both techniques. However, different clinical studies could only identify a limited or, in some cases, no effect in decreasing of pain intensity and duration of the effect. Methods In this retrospective study, we selected 23 patients with SIJ pain, with a duration of more than 12 months and a 50% pain reduction on the Numeric Rating Scale (NRS) after diagnostic block. All patients received endoscopic ablation of the medial branch L5/S1 and the lateral branches, exiting the sacral foramina on S1/S2 and S2/S3 on both sides while using only one incision on each side. Telephone interviews were conducted with all patients. The outcome was determined with Odom's criteria, percent reduction NRS, subjective assessment of the patient, and duration of the effect. Results According to Odom's criteria, 79% of the patients showed acceptable to excellent results and confirmed that denervation helped them to manage their daily lives better. The average pain reduction in the responder group was 57% with an average duration of 13.4 months. Conclusion In this retrospective study, we could demonstrate the practicability and effectiveness of endoscopic SIJ denervation in the treatment of SIJ pain using only one incision for three levels on each side. Further studies should investigate if this procedure is more effective than percutaneous RF.