Study design: A randomized controlled study of percutaneous radiofrequency neurotomy was conducted in 40 patients with chronic low back pain (20 active and 20 controls).
Objective: The aim of the study was to evaluate the possible beneficial effect of percutaneous radiofrequency zygapophysial joint neurotomy in reducing pain and physical impairment in patients with pain from the lumbar zygapophysial joints, selected after repeated diagnostic blocks.
Summary of background data: Facet or zygapophysial joint pain may be one of the causes of chronic low back pain and may be treated by a percutaneous radiofrequency denervation. Patients may possibly be identified by a positive diagnostic block. These blocks need to be repeated as false positive responses to single blocks occur.In all previous studies patients treated with radiofrequency denervation have been selected after single diagnostic blocks resulting in a varying degree of relief.
Methods: All patients were examined by an orthopedic surgeon before and 6 months after the treatment (sham or active). Inclusion criteria were 3 separate positive facet blocks. Denervation was achieved by multiple lesions at each level in an effort to provide effective denervation.
Results: The active treatment group showed statistically significant improvement not only in back and leg pain but also back and hip movement as well as the sacro-iliac joint test. Pre operative sensory deficit and weak or absent ankle reflex normalized (P < 0.01) and (P < 0.05), respectively. There was significant improvement in quality of life variables, global perception of improvement, and generalized pain.The improvement seen in the active group was significantly greater then that seen in the placebo group with regard to all the above-mentioned variables. None of our patients had any complication other than transient postoperative pain that was easily managed.
Conclusion: Our study indicates that radiofrequency facet denervation is not a placebo and could be used in the treatment of carefully selected patients with chronic low back pain.