1. 2021;24;E625-E629Retrospective Study of the Analgesic Effect of Sacroiliac Joint Radiofrequency Denervation
   Retrospective Study
   Luis A. Borges, MS, Leonardo HC. Ferraro, PhD, Jose L. Campos, MD, Rioko K. Sakata, PhD, and Ligia FT. Kawamoto, MD.

BACKGROUND: Interventional radiofrequency (RF) ablation techniques are indicated when an adequate effect is not obtained with conservative measures.

OBJECTIVES: The primary objective of this study was to evaluate pain relief after RF denervation of the sacroiliac joint. The secondary objective was to evaluate pain intensity and relief duration.

STUDY DESIGN: The study was retrospective.

SETTING: The study was conducted at Vera Cruz Hospital, Campinas, Brazil.

METHODS: Data were collected from the medical records of patients undergoing RF denervation for low back pain originating in the sacroiliac joint, from January 2015 to December 2017. There were 78 patients studied, between 18 and 65 years old, of both genders, ASA I or II, who underwent knee arthroscopic meniscectomy. The patients were submitted to denervation of sacroiliac joint by 3 types of RF (conventional, pulsed, and cooled).

The following parameters were evaluated, number of patients who obtained ? 50% pain relief; pain intensity, measured using the visual analog scale (before the procedure and 15, 30, 90 and 180 days after, performed by the same evaluator); and the use of complementary analgesic for 2 weeks.

RESULTS: Of the 78 included patients, 56 (71.8%) underwent conventional RF, 9 (11.5%) underwent pulsed RF, and 13 (16.7%) underwent cooled RF. There were losses to follow-up including 40 patients who underwent conventional RF, 5 who underwent pulsed RF, and 12 who underwent cooled RF, who were retained for 6 months. There was significant pain relief with the three types of RF for up to 6 months of follow-up, with no difference among the types. After 6 months, 90.2% of patients who underwent conventional RF, 100% who underwent pulsed RF, and 91.7% who underwent cooled RF maintained >= 50% pain relief. Complementary analgesics were used by 95% of the patients who underwent conventional RF, 80% who underwent pulsed RF, and 91% who underwent cooled RF 2 weeks after the procedure. There were mild adverse effects, such as edema, hematoma, and local pain, without complications.

LIMITATIONS: As for limitations, the number of pulsed and cooled RF is low and in a retrospective study some data may be missing, especially from follow-up.

CONCLUSIONS: RF denervation of the sacroiliac joint is effective and promotes a long-lasting analgesic effect.

KEY WORDS: Analgesia, denervation, low back pain, radiofrequency, sacroiliac joint