Efficacy of Genicular Nerve Block in Patients with Osteoarthritis: A Comparative Study with and without Fluoroscopy Assistance.

To compare the efficacy of fluoroscopy as an auxiliary method in genicular nerve block (GNB) with block guidance by anatomical parameters, without imaging aid, in reducing pain.  A total of 23 patients underwent fluoroscopy-guided or anatomical parameter-based GNBs. We applied the Western Ontario and McMaster Universities' Osteoarthritis Index (WOMAC) and the Visual Analog Scale (VAS) for pain at 6 time points (preblock, and after 1 hour, 24 hours, 7 days, 28 days, and 90 days).  The mean age of the sample was of 64.5 ± 4.8 years, and the mean Body Mass Index (BMI), of 31.4 ± 6.1 Kg/m ; 16 subjects (69.6%) were women. The WOMAC pain subscale showed a significant reduction (  < 0.05) in pain in both groups at all time points. This reduction was greater after 1 hour in both groups, with rates if 64.3% and 64.6% in the fluoroscopy and anatomical parameters groups respectively, with no significant difference. At the end of 90 days, the pain reduction rates were of 35.7% and 44.6% in the fluoroscopy and anatomical parameter groups respectively. The VAS also showed a significant reduction (  < 0.05) in pain in both groups at all times. The reduction was more significant after 1 hour: 78.0% in the fluoroscopy group and 82.2% in the anatomical parameter group, with no significant difference. At the end of 90 days, the pain reduction was of in the fluoroscopy group 36.5% and of 24.6% in the anatomical parameters group.  The GNBs guided by fluoroscopy or by anatomical parameters alone were equally effective in terms of magnitude and duration of pain relief.