Comparison of the Effects of Phenol Neurolysis and Conventional Radiofrequency Thermocoagulation Applied to the Genicular Nerves on Pain in Patients Who Underwent Knee Arthroplasty: A Prospective, Controlled Study
Devran Ertilav, Esra ErtilavAbstract
Objective
This study aimed to compare conventional radiofrequency thermocoagulation (RFT) with chemical neurolysis in patients who underwent knee arthroplasty and continued to experience pain.
Materials and Methods
This was a prospective, quasi-randomized controlled trial. A total of 109 patients who underwent knee arthroplasty were evaluated and assigned to two groups according to the interventional procedures applied to the genicular nerves: Group 1 included patients who underwent conventional RFT, and Group 2 included patients who underwent chemical neurolysis of the genicular nerves using phenol. The Numeric Rating Scale (NRS) and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) were used to assess pain intensity before the procedure and at 1, 3, and 6-month follow-ups.
Results
The demographic and clinical characteristics were similar between the conventional RFT and phenol groups. At one month, the mean NRS was 4.09±0.73 in the RFT group and 3.67±0.73 in the phenol group, significantly lower in the phenol group (p = 0.015)[d = 0.503; 95% CI]. The mean NRS scores were 5.57±0.81 and 4.64±0.75, respectively, at the third month (p < 0.001)[d:1.195 95%CI], and 6.52±1.38 and 5.02±1.46 at the sixth month (p < 0.001)[d:1.055 95%CI]. At three months, the NRS ≥50% improvement rate was 29.6% in the RFT group and 49.1% in the phenol group, with a significant difference in favor of the phenol group (p = 0.038)[OR:2.290 95% CI]. At six months, the NRS ≥50% improvement rate was 18.5% and 43.6%, respectively, and the difference was statistically significant in favor of the phenol group (p = 0.005)[OR:3.406 95% CI]. NRS≥30% improvement rate was similar at 1 month, at 98.1% in the RFT group and 98.2% in the phenol group (p = 1.000)[OR: 1.019 95% CI]. At three months, these rates were 83.3% and 90.9%, respectively, with no statistically significant difference (p = 0.237)[OR: 2.000 95% CI]. At six months, NRS ≥30% improvement was observed in 72.2% of the RFT group and 87.3% of the phenol group, with a borderline statistically significant difference (p = 0.050)[OR: 2.637 95% CI]. The complication rate was 3.7% in the RFT group and 5.5% in the phenol group, with no significant difference between the two groups (p = 1.000) [OR: 1.500 95% CI].
Conclusion
Phenol neurolysis and conventional RFT of the genicular nerves are effective treatments for patients with persistent pain after knee arthroplasty. The results demonstrating the short-term efficacy of phenol neurolysis in patients undergoing arthroplasty should be supported by long-term follow-up studies.