Assessment of ultrasound-guided continuous genicular nerve radiofrequency for the management of persistent post-arthroplasty knee pain.

Abstract

To evaluate the efficacy of continuous ultrasound-guided genicular nerve radiofrequency (GNRF) for managing persistent post-arthroplasty knee pain of unknown etiology. In this single-center retrospective study, patients presenting with chronic knee pain following total knee arthroplasty, with no identifiable underlying cause and unresponsive to conventional treatments, underwent ultrasound-guided diagnostic nerve blocks followed by continuous GNRF targeting the supero-medial, supero-lateral, and infero-medial genicular nerves. Pain scores using a numeric rating scale (NRS) were assessed and compared at baseline, 1 month, and 6 months. The correlation between anesthetic nerve block test results and treatment efficacy was also analyzed. Twenty-three patients (mean age 69.9 ± 12.1 [SD], 9 men) were included between December 2021 and April 2024. At 1 month, the mean NRS score decreased from 8.0 ± 1.4 to 6.0 ± 3.4 [SD] (p = 0.01). Clinically significant pain reduction (≥ 2-point decrease) was observed in 47.8% of patients; 34.8% achieved a ≥ 50% reduction. At 6 months, the mean NRS score was 6.6 ± 3.0 [SD], with no statistically significant difference compared to baseline and 1-month NRS scores. No significant correlation was found between nerve block test outcomes and GNRF efficacy. No major complications were reported. Continuous ultrasound-guided GNRF appears to be a safe and effective minimally invasive option for chronic post-arthroplasty knee pain with no known underlying etiology. Question Persistent post-arthroplasty knee pain with no identified underlying etiology is frequent and often difficult to manage with conventional therapies. Findings Ultrasound-guided continuous GNRF provides clinically significant pain relief at 1 month and up to 6 months. Clinical relevance Prognostic nerve blocks did not correlate with radiofrequency outcomes.