1000 Section - The effectiveness of phenol neurolysis of the genicular nerves to treat refractory knee pain: a prospective cohort study.

Genicular nerve radiofrequency ablation (GRFA) is an effective treatment for knee osteoarthritis–related pain, but it can be painful and time-intensive. Phenol neurolysis achieves analgesia through chemo-denervation and interruption of nociceptive signaling and may offer reduced procedural discomfort; however, the effectiveness of phenol genicular neurolysis (PGN) has not been well studied. The objective of this study was to evaluate the effectiveness of PGN in patients with painful knee OA.

Design:

This single-arm cohort study included participants treated with PGN at a single Canadian musculoskeletal clinic from November 2024 to December 2025. Participants were selected after achieving ≥ 50% relief following a single round of genicular nerve blocks and subsequently underwent PGN of at least the superolateral, superomedial, and inferomedial genicular nerves using established fluoroscopic landmarks. All participants completed Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) questionnaires at baseline and 12 weeks following the procedure. Outcomes were the proportion of participants who experienced a Minimally Clinically Important Difference (MCID) on WOMAC subscales and totals scores.

Results:

Of the 77 participants, 41 (53%; 95% CI = 42-64), 33 (43%; 95% CI = 32-54), 40 (52%; 95% CI = 41-63), and 41 (53%; 95% CI = 42-64) met MCID for total WOMAC, WOMAC pain, WOMAC stiffness, and WOMAC physical function, respectively.

Conclusion:

Phenol genicular neurolysis resulted in clinically meaningful improvements in pain, stiffness, and physical function (on WOMAC) in approximately 50% of participants at 12 weeks when selected based on ≥ 50% relief following single genicular nerve anesthetic blocks. Larger, long-term studies comparing the effectiveness of PGN with GRFA are needed.