Clinical Report: Chemical Neurolysis of Genicular Nerves for Chronic Knee Pain

Overview

This scoping review of eight studies involving 192 patients demonstrates that chemical neurolysis of genicular nerves using phenol or alcohol improves pain and function in chronic non-cancer knee pain without serious adverse events. The evidence is limited by small sample sizes and heterogeneity in techniques and outcomes.

Background

Knee osteoarthritis affects nearly 23% of adults over 40, with many patients unsuitable for or refractory to total knee arthroplasty. Genicular nerve denervation offers a nonsurgical alternative for pain relief. Chemical neurolysis, involving agents like alcohol or phenol, targets genicular nerves under image guidance but remains less studied than radiofrequency ablation. This review synthesizes current evidence on its effectiveness, safety, and procedural approaches.

Data Highlights

Key Findings

• Chemical neurolysis with phenol or alcohol consistently improved pain and functional outcomes in chronic knee pain patients.
• No serious adverse events were reported across all included studies.
• Image guidance techniques varied, including fluoroscopy, ultrasound, or a combination, with no consensus on optimal modality.
• Genicular nerve targets and neurolytic agent dosages were heterogeneous across studies.
• Evidence is limited by small sample sizes and only one randomized controlled trial included.
• Further high-quality RCTs are needed to determine optimal nerve targets, agents, and comparative effectiveness versus other ablative methods.

Clinical Implications

Chemical neurolysis of genicular nerves represents a promising nonsurgical option for patients with chronic non-cancer knee pain, especially those unsuitable for surgery. Clinicians should consider image-guided phenol or alcohol neurolysis as a safe intervention with demonstrated pain relief, while recognizing the current evidence limitations. Careful patient selection and procedural planning are essential pending further research.

Conclusion

Chemical neurolysis of genicular nerves is an effective and safe treatment modality for chronic knee pain, though current evidence is preliminary. Larger, well-designed trials are required to optimize techniques and confirm long-term benefits.

References

1. Interventional Pain & Spine Medicine Section, 2023 -- A Scoping Review of Chemical Neurolysis for Genicular Nerves in Managing Chronic Non-Cancer Knee Pain