Genicular nerve neurolysis (GN) constitutes a relatively novel technique, whereby different chemical compounds (i.e. alcohol, phenol) are injected in close proximity to the genicular nerves of the knee joint, with the intention to exert a neurolytic effect by denaturing proteins resulting in Wallerian degeneration distal to the lesion. Based on the preliminary evidence and considering the potential benefits of the technique, we hypothesized that ultrasound-guided genicular chemical neurolysis with phenol is superior in terms of pain relief at 3 months, when compared to intra-articular steroid (IAS) injection.

This study will allow us to determine if ultrasound-guided phenol genicular neurolys is superior to intra-articular steroid injection in terms of analgesia and functional outcomes, providing a more effective and long-lasting alternative for patients with chronic knee pain secondary to osteoarthritis

Inclusion Criteria:

• Severe knee pain for more than 6 months, defined as Numeric rating scale (NRS) score of 6 and greater, unresponsive to conservative medical treatment
• Radiological OA grade 2 to 4 (Kellgren-Lawrence scale)

Exclusion Criteria:

• Previous total knee replacement on the index knee
• Prior knee radiofrequency ablation on the index knee
• Connective tissue diseases with knee involvement (e.g. rheumatoid arthritis)
• Body mass index ≥ 40 kg/m2
• Uncontrolled coagulopathy, defined as supratherapeutic dose of anticoagulation medication
• Allergy to local anesthetics
• Unstable opioid consumption, defined as an increase >10% in dosage during the last 3 months prior to recruitment.