US-Guided Saphenous Block in Knee OA (SAPH-KNEE-OA)

The purpose of this prospective, randomized, open-label, active-controlled clinical trial is to evaluate the clinical and sonographic effects of ultrasound-guided (US-guided) high-volume saphenous nerve block combined with intra-articular corticosteroid injection compared to intra-articular corticosteroid injection alone in patients with Kellgren-Lawrence Grade 3-4 medial compartment knee osteoarthritis (OA) refractory to conservative treatment. A total of 60 participants aged 45-75 years will be randomly assigned (1:1) into two treatment arms: * Group 1: US-guided intra-articular corticosteroid injection (40 mg triamcinolone acetonide + 1 mL saline) + home exercise program. * Group 2: US-guided intra-articular corticosteroid injection + US-guided high-volume saphenous nerve block (10 mL 0.2% bupivacaine solution) + home exercise program. Clinical assessments (WOMAC, VAS, and SF-36) will be conducted at baseline (T0), 1st month (T1), 3rd month (T2), and 6th month (T3). Sonographic evaluations, including saphenous nerve cross-sectional area (CSA) and perineural vascularity via…

• Change in Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) Total Score
• Change in Visual Analog Scale (VAS) Pain Score

1. Study completion expected

   Nov 30, 2027

2. Primary completion expected

   Apr 30, 2027

3. Registered

   Oct 9, 2026

4. Started

   Oct 2, 2026