The Antinociceptive Effect of Genicular Nerves Block Compared to Intra-Articular Dexamethasone in Grade III or IV Knee Osteoarthritis

Abstract

Introduction: Knee pain secondary to osteoarthritis is a common pathology reflecting on the capacity of undertaking daily activities. Among non-surgical procedures, intra-articular corticosteroids represent an alternative complementary therapy. However, blocking the genicular nerves is a recently described technique, easily applied for clinical management. Objectives: To compare efficacy of both intra-articular corticosteroid and genicular block for chronic knee pain. Methods: 20 patients with osteoarthritis were evaluated for: 1) the intensity of pain; 2) the quality of sleep; 3) the capacity to undertake daily activities. Two groups were formed randomly, the first submitted to intra-articular blocking and the second to blocking the genicular nerves. A solution of plane 90 mg lidocaine 1%, and dexamethasone 10 mg was standard and used for intervention in both procedures to a final 10-ml volume. After a weekly appraisal for 12 consecutive weeks, the patients were recalled and submitted to another proposed procedure and in this way, all the patients acted as their own control (a “crossover” study design). In the following weeks, as also in the pretest, the intensity of pain, the quality of sleep and the capacity of undertaking daily activities were evaluated. Results: Both the intra-articular block and the genicular nerves block resulted equally in important reduction of pain during 11 weeks, with similar improvement in the quality of night sleep, and in the capacity of daily activities (p < 0.05). Conclusions: The blocking of the genicular nerves was a safe alternative, minimally invasive and highly efficient, similar to the intra-articular corticosteroid.