Effect of ultrasound-guided genicular nerve block in knee osteoarthritis with neuropathic pain

Introduction: Osteoarthritis (OA) remains one of the most common musculoskeletal disorders. It was thought to be a non-inflammatory, wear and tear disorder, but recent studies have suggested the presence of a neuropathic pain component. Genicular nerve block has emerged as a new intervention to manage the neuropathic component of pain in knee OA. Materials and Methods: We conducted a prospective, hospital-based descriptive interventional study. Persons having OA with neuropathic pain component were identified using PainDETECT scale. We randomised the participants meeting the inclusion criteria into two groups. In the study group with thirty participants, we performed an ultrasound-guided triple-site genicular nerve block. The control group of equal size underwent conservative management. Participants were assessed using PainDETECT scale, Visual analogue scale (VAS) and Western Ontario McMaster Universities Arthritis Index (WOMAC) at baseline, 2 weeks and 4 weeks. Results: In the study group, PainDETECT score decreased from 24.93 ± 1.99 at baseline to 8.07 ± 2.97 at 2 weeks and 7.9 ± 2.87 at 4 weeks. WOMAC significantly improved in the study group from 94.27 ± 8.35 to 48.43 ± 10.14 at 4 weeks. VAS score also decreased in the study group from 9.2 ± 0.71 to 4.73 ± 1.44 at 2 weeks and 4.53 ± 1.28 at 4 weeks. The control group also showed a significant decrease in PainDETECT score from 24.13 ± 1.17 to 12.07 ± 1.36 at 4 weeks. However, a decrease in VAS score (from 9.13 ± 0.68 to 7.67 ± 0.67 at 4 weeks) and WOMAC (from 97 ± 4.49 to 88.5 ± 4.93 at 4 weeks) was less significant. Conclusion: Genicular nerve block provides significant pain relief and improved functional outcome in OA knee with neuropathic pain component. Furthermore, it is more effective than conservative management.