The Effect of Therapeutic Methods for Chronic Knee Osteoarthritis Pain

Chronic osteoarthritis (OA) pain of the knee is not effectively abrogated by the available non-pharmacologic or pharmacologic treatments. Radiofrequency (RF) neurotomy is a therapeutic alternative for chronic pain. Here, the researchers investigate the efficacy of RF neurotomy applied to articular branches (genicular nerves) in treating knee joint pain.

The knee joint is innervated by articular branches of various nerves (femoral, common peroneal, saphenous, tibial and obturator) (Kennedy et al. 1982; Hirasawa et al. 2000). These articular branches around the knee joint are known as genicular nerves. Several genicular nerves can be easily approached percutaneously under fluoroscopic guidance. In our study, genicular nerves were effectively blocked with local anesthetics under fluoroscopic guidance, leading to a significant reduction in knee pain. Rf neurotomy is based on the theory that cutting the nerve supply to a painful structure may alleviate pain and restore function. we evaluate the efficacy of RF neurotomy in reducing pain and improving function in the elderly with chronic knee OA.

After lidocaine injection through the RF cannula, the temperature of the electrode tip was raised to 70℃ for 90 seconds by RF generator.

RF cannula was advanced percutaneously towards areas connecting the shaft to epicondyle of femur or tibia. Lidocaine (1 mL of 2%) was injected before activation of the RF generator (NeuroThermTM, Morgan automation LTD, Liss, UK). RF electrode was inserted through RF cannula. The temperature of the electrode tip was raised to 70℃ for 90 seconds by radiofrequency generator.

Inclusion Criteria: patients with chronic knee pain (i.e., knee pain of moderate intensity or greater on most or all days for ≥ 3 months) patients with radiologic knee osteoarthritis (Kellgren-Lawrence grade 2-4, evaluated by a radiologist) Exclusion Criteria: acute knee pain prior knee surgery other connective tissue diseases affecting the knee serious neurologic or psychiatric disorders injection with steroids or hyaluronic acids during the previous 3 months sciatic pain anticoagulant medications pacemakers prior electroacupuncture treatments

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