Wearable Pulsed Electromagnetic Fields Device in Knee Osteoarthritis: Double Blinded, Randomized Clinical Trial

Inclusion Criteria: * a diagnosis of primary OA of the knee according to the ACR criteria, including radiologic evidence of OA * age \>40 years * symptomatic disease for at least 6 months prior to enrollment * persistent pain despite receiving the maximum tolerated doses of conventional medical therapy, including acetaminophen (4 gm/day) and/or a nonsteroidal antiinflammatory drug (NSAID), with persistent pain defined as a minimum mean score of 25 mm on the visual analog scales (VAS) for global pain (0-100-mm range for each) daily pain during the month prior to study enrollment * ability to attend followup appointments Exclusion Criteria: * secondary causes of OA * local or systemic infection * diabetes mellitus * systemic arthritis * allergy to anesthetic agent or contrast material * coagulopathy * anticoagulant therapy * had previous IA steroid injection * avascular necrosis of bone * patients who are on specific OA pharmacological therapy (NSAIDS, opioids) for more than 2 weeks prior enrollment