Peripheral Nerve Stimulation with a High Frequency Electromagnetic Coupled (HF-EMC) Powered Implanted Neurostimulator with Receiver at the Suprascapular and Supraclavicular Nerves for the Treatment of Chronic Shoulder Pain: Case Report

Abstract

Background: Over 20% of adults are affected by chronic shoulder pain that can limit the use of the upper extremity and decrease the overall quality of life. Peripheral nerve stimulation (PNS) is an emerging treatment for refractory cases of chronic pain that has been receiving heightened attention in recent years with growing documentation of favorable results. This report discusses a case of chronic shoulder pain effectively managed with PNS. Case Report: A 58-year-old man, with a history of cervical laminectomy presented with persistent pain of the left shoulder, radiating down the medial aspect of the left upper arm to the elbow, and pain along the upper trapezius between the neck and shoulder that did not ease after successful shoulder joint replacement. The pain averaged 8/10 and escalated to 10/10 with arm movement or lifting over 5 pounds. Once agitated, the pain would stay elevated for several hours. The patient eventually withdrew completely from social activities and stopped leaving his home except when absolutely necessary to avoid additional pain brought on by activity. Previous treatments, including physical therapy, opioids, nonsteroidal anti-inflammatory drugs (NSAIDS), and cervical epidural steroid injection, were unsuccessful in managing pain. The patient did, however, achieve relief with peripheral nerve stimulation. Pain scores at 3-month follow-up decreased from 8/10 without and 10/10 with activity to an average of 1/10 with increased activity, complete cessation of pain medication, and reported improvement in quality of life. These results have been maintained at 12 months post-implant. Conclusion: Sub-threshold peripheral nerve stimulation with an externally powered system at the suprascapular and supraclavicular nerves was an effective treatment for a patient suffering from debilitating pain in the shoulder, upper arm, and upper trapezius after a successful, structurally sound shoulder replacement did not reduce persistent chronic pain. Key words: Peripheral nerve stimulation (PNS), chronic pain, suprascapular nerve, supraclavicular nerve, mononeuropathy, upper limb pain, brachial plexus, disorder, shoulder replacement