1. Treatment of Complex Regional Pain Syndrome of the Knee With Peripheral Nerve Stimulation After Failed Dorsal Root Ganglion Stimulation

Abstract

BACKGROUND: Complex regional pain syndrome (CRPS) is a chronic progressive neuropathic condition that generally presents following trauma, surgical procedures, or develop spontaneously. Clinical recommendations are to pursue early, multifactorial treatment modalities, such as physical therapy, psychotherapy, along with medications. If conservative treatment becomes insufficient, interventional treatments, such as dorsal root ganglion (DRG) stimulation and peripheral nerve stimulation (PNS), have been proven effective measures in treating the condition. CASE REPORT: A 44-year-old woman, who underwent multiple knee surgeries originally for osteoarthritis, developed CRPS Type II around her right knee. A L3/L4 DRG stimulator was implanted after conservative treatment failed. She reported 50% improvement and reduced opioid requirement. Symptoms returned due to a L3 DRG lead fracture with an attempted revision. However, postsurgical complications developed: neuroforaminal scarring, which precluded lead replacement and resulted in explantation. A PNS implant was pursued with reported 75% to 80% symptom relief, titration off all medications, and significant return of function. CONCLUSIONS: This case highlights PNS in treating advanced CRPS either as the initial neurostimulator of choice in select populations or as an effective alternative in the event that DRG stimulation or spinal cord stimulation proves ineffective or unfeasible. Here, our patient illustrated favorable results with PNS vs DRG in her CRPS management allowing her to regain her ability to function independently of constant pain and opioids. KEY WORDS: Complex regional pain syndrome, dorsal root ganglion stimulation, peripheral nerve stimulation, case report