Postamputation Pain

Introduction

It is estimated that there are currently 2 million amputees living in the United States, with nearly half of these patients suffering from postamputation pain (PAP). With approximately 185,000 new amputations occurring each year, the number of amputees is expected to rise to over 3.5 million by 2020, with a corresponding increase in the incidence of PAP. Amputation permanently alters nearly every aspect of the lives of amputees, and PAP is for many amputees the most significant sequela following amputation, potentially leading to impaired function, decreased quality of life, and depression. The two major causes of PAP are residual limb pain (RLP) and phantom limb pain (PLP). Unfortunately, there is no defined standard of care for PAP, and traditional treatment of PAP has consisted of a combination of physical and occupational therapy, psychological therapy, mirror box rehabilitation, medications (including but not limited to nonsteroidal antiinflammatory drugs [NSAIDs], acetaminophen, opioids, gabapentinoids, antiepileptics, serotonin-norepinephrine reuptake inhibitors, and ketamine infusions), spinal cord stimulation (SCS), intrathecal pump implantation, and surgical resection of peripheral neuromas, all with inconsistent results. Peripheral nerve stimulation (PNS) has long been recognized as an effective treatment for PAP; however, previous methods of PNS were based off SCS, requiring surgical implantation and lead placement, and were frequently complicated by poor lead placement, lead migration, or infection, often requiring reoperation. The invasiveness and overall risk have traditionally made these methods of PNS less practical. Recent studies, however, have shown that percutaneous PNS may be an effective, minimally invasive treatment option offering significant long-term improvement in PAP.