Lower extremity amputation: the emerging role of targeted muscle reinnervation (TMR) and regenerative peripheral nerve interface (RPNI)

Lower extremity amputation is increasingly prevalent in the United States, with growing numbers of patients suffering from diabetes and peripheral vascular disease. Amputation has significant functional sequelae as more than half of patients are unable to ambulate at one year postoperatively. Improving mobility and decreasing chronic post-amputation pain can significantly improve the quality of life for these patients and reduce the cost burden on the healthcare system. Plastic and reconstructive surgery has been at the forefront of "reconstructive amputation", in which nerve pedicles can be surgically guided to decrease painful neuroma formation as well as provide targets for myoelectric prosthesis use. We herein review post-amputation outcomes, epidemiology of chronic, postamputation pain, and current treatments, including total muscle reinnervation and regenerative peripheral nerve interface, which are at the forefront of multidisciplinary treatment of lower extremity amputees.