Expanding the Criteria for Targeted Muscle Reinnervation: A National Assessment of Eligibility

Abstract PURPOSE This study represents an effort to examine the national eligibility of patients who would benefit from lower extremity (LE) targeted muscle reinnervation (TMR) in the United States. The objective of this study is to quantify and characterize the patient population eligible for LE TMR. METHODS Using the National Inpatient Sample database from 2008 to 2015, patients undergoing lower extremity amputations were identified by ICD-9 diagnosis code. Differences in patient-level demographic parameters and hospital-level factors were compared using descriptive statistics. RESULTS Over the study period, a weighted total of 369,717 patients met inclusion criteria, representing an annual mean of 46,214 patients per year. 214,756 patients underwent below-knee amputation, and 150,634 underwent above-knee amputation. Patients were predominantly male (63%), from the south (47.4%), and of the lowest income quartile (38.8%). Younger patients were more likely to be privately insured (44.1%) or on Medicaid (44.1%), while older patients were predominantly on Medicare (89.4%). Peripheral vascular disease affected 45.5%, 51.3%, and 52.0% of patients in the sixth, seventh, and eighth decades of life respectively. Black patients also made up 26% of amputations despite only composing 13% of the overall population. CONCLUSIONS At least 46,214 patients per year present a population that would possibly benefit from TMR, with about half of those with peripheral vascular disease. In addition to the high prevalence of vascular disease, low-income, minority individuals are disproportionately affected by LE amputation.