Surgical complications after targeted muscle reinnervation at a safety-net hospital

BACKGROUND Targeted muscle reinnervation (TMR) and regenerative peripheral nerve interface (RPNI) can reduce rates of neuroma formation and phantom limb pain (PLP) after lower extremity (LE) amputation. However, these techniques have not been examined for patients at safety-net hospitals. The purpose of this study is to examine surgical complication rates after TMR and/or RPNI at a safety-net hospital. METHODS This was a retrospective review of patients >18 years who had prior above- (AKA) or below-knee (BKA) guillotine amputation and underwent stump formalization with TMR and/or RPNI from 2020 to 2022. Demographics, medical history, operative and postoperative characteristics were collected. The primary outcome was any surgical complication, defined as infection, dehiscence, hematoma, neuroma, or reoperation. Univariate analysis was conducted to identify variables associated with surgical complications and PLP. RESULTS Thirty-two patients met inclusion criteria. The median age was 52 years, and 75% were male. BKA was the most common indication for formalization (93.8%). Most patients (56.3%) had formalization with TMR and RPNI, 34.4% patients had TMR only, and 9.4% had RPNI alone. The incidence of postoperative complications was 46.9%, with infection being the most common (31.3%). There was no significant difference in demographics, medical history, or operative characteristics between patients who did and did not have surgical complications. However, there was a trend toward higher rates of PLP in patients who had a postoperative wound infection (odds ratio 6.2, 95% CI 0.70-84.6, p = 0.06). CONCLUSION Overall complication rates after LE formalization with TMR and/or RPNI at our safety-net hospital were similar to what has been reported in the literature. Given the benefits of these surgical techniques, including reduced chronic pain and decreased healthcare cost, we believe that these techniques should be widely adopted at other safety-net hospitals.