Predicting limb amputation in trauma-related necrotizing fasciitis of the extremities: insights from a 10-year cohort

BACKGROUND: Necrotizing fasciitis (NF) is a rapidly progressive, life-threatening soft tissue infection that in most cases requires aggressive surgical management. Major limb amputation is a devastating limb-related outcome. We retrospectively analyzed NF cases to quantify the rate of amputation and identify associated risk factors. METHODS: We retrospectively reviewed the medical records of all patients with trauma-related extremity NF treated at Hebei Medical University Third Hospital from Jan 2014 to Dec 2024. Demographics, comorbidities, admission laboratories and key time intervals were compared between patients who did and did not undergo major limb amputation. Multivariable logistic regression identified independent predictors, and receiver operating characteristic (ROC) analysis assessed the discriminative power of continuous variables. RESULTS: Of 134 patients, 22 (16.4%) required amputation. Compared with the non-amputation group, amputees had a markedly longer pre-hospital delay (median 242 h vs. 65 h), more multiple injuries (63.6% vs. 13.4%) and a higher prevalence of diabetes (59.1% vs. 21.4%). Admission lactate dehydrogenase (LDH) was substantially higher (median 589 vs. 182 U/L). In multivariable analysis, elevated LDH, prolonged time from traumatic injury to hospital admission, multiple injuries and diabetes were independently associated with amputation. LDH displayed excellent discrimination for amputation (AUC = 0.91), while pre-hospital delay showed good accuracy (AUC = 0.84). CONCLUSIONS: Roughly one in six patients with trauma-related extremity NF required limb amputation in this single-center cohort. High LDH on admission, delayed presentation, multiple injury sites and diabetes reliably identify the patients at greatest risk. Prompt recognition and aggressive management of these high-risk individuals are crucial for improving limb-salvage outcomes. CLINICAL TRIAL NUMBER: Not applicable.