Risk factors associated with postoperative necrosis after digital replantation: a systematic review and meta-analysis

Background: Systematically evaluate and quantitatively analyze risk factors associated with necrosis following replantation surgery for amputated fingers, providing evidence-based support for perioperative risk assessment and clinical decision-making. Methods: Systematically searched PubMed, Embase, Web of Science, Cochrane Library, and CNKI, Wan fang, VIP for all observational studies from indexing to January 1, 2026. Cohort studies reporting overall postoperative necrosis after finger replantation, as defined in the original studies, and its associated factors were included. The Newcastle-Ottawa Scale (NOS) was used to assess the methodological quality of included studies. Pooled effect sizes were extracted, and pooled odds ratios (ORs) with 95% confidence intervals (95% CI) were calculated using a random-effects model. Results: A total of 12 studies involving 3,645 patients were included. Meta-analysis results suggest smoking [OR = 3.48, 95% CI (1.96, 6.17)], preoperative ischemic time ≥8 h [OR = 2.25, 95% CI (1.43, 3.54)], crush injury [OR = 2.77, 95% CI (1.41, 5.43)], thrombosis [OR = 4.98, 95% CI (1.49, 16.67)], vein graft [OR = 1.56, 95% CI (1.19, 2.04)] may be associated with necrosis after digital replantation. Conclusion: This study suggests that smoking, preoperative ischemia duration ≥8 h, crush injury, thrombosis, and venous grafting may be associated with an increased risk of overall postoperative necrosis following finger replantation. These findings should be interpreted with caution because outcome definitions were not fully consistent across studies. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/view/CRD420261290184.