Abstract 13: Timing of Microsurgical Reconstruction in Lower Extremity Trauma

PURPOSE: Marko Godina in his landmark paper in 1986 established the principle of early flap coverage for reconstruction of traumatic lower extremity injuries to minimize edema, fibrosis and infection while optimizing outcomes. However, with the evolution of microsurgery and wound management, recent studies have suggested that reconstruction can be performed beyond this window of 3 days with comparable outcomes. The aim of this study was to determine how timing influences perioperative outcomes in free flap reconstruction for lower extremity trauma. METHODS: A retrospective review of our institutional flap registry from 1979–2016 identified 806 lower extremity free flaps. 358 soft tissue free flaps for below knee trauma performed within one year of injury met inclusion criteria. Patients were stratified based on timing of coverage: ≤3 days (early), 4–90 days (delayed) and >90 days (late). A receiver operating curve (ROC) was generated and Youden index was used to determine the optimal time of reconstruction for predicting flap success. Based on this, the delayed group was further divided into two groups: 4–9 days and 10–90 days. Demographics, flap characteristics and outcomes were compared using Chi-square and one-way ANOVA. Multivariate logistic regression was performed to determine whether timing of reconstruction independently predicts complications and flap failures, controlling for injury-related and operative factors. RESULTS: The mean age was 38.8 years (range 18–83) and 76% of patients were male. 77 free flaps (21.5%) were performed ≤3 days after initial injury, 233 (65.1%) were performed within 4–90 days and 48 (13.4%) flaps were performed after 90 days. There was significant difference in the presence of arterial injury between the groups (64.2% early vs. 46.6% delayed vs. 67.6% late; p=0.014) and timing within cohort. Univariate analysis demonstrated no association between time to coverage and rates of partial flap failure (p=0.11), total flap failure (p=0.44), takebacks (p=0.79) or major complications (p=0.14). Multivariate logistic regression analysis demonstrated that flaps performed within 3 days after injury had decreased risk of major complications (OR 0.40, p=0.04), trend towards decreased risk of partial flap failures (OR 0.13, p=0.06) and any flap failures (OR 0.41, p=0.10) compared to flaps performed between 4–90 days. Our ROC curve demonstrated day 10 to be the optimal day for predicting flap success (AUC=0.56). Multivariate logistic regression analysis demonstrated that flaps performed ≤3 days vs. 4–9 days had no differences in major complications (p=0.08), partial flap failure (p=0.92) or total flap failure (p=0.35). In contrast, flaps performed 10–90 days from injury compared to ≤3 days had increased risk of major complications (OR 2.67, p=0.002) and total flap failure (OR 3.40, p=0.03). CONCLUSION: Early free flap reconstruction performed within 3 days of injury had superior outcomes compared to the delayed (4–90 day) group, consistent with Godina’s original findings. However, as an update to his paradigm, this ideal early period of reconstruction can be safely extended to within 10 days of injury without an adverse effect on outcomes.