(627) Impact of Flexor Hallucis Longus Resuspension on Donor-Site Outcomes After Fibula Free Flap Reconstruction

Introduction: Flexor hallucis longus (FHL) detachment during fibula free flap (FFF) harvest may contribute to donor-site morbidity; however, the long-term effect of FHL resuspension remains unclear.

Methods: An institutionally approved cross-sectional survey study was conducted at a single academic center, including adults who underwent FFF reconstruction for head and neck defects (2020–2025) and were at least six months postoperative. Patients were grouped by surgical technique (FHL resuspension vs no resuspension). The primary objective was to evaluate whether resuspension is associated with improved patient-reported outcomes as measured by the Foot and Ankle Outcome Score (FAOS), with lower scores indicating worse function. The difference in FAOS scores between cohorts represents the effect size with 95% confidence intervals. Demographic and surgical variables were compared with univariable Fisher’s exact test and Student’s t-test, as appropriate. Significance was set at p< 0.05.

Results: Ten patients completed surveys at a median of 38.7 months (range 20–65) after surgery; three underwent FHL resuspension and seven did not. Baseline characteristics did not differ between groups (all p>0.185). Patients who underwent resuspension demonstrated higher total FAOS scores (mean difference 14.4 [-30.6–59.5]; p=0.481), with similar trends across all subscales including symptoms, pain, daily function, recreational function, and QOL. No between-group differences were observed in lower extremity sensation, physical therapy utilization, or gait-assistive device use.

Conclusions: These preliminary findings are promising, and data collection is ongoing to determine whether FHL resuspension confers improved functional outcomes following FFF reconstruction.