(A526) Comparative Analysis of Osteocutaneous Free Flaps and Patient Factors in Mandibular and Maxillary Reconstruction Outcomes

Introduction: Defects of the maxilla and mandible resulting from malignancy, trauma, or osteoradionecrosis require complex surgical intervention. This study examines the use of osteocutaneous free flaps and patient factors affecting postoperative outcomes.

Methods: Retrospective chart review of patients undergoing flap repair of mandibular and maxillary defects at Atrium Health Wake Forest Baptist Hospital (2010–2020). Independent variables: flap type, cancer type, defect size, defect type, bone graft size, skin paddle size, smoking status, and preoperative radiation. Primary outcomes: postoperative infection, venous congestion, flap necrosis, fistula, dehiscence, arterial thrombosis, and flap revision within 30 days.

Results: Patients: 177. Gender: 103/177 (58%) male, 74/177 (42%) female. Flap type: scapula 83/177 (47%), parascapula 67/177 (38%), fibula 27/177 (15%). Venous congestion was associated with defect type (p=0.017); maxilla defects showed the lowest rates, and combined maxilla-mandible defects had the highest rates. Flap type was significantly associated with necrosis (p=0.034) and infection (p=0.038). Fibula flaps had the highest postoperative necrosis and infection rates, while scapula flaps had the lowest necrosis and dehiscence rates (OR 0.25, 95% CI: 0.07-0.78, p=0.019; OR 0.31, 95% CI: 0.09-0.98, p=0.048). Smokers had a 3.32-fold higher risk of postoperative dehiscence than non-smokers (OR 3.32, 95% CI: 1.17-10.2, p=0.028). No significant associations were found between cancer type, defect size, graft size, paddle size, or radiation and any complication. Flap type was not associated with postoperative flap revision within 30 days (p=0.064).

Conclusions: Combined maxillary and mandibular defects demonstrated the highest postoperative complication rates. Scapula flaps reconstructed multiple defect types with the lowest complication rates. Fibula flaps, associated with high necrosis and infection rates, may be better suited for select defects. Smoking significantly increased reconstruction complications.