Design of skin islands for a myocutaneous serratus anterior free flap—An anatomical study and clinical implication for pharyngeal reconstruction after laryngopharyngectomy

Objectives: The main purpose of this study was to evaluate flap size and flap design of skin islands in myocutaneous serratus anterior free flaps (SAFFs) in fresh cadavers and to further investigate whether myocutaneous SAFFs are suitable flaps for pharyngeal reconstruction after laryngopharyngectomy. Methods: Dissection and injection of methylene blue were performed in 20 hemithoraces of 13 fresh cadavers to evaluate flap size and location of skin islands. Based on these pre-clinical data, we performed pharyngeal reconstruction with myocutaneous SAFF in five patients after laryngopharyngectomy. Results: Perfused skin paddles were found in all specimens with a mean size of perfused skin islands of 85.6 ± 49.8 cm ² . Lengths and widths of skin islands ranged from 10-21 cm and 6-20.5 cm respectively. Flap size did not significantly differ between males and females (P = 0.998), left compared to right hemithoraces (P = 0.468) and between paired specimens (P = 0.915). All skin islands were found within the upper 29.3%-51.7% of hemithorax (calculated from axilla to costal arch), and between latissimus dorsi muscle posteriorly and anterior axillary line anteriorly. Accordingly, myocutaneous SAFFs were used for pharyngeal reconstruction after laryngopharyngectomy in five patients with advanced hypopharyngeal carcinomas. Three patients had uneventful courses, while one patient developed immediate intraoperative flap loss and another patient developed partial necrosis of SAFF on postoperative day 7. Conclusion: Skin islands of SAFF have reliable blood supply, which allow harvest of large myocutaneous SAFFs that can be used also for pharyngeal reconstruction after laryngopharyngectomy.