The Importance of Variant Anterior Digastric Musculature in Head and Neck Surgery

Abstract

Anterior belly of the digastric muscle (ABDM) variations have been reported to occur in as few as 2.7% to as many as 69.6% of individuals. ABDM variants may cause confusion during surgeries including submental lipectomy, rhytidectomy, surgical alteration of the cervicomental angle via partial resection of the ABDM, muscle transfer for reanimation of the mouth, and submental artery flap procedures. Therefore, knowledge of ABMD variants may aid in surgical planning and prevent confusion and disorientation during operations in the submental region. This report presents examples of ABMD variants and promotes novel ideas for the utilization of variant ABDM transfer to reanimate the mouth after marginal mandibular branch of facial nerve (MMBFN) palsy. Also presented is a unique perspective with regard to exclusion of normal and variant ABDM from the submental artery flap as a surgical contingency plan in the event of MMBFN palsy occurring as a result of flap surgery. Research was supported by funding from the WV Research Challenge Fund [HEPC.dsr.14.13].