Alar Nasalis Muscle Beneath the Skin, Anterior View

Description

Frontal dissection planes expose the alar part of the nasalis muscle immediately deep to the skin of the nose, wrapping around the margins of the external nasal aperture at the level of the alae. Fibers arise from the maxilla lateral to the piriform (anterior nasal) aperture and sweep medially and superiorly toward the alar cartilage, lying superficial to the lateral nasal cartilages and anterior to the nasal septum. Superiorly the nasal bones and frontal process of the maxilla frame the bony dorsum, while inferiorly the upper dentition and anterior maxilla provide fixed landmarks for the soft tissue envelope. Orientation is straightforward. Functionally, the alar nasalis modulates the external nasal valve by stabilizing and dilating the nostril during inspiration, counterbalancing compressive forces from the transverse part of the nasalis and adjacent perinasal muscles; that interplay matters when evaluating dynamic nasal obstruction and alar collapse. Surgeons planning functional rhinoplasty, alar base reduction, or cleft-related nasal reconstruction often need a clear mental map of where these fibers sit relative to the alar cartilage and the piriform aperture, because small changes in soft tissue tension can narrow the valve. Denervation patterns also matter: weakness after facial nerve injury (buccal and zygomatic branches to the perinasal musculature) can present as asymmetric nostril flare and airflow complaints. Use this asset in head and neck anatomy teaching to correlate surface landmarks with the underlying nasalis, in ENT and facial plastic surgery texts discussing the external nasal valve, and in dental or maxillofacial references that tie the maxilla and piriform aperture to perinasal muscle origins and surgical incisions. Anatomical accuracy verified by SciePro's Medical Advisory Board.