Anatomical Structure and Location of the Nasalis Muscle

Description

Positioned over the lateral wall of the nose, the nasalis muscle is shown as a superficial band spanning the maxilla and the nasal cartilages, with its fibers arranged around the bony piriform aperture. The transverse part courses medially across the dorsum nasi, lying anterior to the nasal bones and superior to the alar cartilages, while the alar part tracks inferomedially toward the nostril margin on the anterior maxilla. Deep to the muscle, the illustration logically includes the nasal septal cartilage and adjacent lateral nasal cartilage, framed superiorly by the nasal bone and inferiorly by the maxilla and the anterior nasal spine. The mandible, dentition, and upper cervical vertebrae provide craniofacial orientation. Clean landmarks. Functionally, this lateral skull-based presentation clarifies how the nasalis can either compress the nasal aperture (transverse part) or assist in dilating the nares (alar part), depending on the balance with surrounding muscles such as levator labii superioris alaeque nasi. That distinction matters in rhinoplasty planning and in post-traumatic nasal obstruction, where scarring or cartilage graft placement can alter external nasal valve mechanics at the level of the alar rim. It also supports teaching facial nerve motor anatomy, since nasalis receives buccal branch innervation and can be affected in facial palsy with measurable changes in nostril flare and nasal airflow. Educators can drop this artwork into head and neck anatomy lectures on muscles of facial expression, or into ENT and plastic surgery teaching materials covering external nasal valve function, alar base surgery, and common deformity patterns after nasal fracture. It also fits clinical patient education on why nasal breathing may change after septoplasty or cosmetic nasal surgery when soft tissue dynamics, not just the septum, drive symptoms. Anatomical accuracy verified by SciePro's Medical Advisory Board.