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The corrugator supercilii muscle revisited.

BACKGROUND
Few studies have examined the anatomy of the central forehead as it pertains to vertical glabellar furrows.


OBJECTIVE
This study sought to critically examine the corrugator supercilii muscle (CSM) in situ, in relation to surrounding bony and soft tissue landmarks.


METHODS
Anatomic dissection of 10 fresh cadaveric hemi-heads was performed, focusing on the CSM origin and insertion, with emphasis on regional fascial relations, neurovascular structures, and osseous topography.


RESULTS
The CSM originates along the supraciliary arch. The muscle is attached at its medial and superior margin, whereas the lateral and inferior margins are free. The muscle originates from a bony plateau on the supraciliary arch. The CSM travels laterally, with most of the muscle passing through the fibers of the orbicularis oculi and the frontalis. The dermal insertion of the muscle is under the central portion of the eyebrow. The nerve supply enters at the lateral aspect of the muscle approximately 5 mm cephalic to the lateral brow. The action of the CSM is to elevate the medial aspect of the brow and depress the lateral segment of the brow.


CONCLUSION
The CSM does not appear to be the primary determinant of vertical glabellar frown lines. (Aesthetic Surg J 2001;21:209-215.).