procerus

Procerus is a small facial muscle of expression, located on the lower part of the forehead between the eyebrows. It lies over the nasal bones and medial aspects of the nasal bridge and blends with adjacent muscles of the brow region.

Anatomy and attachments

The procerus arises from the fascia over the lower nasal bone and the upper part of the lateral nasal cartilages. Its fibers ascend and medially insert into the skin of the lower forehead between the eyebrows, frequently blending with the medial fibers of the frontalis and the corrugator supercilii. The muscle is typically described as lying superficial to the nasal bones and nasal dorsum.

Function

The primary action of the procerus is to depress the medial portion of the eyebrows and draw the skin of the glabella downward, producing transverse wrinkles over the bridge of the nose. It works in concert with the corrugator supercilii to create frown expressions and to modulate facial expressions related to concentration or displeasure.

Innervation and blood supply

The procerus is innervated by branches of the facial nerve (cranial nerve VII). Its arterial supply comes from perforating branches of the facial artery and adjacent vessels in the brow region.

Clinical relevance

In cosmetic and reconstructive practice, the procerus can be targeted with botulinum toxin to reduce glabellar or nasal bridge lines. Dysfunction or hypertrophy is rare, but alterations in its activity can influence the appearance of frown lines and the overall dynamics of brow movement.

See also

Corrugator supercilii, frontalis muscle, glabella.