Procerus

Origin, Insertion, Action & Nerve

Attachments explained

The Procerus is defined first by where it attaches. Its origin is the more fixed anchor, usually the proximal or more stable end that stays put during contraction, while its insertion is the more mobile point that is pulled toward the origin when the muscle shortens.

Action & function

When the Procerus contracts, it produces the following movement: Draws down the medial angle of the eyebrows, producing transverse wrinkles over the bridge of the nose.

As part of the Facial Expression group of the Head & Neck, it works alongside neighbouring muscles to generate smooth, coordinated movement and to stabilise the structures it acts on.

Nerve supply & clinical relevance

The Procerus receives its nerve supply from the Temporal and zygomatic branches of facial nerve (CN VII).

Because a muscle can only contract when its nerve is intact, injury to the Temporal and zygomatic branches of facial nerve can weaken or paralyse the Procerus, impairing the movements it normally produces (draws down the medial angle of the eyebrows, producing transverse wrinkles over the bridge of the nose). This is why knowing the innervation is central to localising nerve lesions in clinical practice.

How to study the Procerus (the OIANS method)

OIANS stands for Origin, Insertion, Action and Nerve, the four facts that uniquely define every skeletal muscle. To learn the Procerus, work through them in order: picture its origin, trace the muscle to its insertion, reason out the action that shortening between those two points must create, then add the nerve that drives it.

Most students remember the Procerus fastest by linking its action back to its attachments rather than memorising each fact in isolation. Once the origin and insertion make sense, the action usually follows logically.

Procerus quick facts

Region

Head & Neck

Group

Facial Expression

Origin

Fascia over the lower nasal bone and upper lateral nasal cartilage

Insertion

Skin of the lower forehead between the eyebrows (glabella)

Action

Draws down the medial angle of the eyebrows, producing transverse wrinkles over the bridge of the nose

Nerve

Temporal and zygomatic branches of facial nerve (CN VII)

Spinal roots

—

Frequently asked questions

Related muscles