Auricularis Posterior

Ear · Head & Neck

Located in the Ear of the Head & Neck, the Auricularis Posterior is a key muscle for anatomy study. Originating at Mastoid part of the temporal bone (via a short aponeurosis), it inserts at Ponticulus on the cranial surface of the concha. Functionally, it draws the auricle backward. Its nerve supply is the Posterior auricular branch of facial nerve (CN VII).

Origin, Insertion, Action & Nerve

Origin

Mastoid part of the temporal bone (via a short aponeurosis)

Insertion

Ponticulus on the cranial surface of the concha

Action

Draws the auricle backward

Nerve

Posterior auricular branch of facial nerve (CN VII)

Attachments explained

The Auricularis Posterior 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.

Origin

Mastoid part of the temporal bone (via a short aponeurosis)

Insertion

Ponticulus on the cranial surface of the concha

Action & function

When the Auricularis Posterior contracts, it produces the following movement: Draws the auricle backward.

As part of the Ear 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 Auricularis Posterior receives its nerve supply from the Posterior auricular branch of facial nerve (CN VII).

Because a muscle can only contract when its nerve is intact, injury to the Posterior auricular branch of facial nerve can weaken or paralyse the Auricularis Posterior, impairing the movements it normally produces (draws the auricle backward). This is why knowing the innervation is central to localising nerve lesions in clinical practice.

How to study the Auricularis Posterior (the OIANS method)

OIANS stands for Origin, Insertion, Action and Nerve, the four facts that uniquely define every skeletal muscle. To learn the Auricularis Posterior, 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 Auricularis Posterior 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.