Ear Anatomy

When discussing critical information about anatomical features and fittings for an earpiece or impression, it helps if the hearing healthcare professional and the lab share common terminology. Below you will find definitions for the most commonly used terms describing the anatomical features of the ear, as well as illustrations showing those features highlighted on an earpiece. You may find these illustrations and definitions useful when communicating with Westone about the design of your patient’s earpiece.

Westone Ear Anatomy Illustration

The anatomical landmarks described here are of primary importance to the hearing healthcare provider. Several of these hold special significance for the creation of a proper fitting earpiece.

A ridge of cartilage that is part of the pinna, just above the crus that the earpiece fits under

A ridge of cartilage opposite and slightly below the tragus

The opening of the ear canal

Auricle or pinna
The external ear

The bowl-shaped cavity just outside of the opening of the ear canal

Crus (ear) valley (earpiece)
The horizontal piece of cartilage located outside the ear canal that divides the upper and lower parts of the ear

Ear canal
The 2 to 3 cm long external auditory meatus, consisting of an outer cartilaginous portion and an inner bony portion

The intertragal notch located at the bottom of the concha bowl

Helix lock (curl)
A recessed “crevice” at the upper part of the ear, just above the valley

Helix Extension (not including lock)
An extension up to but not including the Helix lock

A small ridge in front of the external opening of the ear canal

Canal length according to Westone
Since each earpiece is as unique as the patient’s ear, discussion of canal length can be a bit confusing. At Westone, we use the anatomical features of each individual ear to describe canal length. Short canals are defined by the center of the first bend of the ear canal, while long canals are centered at the second bend. Using this as the basis for canal length, a medium canal would be cut halfway between the 1st bend and the 2nd bend of the ear, while a medium long canal would be cut halfway between a medium and long canal.