Pinna abnormalities and low-set ears refer to abnormalities in the shape or position of the outer ear (pinna or auricle).

During fetal development, the outer ear or "pinna" forms at a time when many other critical organs are developing (such as the kidneys). Abnormalities in the shape or positioning of the pinna may be an indication that there are other associated abnormalities present.

Common abnormalities include abnormal folds in the pinna, prominence of the ears, low-set positioning, abnormal rotation of the pinna, and even absence of the pinna.

Many children are born with ears that stick out (protruding ears). Although people may comment on the ear shape, this condition is a variation of normal and is not associated with other disorders. However, low-set ears, absent pinna, and abnormal folds may be associated with various medical conditions.

The following common conditions are associated with low-set and malformed ears:

• Down syndrome
• Turner syndrome

Rare conditions associated with low-set and malformed ears include:

• Treacher Collins syndrome
• Potter syndrome
• Trisomy 18
• Beckwith-Wiedemann syndrome
• Trisomy 13
• Rubinstein-Taybi syndrome
• Smith-Lemli-Opitz syndrome

Call if you notice abnormally shaped or positioned ears.

In most cases, pinna abnormalities are found by a health care provider during the first well baby exam. This exam is usually performed at the hospital, if that is where the baby is delivered.

The doctor will ask medical history questions, such as:

• Are you aware of any other physical abnormalities?
• Is there any family history of having abnormal-shaped ears?
• Is there a family history of any of the disorders associated with pinna abnormalities and low set ears?

To determine if the pinna is abnormal, the doctor will conduct a series of measurements with a tape measure. Other parts of the body will be measured, including the eyes, hands, and feet, to determine if other abnormalities are present.

All newborns should have a hearing test. A child with pinna abnormalities should certainly have a hearing test, if he or she hasn't already. Examination for any mental development changes may be performed as the child grows. Diagnostic tests that may be performed include a chromosome analysis.

No treatment is needed for pinna abnormalities, as they do not affect the hearing. However, sometimes cosmetic surgery is recommended.