Low-set ears and pinna abnormalities refer to an abnormal shape or position of the outer ear (pinna or auricle).
Low-set ears; Microtia; "Lop" ear; Pinna abnormalities; Genetic defect - pinna; Congenital defect - pinna
The outer ear or "pinna" forms when the baby is growing in the mother's womb. The growth of this ear part takes place at a time when many other organs are developing (such as the kidneys). Abnormal changes in the shape or position of the pinna may be a sign that the baby also has other related problems.
Common abnormal findings include cysts in the pinna or skin tags.
Many children are born with ears that stick out. Although people may comment on the ear shape, this condition is a variation of normal and is not linked with other disorders.
However, the following problems may be related to medical conditions:
Common conditions that can cause low-set and unusually formed ears include:
Rare conditions that can cause low-set and malformed ears include:
In most cases, a health care provider finds pinna abnormalities during the first well-baby exam. This exam is most often done at the hospital at the time of delivery.
The provider will:
To determine whether the pinna is abnormal, the provider will take measurements with a tape measure. Other parts of the body will also be measured, including the eyes, hands, and feet.
All newborns should have a hearing test. Exams for any changes in mental development may be performed as the child grows. Genetic testing may also be done.
Most of the time, no treatment is needed for pinna abnormalities because they do not affect hearing. However, sometimes cosmetic surgery is recommended.
More severe abnormalities may require surgery for cosmetic reasons as well as for function. Surgery to create and attach a new ear is often done in stages.
Haddad J, Dodhia SN. Congenital malformations of the ear. In: Kliegman RM, St. Geme JW, Blum NJ, Shah SS, Tasker RC, Wilson KM, eds. Nelson Textbook of Pediatrics. 21st ed. Philadelphia, PA: Elsevier; 2020:chap 656.
Madan-Khetarpal S, Arnold G, Ortiz D. Genetic disorders and dysmorphic conditions. In: Zitelli BJ, McIntire SC, Nowalk AJ, Garrison J, eds. Zitelli and Davis' Atlas of Pediatric Physical Diagnosis. 8th ed. Philadelphia, PA: Elsevier; 2023:chap 1.
Mitchell AL. Congenital anomalies. In: Martin RJ, Fanaroff AA, Walsh MC, eds. Fanaroff and Martin's Neonatal-Perinatal Medicine. 11th ed. Philadelphia, PA: Elsevier; 2020:chap 30.
Reviewed By: Neil K. Kaneshiro, MD, MHA, Clinical Professor of Pediatrics, University of Washington School of Medicine, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.