Last updated: 11/24/2009

Statistics for congenital deformities of the external ear are difficult to obtain because the causes are so diverse. Such genetic disorders as Treacher Collins syndrome and hemifacial microsomia affect between one in 3,500 and one in 10,000 children....

In addition, microtia has been associated with certain medications taken during pregnancy—particularly anticonvulsants, which are drugs given to treat epilepsy, and isotretinoin, a drug prescribed for severe acne.

Stahl's deformity is found more often among Asian Americans than among Caucasian or African Americans. As of 2003, it is thought to be a hereditary disorder.

Setback or pinback otoplasty is the most frequently performed procedure for reconstruction of prominent or protruding ears. According to the American Society of Plastic Surgeons, 33,107 setback otoplasties were performed in the United States in 2001. This figure represents about 2% of all plastic surgical procedures. There are no exact statistics on the incidence of protruding ears in the general population, although about 8% of patients treated for this deformity have a family history of it. Large or protruding ears appear to be equally common in males and females; however, it is easier for girls and women to avoid social discomfort by styling their hair to cover their ears. This factor may explain why a slight majority (53%) of setback otoplasties is done on boys. Although most setback otoplasties are performed in children between the ages of four and 14, the second largest group of patients in this category is women in their 20s and 30s.

The most common cause of trauma requiring otoplasty is human and animal bites. Although exact figures are not known because many bite cases are not reported, a large percentage of dog and human bites cause wounds on the head and neck. With regard to human bites, the single most common injury requiring medical treatment is auricular avulsion, or tearing of the external ear. In the United States, 93% of patients treated for ear injuries caused by human bites are males between the ages of 15 and 25. Most cases of auricular avulsion in children, however, are caused by dog bites, which are likely to cause crushing as well as tearing of the tissues. Although statistics cover bites on all parts of the body, it is still noteworthy that plastic surgeons in the United States performed 43,687 operations to repair injuries caused by animal bites in 2001.