Exostosis, sometimes referred to as surfer’s ear, occurs when there is abnormal bone growth within the ear canal. This thickening and constriction of the ear canal can lead to conduction hearing loss. Ear wax and other debris can become trapped in the canal, which can cause frequent ear infections. The most common cause of exostosis is cold water and windy conditions, which makes exostosis especially prevalent among surfers, outdoor swimmers, and divers.
Exostoses frequently occur in both ears; however, they can grow at different rates. These growths do not resolve on their own; however, it often takes years before they are large enough to cause symptoms and require treatment.
Exostosis present as small bony lumps within the external ear canal. These lumps are very slow growing and typically take years to develop. They develop as thin layers of bone growth due to the stimulation of cold water or air.