Ear Canal Exostosis

Exostosis is the medical term for an abnormal growth of bone within the ear canal. It is more commonly referred to as swimmer’s or surfer’s ear. This common name derives from the fact that the most common cause of exostosis is frequent exposure to cold water, making this a condition that affects surfers at a higher rate than the average population. Exposure to wind and cold water causes the bone surrounding the ear canal to thicken and constrict the ear canal, sometimes to the point of complete blockage (known as “occlusion”) which can lead to substantial conductive hearing loss. An exostosis growth can result from any activity that exposes the participant to cold, wet and windy conditions such as skiing, kayaking, fishing, sailing or diving.

The normal ear canal is 5-8mm in diameter (about as thick as a pencil). As the narrowing of the canal from exostosis progresses, this diameter gets substantially reduced, to the point of total closure if the exostosis remains untreated. Exostosis in not necessarily harmful by itself, but the ear canal construction from the bony growth can trap cerumen (ear wax) and other debris within the ear canal, which may lead to repeated ear infections.

Exostosis symptoms include a decrease in hearing sensitivity possibly combined with an increased prevalence of ear infections. Early symptoms include water trapping in the ear canal after swimming. Sometime thereafter, debris trapping and infections make surgery necessary. Exostosis is most commonly treated by a surgical procedure to remove the growth.