Otosclerosis occurs when a series of small bones (shown in brown above) in the Middle Ear grow abnormally. Click on the image above to enlarge.

Otosclerosis is when abnormal growth occurs in a series of bones located the Middle Ear that physically pass on the sensation of sound to the Inner Ear. If the abnormal bone growth is severe enough, it can cause a type of Conductive Hearing Loss. If the abnormal bone growth extends into the Inner Ear, it can also cause Sensorineural Hearing Loss and affect balance.

The condition usually affects the last bone in the Middle Ear called the Stapes located at the entrance to the Cochlea – the organ that senses sound. With Otosclerosis, the Stapes can ‘stick’ to the Cochlea’s entrance and interfere with the mechanical transfer of sound to the Inner Ear.

It often begins in early to mid-adulthood with women aged between 15 and 30 years more likely to develop the condition. Pregnancy can cause Otosclerosis to progress more rapidly.

Symptoms of Otosclerosis

If left untreated, it can cause the slow onset of a Conductive Hearing Loss, which can become more severe over time. Tinnitus and Vertigo can also be associated with the condition.


Treatment options for Otosclerosis can include wearing a Bone-Conduction Hearing Aid or a Bone Anchored Hearing Device to help manage the associated hearing loss symptoms.

Having ear surgery is another option to remove the hearing loss symptoms associated with the condition.  A common ear surgery procedure for Otosclerosis is a Stapedectomy, which involves removing one of the Middle Ear bones called the Stapes and replacing it with a prosthesis.

The other surgical option is a Stapedotomy where only a segment of the Stapes is removed and a small hole drilled at the bottom and putting a piston-like prosthesis in place.