Otosclerosis is a middle ear condition that causes hearing loss in one or both ears. It most commonly affects adults in their late 20s or 30s.
Abnormal bone gradually grows around, and on to, the stapes, one of the tiny bones (ossicles) in your middle ear. This reduces the movement of the stapes.
As a result, the ossicles aren’t able to move and pass sound waves into the inner ear as efficiently as they used to, causing hearing loss. Eventually, the stapes becomes fixed so it can’t move at all – this can cause severe hearing loss.
In most cases, otosclerosis just affects the stapes. But in rare cases, the shell of the cochlea and the hair cells in it are also affected.
Hearing aids are very useful if you have otosclerosis, but they won’t stop your hearing loss from worsening. The doctor may discuss the option of having an operation called a stapedectomy, where a surgeon replaces the stapes with an artificial bone made from metal or plastic, so that sound can travel to the inner ear. This operation has a high success rate.
Find out more in our Otosclerosis factsheet.