By Mapula Mokwena (Clinical audiologist)

What is Otosclerosis?

Otosclerosis is an abnormal bony growth in the middle ear that causes hearing loss.


People who have otosclerosis have an abnormal extension of sponge-like bone that extends into the middle ear cavity. This growth hinders the bones’ ability to vibrate in response to sound waves. These vibrations are needed in order for us to hear. Otosclerosis is the most common cause of middle ear hearing loss in young adults. It usually starts in early to mid-adulthood. It is more common in women than in men and can affect one or both ears. Pregnancy and a family history of hearing loss are risk factors for this condition.


Symptoms include:

  • Hearing loss (slow at first but worsens over time).
  • Ringing in the affected ear (tinnitus).
  • Vertigo or dizziness.


Otosclerosis may worsen gradually. The condition might not require treatment until more severe hearing loss is experienced. The hearing loss may be treated with a hearing aid, while it might assist with symptoms it will not cure or stop the hearing loss from getting worse. Surgery can improve conductive hearing loss. Either all or part of the small middle ear bones behind the eardrum (stapes) is removed and replaced with a prosthesis. A complete replacement is called a stapedectomy. Occasionally, just a little portion of the stapes is removed.

Sourced from PennMedicine.or