Which is the most common cause of conductive hearing loss due to bone growth immobilizing the stapes?

Which is the most common cause of conductive hearing loss due to bone growth immobilizing the stapes?

• A. Otosclerosis
• B. Epistaxis
• C. Olfactory organ
• D. Otitis externa

Answer: (A)

Stapes immobilization from abnormal bone growth in the middle ear is otosclerosis. In this condition, bone around the stapes footplate becomes sclerotic and fixed, so the stapes can’t move properly in response to sound. That stops the efficient transmission of vibrations from the eardrum through the ossicular chain to the inner ear, producing conductive hearing loss. It’s the most common cause of this type of loss because the fixation directly disrupts how sound is conveyed through the middle ear. It often runs in families and commonly affects young to middle-aged adults. On an audiogram, a Carhart notch around 2000 Hz may appear due to the stapes being less mobile. Treatments like stapedectomy or stapedotomy aim to restore movement of the stapes and improve hearing. The other options don’t fit because they involve the external ear or nasal regions rather than fixation of the stapes: a nosebleed, the smell organ, or an outer ear infection don’t cause conductive hearing loss through bone growth immobilizing the stapes.

Stapes immobilization from abnormal bone growth in the middle ear is otosclerosis. In this condition, bone around the stapes footplate becomes sclerotic and fixed, so the stapes can’t move properly in response to sound. That stops the efficient transmission of vibrations from the eardrum through the ossicular chain to the inner ear, producing conductive hearing loss. It’s the most common cause of this type of loss because the fixation directly disrupts how sound is conveyed through the middle ear. It often runs in families and commonly affects young to middle-aged adults. On an audiogram, a Carhart notch around 2000 Hz may appear due to the stapes being less mobile. Treatments like stapedectomy or stapedotomy aim to restore movement of the stapes and improve hearing.

The other options don’t fit because they involve the external ear or nasal regions rather than fixation of the stapes: a nosebleed, the smell organ, or an outer ear infection don’t cause conductive hearing loss through bone growth immobilizing the stapes.