Congenital malformation of ear ossicles

This code signifies a birth defect affecting the small bones (malleus, incus, stapes) within the middle ear. These malformations can lead to conductive hearing loss due to impaired sound transmission to the inner ear. The anomaly is present at birth, though it may not be diagnosed until later in life.

Assign this code when documentation specifies a congenital structural abnormality of the ear ossicles, such as ossicular chain discontinuity, fixation, or absence. This is typically supported by imaging studies (e.g., CT scan of the temporal bone) or surgical findings during tympanoplasty or ossiculoplasty.

• Do not use for acquired ossicular damage (e.g., trauma, otosclerosis).
• Always code any associated hearing loss (e.g., H90.x) as a secondary diagnosis.
• Specify laterality (left, right, bilateral) if documented, using the appropriate subcategory.