Ankylosis of ear ossicles, unspecified ear

This code describes the stiffening or fusion of the small bones (malleus, incus, stapes) within the middle ear, without specifying which ear is affected. This ankylosis impedes the normal transmission of sound vibrations from the eardrum to the inner ear, leading to conductive hearing loss.

Use this code when documentation indicates ankylosis of the ear ossicles but does not specify laterality (left or right ear). This diagnosis is often made following audiometric testing demonstrating conductive hearing loss and otoscopic examination or imaging studies revealing ossicular fixation.

• Do not use this code if the laterality of the ankylosis is documented; instead, select the appropriate code for the left (H74.312) or right (H74.311) ear.
• Consider codes for associated conductive hearing loss (e.g., H90.0x) if documented.
• Ensure documentation clearly supports ossicular ankylosis, differentiating it from other causes of conductive hearing loss.