Stapes ankylosis refers to congenital or acquired fixation of the stapes (the stirrup-shaped small bone or ossicle in the middle ear), which is associated with conductive hearing resulting from impairment of the sound-conduction mechanism (the external auditory canal, tympanic membrane, and/or middle-ear ossicles). [https://orcid.org/0000-0002-0736-9199, PMID:12089654]