EPITYMPANIC fixation of the incus, the malleus, or both can occur without prior chronic otitis media. Such fixation is more frequent in ears with otosclerotic ankylosis of the stapes than in the general population. It may occur following trauma to the ossicular chain, or without apparent precipitating cause. The fundamental cause seems to be a failure of development of the epitympanic space leaving the ossicles in close contact with the epitympanic walls. Fixation is then more prone to occur.
It is the purpose of this paper to report a total of 53 ears in 52 patients with fixation of the incus, malleus, or both.
In 16 patients there was evidence of infectious middle ear disease, but in 36 patients there was no historical, clinical, or histologic evidence of prior acute or chronic otitis media. The mechanism of ossicular fixation in chronic otitis media, with or without tympanosclerosis, is well documented,