Congenital absence of stapedius muscle and tendon: Rare finding in two cases

Abstract

During surgery for otosclerosis, the surgeon cut the stapedius tendon before removing stapes suprastructure. The absence of the stapedius tendon is uncommon. In this case report, we present two cases of the absence of the unilateral stapedius tendon with muscle. During exploratory tympanotomy of the right ear in the first patient and left ear in the second patient with moderately severe mixed hearing loss, the absence of the stapedius tendon was found. The tympanic cavity was explored with the help of a Zeiss microscope by endomeatal route. The pyramidal process and stapedius muscle with its tendon were absent. Awareness of the variations or anomalies of the stapedius muscle and tendon is important for surgeons who operate upon the tympanic cavity, especially during surgery for ossicular fixation or ossicular discontinuity. As most of the time, these anomalies may be associated with the other middle ear anomalies.