Familial Occurrence of Congenital Stapes Footplate Fixation

Abstract Congenital stapes footplate fixation is not so common in the clinical otology. The clinical features are the fixation of the stapedial footplate, and the consequent conductive hearing loss with flat curve at the level of 50 to 60 dB in air conduction since birth. Its familial occurrence have never been reported before. The authors found five these cases in one family. All five cases were females, two of whom were sisters and other three were cousins. Their mothers had not particular disturbances in the early stage of pregnancy. The sex‐linked heredity was highly suspected in this familial occurrence. All the cases showed bilateral conductive hearing loss. Tympanotomies on all cases revealed no abnormality of the middle ear cavity, except that all the stapes were not mobile at the footplate in spite of the normal shape. Openings of a small fenestra onto the footplate were performed and teflon piston wire prostheses were used to reconstruct the new conducting route. The excellent improvement of postoperative hearing was gained in all the cases. Furthermore, out of family members another three cases with hearing loss were found. Pathogenesis was discussed in consideration of the developmental process of the stapes and histopathological findings in the previous reports.