Incidence of Congenital Stapes Footplate Fixation Since 1970: A Population-based Study.

OBJECTIVE

Several reports have suggested that the incidence of otosclerosis is declining. However, due to the limitations of epidemiologic databases within the United States, little is known about the incidence of congenital stapes footplate fixation (CSFF), much less epidemiological trends over the past 50 years. The current study was conceived to characterize the epidemiology of CSFF over the past five decades using the unique resources of the Rochester Epidemiology Project (REP).

STUDY DESIGN

Population-based study.

PATIENTS

The medical records of every resident of Olmsted County, Minnesota who was diagnosed with CSFF was reviewed from January 1, 1970 to December 12, 2017 using the REP. The population of Olmsted County on January 1, 2017 was 159,689 persons.

MAIN OUTCOME MEASURE

Incidence of CSFF.

RESULTS

Sixteen cases of CSFF were identified at a median age at diagnosis of 8 years (IQR, 6-17), eight of whom confirmed by exploratory tympanotomy. Three of the 16 (19%) cases were bilateral, and the median pure-tone average (500, 1k, 2k, 3k Hz) at time of diagnosis was 37 dB (IQR, 31-48). Two (13%) cases were identified in patients bearing a syndromic condition and one (6%) case demonstrated a malformed external ear on physical examination. The incidence rate of surgically confirmed cases among residents of Olmsted County was 0.31 per 100,000 person-years from 1970 to 1979 and 0.28 from 2000 to 2009. No incident cases among residents of Olmsted County were identified since 2010.

CONCLUSIONS

CSFF constitutes a rare disease. Unlike epidemiological trends in otosclerosis, the incidence of surgically confirmed cases of CSFF remained stable over the past 50 years.