Morphological and anthropometrical features of human ear ossicles: A 1-year cadaveric observational study

Abstract

Introduction: The ossicular chain formed by malleus, incus, and stapes, is considered an essential content of the middle ear and is responsible for the transmission of sound vibrations from the tympanic membrane to the oval window. This study aims to evaluate the morphology and anthropometry of ossicles from human cadavers. Material and Methods: This is a cross-sectional study conducted in the Department of Otorhinolaryngology and Head-and-Neck Surgery of KAHER's JN Medical College, Belagavi, for 1 year. Twenty fresh cadavers (40 sets of ossicles) were dissected using zero-degree endoscope. With gentle manipulation, ossicles were removed to study anthropometry and morphology of each middle ear bone using osseous sizer. Results: Among the three bones, based on mean measurements, the heaviest bone was incus (19.08 mg), followed by malleus (16.65 mg) and the lightest bone was stapes (2.28 mg). The longest bone among the three bones was malleus (7.18 mm), followed by incus (5.71 mm) and stapes (2.70 mm). Malleus showed variations in the distal ends, incus showed variation in the lenticular process and the obturator foramen of stapes had different shapes. Discussion and Conclusion: With a rapid rise in the demand for ossiculoplasty in India, knowledge of morphology and possible anthropometric variation existing in Indian subjects is needed to add up to a better understanding of middle ear dynamics.