Morphological Study of Middle Ear Ossicles in North Indian Population - A Cadaveric Study

Abstract

Aim: To study the morphology of malleus, incus and stapes in North Indian population.

Material and Methods: The ossicles were obtained from tympanic cavity for which we used a chisel, a hammer, fine forceps and hooked needle to extract these three bones. To expose the head of malleus, body and short process of incus, the attic needed to be opened up by meticulously dissecting the part. After obtaining the three sets of bones they were studied under hand lens for gross morphological variations and morphometric measurements were estimated with a Mitutoyo micrometer which has an accuracy of 0.01 mm.

Results: The free ends (distal part) of manibrium mallei showed variations between a curve anteriorly (50%) and a straight line. The incus had minimum morphological variations in the ossicles. There was a notch in the inferior border of the short process (42.2%). Courses of these notches were forward or upward. Stapes had maximum morphological variations in the middle ear ossicle. The variations of stapes were in the neck, the cruses and the hole.

Conclusions: From such analytical study of the ossicles, it could be concluded that the stapes is the most variable and the incus is the most stable ossicle so far as morphological variations are concerned.