Ossicles

Ossicles (malleus, incus and stapes) are bones which conduct sound from the tympanic membrane.

The handle and lateral process of the malleus is attached to the tympanic membrane and can be easily seen on the physical exam. The long process of the incus can often be seen through the posterior superior quadrant of the membrane. The stapes is attached to a foot plate which is in direct contact with the fluid of the inner ear.2

Inadvertently touching the ossicles with the drill will cause a large vibration, which will then be transmitted into the inner ear. That is likely to cause a significant permanent hearing loss.

2 Gray’s anatomy online, www.education.yahoo.com/reference/gray