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what is the shape of bones in ear like malleus, incus ,stapes,?
The smallest bones in the body are the ear bones or the middle ear ossicles. The 3 auditory ossicles located in the middle ear space, are called the malleus, incus and stapes. They connect with each other to form the ossicular chain that plays a vital role in the transmission of sound for hearing by the ear.

Malleus – The Ear Bone Called Hammer

The malleus is shaped like a hammer with a head and a neck that taper off to form a long and thin handle. While the handle is firmly attached to the ear drum, the head of the malleus connects with the incus, the next ear bone, to form a joint.

When sound waves striking the ear drum set it vibrating, the handle of the malleus attached to it starts to vibrate as well. These vibrations are then transmitted to the incus through the joint.

Incus – The Ear Bone Called Anvil

The incus or anvil has a body, a short process and a thin, long process. While the body connects with the malleus, the long process fits neatly with the head of the stapes to form a joint. The incus serves to transmit vibrations from the malleus to the stapes.

Stapes or Stirrup – The Smallest Bone in the Body

This bone looks exactly like a miniature stirrup. It has a foot plate and an arch of thin bone with a small, button-like head on top. This is the smallest bone in the body, measuring about 3.5 mm in height and weighing about 3-4 mg.

The head of the stapes connects with the long process of the incus. Its footplate fits neatly into the oval window of the middle ear, covering it completely. So the stapes helps pass on vibrations from the incus to the inner ear lying beyond the oval window. The rocking movement of the footplate helps set the inner ear fluids into motion.


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