Incus

The anvil (Latin incus, incudis f ) is a small bone in the middle ear of mammals and is one of the ossicles. It lies between the hammer and the stirrup and is responsible for the transmission of the sound is important.

Phylogenesis

The anvil is formed embryonic from the upper part of the first gill arch, called the palatoquadrate. In the non-mammalian forms the os quadratum still the primary jaw joint and is related to Meckel's cartilage.

Anatomy of the anvil in humans

The anvil in the human ear consists of a body (corpus ) on which there is a joint surface for the articulated connection with the hammer. From the body arises one long and one short leg, crus longum and crus breve. The crus longum ends in lens leg extension ( lenticular process ), which is articulated in conjunction with the stirrups. The length of the body varies from 4.8 to 5.4 mm, the length of the long leg from 4.3 to 5.5 millimeters. The anvil has a mass of about 30 milligrams.