Prostheses in the ossicular chain. I. Mechanics of movement.

The ossicular chain works like a lever. The axis seems to shift depending on the frequency in which the system is swinging. By physiological sound pressure the malleus and incus move as one body. The stapes seems to move mainly as a piston in the oval window. The speed of the stapes increases with approximately 6 dB/octave by frequencies under the resonance point and decreases with 6 dB/octave over the resonance point. The mechanical system of the ear is of importance for the sensitivity of the ear.