Incus (Incus)
Educational content only — not medical advice.
Anatomy
The incus is the middle ossicle of the middle ear, anvil-shaped with a body that forms part of the epitympanic recess and two processes (short and long). It articulates anteriorly with the malleus and posteriorly with the stapes at the incudostapedial joint. The long process conducts vibrations to the head of the stapes and is the narrowest part of the ossicular chain — the most common site of ossicular fracture.
Clinical notes
Fracture of the incus long process is the most common ossicular injury after severe head trauma, producing a large conductive hearing loss (up to 50–60 dB) treated with ossiculoplasty. The incudostapedial joint is also eroded in chronic middle-ear infections with cholesteatoma formation.
Related structures
Educational references
FAQ
What is the role of the Incus?
The incus is the middle ossicle of the middle ear, anvil-shaped with a body that forms part of the epitympanic recess and two processes (short and long). It articulates anteriorly with the malleus and posteriorly with the stapes at the incudostapedial joint. The long process conducts vibrations to the head of the stapes and is the narrowest part of the ossicular chain — the most common site of ossicular fracture.
Why is the Incus clinically important?
Fracture of the incus long process is the most common ossicular injury after severe head trauma, producing a large conductive hearing loss (up to 50–60 dB) treated with ossiculoplasty. The incudostapedial joint is also eroded in chronic middle-ear infections with cholesteatoma formation.
Source & license
Derived from Z-Anatomy (Gauthier Kervyn et al.), CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0/); upstream geometry from BodyParts3D, © The Database Center for Life Science. license details