BoneIrregular bone

Incus

Latin: Incus sinistrum

Location: Left middle ear

Paired structure: one on the left and one on the right side of the body.

View the incus in 3D

Function

The middle ossicle — an anvil that receives the malleus' swing and passes it through its long process to the stapes, completing the lever system that boosts sound pressure roughly 22-fold overall.

Landmarks

  • Body
  • Short process
  • Long process
  • Lenticular process

Articulations (joints)

  • Malleus (incudomalleolar joint)
  • Stapes (incudostapedial joint)

Clinical relevance

The incus is the ossicle most often eroded by chronic ear disease; ossiculoplasty replaces it with a PORP prosthesis.

Educational anatomy reference, not medical advice. About this content.