Incus

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Bone: Incus

Left incus. A. From within. B. From the front.

Auditory tube, laid open by a cut in its long axis.
Malleus Tensor Tympani Incus Stapedius Labyrinth Stapes Auditory Canal Tympanic Membrane (Ear Drum) Eustachian Tube Tympanic cavity
Bones and muscles in the tympanic cavity in the middle ear
Gray's	subject #231 1044
Precursor	1st branchial arch^[1]
MeSH	Incus

For the record label, see Incus Records.

The incus or anvil is the anvil-shaped small bone or ossicle in the middle ear. It connects the malleus to the stapes. It was first described by Alessandro Achillin of Bologna.

The incus transmits sound vibrations from the malleus to the stapes.

The incus only exists in mammals, and is derived from a reptilian upper jaw bone, the quadrate bone.

1 Additional images
2 See also
3 References
4 External links

[edit] Additional images

Head and neck of a human embryo eighteen weeks old, with Meckel’s cartilage and hyoid bar exposed.

External and middle ear, opened from the front. Right side.

Chain of ossicles and their ligaments, seen from the front in a vertical, transverse section of the tympanum.

Ossicles

[edit] See also

[edit] References

^ hednk-023 — Embryology at UNC

[edit] External links

The Anatomy WizIncus

v • d • e Sensory system: Auditory and Vestibular systems

Outer ear	Pinna (Helix, Antihelix, Tragus, Antitragus, Earlobe) • Ear canal

Middle ear	Eardrum (Umbo) • Ossicles (Malleus, Incus & Stapes) • muscles (Stapedius, Tensor tympani) • Eustachian tube (Torus tubarius)

Inner ear/Labyrinth	Bony labyrinth (Vestibule) • Membranous labyrinth Oval window → Scala vestibuli / Reissner's/vestibular membrane, Helicotrema and Scala tympani / Basilar membrane (Perilymph) → Round window Cochlea: Modiolus • Cochlear duct / scala media (Endolymph, Stria vascularis, Spiral ligament, Organ of Corti), Olivocochlear system Organ of Corti: Stereocilia • Sulcus spiralis (externus, internus) • Limbus spiralis

to brain (auditory)	Tectorial membrane → Hair cells → Spiral ganglion → Cochlear nerve ^VIII → Cochlear nuclei → Trapezoid body → Superior olivary nuclei → Lateral lemniscus → Inferior colliculi → Medial geniculate nuclei → Auditory radiations → Primary auditory cortex

Vestibular system	Static/translations: Utricle (Macula) – Saccule (Macula, Endolymphatic sac, Endolymphatic duct) – Kinocilium – Otolith Kinetic/rotations: Semicircular canals (Superior, Posterior, Horizontal) • Cupula • Ampullae (Crista ampullaris)

to brain (vestibular)	Vestibular nerve ^VIII → Vestibular nuclei, Flocculonodular lobe Vestibular nuclei → Vestibulospinal tract, Ventral posterolateral nucleus → Vestibular cortex

v • d • e Bones (Axial skeleton, Appendicular skeleton)

VERTEBRAL COLUMN	vertebrae (cervical - thoracic - lumbar) - sacrum - coccyx

THORAX	sternum - rib

cranial bones of SKULL	occipital - parietal - frontal - temporal - sphenoid - ethmoid

facial bones of SKULL	nasal - maxilla - lacrimal - zygomatic - palatine - inferior nasal conchae - vomer - mandible - THROAT: hyoid (greater cornu, lesser cornu, body)

UPPER EXTREMITY	SHOULDER GIRDLE:clavicle - scapula - ARM: humerus - ulna - radius- HAND:carpals (scaphoid - lunate bone - triquetral - pisiform - trapezium - trapezoid - capitate - hamate) - metacarpals - phalanges (prox - int - dist)

LOWER EXTREMITY	PELVIS:pelvis (ilium, ischium, pubis) - LEG: femur - patella - fibula - tibia - FOOT: tarsals (calcaneus - talus - navicular - cuneiform - cuboid ) - metatarsals - phalanges (prox - int - dist)

MIDDLE EAR OSSICLES	malleus - incus - stapes