In human anatomy, the stapedial branch of

posterior auricular artery The posterior auricular artery is a small artery that arises from the external carotid artery, above the digastric muscle and stylohyoid muscle, opposite the apex of the styloid process. It ascends posteriorly beneath the parotid gland, alo ...

, or stapedial artery for short, is a small artery supplying the

stapedius muscle The stapedius is the smallest skeletal muscle in the human body. At just over one millimeter in length, its purpose is to stabilize the smallest bone in the body, the stapes or strirrup bone of the middle ear. Structure The stapedius emerges from ...

in the

inner ear The inner ear (internal ear, auris interna) is the innermost part of the vertebrate ear. In vertebrates, the inner ear is mainly responsible for sound detection and balance. In mammals, it consists of the bony labyrinth, a hollow cavity in the ...

Structure

In humans

In humans, the stapedial artery is normally present in the

fetus A fetus or foetus (; plural fetuses, feti, foetuses, or foeti) is the unborn offspring that develops from an animal embryo. Following embryonic development the fetal stage of development takes place. In human prenatal development, fetal develo ...

where it connects what is to become the external and internal carotid arteries. Part of the carotid artery system, it originates from the dorsal branch of

aortic arch The aortic arch, arch of the aorta, or transverse aortic arch () is the part of the aorta between the ascending and descending aorta. The arch travels backward, so that it ultimately runs to the left of the trachea. Structure The aorta begins a ...

. Its superior supraorbital branch becomes the

middle meningeal artery The middle meningeal artery ('' la, arteria meningea media'') is typically the third branch of the first portion of the maxillary artery. After branching off the maxillary artery in the infratemporal fossa, it runs through the foramen spinosum to ...

, while its infraorbital and mandibular branches fuses with the external carotid artery and later become the

internal maxillary artery The maxillary artery supplies deep structures of the face. It branches from the external carotid artery just deep to the neck of the mandible. Structure The maxillary artery, the larger of the two terminal branches of the external carotid artery, ...

. Its trunk atrophies and is replaced by branches from the external carotid artery. In rare cases, the embryonic structure is still present after birth in which case it is referred to as a persistent stapedial artery (PSA). While the prevalence of this anomaly is unknown, it has been estimated to be present in 1 of 5,000 people.

In other mammals

Structures homologous to the stapedial artery in humans and other primates can be derived from a primitive, hypothetical pattern similar to that found in primitive rodents: the stapedial artery enters the

middle cranial fossa The middle cranial fossa, deeper than the anterior cranial fossa, is narrow medially and widens laterally to the sides of the skull. It is separated from the posterior fossa by the clivus and the petrous crest. It is bounded in front by the po ...

and splits into the anterior and inferior divisions of the superior ramus and the inferior ramus. The inferior ramus has been lost in strepsirhines while the stem of the stapedial artery has been reduced in haplorhines.

Notes

References

* * * {{Authority control Arteries of the head and neck