The levator labii superioris (pl. ''levatores labii superioris'', also called quadratus labii superioris, pl. ''quadrati labii superioris'') is a muscle of the

human body The human body is the structure of a human being. It is composed of many different types of cells that together create tissues and subsequently organ systems. They ensure homeostasis and the viability of the human body. It comprises a head ...

used in facial expression. It is a broad sheet, the origin of which extends from the side of the

nose A nose is a protuberance in vertebrates that houses the nostrils, or nares, which receive and expel air for respiration alongside the mouth. Behind the nose are the olfactory mucosa and the sinuses. Behind the nasal cavity, air next passe ...

to the

zygomatic bone In the human skull, the zygomatic bone (from grc, ζῠγόν, zugón, yoke), also called cheekbone or malar bone, is a paired irregular bone which articulates with the maxilla, the temporal bone, the sphenoid bone and the frontal bone. It is si ...

Structure

Its medial fibers form the ''angular head'' (also known as the

levator labii superioris alaeque nasi muscle The levator labii superioris alaeque nasi muscle is, translated from Latin, the "lifter of both the upper lip and of the wing of the nose". It has the longest name of any muscle in an animal. The muscle is attached to the upper frontal process o ...

,) which arises by a pointed extremity from the upper part of the frontal process of the maxilla and passing obliquely downward and lateralward divides into two slips. One of these is inserted into the

greater alar cartilage The major alar cartilage (greater alar cartilage) (lower lateral cartilage) is a thin, flexible plate, situated immediately below the lateral nasal cartilage, and bent upon itself in such a manner as to form the medial wall and lateral wall of t ...

and skin of the nose; the other is prolonged into the lateral part of the upper lip, blending with the infraorbital head and with the

orbicularis oris In human anatomy, the orbicularis oris muscle is a complex of muscles in the lips that encircles the mouth. It is a sphincter, or circular muscle, but it is actually composed of four independent quadrants that interlace and give only an appearance ...

. The intermediate portion or ''infraorbital head'' arises from the lower margin of the orbit immediately above the infraorbital foramen, some of its fibers being attached to the maxilla, others to the

. Its fibers converge, to be inserted into the muscular substance of the upper lip between the angular head and the levator anguli oris. The lateral fibers, forming the ''zygomatic head'' (also known as the

zygomaticus minor muscle The zygomaticus minor muscle is a muscle of facial expression. It originates from the zygomatic bone, lateral to the rest of the levator labii superioris muscle, and inserts into the outer part of the upper lip. It draws the upper lip backward, u ...

) arise from the malar surface of the

immediately behind the zygomaticomaxillary suture and pass downward and medialward to the upper lip.

Function

Its main function is to elevate the upper lip.Clinically Oriented Anatomy 6th ed by Moore & Dalley

Additional images

File:Sobo 1909 262.png File:Sobo 1909 264.png File:Gray157.png, Left maxilla. Outer surface. File:Gray165.png, Left zygomatic bone. Malar surface. File:Gray508.png, The arteries of the face and scalp. File:Frontalis muscle animation small.gif

References

External links

PTCentral
{{Authority control Muscles of the head and neck

Structure

Function

See also

Additional images

References

External links