{{Short description|Small pyramidal slip of muscle deep to the superior orbital nerve, artery and vein}} {{Infobox muscle | Name = Procerus muscle | Latin = musculus procerus, pyramidalis nasi, depressor glabellae | Image = Procerus.png | Caption = Muscles of the head, face, and neck (Procerus visible at upper left, at top of nose) | Origin = From fascia over the lower part of the nasal bone | Insertion = Into the skin of the lower part of the forehead between the eyebrows | Blood = Facial artery | Nerve = Temporal branch of the facial nerve | Action = Draws down the medial angle of the eyebrow giving expressions of frowning }}
The '''procerus muscle''' (or '''pyramidalis nasi''') is a small pyramidal muscle in the glabella. It is involved in facial expressions such as frowning and those associated with attentional control, and it indirectly helps shield the eyes from bright light. Because it contributes to wrinkle formation on the nasal bridge, it is often targeted in non-surgical facial rejuvenation treatments, such as botulinum toxin injections.<ref name="Gray2016">{{cite book |editor-last=Standring |editor-first=Susan |editor-link=Susan Standring |last=Hopkins |first=Claire |author-link=Claire Hopkins |title=Gray's Anatomy: The Anatomical Basis of Clinical Practice |chapter=Chapter 33. Nose, nasal cavity and paranasal sinuses |edition=41st |year=2016 |publisher=Elsevier |isbn=9780702052309}}</ref>{{rp|page=558}} ''Procerus'' is Latin, meaning tall or extended.
==Structure== The procerus muscle arises by tendinous fibers from the fascia covering the lower part of the nasal bone and upper part of the lateral nasal cartilage. It is inserted into the skin over the lower part of the forehead between the two eyebrows on either side of the midline, its fibers merging with those of the frontalis muscle.<ref>"eye, human."Encyclopædia Britannica from Encyclopædia Britannica 2006 Ultimate Reference Suite DVD 2009</ref>
=== Nerve supply === The procerus muscle is supplied by the temporal branch of the facial nerve (VII).<ref name=":0">{{cite journal |last1=Caminer |first1=D.M. |last2=Newman |first2=M.I. |last3=Boyd |first3=J.B. |title=Angular nerve: New insights on innervation of the corrugator supercilii and procerus muscles |journal=Journal of Plastic, Reconstructive & Aesthetic Surgery |date=April 2006 |volume=59 |issue=4 |pages=366–372 |doi=10.1016/j.bjps.2005.09.011 |pmid=16756251 }}</ref> It may also be supplied by other branches of the facial nerve, which can be varied,<ref name=":0" /> including the lower zygomatic branches. A supply from its buccal branch has also been described.<ref>"Nose, nasal cavity and paranasal sinuses" CHAPTER 32. Gray's Anatomy</ref> Its contraction can produce transverse wrinkles.
==Function== The procerus muscle helps to pull that part of the skin between the eyebrows downwards, which assists in flaring the nostrils. It can also contribute to an expression of anger.
== Clinical significance == === Procerus sign === {{Main articles|procerus sign}}
Dystonia of the procerus muscle is involved in the procerus sign, which is indicative of progressive supranuclear palsy (PSP).<ref>{{cite journal |last1=Batla |first1=Amit |last2=Nehru |first2=Ravi |last3=Vijay |first3=Tarun |title=Vertical wrinkling of the forehead or Procerus sign in Progressive Supranuclear Palsy |journal=Journal of the Neurological Sciences |date=November 2010 |volume=298 |issue=1–2 |pages=148–149 |doi=10.1016/j.jns.2010.08.010 |pmid=20810128 }}</ref>
=== Denervation === The procerus muscle may be denervated to reduce furrow lines around the glabella caused by frowning.<ref name=":0" /> This may be for cosmetic purposes. Surgery can be used to transect the temporal branch of the facial nerve, although other branches of the facial nerve may also need to be cut.<ref name=":0" />
==Additional images== <gallery> File:Procerus muscle animation small.gif|Procerus muscle (red). </gallery>
==References== {{Gray's}} {{Reflist}}
{{Muscles of head}} {{Portal bar|Anatomy}} {{Authority control}}
Category:Muscles of the head and neck Category:Human head and neck Category:Facial muscles