Platysma muscle 2207724 221276149 2008-06-23T20:35:52Z Vedran12 7322109 interwiki hr :''Platysma is also a plant taxon synonym with [[Podochilus]], an orchid genus.'' {{Infobox Muscle | Name = {{PAGENAME}} | GraySubject = 110 | GrayPage = 387 | Image = Platysma.png | Caption = Platysma is visible at bottom, in neck | Origin = inferior [[clavicle]] and fascia of chest| Insertion = [[mandible]] | Blood = |inferior thyroid atery | Nerve = [[cervical branch]] of the [[facial nerve]] (CN VII) | Action = Draws the corners of the [[mouth]] [[inferiorly]] and widens it (as in expressions of sadness and fright). Also draws the [[skin]] of the [[neck]] [[superiorly]] when [[teeth]] are clenched| Antagonist = [[Masseter muscle|Masseter]], [[Temporalis muscle|Temporalis]] | DorlandsPre = p_23 | DorlandsSuf = 12646241 | }} The platysma is a [[superficial]] [[muscle]] that overlaps the [[sternocleidomastoid]]. It is a broad sheet arising from the [[fascia]] covering the upper parts of the [[Pectoralis major]] and [[Deltoideus]]; its fibers cross the [[clavicle]], and proceed obliquely upward and medialward along the side of the neck. The anterior fibers interlace, below and behind the [[symphysis menti]], with the fibers of the muscle of the opposite side; the posterior fibers cross the [[mandible]], some being inserted into the bone below the oblique line, others into the skin and [[subcutaneous]] tissue of the lower part of the face, many of these fibers blending with the muscles about the angle and lower part of the mouth. Sometimes fibers can be traced to the [[Zygomaticus]], or to the margin of the [[Orbicularis oculi]]. Beneath the Platysma, the external [[jugular]] vein descends from the angle of the mandible to the clavicle. ==Variations== Variations occur in the extension over the face and over the clavicle and shoulder; it may be absent or interdigitate with the muscle of the opposite side in front of the neck; attachment to clavicle, mastoid process or occipital bone occurs. A more or less independent [[fasciculus]], the [[Occipitalis]] minor, may extend from the fascia over the [[Trapezius]] to fascia over the insertion of the [[Sternocleidomastoideus]]. ==Nerve== The Platysma is supplied by the cervical branch of the facial nerve. ==Actions== When the entire Platysma is in action it produces a slight wrinkling of the surface of the skin of the neck in an oblique direction. Its anterior portion, the thickest part of the muscle, depresses the lower jaw; it also serves to draw down the lower lip and angle of the mouth in the expression of melancholy. ==External links== * {{eMedicineDictionary|Platysma+muscle}} ==Additional images== <gallery> Image:Gray176.png|Mandible. Outer surface. Side view. Image:Gray557.png|Veins of the head and neck. Image:Gray790.png|The nerves of the scalp, face, and side of neck. </gallery> ==External links== * {{MuscleLoyola|plat}} * {{GPNotebook|-724565957}} * [http://www.posilovani.net/foto/anatomie/krk/platysma.jpg Image] {{Gray's}} {{Muscles_of_neck}} {{muscle-stub}} [[Category:Muscular system]] [[de:Platysma]] [[es:Platisma]] [[hr:Plosnati mišić]] [[it:Platisma]] [[ja:広頚筋]] [[pl:Mięsień szeroki szyi]] [[sr:Платизма]] [[sv:Platysma]] [[zh:頸闊肌]]