Omohyoid muscle 894700 221828428 2008-06-26T08:09:32Z Vedran12 7322109 interwiki hr {{Muscle infobox | Name = Omohyoid muscle | Latin = musculus omohyoideus | GraySubject = 112 | GrayPage = 392 | Image = Gray1210.png | Caption = Side of neck, showing chief surface markings. (Omohyoideus visible at center.) | Image2 = Musculus omohyoideus.png | Caption2 = Muscles of the neck. Anterior view. Omohyoid is labeled on both sides. | Origin = [[Upper border of the scapula]] | Insertion = [[Hyoid bone]] | Action = Depresses the larynx and hyoid bone. Also carries hyoid bone backward and to the side. | Blood = | Nerve = [[Ansa cervicalis]] | MeshName = | MeshNumber = | DorlandsPre = m_22 | DorlandsSuf = 12549956 | }} The '''omohyoid muscle''' is a [[muscle]] at the front of the [[neck]] that consists of two bellies separated by an intermediate [[tendon]]. It belongs to the group of [[infrahyoid muscles]]. ==Structure== It arises from the upper border of the [[scapula]], and occasionally from the [[superior transverse scapular ligament]] which crosses the [[scapular notch]], its extent of attachment to the scapula varying from a few millimetres to 2.5 cm. From this origin, the ''inferior belly'' forms a flat, narrow [[fasciculus]], which inclines forward and slightly upward across the lower part of the neck, being bound down to the clavicle by a fibrous expansion; it then passes behind the [[sternocleidomastoideus]], becomes tendinous and changes its direction, forming an obtuse angle. It ends in the ''superior belly'', which passes almost vertically upward, close to the lateral border of the [[sternohyoideus]], to be inserted into the lower border of the body of the [[hyoid bone]], lateral to the insertion of the [[sternohyoideus]]. The central [[tendon]] of this muscle varies much in length and form, and is held in position by a process of the deep cervical fascia, which sheaths it, and is prolonged down to be attached to the [[clavicle]] and first rib; it is by this means that the angular form of the muscle is maintained. ==Triangles== The inferior belly of the Omohyoideus divides the [[posterior triangle of the neck]] into an upper or [[occipital triangle]] and a lower or [[subclavian triangle]]. Its superior belly divides the [[anterior triangle]] into an upper or [[carotid triangle]] and a lower or [[muscular triangle]]. The Omohyoid muscle is proximally attached to the [[scapula]] and distally attached to the [[hyoid bone]]. ==Variations== Doubling; absence; origin from clavicle; absence or doubling of either belly. ==Innervation== The omohyoid is innervated by a branch of the [[cervical plexus]], and mostly acts to stabilise the hyoid bone. ==Additional images== <gallery> Image:Gray186.png|Hyoid bone. Anterior surface. Enlarged. Image:Gray203.png|Left scapula. Dorsal surface. Image:Gray384.png|Section of the neck at about the level of the sixth cervical vertebra. Showing the arrangement of the fascia coli. Image:Gray385.png|Muscles of the neck. Lateral view. Image:Gray507.png|Superficial dissection of the right side of the neck, showing the carotid and subclavian arteries. Image:Gray558.png|The veins of the neck, viewed from in front. Image:Gray794.png|Hypoglossal nerve, cervical plexus, and their branches. Image:Gray808.png|The right brachial plexus with its short branches, viewed from in front. Image:Musculi colli omohyoideus.svg|Musculi colli omohyoideus </gallery> The omohyoid muscle is innervated by the ansa cervicalis from the cervical plexus (C1-3) ==External links== * {{GPnotebook|-1335164848}} * {{SUNYAnatomyLabs|24|06|01|00}} * {{SUNYAnatomyFigs|24|01|09}} * {{MuscleLoyola|omo}} * {{NormanAnatomy|lesson6}} {{Gray's}} {{Muscles of neck}} [[Category:Muscles of the head and neck]] {{muscle-stub}} [[de:Musculus omohyoideus]] [[es:Omohioideo]] [[hr:Ramenopodjezični mišić]] [[ja:肩甲舌骨筋]] [[pl:Mięsień łopatkowo-gnykowy]] [[sr:Омохиоидни мишић]]