adj.

胸鎖乳突筋の

関: musculus sternocleidomastoideus、sternocleidomastoid muscle、sternocleidomastoideus、sternomastoid

WordNet

one of two thick muscles running from the sternum and clavicle to the mastoid and occipital bone; turns head obliquely to the opposite side; when acting together they flex the neck and extend the head (同)sternocleidomastoid_muscle, sternocleido mastoideus, musculus_sternocleidomastoideus
drains the sternocleidomastoid muscle; empties into the internal jugular vein (同)vena sternocleidomastoidea

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出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2015/01/19 11:26:32」(JST)

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In human anatomy, the sternocleidomastoid muscle /ˌstɜrnɵˌkliːdɵˈmæstɔɪd/, also known as sternomastoid and commonly abbreviated as SCM, is a paired muscle in the superficial layers of the anterior portion of the neck; it is one of the largest and most superficial cervical muscles.

Structure

The sternocleidomastoid passes obliquely across the side of the neck.

It is thick and narrow at its central part, but broader and thinner at either end.

The medial or sternal head is a rounded fasciculus, tendinous in front, fleshy behind, which arises from the upper part of the anterior surface of the manubrium sterni, and is directed superiorly, laterally, and posteriorly.

The lateral or clavicular head, composed of fleshy and aponeurotic fibers, arises from the superior border and anterior surface of the medial third of the clavicle; it is directed almost vertically upward.

The two heads are separated from one another at their origins by a triangular interval (supraclavicular fossa) but gradually blend, below the middle of the neck, into a thick, rounded muscle which is inserted, by a strong tendon, into the lateral surface of the mastoid process, from its apex to its superior border, and by a thin aponeurosis into the lateral half of the superior nuchal line of the occipital bone.

Innervation

The sternocleidomastoid is innervated by the ipsilateral accessory nerve. It supplies only motor fibres. The cervical plexus supplies sensation, including proprioception, via the ventral primary rami of C2 and C3.

Variations

The sternocleidomastoid varies much in the extent of its origin from the clavicle: in some cases the clavicular head may be as narrow as the sternal; in others it may be as much as 7.5 centimetres (3.0 in) in breadth.

When the clavicular origin is broad, it is occasionally subdivided into several slips, separated by narrow intervals. More rarely, the adjoining margins of the sternocleidomastoid and trapezius are in contact. This would leave no posterior triangle.

The supraclavicularis muscle arises from the manubrium behind the sternocleidomastoid and passes behind the sternocleidomastoid to the upper surface of the clavicle.

Relations

The sternocleidomastoid is within the investing fascia of the neck, along with the trapezius muscle, with which it shares its nerve supply (the accessory nerve). It is thick and thus serves as a primary muscular landmark of the neck during an extraoral examination of a patient since it divides the neck region into anterior and posterior cervical triangles which helps define the location of structures, such as the lymph nodes for the head and neck.^[1] Anterior to sternocleidomastoid is the anterior triangle. Posterior to it is the posterior triangle.

Many important structures relate to the sternocleidomastoid, including the common carotid artery, accessory nerve, and brachial plexus.

Function

The function of this muscle is to rotate the head to the opposite side or obliquely rotate the head. It also flexes the neck. When acting together it flexes the neck and extends the head. When acting alone it rotates to the opposite side (contralaterally) and slightly (laterally) flexes to the same side.

It also acts as an accessory muscle of inspiration, along with the scalene muscles of the neck.

History

Etymology

It is given the name sternocleidomastoid because it originates at the manubrium of the sternum (sterno-) and the clavicle (cleido-), and has an insertion at the mastoid process of the temporal bone of the skull.

Clinical significance

Examination

The SCM is effectively palpated on each side of the neck when the patient moves the head to the contralateral side.^[1]

Society and culture

In Tom Wolfe's novel The Bonfire of the Vanities, Larry Kramer, a Bronx District Attorney and one of the novel's main protagonists, prides himself on his strong sternocleidomastoids, which he "fans out" in front of women to help give himself a more tough, masculine appearance. However, in the last chapter he is publicly described by his client Maria Ruskin as "doing something weird with his neck", which deeply wounds his ego. Its use here is possibly a dramatic device signalling the lengths ambitious men go to, looking after every meticulous detail, in order to appear powerful, or how some women respond to such details and others not.
Creature designers often include the sternocleidomastoid muscle in models of alien characters when they want them to seem attractive and familiar to human viewers due to the muscle's uniqueness as a mammalian feature. "Even C-3PO has it, in the form of little pistons on his neck. Watch Star Trek: The good guys always have them, and the bad guys don't. It's a classic alien designer trick," notes biologist and Hollywood anatomy consultant Stuart Sumida.^[2]
The famous Argentinian comedy/musical group Les Luthiers mention the sternocleidomastoid muscle in their song "El negro quiere bailar". The main actor (Daniel Rabinovich) is asked to move his sternocleidomastoid muscle as part of a dance class, but he erroneously interprets it as a pelvic/genital body part, and nervously covers himself with his arms.^[3]

Additional images

Muscles connecting the upper extremity to the vertebral column. The posterior surface of the sternocleidomastoid muscle is labeled.
Position of sternocleidomastoid muscle. Animation.
Anterior surface of sternum and costal cartilages
Occipital bone, outer surface
Left temporal bone, outer surface
Base of skull, inferior surface
Left clavicle, superior surface
Section of the neck at about the level of the sixth cervical vertebra
Superficial dissection of the right side of the neck, showing the carotid and subclavian arteries
Veins of the head and neck
The veins of the neck, viewed from in front
The nerves of the scalp, face, and side of neck
Anterolateral view of head and neck
Front view of neck
surface anatomy
Sternocleidomastoid muscle
Sternocleidomastoid muscle, lateral view
SCM
SCM – right view

References

This article incorporates text from a public domain edition of Gray's Anatomy.

^ ^a ^b Illustrated Anatomy of the Head and Neck, Fehrenbach and Herring, Elsevier, 2012, page 87
^ Nina Shen Rastogi (December 16, 2009). "On Na'vi Biology". Slate Magazine. The Washington Post Company. Retrieved December 21, 2009.
^ Les Luthiers. "El negro quiere bailar (YouTube)".

External links

Wikimedia Commons has media related to Sternocleidomastoid muscles.

Origin, insertion and nerve supply of the muscle at Loyola University Chicago Stritch School of Medicine
436600910 at GPnotebook
Anatomy figure: 24:01-03 at Human Anatomy Online, SUNY Downstate Medical Center
Sternocleidomastoid+muscle at eMedicine Dictionary
Anatomy diagram: 25420.000-1 at Roche Lexicon - illustrated navigator, Elsevier

UpToDate Contents

全文を閲覧するには購読必要です。 To read the full text you will need to subscribe.

1. 頸部の疼痛または損傷がみられる小児または思春期のアスリートに対するアプローチ approach to the child or adolescent athlete with neck pain or injury
2. 頚部腫瘤の鑑別診断 differential diagnosis of a neck mass
3. 先天性筋性斜頚 congenital muscular torticollis
4. 後頭神経痛 occipital neuralgia
5. 成人における詳細な神経学的検査 the detailed neurologic examination in adults

English Journal

Saccular sensitivity function measured by vestibular evoked myogenic potential.

de Oliveira Barreto AC, Colafemina JF, de Lemos Menezes P.SourceFederal Universit of Sergipe.
Acta oto-laryngologica." abstractLink="yes" alsec="jour" alterm="Acta Otolaryngol.2011 Jun;131(6):618-23. Epub 2011 Feb 14.
Abstract Conclusions: Vestibular myogenic potential responses were present when evoked by tone burst stimuli of 250, 500, 1000, and 2000 Hz; however, they were more effective for low-frequency stimuli. Objectives: Few studies refer to specific frequency sensitivities of the saccular afferents. Accor
PMID 21319943

An estimation of right- and left-sided central venous catheter insertion depth using measurement of surface landmarks along the course of central veins.

Kim MC, Kim KS, Choi YK, Kim DS, Kwon MI, Sung JK, Moon JY, Kang JM.SourceDepartment of Anesthesiology, Kyung Hee University, East-West Neo Medical Center, 149 Sangil-dong Gangdong-Gu, Seoul, Korea, 134-090. kjm@khnmc.or.k.
Anesthesia and analgesia." abstractLink="yes" alsec="jour" alterm="Anesth Analg.2011 Jun;112(6):1371-4. Epub 2011 Jan 13.
PMID 21233490

Multiple active myofascial trigger points reproduce the overall spontaneous pain pattern in women with fibromyalgia and are related to widespread mechanical hypersensitivity.

Alonso-Blanco C, Fernandez-de-Las-Penas C, Morales-Cabezas M, Zarco-Moreno P, Ge HY, Florez-Garcia M.SourceDepartments of *Health Sciences II †Physical Therapy, Occupational Therapy, Rehabilitation and Physical Medicine ‡Esthesiology Laboratory, Universidad Rey Juan Carlos Departments of ∥Rheumatology ¶Rehabilitation, Fundacion Hospital Alcorcon, Alcorcon, Madrid, Spain §Centre for Sensory-Motor Interaction (SMI), Department of Health Science and Technology, Aalborg University, Aalborg, Denmark.
The Clinical journal of pain." abstractLink="yes" alsec="jour" alterm="Clin J Pain.2011 Jun;27(5):405-13.
PMID 21368661

Japanese Journal

下顎部および頸部に生じた鰓裂由来の側頸瘻・側頸嚢胞の2症例

後藤浩之,仲沢弘明,本田隆司,下田勝巳,櫻井裕之
東京女子医科大学雑誌 80(12), 370-375, 2010-12-25
頸瘻・側頸嚢胞は、胎生期に鰓弓を分けている鰓裂の遺残に起因する先天性疾患であり、発生頻度は10万人に1人とされ、本邦でもその報告が散見されるが、形成外科領域においてはいまだ比較的稀な疾患である。今回、我々は発生由来の異なる側頸瘻・側頸嚢胞の2症例を治療する経験を得たので、若干の文献的考察を加えて報告する。症例1:34歳、女性。幼少時より下顎部に腫瘤を認め、排膿を繰り返していた。MRIにて耳下腺浅葉 …
NAID 110007881699

新しいVEMPの検査法

室伏利久
Equilibrium research 69(3), 182-187, 2010-06-01
… The author showed variants of the vestibular evoked myogenic potential (VEMP), which have been developed as a myogenic potential evoked on the sternocleidomastoid muscle by air-conducted sound (ACS). …
NAID 10026700941

耳石機能検査としてのVEMP

將積日出夫
Equilibrium research 69(3), 168-175, 2010-06-01
… In humans, a positive followed by a negative waveform with short latency is reproducibly evoked in the sternocleidomastoid (SCM) muscle in response to intense sound. …
NAID 10026700891

Related Pictures

★リンクテーブル★

リンク元	「胸鎖乳突筋」「sternomastoid」

「胸鎖乳突筋」

Sternocleidomastoid
	Muscles of the neck. Lateral view.
	The sternocleidomastoid muscle with nearby structures labeled, such as the triangles of the neck.
Details
Latin	Musculus sternocleidomastoideus
Origin	Manubrium sterni and medial portion of the clavicle
Insertion	Mastoid process of the temporal bone, superior nuchal line
Artery	Occipital artery and the superior thyroid artery
Nerve	Motor: accessory nerve; sensory: cervical plexus
Actions	Unilaterally; cervical rotation to opposite side, cervical lateral flexion to same side Bilaterally; cervical flexion, raises the sternum and assists in forced inspiration.
Identifiers
Gray's	p.390
Dorlands; /Elsevier	m_22/12550942
TA	A04.2.01.008
FMA	FMA:13407
	Anatomical terms of muscle