Muscle groups of the neck

  • Post-vertebral muscles
  • Anterior vertebral muscles
  • Lateral vertebral muscles
  • Anterior neck muscles
  • Superficial neck muscles

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*Refer medical museum models

Anterior vertebral muscles

  • Muscles
    • Rectus capitis anterior
    • Longus capitis
    • Longus colli
  • Attachment
    • base of the skull & bodies
    • transverse processes of cervical
    • upper 4 thoracic vertebrae
  • Nerve supply
    • C1 – C6
  • Action
    • flex head & neck

Lateral vertebral muscles

  • Muscles
    • Rectus capitis lateralis
    • Levator scapulae
    • Anterior scalene
    • Middle scalene
    • Posterior scalene
  • Attachments
    • vary
  • Nerve supply
    • C1 – C8
  • Actions
    • vary

Anterior neck muscles

  • Above hyoid bone (suprahyoid)
  1. Mylohyoid
  • Origin
    • mylohyoid line of mandible
  • Nerve supply
    • Mandibular division of 5th CN
  • Action
    • Elevates floor of mouth (Swallowing)
  • Digastric (ant & post bellies)
    • Origin
      • digastic fossa (anterior belly)
      • mastoid process (posterior belly)
    • Insertion
      • intermediate tendon to greater horn & body
    • Nerve supply
      • Anterior belly: mandibular division of 5th CN
      • Posterior belly: facial nerve
    • Actions
      • depresses the mandible (open mouth)
      • elevates the hyoid bone on swallowing
  • Below hyoid bone (infrahyoid)
    • Strap muscles
    1. Sternohyoid
    • Origin
      • manubrium
    • Insertion
      • body of hyoid
    • Nerve supply
      • ansa cervicalis (C1-C3)
    • Action
      • depresses the hyoid after elevation during swallowing
  • Omohyoid
    • Origin
      • Superior border of scapula
    • Insertion
      • body of hyoid
    • Nerve supply
      • Ansa cervicalis (C1-C3)
    • Action
      • same as above
  • Sternothyroid
    • Origin
      • manubrium
    • Insertion
      • obliqueline of thyroid cartilage
    • Nerve supply
      • Ansa cervicalis (C2-C3)
    • Action
      • same as above
  • Thyrohyoid
    • Origin
      • oblique line of thyroid cartilage
    • Insertion
      • body of hyoid
    • Nerve supply
      • Ansa cervicalis (C1 – via hypoglossal nerve)
    • Action
      • same as above
      • elevates the larynx*

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    Superficial neck muscles

    1. Sternocleidomastoid muscle
    • Key muscle of the neck
    • Anterior to it
      • anterior triangle
    • Posterior to it
      • posterior triangle
    • Origins of 2 heads
      • sternal head
        • manubrium sterni
      • clavicular head
        • superior surface of medial end of clavicle
    • Insertion
      • mastoid process
      • lateral half of superior nuchal line
    • Nerve supply
      • spinal accessory nerve (11th CN)
    • Actions
      • Unilateral contraction
        • tilts the head to the same side & rotate
          • face turned upwards to opposite side
      • Bilateral contraction
        • extends neck at atlanto-occipital joint
        • flexes the cervical spine anteriorly
          • looking at the strs
  • Trapezius
    • Large flat triangular muscle
    • Extends covering the cervical region & thorax
    • Origin
      • Medial 3rd of superior nuchal line
      • External occipital protuberance
      • Nuchal ligament
      • Spines of C7 downwards
    • Insertion
      • spine of the scapula
      • Acromion
      • Lateral 3rd of clavicle
    • Nerve supply
      • spinal accessory nerve (same as SCM)
    • Actions
      • Elevates scapula (superior fibres)
      • Retracts scapula (middle fibres)
      • Depresses scapula (inferior fibres)
      • Rotates scapula (superior & inferior fibres)
        • butterfly style of swimming

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    Muscular triangles of the neck

    • Vertebral triangle
      • Gap between anterior scalene & longus colli
      • Bounderies
        • apex: C6 anterior tubercle
        • base: subclavian artery
    • Posterior triangle
      • Occipital & Subclavian triangle
      • Contents*
        • Occipital artery
        • Accessory nerve
        • External jugular vein
        • Subclavian artery
    • Anterior triangle
    1. Submental triangle
    • Borders: digastric (anterior), hyoid bone, mandible
  • Digastric triangle
    • Borders: digastric (anterior), mandible
  • Carotid triangle
    • Borders: digastric (posterior), superior belly of omohyoid
    • Contents*
      • common carotid artery
      • external carotid artery
      • internal jugular vein
      • vagus nerve
  • Muscular triangle
    • Borders: Hyoid, Sternohyoid (2)
    • Contents*
      • larynx
      • t
        rachea
      • thyroid gland


    terri

    Terri is obsessed with making medical school as painless as possible. She studies and compiles medical school notes in a concise, easy-to-understand format. She also enjoys reading contributions by others. She is an investor in sustainability projects. Her ideal weekend is wine tasting and experimenting on bread-making. She has yet to master the art of Sourdough baking.

    1 Comment

    cyline · April 13, 2016 at 12:52 pm

    the information flows

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