Triangles Of The Neck Flashcards
Mandible has what two lines?
Digastric and mylohyoid lines
Name the 2 deep muscles the neck
Scalenes and prevertebral muscles
Scalenes are homologous to which muscles located in a different part of the body
Hypaxial body wall musculature
2 intermediate muscles of the neck
Suprahyoid and infrahyoid muscles
- Suprahyoid muscles extend between
2. Infrahyoid muscles extend between
- Hyoid and skull
2. Hyoid and cartilages of trunk
3 superficial muscles of the neck
Trapezius, SCM and platysma
Trapezius and SCM have 2 innervations; what are they
Spinal accessory nerve (CN XI)(main) and cervical rami
All the triangles of the neck are based on relation to ?
SCM
Boundaries of the anterior triangle
Anterior triangle has 2 subsections of triangles. What are these triangles called
SCM, anterior midline of neck, and mandible
Submental triangle and digastric triangle
Boundaries of the submental triangle
Hyoid, digastric, and mylohyoid
Boundaries of digastric triangle
Mandible, digastric, and mylohyoid
Boundaries of the posterior triangle (this is not a subsection; this is its own triangle)
Anterior trapezius, posterior SCM, and clavicle
SCM
- Origin
- Insertion
- Innervation
- Action
- Manubrium (sternal head); medial clavicle (clavicular head)
- Mastoid process and superior nuchal line
- CN XI
- Rotates head, laterally flexes neck, anteriorly flexes cervical vertebrae, and extends atlanto-occipital joint
What are the 4 suprahyoid muscles?
Geniohyoid, mylohyoid, digastric and stylohyoid
Geniohyoid
- Origin
- Insertion
- Innervation
- Action
- Internal mandibular symphysis
- Body of hyoid
- C1 via hypoglossal nerve
- Elevates hyoid
Mylohyoid
- Origin
- Insertion
- Innervation
- Action
- Mylohyoid on the interior of the mandible
- Body of hyoid
- CN V3
- Elevates hyoid, raises floor of mouth
Digastric
- Origin
- Insertion
- Innervation
- Action
- Digastric notch medial to mastoid (posterior), internal mandibular symphysis (anterior)
- Digastric tendon
- CN V3 (anterior), CN VII (posterior)
- Assists in opening the mouth, elevates hyoid
Stylohyoid
- Origin
- Insertion
- Innervation
- Action
- Styloid process of temporal bone
- Body of hyoid
- CN VII
- Elevates hyoid bone; assists in opening mandible
Name the 4 infrahyoid (strap) muscles
Sternohyoid, omohyoid, sternothyroid, and thyrohyoid
Sternohyoid
- Origin
- Insertion
- Innervation
- Action
- Manubrium
- Body of hyoid
- Ansa cervicalis C1-C3
- Depresses hyoid and larynx
Omohyoid
- Origin
- Insertion
- Innervation
- Action
- Upper border of scapula
- Body of hyoid
- Ansa cervicalis C1-C3
- Depresses hyoid and larynx
Sternothyroid
- Origin
- Insertion
- Innervation
- Action
- Manubrium
- Oblique line on lamina of thyroid cartilage
- Ansa cervicalis C1-C3
- Depresses thyroid cartilage and larynx
Thyrohyoid
- Origin
- Insertion
- Innervation
- Action
- Oblique line on lamina of thyroid cartilage
- Greater horn of hyoid
- C1 hypoglossal nerve
- Depresses hyoid; elevates thyroid
Posterior triangle contains structures that are going where?
To upper limb
- What forms the interscalene triangle?
- What passes through this triangle?
- What is at the bottom of this triangle?
- What does the anterior scalene form at its origin?
- Anterior scalene and middle scalene
- Cervical ventral rami and subclavian artery and T1 ventral ramus inferiorly
- Subclavian vein (passes anterior to anterior scalene across 1st rib)
- Scalene tubercle (on 1st rib)
What muscles of the neck are considered non triangle muscles?
Prevertebral muscles
Anterior scalene
- Origin
- Insertion
- Innervation
- Action
- 1st rib
- Anterior tubercles of C3-C6
- C4-C7
- Lateral flexion of neck and elevation of ribcage
Middle scalene
- Origin
- Insertion
- Innervation
- Action
- 1st rib
- Posterior tubercles of C2-C7
- C3-C7
- Lateral flexion of neck and elevation of ribcage
Posterior scalene
- Origin
- Insertion
- Innervation
- Action
- 2nd rib
- Posterior tubercles of C4-C6
- C5-C7
- Lateral flexion of neck and elevation of the ribcage
Prevertebral muscles - Longus Capitis
- Origin
- Insertion
- Innervation
- Action
- Cervical vertebrae
- Occipital bone
- C1-C4
- Anterior flexion of neck
Prevertebral muscles- longus colii
- Origin
- Insertion
- Innervation
- Action
- Thoracic and cervical vertebrae
- Cervical vertebrae
- C2-C8
- Anterior flexion of neck
2 sources of innervation:
- Hypaxial strap muscles get their innervation from?
- Branchial muscles get their innervation from?
- Ventral rami of C1-C4 spinal nerves (cervical plexus and superficial innervation)
- CN VII, X, XI, and XII
- What is the main part of the cervical plexus?
- What is it formed by?
- What does it supply
- Ansa cervicalis
- Two looping nerve connections between descendens hypoglossi and descendens cervicalis
- Infrahyoid muscles
Descenden hypoglossi
- How does it run
- Where does it come from
- Along hypoglossal nerve superiorly
2. C1
Descendens cervicalis
- Where does it come from
- How does it run
- C2-C3
2. Posterior to internal jugular
What two muscles are supplied by C1?
C1 branches follow the path of the
Geniohyoid and thyrohyoid muscles
Hypoglossal nerve
C1-C4 give off short branches to what 2 muscles?
Adjacent prevertebral and scalene muscles
C4-C5 contribute to?
Brachial plexus
What provides superficial innervation in the neck
What are these 3 nerves
Where do you look for these 3 nerves?
Branches that emerge from loop connecting C2-C3
Lesser occipital nerve, greater auricular nerve, and transverse cervical nerve
Posterior to SCM
One more superficial nerve emerges from ___; what is this nerve called?
Supraclavicular nerve; emerges from loop connecting C3-C4