Unit 10: The Neck A Flashcards
What are the two uniquely named cervical vertebrae?
Atlas (first cervical vertebrae)
Axis (Second cervical vertebrae)
What three features distinguish cervical vertebrae from other vertebrae?
Trigingular vertebral foramen
Bifid spinous process
Transverse foramina
What are the unique features of atlas (c1)?
Articulates with the occiput of the head and axis
No vertebrael body and no spinous process
Lateral masses which are connected by an anterior and posterior arch
Each lateral mass has a superior and an inferior articular facet.
What are the features of the anterior arch of the atlas?
Has a facet for articulation with the dens of the axis.
What is the role of the transverse ligament of the atlas?
Secures the attachment of the dens (c2) to the articular facet in the anterior arch of c1.
What are the features of the posterior arch of the atlas?
Has a groove for the vertebral artery and C1 spinal nerve.
What are the identifiable features of the axis (c2)?
Dens or odnotoid process
Superior articular facets
What is the lateral atlanto-axial joints?
Are two in total
Made from the joining of the superior articular facets of C2 and the inferior articular facets on the lateral mass of c1
What makes up the medial atlanto-axial joint and what is its function?
The dens on C2 into the articular facet in the anterior arch of the atlas.
Allows for rotation of the head independently of the torso
What features that other cervical vertebrae have does C1 lack?
Vertebral body
Vertebral arch (hence no spinous process)
What joints join vertebral bodies throughout the vertebral column?
Intervertebral discs - made of fibrocartilage
Known as a symphysis (type of cartilaginous joint)
Vertebral arch - synovial joint type between the superior and inferior articular processes of adjacent vertebrae
What classification of joint is the lateral atlanto-axial joint?
Plane type synovial joint
What classification of joint is the medial atlanto-axial joint?
Pivot type synovial joint
What is the atlanto-occipital joint?
What is its function?
Occur between the superior facets of the lateral massess of the atlas and the occipital condyles at the base of the cranium
Permit flexion at the head - e.g nodding
What classification of joint is the atlanto-occipital joint?
Condyloid type synovial joint
What ligaments are found throughout the entire vertebral column?
Posterior longitudinal
Anterior longitudinal
Ligamentum flavum
Interspinous ligament
Identify the ligaments shown in the image
Red and purple - anterior and posterior longitudinal ligament
Blue - ligamentum flavum
Green - interspinal
Yellow - nuchal ligament in cervical, continuous with the supraspinous through out the rest of the spinal cors
What ligaments are unique to the cervical spinal section of the spinal cord?
Transverse ligament of atlas
Nuchal ligament
What is the function of the nuchal ligament?
Continuous with the surpraspinous ligament
Attaches with the tips of spinous process of C1 to c7
Provides proximal attachment for the rhomboid and trapexius
Limits forward flection of the head and the cervical spine
What is the function of the transverse foramina in the cervical vertebrae?
Passageway for the vertebral artery, vein and sympathetic nerves
What structures pass out of the intervertebral foramen?
Spinal nerves
What are the anomalous anatomical relationships of C7 compared to other cervical vertebrae?
Has a set of spinal nerves originating above and below the the transverse formina (in the intervertebral foramina)
Vertebral artery does not pass through the transverse foramina, rather it passes anterior to it
Why is C7 easy to identify grossly?
Large non bifid spinous process can be palpated on the posterior aspect of the neck
How many spinal nerves are associated with the cervical vertebrae?
8
Originate superior to vertebrae
C7 - one superior and inferior to vertebrae.
What is jefferson fracture of the atlas?
Vertical fall onto an extend neck e,g diving into a shallow pool
Compress the lateral masses of atlas - fracture the anterior and posterior arches
If excessive force can also rapture the transverse ligament of he atlas
Unlikley to damage spinal cord at C1 level due to large foramen but damage may occur later down
What is the clincal significance of a hyperextension/whiplash injury?
Damage to the anterior longitudinal ligament of the spine - acutely painful
Fracutes to C vertebrae are suddenly compressed - little change of spinal cord damage due to large foramina
Anterior dislocation at C2 - spinal cord injury causing death or quadriplegia
dislocation at the C6 and C7 level
What is hangman’s fracture?
Fracute of pars interarticularis (bony column joining superior and inferior articular facets of the axis)
Occurs due to high velocity hyperextension and distraction of the head
Often lethal as force or fracture fragments damage the spinal cord
Deep unconsciousness, respiratory failure and cardiac failure
Why is fracture of the dens important clinically?
Unstable and high risk of avascular necrosis
Distal segment isolated from blood supply
Small risk of spinal cord involvement.
What are the borders of the anterior triangle of the neck>
THe inferior border of the mandible
The midline from the sternum to the mandible
The anterior border of the sternocladomastoid
What forms the boundaries of the posterior triangle of the neck?
The posterior boundary of the sternocleidomastoid
The middle 1/3 of the clavicle
The descending part of the trapezius
What groups of muscles make up the anterior triangle of the neck?
The suprahyoid muscles
The infrhyoid muscles (strap muscles)
What are the two division of the infrahyoid muscles?
The superficial and the deep infrahydoid muscles
What makes up the superficial infrahyoid muscles?
Sternohyoid muscles
Superior belly of omohyoid muscle
What is unique about the structure of the oohyoid muscle?
Superior belly runs superior to the clavicle
Inferior belly runs posterior to the clavice
Are connected by a fascial slingover a ligament intersection to the clavicle
What muscles are part of the deep infrahyoid muscles?
Sternothyroid muscle
Thyrohyoid muscle
What innervates the infrahyoid muscles?
Ansa cervicalis (unification of anterior rami of C1,2,3) - loop of muscles close internal jugular vein
Exception - thyohyoid innervated by anterior rami of C1 carried by the hypoglossal nerve
What is the main action of the inferohyoid muscles?
Depress the hyoid bone
What are the additional function of the sternothyroid muscle?
As an infrahyoid will depress the hyoid
Also depress the thyroid cartilage/larynx
What are the additional function of the thyrodhyoid muscle?
As an infrahyoid will depress the hyoid
Will also elevate the thyroid cartilage
Describe the realtionship between the posterior and anterior belly of the digastric muscle?
Connected by a tendonous intersection that links to the hyoid bone by a ligament sling
What is the carotid bifurcation?
Occurs at vertebral level C3 to C4
Where the common carotid splits into the external and internal carotid artery
How can you differentiate between the internal and external carotid?
INternal - directly into cranial vault
External - more anterior, more division starting almost immediatly
What are the different devisions of the external carotid artery staring inferiorly?
(ascending) Pharnygeal artery
Superior thyroid artery
Lingual artery
Facial artery
Occipital arterty
Posterior auricular artery
Terminal branches:
Maxillary artery
Superificial temporal arterty
Anatomists sometimes like freaking out poor medical students
What are the key features of the facial artery?
Close association with the submandibular gland
Torous route
What is the role of the internal jugular vein?
Drain the cranial valut
What is found within the carotid sheat?
This is a layer of fascia surrounding the common carotid artery, the internal jugular vein and the vagus nerve
What makes up the muscular floor of the posterior triangle of the neck?
Scalenes (anterior, medius and posterior) muscles
Inferior belly of omohyoid muscle
Levator scapular muscle
splenious capitus muscle
What neurovasculature is found within the posterior triangle of the neck?
Superior trunk of the brachial plexus
Accessory nerve
FUnction of the accessory nerve
Innervates sternocladomoistoid and the trapezium
Where does the superior trunk of the brachial plexus be found?
In the posterior triangle of the neck
Between the anterior and medius scalene muscle
What is the function of the brachial plexus?
Innervates the upper limb
Describe the location of the subclavian vein and artery
Vein - pass anteriorly to the anterior scalene muscle and posterior to the sternocaldomastoid
Artery - between the anterior and middle scalene muscle
What are the two divisions of the anterior triangle of the neck?
Infrahyoid
Suprahyoid
What are the division of the suprahyoid portion of the anterior triangle?
What is the boundary between these regions?
The submandibular and The submental compartment
Seperated by the digastric muscle, with the submental being inferior to the anterior belly of digastric
What are the divisions of the infrahyoid portion of the anterior triangle?
What separates these two portions?
The carotid triangle and the muscular triangle
Separated by the omohyoid muscle
With the carotid triangle being the most superior
What is the origin an dinsertion of the sternohyoid bone?
Origin: posterior sternuocalvicular joint and manubraium
Insertion: Body of hyoid bone, medial to omohyoid
What is the function of sternohyoid?
Depress the hyoid bone after swallowing
What is the origin and insertion of the omohyoid?
Origin: superior border of the scapular medial to suprascapular notch
Insertion: lower body of the hyoid bone, just later to sternohyoid
What is the function of the omohyoid muscle?
Depress and fixes hyoid bone
What is the origin and insertion of the thyrohyoid muscle?
Origin: Oblique line on the lamina of thyroid cartilage
Insertion: Greater horn of hyoid bone
What is the origin and insertion of the sternothyroid?
Origin: Posterior surface of manubrium
Insertion: Oblique line on lamina of thyroid cartilage
Lable the following image.
- Anterior belly of digastric
- Submental triangle
- Hyoid bone
- Muscular triangle
- Superior belly of omohyoid muscle
- trapezius muscle
- Posterior triangle
- Carotid triangle
- Sternocladmastoid
- Posterior belly of digastric muscle
- Stylohyoid muscle
- Submandibular triangle
What forms the roof od the posterior triangle in the neck?
The cervical investing fascia (multiple layers, sometimes conintuous but surrounds all sides of muscle) and skin
What are the two divisions of the posterior triangle of the neck?
What separates them?
The occipital triangle (most superior)
The subclavicular triangle (most inferior)
Seperated by the omohyoid triangle
What is the contents of the subcalvicualr triangle?
THe brahcial plexus
The subclavian vein
The subclavian artery
The phrenic nerve
Describe the location of the prhenic nerve in the posterior trnaigle of the neck.
In the subclavicular triangle
Runs vertically anteriorly over the anterior scalene muscle
What is the contents of the occipital triangle?
The accessory nerve (CN XI)
Enters the triangle through the sternocladomastoid and disappear deep to the trapezius
What muscles does the accessory nerve innervate?
Sternocladomastoid
Trapezius
What are the two different parts of the sternocaldomastoid muscle?
The sternal head
The clavicular head
What is the superior point of the posterior triangle of the neck?
The superior nuchal line of the occipital protuberance
What is the function of the splenus capitus muscle
Extend the neck
Rotate and some lateral movement of the head.
What are the key branches of the cervical plexus?
C1-C4
The phrenic nerve (C3,4,5)
Anterior rami of C1,2,3 join to form ana cervicalis which innervates the infrahyoid muscles
C1 via the hypoglossal nerve - geniohyoid and thyrohyoid
What is the clinical significant of the subclavian vein?
Used for administering a central line - in acutely ill patients
May also be delivered via the jugular vein.
What is the function os sternocladomastoid?
Flexes and laterally flexes neck, rotates head
Describe the passage of the vertebral artery near the cervical vertebrae?
What is the clinical significance of this?
Traves through the transverse foramina of the C6-C1
At atlas can’t travel more superior, travels posteriorly in a groove in the posterior arch of atlas, then travels medially and superiorly into the foramen magnum
S-shape is a risk for blood clots and haemorrhage
What attaches to the transverse process of the cervical vertebrae?
Muscles including the scalene muscle and the spinous capitus muscle
What is the important content of the carotid triangle?
The common carotid artery
The internal jugular vein
The hypoglossal nerve
The vagus nerve
extra
Where is the external jugular vein located why is this important clinically?
Lacted on teh surface of the sternocaldmoiastoid
Sometimes is considered to be on the lateral border of sternocladlomastoid and includes in the posterior triangle of the neck
Important as very superficial so is easily damaged by knife crime tic.
What structures are found int eh submandibular triangle?
THe facial artery/vein
The submandibular gland
extra
What is contained within the muscular triangle of the neck?
Infrahyoid muscles
Thyroid gland
Parathyroid gland
Pharyxn
extra
Label the image
Anterior belly of diagastric
Mylohyoid muscle
Hyoid bone
Posterior belly of digastric muscle
Stylohyoid muscle
Mastoid process
Styloid process
Label the image
Mylohyoid
geniohyoid
Anterior belly of digastric muscle
Stylohyoid muscle
Posterior belly of digastric muscle
label the image
Hyoid bone
Thyroid cartilage
Omohyoid muscle
Cricoid cartilage
Sternohyoid muscle
Sternothyroid muscle
Common carotid artery
Thyrohyoid muscle
Internal jugular vein
Label the image
Hyoid bone
Superior belly of omohyoid muscle
Inferior belly of omohyoid muscle
Trapezius muscle
Subclavian triangle
Occipital triangle
Sternocleidomastoid
Label the muscles in the posterior triangle of the neck
Sternocleidomastoid
Anterior scalenes muscles
Middle scanles muscle
Clavicale
Inferior belly of omohyoid muscle
Acromion of scapular (low focus)
Trapezius muscle
Posterior scalene muscle
Levator scapulae muscle
Splenius capitis muscle
What muscle is shown in the image?
Sternothyroid muscle
What muscle is shown in the image?
Thyrohyoid
What muscle is shown in the image?
Sternohyoid
What muscle is shown in the image?
Inferior nelly of omohyoid
What muscle is shown in the image?
Superior belly of omohyoid
What muscle is shown in the image?
Trapezius
What muscle is shown in the image?
Anterior scalenes muscle
What muscle is shown in the image?
Posterior scales muscle
What muscle is shown in the image?
Middle scalene muscle
What muscle is shown in the image?
Levator scapulae
What muscle is found in the image?
Splenius capitis
What features of the hyoid bone is highlighted?
Tubercule of hyoid bone
What features is highlighted in pink?
Posterior arch of atals
What features is highlighted in pink?
Anterior arch of atlas
Identify the green and red holes
Green - vertebral foramen
Red holes - transverse foramen
What features is highlighted in pink? What features is it associated with?
The lateral mass of atlas
Associated with the superior and inferior articular process of Atalas
Identify A B and C
A anterior articular facet of dens
B dens
C posterior articular facet of dens
Transverse ligament of Atlas
