Week 1- general anatomy and scalp Flashcards Preview

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Flashcards in Week 1- general anatomy and scalp Deck (85):

Where does the neck extend from and to?

  • From lower msrgin of mandible to suprasternal notch of manubrium and upper border of clavicle 


Label this m8 

  1. Body of hyoid bone 
  2. Greater horn of hyoid bone 
  3. laryngeal prominence 
  4. Thyroid cartilage 
  5. Cricoid cartilage 
  6. Lobe of thyroid gland 
  7. First tracheal ring 
  8. Isthmus of thyroid gland 


What is the adam's apple?

Thyroid cartilage 


What do the thyroid and cricoid cartilages do?

Protect the underlying larynx 


There are many muscles in the neck. What are the main three? Which are involved in forming anatomical boundaries in the neck?

  • Main three: 
    • Platysma 
    • Sternocleidomastoid 
    • Trapezius 
  • Sternocleidomastoid and trapezius are involved in forming boundaries 


Where does platysma lie?

  • Anterolateral neck 
  • It is v superficial and lies within the superficial fascia 
  • It overlies the sternocleidomastoid 


What is the action of platysma?

  • Draws corners of the mouth down 
  • Draws skin of the neck superiorly if teeth are clenched 


What is the nerve supply of platysma?

  • Facial nerve (CN VII) 


Where does the sternocleidomastoid lie?

  • From mastoid process to clavicle and sternum (has 2 heads)
  • It is deep to platysma 


What is the action of sternocleidomastoid?

  • If unilateral contraction:
    • Lateral flexion of neck (ear towards shoulder, rotating chin superiorly)
    • Basically head tilt from side to side 
  • If bilateral contraction:
    • Flexion at neck, extension at atlanto-occipital joint 
    • Basically nodding motion 


What is the nerve supply of sternocleidomastoid?

  • Accessory nerve (CN XI)


Where does trapezius lie?

  • From back of skull, nuchal ligament and spinous process of vertebrae to lateral 1/3rd of clavicle, acromion and spine of scapula 


What is the action of trapezius?

  • Elevates and rotates scapulae 
  • Basically shoulder shrug 


When is the superior border of trapezius seen?

  • When the shoulders are shrugged against resistance 


What is the nerve supply of trapezius?

  • Accessory nerve (CN XI) 


What are the borders of the anterior triangle of the neck?

  • Superior border:
    • Inferior margin of mandible 
  • Posterior border:
    • Anterior margin of sternocleidomastoid 
  • Anterior border:
    • Midline of neck 


What are the borders of the posterior triangle of the neck?

  • Inferior border:
    • Clavicle 
  • Posterior border: Anterior margin of trapezius 
  • Anterior border: posterior margin of sternocleidomastoid 


Which structures pass through the anterior and posterior triangles of the neck?

  • Anterior triangle:
    • Structures running between the head and thorax 
  • Posterior triangle:
    • Structures running between thorax/neck and upper limb 


What are the fascial planes of the neck from superficial to deep?

  • Superficial cervical fascia
  • Deep layers:
    • Investing layer 
    • Pretracheal layer 
    • Prevertebral 


What does the superficial cervical fascia contain?

  • Fat 
  • Platysma 
  • Cutaneous nerve 
  • Lymph nodes
  • Superficial blood vessels


Where is the investing layer of fascia in the neck?

  • It surrounds the neck like a collar 
  • Superiorly it is attached to:
    • Lower border of mandible, mastiod process, superior nuchal line, external occipital protuberance, spinous processes of the vertebrae and ligamentum nuchae 
  • Inferiorly is is attached to: 
    • Upper border of manubrium, upper surface of clavicle, acromion, spine of scapula 


What does the investing layer split to include?

  • Sternocleidomastoid, trapezius, submandibular annd parotid glands


Where is the pretracheal layer? 

  • It is thin and limited to the anterior part of the neck 
  • Superiorly is is attached to:
    • Hyoid bone 
  • Inferiorly it:
    • extends into the thorax and blends with fibrous pericardium 


What are the two parts of the pretracheal layer and what do they contain?

  • Muscular 
    • Contains infrahyoid muscles 
  • Visceral
    • Encloses thyroid gland, trachea and oesophagus


What is the buccopharyngeal fascia?

  • It is part of the pretracheal fascia which is close to the oesophagus and pharynx 


Where is the prevertebral fascial layer?

  • Forms a sheath for vertebral column and muscles associated with it 
  • Extends from base of cranium to 3rd thoracic vertebrae 
  • Extends laterally as the axillary sheath that surrounds the axillary vessels and brachial plexus 


How can the pretracheal fascia be used when localising pathology to the thyroid gland?

  • Pretracheal fascia surrounds the thyroid gland and is also attached to the hyoid bone
  • The hyoid bone and larynx move upwards when swallowing and therefore so does the thyroid gland (and any associated pathology)
  • We can ask a patient to swallow and if the lump moves this can help to localise the pathology to the thyroid gland


Why can goitres sometimes present with breathlessness, stridor and facial oedema?

  • Enlarged thyroid cna sometimes extend retrosternally becuase the lower limit of the pretracheal fascia extends into the thorax 
  • This can compress other structures which run through the base of the neck e.g. trachea and venous blood vessels therefore causing these symptoms 


Wtf even is the carotid sheath?

  • The deep fascial layers (investing, pretracheal and prevertebral) create a compartment for neurovascular structures to run between the head and thorax. This is known as the carotid sheath. 


Where does the carotid sheath run? What does it contain?

  • Runs from base of the cranium through the root of the neck to the arch of aorta 
  • Contains: 
    • Carotid artery 
    • Internal jugular vein 
    • Vagus nerve 


Layers of deep cervical fascia form natural cleavage planes. What does this allow?

  • Structures to pass over each other with ease 
  • Easy separation of tissues in surgery 
  • Determines the direction and extent of spread of infection in the neck 


Where is the retropharyngeal space? What is the space useful for? Until what ages are lymph nodes found here?

  • Between the prevertebral fasica and fascia surrounding the pharynx (buccopharyngeal fascia) 
  • It is useful in allowing the pharynx to move freely on the vertebral column and expand when swallowing 
  • Lymph nodes till age of 3-4  


Who are infections of the retropharyngeal space most common in? What may they present as?

  • Most common in under 5s 
  • May develop into an abscess and present as:
    • Visible bulge of oropharynx 
    • Sore throat
    • Difficulty swallowing 
    • Stridor 
    • Neck stiffness 
    • High temperature 


How can mediastinitis be caused?

  • Infection in the retropharyngeal and pre-tracheal spaces can spread inferiorly to cause mediastinitis as the spaces extend into the mediastinum 


What can increase risk of transfer of bacteria into the pre-tracheal space?

  • Inserting surgical airways e.g. tracheostomy


What is the difference between the face and the scalp?

  • Face is below the eyebrows
  • Scalp is above the eyebrows


What are the main muscles in the head?

  • Muscles of facial expression 
  • Muscles of mastication 
  • Others:
    • Muscles of the cheek (buccinators)
    • Occipitofrontalis 


  • Where are muscles of facial expression found? What are they innervated by? 

  • They surround orifices of the mouth, eyes and nose and act as sphincters and dilators 
  • They are inverated by cranial nerve VII (facial)


Gives 2 examples of dilator muscles of facial expression 

  • Zygomaticus and risorius 
  • They act by drawing on the angles of your mouth, allowing you to smile and show your teeth 


What is the main action of the muscles of mastication? What are they innervated by?

  • They act to open and close the jaw 
  • Innervated by: cranial nerve V (trigeminal) 


What is another name for cranial nerve VII? What does it supply?

  • The facial nerve
  • Supplies:
    • Superficial muscle of neck and chin (platysma)
    • Muscles of facial expression 
    • Buccinators 
    • Muscles of the ear 
    • Occipitofrontalis 


What are the 5 key branches of the facial nerve (CN VII)? What do they each supply?

  • Temporal 
    • Frontalis, orbicularis oculi, corrugator supercilli
  • Zygomatic 
    • Orbicularis oculi 
  • Buccal 
    • Orbicularis oris, buccinator and zygomaticus 
  • Marginal mandibular 
    • mentalis 
  • Cervical 
    • Platysma 


The facial nerve has motor innervation to the muscles of facial expression. Whar else does it do tho?

  • Special sensory to tongue-taste
  • Parasympathetic to salivary and lacrimal glands


What does the facial nerve (CN VII) run through?

  • The parotid gland 
  • So pathology there can affect it 
  • The facial nerve and branches are superficial and are vulnerable to damage in injuries to the face and in disease/surgery of the parotid gland 

As it runs through it branches into 5 branches and depending on which of these branches are affected there will be different signs


What does injury to the facial nerve (CN VII) cause?

  • weakness of the muscles of facial expression on the ipsilateral side (facial droop)
  • Most common non-traumatic cause of facial paralysis is inflammation of facial nerve near its exit from cranium at stylomastoid foramen (Bell's palsy)
    • Inflammation causes oedema and compression of the nerve in intracranial facial canal 


What are the three key branches of cranial nerve V (trigeminal nerve)?

  • Opthalmic 
  • Maxillary 
  • Mandibular 
    • Motor innervation to muscles of mastication 
  • It is the main sensory nerve of the face and scalp



The common carotid artery is the main blood supply to the head and neck via its terminal branches. What are these?

  • Internal carotid
    • continues up in carotid sheath to supply the brain 
  • External carotid
    • Facial artery branch leaves the sheath to supply the face 


What is the main venous drainage of the head and neck? Which other vein is involved?

  • Main vein= Internal jugular vein 
    • Receives drainage from facial vein 
  • External jugular vein also receives drainage from scalp and face 


Why can major blood vessels (common carotid arteries and jugular veins) and nerves be damaged in penetrating wounds e.g. stab injuries of the neck?

  • They lack bony protection 


Why do scalp wounds often bleed heavily?

  • Blood vessels supplying the scalp arise from internal and external carotid arteries and anastamose to provide a rich blood supply 


Where can the pulse of the facial artery be palpated?

The facial artery winds round the inferior border of the mandible and it can be palpated here 


Why must both facial arteries be compressed if there is laceration of one?

  • As it has many anastamoses with other arteries of the face and so if there is laceration of the artery on one side of the face, both must be compressed to stop bleeding 



Label this yeh 

  1. Trachea 
  2. Oesophagus 
  3. Sternocleidomastoid
  4. Recurrent laryngeal nerve 
  5. common carotid artery 
  6. Carotid sheath 
  7. Internal jugular vein 
  8. Vagus nerve 
  9. Thyroid gland 
  10. Prevertebral layer 
  11. Investing layer 


Label it 


bit more labelling fun


Label the branches of the facial nerve 


Label label label 

  1. Opthalmic branch 
  2. Maxillary branch 
  3. Mandibular branch 


How do you test the facial nerve?

  • Forehead creasing by raising the eyebrows
  • Keep eyes shut against resistance
  • Puff out cheeks 
  • Smile 


How do you test the trigeminal nerve?

  • Test sensory portion by lightly touching the face with cotton wool and then a pin around the jaw line, on the cheek and on the forehead 
  • The nerves are paired so you must check both sides 
  • To test the motor function ask the patient to clench their jaw 


What is forehead sparing?

  • When the forehead can still move in upper neurone lesions but not in lower neurone lesions
  • Bells palsy is a lower motor neurone lesion 
    • It affects the ipsilateral face 
  • Stroke is an upper motor neurone lesion 
    • It affects the contralateral face 


What is the action and nerve supply of the following muscles?

  • Orbicularis oculi 
  • Levator palpebrae superioris 
  • Orbicularis oris 
  • Buccinator 

  • Orbicularis oculi 
    • Closes the eyelids
    • Facial nerve (temporal and zygomatic)
  • Levator palpebrae superioris 
    • Elevates superior eyelid 
    • Oculomotor nerve 
  • Orbicularis oris
    • Compression and protrusion of lips 
    • Facial nerve (buccal branches)
  • Buccinator
    • Builds muscular substructure of cheeks and controls food synergistically with the tongue and draws mouth unilaterally
    • Facial nerve (buccal) 


What is the action and nerve supply of the following muscles?

  • Dilator muscles e.g. zygomaticus 
  • Pterygoids (lateral and medial)
  • Masseter 
  • Temporalis 

  • Dilator muscles 
    • Elevate mouth and draw the angle of mouth laterally
    • Buccal and zygomatic  branches of facial nerve 
  • Pterygoids 
    • Protraction and elevation of mandible and aids in mastication 
    • Mandibular devision of trigeminal nerve 
  • Masseter
    • Elevation, adduction and protrusion of the mandible 
    • Mandibular division of trigeminal nerve 
  • Temporalis 
    • Elevates mandible, retracts mandible and aids mastication
    • Deep temporal nerve (branch of facial)


Which muscle forms the muscle of the scalp? What is its action and innervation?

  • Occipitofrontalis 
    • frontalis and occipitalis 
  • It raises the eyebrows and crinkles forehead
  • Innervated by temporal branches of facial nerve


Label these branches of the external carotid artery 


more labelling pls 

  1. Mandibular angle 
  2. Inferior margin of mandible 
  3. Trapezius 
  4. Omohyoid, inferior belly 
  5. Clavicular head of sternocleidomastoid 
  6. Sternal head of sternocleidomastoid 
  7. Jugular notch 
  8. Clavicle 
  9. Thyroid cartilage 


How many layers does the scalp have?



What makes up the scalp proper?

  • The first 3 layers (skin, connective tisse and epicranial aponeurosis)
  • They are connected intimately and move together e.g. when wrinkling the forehead 


What are the 5 layers of the scalp? 

(use the word scalp to help remember)

  • Skin 
    • Thin, except in occipital region 
    • Contains many sweat and sebaceous glands and hair follicles 
    • Has abundant blood supply 
  • Connective tissue 
    • Thick, dense and richly vascularised
    • Supplied by cutaneous nerves 
  • Epicranial aponeurosis 
  • Loose areolar tissue 
    • sponge like layer with potential spaces which can distend with fluid due to injury/infection 
  • Pericranium 
    • External periosteum of the neurocranium 


Whic muscle bellies attach at the epicranial aponeurosis (3rd layer of scalp)?

  • Occiptofrontalis and muscles from the temporal bones (temporoparietalis and superior auricular muscles) 


What are all parts of the epicranius supplied by? 

  • All parts (muscles and aponeursis) supplied by the facial nerve 


Describe the innervation of the scalp

  • Anterior to the auricle of the external ears it is innervated through branches of all 3 divisions of the trigeminal nerve 
  • Posteiror to the auricles supply is from spinal cutaneous nerve (C2 and C3) 


Why is bleeding from scalp woounds profuse?

  • Rich blood supply with arteries running in 2nd scalp layer (connective tissue) and anastamosing 
  • The walls of the arteries are firmly attached to dense connctive tissue in which they are embedded, this limits the ability to constrict when cut so bleeding from scalp wounds is profuse 


Describe the arterial supply to the scalp

  • External carotid artery via:
    • Occipital, posterior auricular and superficial temporal arteries 
  • Internal carotid artery via:
    • supratrochlear and supra-orbital arteries 


What is the main blood supply to the neurocranium?

  • Middle meningeal artery 


Describe the venous drainage of the scalp

  • Superficial parts are drained by accompanying veins of the scalp arteries 
  • Deep parts in the temporal region drained through deep temporal veins which are tributaries of pterygoid venous plexus 
  • Occipital region drained by occipital veins 


Why do superficial scalp wounds not gape wheras deep ones in the coronal plane do?

  • Superficial 
    • Do not gape as epicranial aponeurosis holds the margins of the wound together
  • Deep 
    • Gapes widely as the pull of the frontal and occipital bellie of the occipitofrontalis are in opposite directions 



Which scalp layer is a 'danger' zone for infection

  • Layer 4 (loose areolar tissue) 
  • Pus and blood can spread easily within this layer 


Where can infection of the scalp spread to?

  • Cranial cavity through emissary veins and reach intracranial structures e.g. meninges 
  • Eyelids and root of nose as occipitofrontalis inserts into the skin and subcutaneous tissue but does not attach to bone 


What is ecchymosis?

  • Purple patches caused by extravasation of blood into the subcutaneous tissue and skin of the eyelids and surrounding regions
  • (Black eyes, can be caused by injury to the scalp/forehead)


Where can infection of the scalp NOT spread to?

  • The neck as the occipital bellies of occipitofrontalis attach t the occipital bone and mastoid parts of the temporal bones
  • Laterally beyond the zygomatic arches because the epicranial aponeurosis is continous with the temporal fasica that attaches to these arches


Where does the carotid sheath extend to and from?

  • From the base of the skull to the aortic arch 


If you ask someone to squeeze their eyes tightly together and try and prevent you from trying to prise them open, what muscle are they using?

  • Orbital part of orbicularis oculi