Week 3: Root of Neck, ANS, Scalp & Cranial Cavity Flashcards
boundaries of root of neck are
anterior - Top of manubrium & superior border of clavicle
posterior - body of T1 & superior margin of scapula to coracoid process
lateral - : First pair of ribs & costal cartilages
inferior- Superior thoracic aperture (thoracic inlet) & axillary inlets
The major nerve structures which pass from the neck through the axillary inlets are
brachial plexus
brachial plexus formed of
the anterior rami of five spinal nerves – C5 to C8 and T1
what is the cervical pleura?
it is the region of the parietal pleura extending through the superior thoracic aperture to coat the apex of the lungs.
It is a continuation of the costal and mediastinal parietal pleura. It is dome-shaped
what is the cervical pleura is reinforced by?
fibrous extension of endothoracic fascia, which forms the suprapleural membrane/ Sibson’s fascia.
This attaches to internal border of first rib and the transverse process of the vertebra prominens, C7.
3 branches of the aortic arch
brachiocephalic artery
L common carotid
L subclavian artery
what are the 3 parts of the subclavian artery?
1st part: prescalene - Medial to anterior scalene muscle
2nd part - postscalene: Posterior to anterior scalene muscle
3rd part - retroscalene : Lateral to anterior scalene muscle. Lies anterior to trunks of brachial plexus; also longest & most superficial part of the artery
branches of subclavian artery
vertebral artery
thyrocervical trunk
internal thoracic artery
costocervical trunk
dorsal scapular
prescalene branches of subclavian artery
Vertebral artery
thyrocervical trunk
internal thoracic artery
postscalene branches of subclavian artery
costocervical trunk
retroscalene branches of subclavian artery
dorsal scapular artery
subclavian vein is a continuation of which vein?
axillary vein
what does the subclavian vein join with to form the brachiocephalic vein
internal jugular
what are the (anterior) prevertebral muscles?
Longus colli
Longus capitis
Rectus capitis anterior
Anterior scalene
what are the (posterior) prevertebral muscles?
Rectus capitis lateralis
Splenius capitis
Levator scapulae
Middle & posterior scalenes
what is the central nervous system
composed of brain and spinal cord
what is the peripheral nervous system
spinal nerves & cranial nerves
what is the autonomic nervous system
controls involuntary responses part of PNS
what is the sympathetic and parasympathetic nervous system
part of ANS:
fight or flight
rest and digest
what is Horner’s syndrome
Damage to cervical sympathetic trunk resulting in absence of sympathetically stimulated functions on ipsilateral side of head
cervical part of the sympathetic trunk includes
superior cervical ganglion
middle cervical ganglion
inferior cervical ganglion
cervical ganglia
superior cervical ganglion branches v
ICA & ECA (forming plexuses)
Cervical spinal nerves (C1-C4, cervical plexus)
Pharynx
Superior cardiac nerves
the middle cervical ganglion supply branches via
Cervical spinal nerves (C5, C6)
Middle cardiac nerves
the inferior cervical ganglion branches
Vertebral artery (forming a plexus)
Cervical spinal nerves (C7-T1; C7 & C8 to brachial plexus)
inferior cardiac nerves
cervical ganglia regulate sympathetic innervation of
Eyes (pupil dilation), eyelids, lacrimal glands, carotid body, salivary glands, sweat glands
clinical features of Horner’s syndrome
Constriction of pupil (miosis)
Drooping of superior eyelid (ptosis)
Vasodilation & absence of sweating on face/neck (flushed face & anhydrosis)
what are the parasympathetic cranial ganglia
ciliary ganglion
pterygopalatine ganglion
submandibular ganglion
otic ganglion
where are the ciliary ganglion located?
Between the optic nerve and the lateral rectus muscle
where are the pterygopalatine ganglionlocated
Within the pterygopalatine fossa
where are the submandibular ganglion located
Suspended from the lingual nerve, close to submandibular gland
where are the otic ganglionlocated
below the foramen ovale in the infratemporal fossa a
what does the scalp consist of
skin & subcutaneous tissue from the superior nuchal line of the occipital bone to the supraorbital margins of the frontal bone
how does the scalp extend laterally
over the temporal fascia to the zygomatic arch
what is the face
the anterior aspect of the head from forehead to chin & from one ear to the other
what are the layers of the scalp
Skin
(Dense) Connective Tissue
Epicranial Aponeurosis
Loose Connective Tissue
Pericranium
what is the (dense) connective tissue of the scalp
Subcutaneous layer richly vascularised & with cutaneous nerves
what is the epicranial aponeuorisis layer of the scalp
Tendon & muscle of occipitofrontalis
what is the loose connective tissue layer of the scalp
that allows free movement of outer layers over underlying calvaria
what is the peroicranium layer of the scalp
External periosteum of skull
what is the cutaneous nerve supply to the scalp
Cutaneous/sensory innervation is supplied via
CN V (V1, V2, V3)
Cervical nerves from C2 & C3
what is the cutaneous nerve supply to the scalp
CNV1
- Supratrochlear , Supraorbital
CNV2
- Zygomaticotemporal
CNV3
- Auriculotemporal
C2
- Greater occipital nerve ,Lesser occipital nerve
C2-3
-Great auricular nerve
C3
-Third occipital nerve
CN V1 branches
Supraorbital
Supratrochlear
Infratrochlear
External nasal
Lacrimal
CN V2 branches
Zygomaticotemporal
Zygomaticofacial
Infra-orbital
CN V3 main branches
Auriculotemporal
Buccal
Mental
skin over the angle of the mandible is innervated by which nerve(s)
the cervical plexus with the great auricular nerve (C2 & C3)
Arterial supply to the scalp is from
anterior scalp = the internal carotid arteries
lateral & posterior scalp = external carotid arteries
branches of the ICA that supply anterior scalp
Supraorbital
Supratrochlear
branches of the ECA that supply the lateral and posterior scalp
Superficial temporal
Posterior auricular
Occipital
venous drainage of the scalp
external jugular vein
(except occipital vein that drains to the internal jugular vein)
what are the 2 means of lymphatic drainage of the scalp
Posterior: Mastoid & occipital nodes drain to deep cervical nodes
Anterior: Pre-auricular & parotid nodes
what are the 3 cranial fossae within the skull
anterior, middle, posterior
what are the boundaries of the anterior cranial fossa
anterior: cribriform plate of ethmoid bone, orbital plate of frontal bone, lesser wings and body of sphenoid bone.
posterior: lesser wings of sphenoid bone.
what are the boundaries of the middle cranial fossa
anterior: posterior margins of the lesser wings of the sphenoid bone; anterior clinoid processes; anterior margin of the chiasmatic groove.
posterior: anterior surface of petrous temporal bones; dorsum sellae.
what separates the middle and posterior cranial fossa
The petrous temporal bones
what does the posterior cranial fossa contain
cerebellum & brainstem
what are the boundaries of the posterior cranial fossa
Anteriorly it extends to the apex of the petrous temporal.
Posteriorly it is enclosed by the occipital bone.
Laterally portions of the squamous temporal and mastoid part of the temporal bone form its walls.
what are the cranial meninges
pia mater
dura mater
arachnoid mater
what the the layers of the dura mater
Periosteal Layer
Attached to bone
Meningeal Layer
In contact with arachnoid mater
where do 2 layers of dura mater separate at
Venous sinuses
Dural folds
features of the arachnoid mater
Lines the dura mater
Trabeculae project from internal surface, across the subarachnoid space, and are continuous with the pia mater
what is the subarachnoid space
Fluid filled space
Contains cerebrospinal fluid (CSF) and blood vessels
in between arachnoid and pia mater
what is the pia mater
Thin membrane attached to surface of brain
what importance do the dura mater folds have
Limit the movement of the brain within the cavity
what is the blood supply to the dura mater
by meningeal arteries