Anatomy nervous system Flashcards
Order of nerves from brachial plexus
Roots, trunks, divisions, cords, branches
Which plexus does subcostal originate from
Lumbar
Saphenous nerve is a branch of
Femoral
Course of saphneous nerve
Runs in adductor canal with femoral artery
Doesn’t run through adductor hiatus
Crosses femoral artery to lie medially and passes between sartorial and gracilis, passing through deep fascia to run inferiorly with great saphenous vein
Branches of facial nerve extracranial
Branches to posterior auricular, stylohyoid, and to post digastric
Then enters parotid
Temporal, zygomatic, buccal, marginal mandibular, cervical
Nerve supply of pinna and external acoustic meatus
Greater auricular C2
Lesser occipital
Auriculotemporal (V3)
EAM- AT ant, vagus, PA from facial
Nerve damaged for foot drop
Common peroneal
Klumpke vs erb palsy anatomically
Erb- upper trunk C5,C6
Klumpke- lower C8, T1
Nerve roots of medial, lateral and posterior cord
Lateral- C5-C7
Posterior - C5-T1
Medial - C8, T1
Which muscles foes medial plantar supply
First lumbrical
FDB
FHB
Abductor hallicus
LAFF
Sensory supply of forearm
Lateral cutaneous nerve of forearm - from muscocutaenous
Medial cutaneous- brachial plexus
Posterior -radial nerve
Course of superficial radial nerve
At the cubital fossa as the radial nerve divides into superficial and deep branches at the level of the lateral epicondyle
Travels in a plane between the brachioradialis and pronator teres muscles.
About 7cm proximal to the wrist, it pierces the deep fascia of the forearm to wind around the radius, pass over the anatomical snuffbox
Provides sensory function to the dorsal of hand
Sensory function of radial nerve
Lower lateral arm
Posterior arm
Posterior forearm
Dorsal of hand - by superficial branch
Branches of radial nerve
Superficial
Deep- which continues at posterior interosseous after passing through supinator
Nerve roots assigned to each movement in upper limb
C5- elbow flexion
C6- wrist extension
C7- elbow extension
C8- flexion of middle distal phlanx
T1- little finger abduction
Symptoms of facial nerve palsy proximal to internal acoustic meatus
Hyperacousis - stapedius
Decreased salvation - nerves to sublingual and submandibular
Loss of taste in ant 2/3- chorda tympani
Unilateral face paralysis
Nerve root of sciatic nerve
L4,5 S1-3
Scatic nerve pathway out of pelvis
Greater sciatic foreamen
Under piriformis
Over top of obturator externes and quadratus femoris
On top of adductor magnus
Dermatomes of leg
L1- hip and groin
L2- Anterior thigh
L3- knee
L4- medial lower leg (floor)
L5- lateral
S1-little toe
S2- post knee
S3,4,5 smaller circles in central buttock
Symptoms of different areas radial nerve damage occurs
Above elbow- reduced sensation in forearm
In spiral groove- tricep reflex maintained, but brachioradialis decreased
Axillary- tricep reflex lost, decreased sensation of triceps
Below- sensation in tact in forearm
Wrist- isolated sensory changes in dorsum of hand
Vagus nerve relations
Passes in between internal jugular and common carotid in sheath
Right R passes under subclavian
Left R passes under aortic arch from anterior to posterior lateral to ligament arteriosum
Where does the radial nerve pass through triceps
Between medial and long head of triceps
Ulnar nerve roots
C8, T1
Radial nerve roots
C5-T1
Median nerve roots
C5-T1
Ulnar nerve pathway
Travels down between axillary vein and artery to lies posterior to carocobrachialis
Medial to brachial artery
In forearm passes between 2 heads of FDP
Roots of cervical plexus
C1-4
Branches of cervical plexus
Nerves to genio and thyrohyoid- C1
Greater auricular -C2,3- sensation to external ear and parotid
Lesser occipital - C2- posterior scalp sensory
Transverse cervical - C2 and C3. It curves around the posterior aspect of the sternocleidomastoid, and supplies sensation to the anterior neck
Ansa cervicalis - loop of nerves, formed by nerve roots C1-C3. It gives off four muscular branches:
Superior belly of the omohyoid muscle
Inferior belly of omohyoid muscle
Sternohyoid
Sternothyroid
Phrenic - C3,4,5- diaphragm
Supraclavicular nerves- C3,4 - sensory to supraclavicular fossa
Where to do a cervical nerve block
Midway up the posterior border of the sternocleidomastoid
As this is where lots of cutaneous branches emerge
Median nerve course
Lies lateral
Cross over to medial at midpoint of humerus
Separated from ulnar nerve in forearm by pronator teres
Gives off anterior interosseous
Supplying PQ, FPL, FDP
Phrenic nerve course
Arrises from anterior C3,4,5
Passing between scalenus medius and anterior
Travel laterally to vagus then anterior
Right courses inferiorly lateral to SVC onto fibrous pericardium overlying right atrium
Travels anterior to root of lung then passes through with IVC at canal orifice at T8
Left- crosses anterior arch of aorta (vagus is posterior)
Courses inferiorly anterior to left pulmonary artery
Crosses left lung root anteriorly
Pierces central tendon of diaphragm
Where each cervical ganglion lie
Superior C2-3
Middle C6
Inferior C7- often infusing with thoracic- called stellate
What cranial nerves receive input from superior cervical ganglion
II, III IV, VI and IX.
For sympathetic input
Action of trochlear nerve
Down and in
Nerves passing through tendinous ring
Superior division of the oculomotor nerve (CNIII)
Nasociliary nerve (branch of ophthalmic nerve)
Inferior division of the oculomotor nerve (CNIII)
Abducens
Where does the ciliary ganglion lie and what goes through it
Apex of orbit, lateral to optic nerve
Sensory from nasociliary
Post Sympathetic from internal carotid
Pre para from Erdinger Westphal
What is the carotid plexus
Sympathetic fibres from cervical ganglion
Where does vagus originate
Medulla
How do vagus nerves enters abdomen in relation
At T10
Left anterior to oesophagus
Right posterior
Branches of vagus
Pharyngeal
Superior laryngeal- splits into internal and external
Recurrent laryngeal
Cardiac
Damage to stellate ganglion can lead to
Horners syndrome
Cremastatic innervation
Gential of genitofemoral
L1-2
Which nerve causes Meralgia parasthesia
Lateral cutaneous nerve of thigh
What may distinguish between a peripheral nerve lesions vs nerve root
Whether it has a motor/sensory deficit
Symptoms of ilioinguinal injury
Parasthesia over pubis and anterior scrotum
Motons neuroma effects which nerve
Common plantar nerve
Origination of CN
CN3-4 midbrain (3 at junction)
5-8 Pons originate (6-8 junction between pons and medulla)
9-12 Medulla (11 originate in spinal cord)
Which cranial nerves have parasympathetic innervation
3- sphincter pupillae, cilliary
7- lacrimal, submandibular, sublingual
9- parotid
10- abdo viscera up until colic flexure
Is wrist extension possible if damage to posterior interosseous muscle
Yes
Since main branch of radial supplies EDRL
Which 2 muscles does radial nerve pass between when entering forearm
Brachial and brachioradialis
Which structure separates discs from spinal cord
Posterior longitudinal ligament
What controls circadian rhythm in hypothalamus
Suprachiasmic nucleus
What controls temperature in hypothalamus
Pre optic, anterior and posterior nuclei
Sphenoid sinus and pituitary relation
Pituitary superior
blood supply of pituitary
Share venous
Different arterial
ANt- superior hypophyseal artery (a branch of the internal carotid artery). This vessel first forms a capillary network around the hypothalamus
Post- inferior hypophyseal
Areas of pituitary
Pars anterior – the largest part, responsible for hormone secretion.
Pars intermedia – a thin epithelial layer that separates the pars anterior from the posterior lobe.
Pars tuberalis – an upwards extension of the pars anterior that surrounds the anterolateral aspect of the infundibulum.
Pelvic splanchnic roots
S2-4
Where does the vagus supply up to in the gut and what supplies beyond
Until the midgut - until splenic flexure
Beyond is pelvic splanchnic
Symp and para innervation of pupil
Sym- superior cervical T1
Para- CN 3
Which ventricle is bound laterally by thalamuc
Third
What is between optic chimsm and pituitary
Diaphragma sella
Fold of dura covering - between optic chasm
Relation of stellate ganglion
Anterior to the neck of the first rib
Stellate fuses with frost thoracic
Stroke effecting medial pons symptoms
Contains 6,7th CN
Also 5th and 8th
Inability to abduct, facial palsy mainly
Also cause hemisensory loss
Horners
What area does the middle meningeal artery originate
Infratemporal from maxillary
Sympathetic ganglion to abdo
Greater- T5-9- coeliac- foregut
Lesser- T10-11- SM- midgut
Least-T12- renal
Lumbar splanchnic- IML1-2 hindgut
Lateral geniculate nucleus of thalamus is involved in
Vision
Where taste is perceived in brain
Solitary nucleus
Where is the inferior sagittal sinus located
Enclosed in posterior half of free margin of flax cerebri
Has no valves
Anterior vs middle cerebral artery symptoms
Anterior - Leg>arm
Middle - Arm, face >leg
Largest , most commonly affected
Branches of basilar arteries
AICA
Pontine arteries
Superior cerebellar
PCA
Wernicke and Broca location and function
Wernicke- comprehension, temporal lobe
Broca- language production, frontal lobe of dominant
Midbrain, pons, medulla other names
Midbrain- mesencephalon
Pons- meten
Medulla- myelen
What connects hypothalamus and pituitary
Infundibiulum
Posterior hypothalamus- neurosecretory cells which run down to poster pituitary - called median eminence
Anterior- hypophyseal portal vessels connects
Nucleus in hypothalamus controlling satiety
Verntromedial
Where is ADH synthesised
Supraotpic nuclei of hypothalamus
Sympathectomy levels and what is avoided
T2-3
Avoid T1 for Horners
Stroke to thalamus symtpoms
Contraleteral hemianaethesia
Hyperaesthesia
Mood swings
Cause of macular sparing homonymous hemianopia
Occipital stroke
If occipital pole in tact through dual supply of MCA
Pedicles vs laminae
Pedicles- body and transverse
Lamina- transverse and spinous
Intrafusal vs Extrafusal muscle fibres
Intrafusal- detect change of length
Extrafusal- contraction- a motor
What can narrow spinal cord posteirorly
Ligamentum flavus hypertrophy
Cause of locked in syndrome
Basillar artery occlusion
Which vertebra do the facet joints lie parallel to frontal plane
Cervical
Spinal nerves of sacral plexus
L4-S4
Problem in spondylosis and its location
Pars Artciularis
Part of a vertebra located between the inferior and superior articular processes of the facet join
Most common spondylosis vertebrae
L5
Roots of femoral
L2-4
Guillan Barre features
Ascending paralysis
Autonomic neuropathy
Arrythmia
Acute dymelingation
Location of venous plexus of spine
Epidural space
Can extend knee but not flex- level of damage
L5
Myotomes of leg
Hip flexion- L1/2
Knee extension-L3
Dorsiflexion-L5
Great toe- L5
Ankle plantar- S1
