Block 12 key things to learn

Question 1

What are the spinal levels of reflexes?

Answer 1

Biceps C5/ C6
Triceps C7
Patella L4
Achilles S1

Question 2

What is the key difference between central and peripheral sensitisation?

Answer 2

Peripheral is linked with inflammatory mediators prostaglandins etc causing a reduced threshold for neuronal activation due to hyper excitability of peripheral nociceptors

Central is linked with increased glutamate and substance P leading to transcriptional changes and a reduced pain threshold

Question 3

What are the fibular collateral ligaments of ankle and what happens when have inversion injury?

Answer 3

Anterior talofibular
Posterior talofibular
Calcaneofibular
So strong that more likely to break fibular than these

Question 4

What are the medial collateral ligaments of ankle and what happens on eversion injury?

Answer 4

Anterior tibiotalar
Posterior tibitalar
Tibiocalcaneal
Tibionavicular
Get trimalleolar fracture due to injury to ligaments causing break of medial malleolus, tibia and lateral malleolus of fibular

Question 5

Where does neural control of pupil come from?

Answer 5

Sympathetic (widen pupil) from superior cervical ganglion via oculomotor nerve

Parasympathetic from oculomotor nerve to ciliary ganglion to sclera muscle

Question 6

How does the eye focus on close up and far away objects?

Answer 6

Distance- lens thin and suspensory ligament tense, ciliary muscles relaxed

Close- lend round, ciliary muscle tense, suspensory ligament relaxed

Question 7

What visual loss would you get with an issue in different parts of visual system?

Answer 7

Optic nerve lesion- anopia of whichever eye

Optic chiasm- no crossing of visual fields- bitemporal hemianopia- can only see middle area not either side

Lateral geniculate nucleus- lose opposite side visual field, e.g. if in left nucleus then will get a right homonymous hemianopia

Optic tract- if just lose 1 fibre then you will only lose a quarter of your visual field- e.g. if on a fibre on the left you would get a right homonymous superquadrantopia

Occipital lobe- would lose the opposite sides visual field, same as if LGN lesion

Question 8

What are the stages of anaesethscia?

Answer 8

1- induction:
immediately after administration until loss of consciousness. Big pupils react to light, irregular reps and heart rate, normal bp

2-Excitement:
After loss of consciousness
Excited and delirious activity, uncontrolled movements
Irregular resps and heart rate, big pupils react to light, high bp

3-surgical anaesthesia-
Pupils small and don’t react to light
Regular low resps and heart rate
Normal bp, skeletal muscle relaxation

4- overdose
severe brainstem and medullary depression
cardiovascular collapse
big fixed pupils
weak resps, weak thready pulse, low bp

Question 9

What is wallenburg syndrome?

Answer 9

issue with artery supplying medulla- posterior cerebral artery, causes issues with cranial nerves 9-12

Question 10

What happens if have oculomotor nerve lesion?

Answer 10

Eye points down and out, dilated pupil due to lack of parasympathetic innervation, partial ptosis

Question 11

What is seen in horners syndrome

Answer 11

Issue with sympathetic innervation
Pupil constricted- mitosis
Droopy eyelid- ptosis
No sweating- anhidrosis

Question 12

What does the ventricular system consist of and how does it work?

Answer 12

Otolith organs- utricle and saccule-
Utricle- detects left right head tilt- macula horizontal
Saccule- detects up down head tilt- macula vertical

Semicircular canals- detect rotation- ampulla with with hair cells in cupula inside is main unit of them and is pushed one way or other by endolymph

Question 13

Where is hearing processed and how is sound localised?

Answer 13

Processed eventually by the medial geniculate nucleus

Superior olivary nucleus is where sound localisation is done:
Medial SON detects time difference in sound from each ear to localise. Done at low frequency sound
Lateral SON detect sound intensity difference between ears and done for high frequency sound

Question 14

What is affected and what is the result of erbs palsy and klumfes paresis?

Answer 14

Erbs- damage to C5 root- arm hangs loosely at side- no bicep reflex

Klumpfe- T1 root damage- no sensation or use of small muscles of hand

Question 15

How are osteoblasts and clasts regulated?

Answer 15

Calcitonin from thyroid encourages osteoblasts to lay down new bone.
PTH from parathyroid gland encourage osteoclast resorption.

Osteoblasts also regulate- produce RANKL to activate osteoclasts and produces OPG to block RANKL and stop osteoclast activation

Question 16

What is the key triple therapy for rheumatoid arthritis?

Answer 16

Sulphasalazine, chloroquine and methotrexate

Question 17

What is Alzheimers disease?

Answer 17

Most common form of dementia in all ages
Beta amyloid plaques, tau tangles and decreased acetylcholine
Mostly temporal lobe atrophy
1 in 6 chance over 80
2 x more common in women
Treat with Donepezil- acetylcholine esterase inhibitor and memantine- NMDA antagonist to block affect of excess glutamate and help memory

Question 18

What is vascular dementia?

Answer 18

2nd most common dementia in over 65’s
Caused by issue with blood supply to brain- step wise progression
Affects more men than women

Question 19

What is dementia with levy bodies?

Answer 19

Affects 15% of people with dementia
Mix of Alzheimers and Parkinson’s symptoms
Build of of Lewy bodies of alpha synucelin
Hard to treat- no specific treatment, give ACHe inhibitors for hallucinations

Question 20

What are the 2 types of frontotemporal dementia?

Answer 20

Less common in over 65’s
Second most common in under 65’s
Often due to mutation in tau gene

Behavioural variant/ picks disease-
more common
change in personality and behaviour
lose inhibitions
change in appetite

Primary progressive aphasia-
language difficulties
reduced comprehension
speech problems

Question 21

What is glaucoma and what is the treatment?

Answer 21

Issue with drainage of aqueous humour produced by ciliary body in anterior chamber of eye.
Usually drains via trabecular network into schlemms canal located at join of cornea and sclera.

Open angle glaucoma- trabecular network clogged over time, slow onset vision loss

Closed angle- iris bows and closes anterior chamber angle and blocks drainage- sudden onset vision loss and pain

Treatment:
beta blockers to reduce amount of aqueous humour
alpha agonists to reduce the amount
carbonic anhydrase inhibitors to reduce amount
Prostaglandin analogues to increase aqueous humour drainage
muscarinic agonists to increase trabecular outflow

Question 22

How is vision processed?

Answer 22

From lateral geniculate nucleus it is sent to occipital lobe by magnocellular and parvocellular cells.

Magnocellular cells are the bottom 2 layers and are large cells that receive inputs from A parasol ganglion cells- greyscale

Parvoceullular cells are small cells in top 4 layers that get inputs from midget ganglion cells

Primary visual cortex sends things via 2 streams-
inferotemporal cortex- what pathway
posterior parietal cortex- where pathway

Question 23

What are the areas of cerebellum and what happens in cerebellar dysfunction?

Answer 23

Vermis/ vestibulocerebellum- balance
Paravermis/ spinocerebellum- postural tone
Cerebellar hemispheres- fine coordination

V-vertigo
A-ataxia
N-nystagmus
I-intention tremor
S-lurred speech
H-hypotonia
D-dysmetria, dysdiadochokinesis

Question 24

What is Menieres syndrome?

Answer 24

Increase in volume of endolymph disrupts function of labyrinth in ear, get temporary attacks of vertigo, deafness and nausea and vomiting
No cure but can treat nausea and vertigo

Question 25

What is benign paroxysmal positional vertigo (BPPV)?

Answer 25

Causes by calcium carbonate otolith crystals becoming dislodged from otolith organs and disrupting endolymph flow in semicircular canals.
Sudden dizziness on moving head, nausea and vomiting
Treat with epley or semont manoeuvre to reposition crystals

Question 26

What are the parts and the functions of the cochlea?

Answer 26

Scala media

Question 27

What are the parts and the functions of the cochlea?

Answer 27

Scala media and cochlear lymph filled with endolymph
Scala vestibuli and tympani filled with perilymph

Reissners membrane separates vestibuli and media
Basilar membrane separates scala media and tympani- organ of corti on basilar membrane

Footplate of stapes vibrates in oval window- wave goes along Scala vestibuli in perilymph and displaces basilar membrane- high pitch displaces closer and low pitched further away. Vibrations then go back along Scala tympani to round window.

Organ of corti has hair cells and displacement of basilar membrane displaces hair cells and causes depolarisation- send signal down CN VIII.

Question 28

What are the ossicles and muscles affecting them?

Answer 28

Outside to in: Malleus, incus, stapes

Tensor tympani- malleus- mandibular part of trigeminal nerve- chewing

Stapedius- stapes- facial nerve- speaking