mskderm 2 Flashcards

Question

actions of splenius capitis and splenius cervicis (superficial intrinsic back muscles)

Answer 1

* when acting unilaterally: **lateral flexion** of NECK and **rotation** of HEAD to *side of active muscles* * when acting bilatrally: **extension** of HEAD and NECK

Answer 2

* when acting unilaterally: **lateral flexion** of VERTEBRAL COLUMN to *side of active muscles* * when acting bilaterally: **extension** of VERTEBRAL COLUMN

Answer 3

* when acting unilaterally: **rotation** of HEAD *contralaterally* * when acting bilaterally: **extension** of HEAD and NECK

Answer 4

**posterior** rami of spinal nerves ## Footnote extrinsic back muscles are NOT, they are supplied by **anterior** rami

Answer 5

* conus medullaris: **tapering** **INFERIOR end** of spinal cord * cauda equina: collection of nerves that **extend below end** of spinal cord

Answer 6

* **vestigial** remnant of spinal cord * descends from conus medullaris to coccyx * function: **anchors** spinal cord in place -> preventing its movement **within vertebral column**

Answer 7

superficial -> deep: * dura mater * arachnoid mater * pia mater

Answer 8

* **tough**, fibrous, **protective** sheath * anchors spinal cord * runs from foramen magnum and attaches to **coccyx** via **filum terminale** (and thus ends at **S2** level) * **EPIdural** space (= above dura mater): contains internal vertebral venous plexus and epidural fat => site for epidural **anesthesia**

Answer 9

* **thin** middle layer * connected to pia mater via arachnoid **trabeculae** * **SUBarachnoid** space (= below arachnoid mater): filled with **cerebrospinal fluid (CSF)** => site for **lumbar puncture**

Answer 10

* **delicate** innermost layer * attach to dura mater via **denticulate** ligaments (pierces arachnoid mater to do so) * functions: 1. rich in **blood vessels** => supply **nutrients** 2. helps to **anchor** spinal cord in place

Answer 11

* ligaments @ anterior side: limit **extension** of spine * ligaments @ posterior side: limit **flexion** of spine * ligaments @ lateral side: limit **lateral flexion and rotation** of spine ## Footnote nuchal ligament (external occipital protuberance -> C7) is continuous with supraspinous ligament (C7 -> sacru,), and is formed via its thickening

Answer 12

posterior longitudinal ligament is **weaker** than anterior longitudinal ligament

Answer 13

1. injury to intervertebral **disc**: lumbar **flexion** → increase disc pressure → hernation ⇒ pain 2. pathology related to **facet joints** of the vertebral column (e.g. OA): lumbar **extension** (and rotation) → **more loading** of facet joints ⇒ more pain

Answer 14

* stages: a. normal disc b. **degeneration** (= *annulus* WEAKENS) c. **prolapse** (= *nucleus pulposus* PUSHES OUTWARD, annulus still intact) d.**extrusion** (= *nucleus pulposus* BREAKS THROUGH *annulus*) and **sequestration** (= *nucleus material* free fragment in canal) * mechanism of symptoms: a. **posterior** herniation ⇒ compression of **spinal cord** (i.e. myelopathy) b. **posterolateral** herniation ⇒ compression of **nerve roots** (i.e. radiculopathy)

Answer 15

## Footnote note: intertrochanteric **line** is found on **anterior** side while intertrochanteric **crest** is found on **posterior** side

Answer 16

serves as attachment point for **muscles**

Answer 17

* medial circumflex artery * **FRACTURE** of *neck* of femur → **avascular necrosis** of *head* of femur ## Footnote * bcos medial circumflex artery has a **retrograde** blood supply (i.e. blood travels "backwards" from distal end to proximal end) * does NOT occur in children as **obturator** artery provides significant blood supply to head in childhood

Answer 18

* *head of femur* **fits nicely** into *acetabulum*, which is **deepened** by acetabular **labrum** * ligaments: **ilio**femoral ligament, **pubo**femoral ligament, **ischio**femoral ligament * muscles: muscles around hip joint

Answer 19

* iliofemoral (anterior): prevents hyper**extension** of hip pubofemoral (more inferior): prevents over**abduction** of hip ischiofemoral (posterior): also prevents hyper**extension** of hip * strongest = **iliofemoral**

Answer 20

* synovial **ball-and-socket** joint * flexion/extension, abduction/adduction, external/internal rotation ## Footnote think of the **FABER** test, which involves putting patient's tested leg in "figure 4" position, which involves **F**lexion, **AB**duction and **E**xternal **R**otation

Answer 21

* The terminal branch of the femoral nerve is the **saphenous** nerve * This nerve only has **sensory** function, and travels with the **great saphenous vein** ## Footnote note: sural nerve is formed by union of 2 branches, a branch from the tibial nerve and a branch from the common fibular nerve

Answer 22

* The **great** saphenous vein ascends **anterior** to the **MEDIAL malleolus**, and drains into the **femoral** vein. * The **small** saphenous vein ascends **posterior** to the **LATERAL malleolus**, and drains into the **popliteal** vein.

Answer 23

pathway of femoral artery: * becomes femoral artery from **external iliac** artery upon passing **inguinal ligament** * into **femoral triangle** where it divides into **profunda femoris** and main femoral artery * **medial and lateral circumflex arteries** branch out from profunda femoris * while main femoral artery continues as **popliteal** artery upon passing **adductor hiatus** * popliteal artery divides into **anterior and posterior tibial arteries** after passing **lower border of popliteus** * **anterior** tibial artery continues as **dorsalis pedis artery**

Answer 24

1. gluteus maximus: **EXTENDS** and **externally rotates** hip, **inferior** gluteal nerve 2. gluteus medius and gluteus minimus: **ABDUCT** and **internally rotate** hip, **superior** gluteal nerve ## Footnote to understand action, think abt *origin* and/or *insertion* of each muscle! * gluteus maximus *originates* at **POSTERIOR** surface of body in general, and mostly ends in **iliotibial tract** which *inserts* at **LATERAL tibial condyle** * gluteus medius and minimus *originate* at **POSTERIOR** surface of body in general, but *insert* at **LATERAL and ANTERIOR surface of greater trochanter** respectively

Answer 25

* get patient to **raise one leg** off the floor * muscles on the *side of the foot on the ground* holds the pelvis ⇒ **prevents pelvis from sagging** on *side of raised leg* * (+) test: **pelvis falls** on the *side of the raised limb* ← hip **ABDUCTORS** (**gluteus medius and gluteus minimus**) on *other side* are **not functioning**

Answer 26

* piriformis, obturator internus, quadratus femoris: **nerve to** (...muscle name...) * obturator externus: **obturator** nerve ## Footnote think of it as obturator *externus* = *outcast* = thus *diff* innervation *from the rest*

Answer 27

* **hip ADDUCTORS** 1. **pectineus**: *obturator* **AND femoral** nerves 2. adductor brevis and adductor longus: *obturator* nerve 3. **adductor magnus**: *obturator* nerve (for adductor pt) **AND tibial portion of sciatic nerve** (for hamstring pt) * weirdo: 1. **gracilis**: hip ADDUCTOR **and knee FLEXOR**, *obturator* nerve ## Footnote * technically it is the muscles that are most proximal (pectineus) and most distal (adductor magnus) * from superficial → deep: adductor magnus, adductor brevis, adductor longus

Answer 28

* found in **quadriceps** tendon * dislocates **laterally** ← due to **upward lateral pull** by **quadriceps**

Answer 29

* floor: medial side of **tibia, talus and calcaneus** * roof: flexor retinaculum

Answer 30

* **medial** compartment of LEG: tendons of **T**ibalis posterior, flexor **D**igitorum longus and flexor **H**allucis longus ("**Tom, Dick and Harry**") * NAV in posterior LEG: **posterior tibial** artery and vein, **tibial** nerve

Answer 31

* lateral femoral cutaneous nerve * **obturator** nerve (anterior division, **L2-L4**) * **femoral** nerve (posterior division, **L2-L4**) ## Footnote lateral cutaneous nerve only comes into play for **sensory** innervation, where it takes over **lateral** side of THIGH

Answer 32

* superior and inferior **gluteal** nerves * **sciatic** nerve (**L4-S3**)

Answer 33

"**Tiger Cubs Need MILC**" * **T**alus * **C**alcaneus * **N**avicular * cuneiforms (**M**edial, **I**ntermediate, **L**ateral) * **C**uboid

Answer 34

* talus * calcaneus * navicular * cuneiforms (medial, intermediate, lateral) * **medial 3** metatarsals

Answer 35

* keystone: *talus* → **receive body's weight** from tibia and **distributes it** along both sides of arch * intersegmental ties: plantar *calcaneonavicular* (*spring*) ligament → ties inferior edges of bones tgt and **maintain alignment** * tiebeams: *plantar aponeurosis* and *intrinsic muscles of foot on medial side* (e.g. abductor hallucis) → resists outward thrust of arch and **keep bones** in arch **from spreading apart** * slings: *tibialis* anterior and posterior, *flexor hallucis longus* → **INVERT and plantarflex** foot when they contract ⇒ **pull arch upwards**

Answer 36

* keystone: *cuboid* → **midpt** → thus **receives downard body weight** and **distributes it** along both sides of arch * intersegmental ties: *SHORT plantar* (*calcaneocuboid*) and *LONG plantar* ligaments → ties inferior edges of bones tgt and **maintain alignment** * tiebeams: *plantar aponeurosis* and *intrinsic muscles of foot on lateral side* → resists outward thrust of arch and **keep bones** in arch **from spreading apart** * slings: *fibularis* brevis and longus → **EVERT and plantarflex** foot when they contract ⇒ **pull arch upwards**

Answer 37

* calcaneus * cuboid * **lateral 2** metatarsals

Answer 38

* medial arch: **weight** bearing * lateral arch: walking and **propulsion**

Answer 39

"tiger cub needs **milcc**" * (**m**edial, **i**ntermediate and **l**ateral) **c**uneiforms * **c**uboid * metatarsal bases

Answer 40

inflammation of **plantar aponeurosis** due to compressive and tensile forces **at insertion** ## Footnote * plantar aponeurosis: thick band of **connective tissue** on the sole of the foot that connects the heel bone to the toes, providing **structural support** * compressive force = **standing** too long tensile force = prolonged **push-off** motions

Answer 41

* **superior** gluteal nerve emerges **above** the piriformis * whilst the **inferior** gluteal nerve emerges **below** the piriformis * sciatic nerve also emerges from **below** the piriformis muscle, appearing as a wide 2cm band ## Footnote all 3 pass through the GREATER sciatic foramen!

Answer 42

bring person into **cross-legged** position * flexion of BOTH hip and knee joints * **abduction** of THIGH

Answer 43

All muscles in the **posterior thigh** are innervated by the **tibial portion** of the *sciatic* nerve, except for the **SHORT head of the biceps femoris**, which is innervated by the **common fibular portion** of the *sciatic* nerve ## Footnote posterior thigh muscle are the **hamstring** muscles, which include biceps femoris (short and long head), semitendinosus and semimembranosus

Answer 44

* emerges from pelvis through **greater sciatic foramen** * **tibial** and **common fibular** COMPONENTS run together inside a single sheath in thigh * then divides into the terminal branches, **tibial** and **common fibular** NERVES at **upper end of popliteal fossa** * common fibular nerve runs down fossa, giving rise to **lateral cutaneous** nerve of CALF before winding around **neck of fibula** * it then pierces the fibularis longus muscle (thus going into the ant compartment) and divides into the terminal branches, **superficial** fibular and **deep** fibular nerve ## Footnote note: fibular = peroneal

Answer 45

1. skin 2. superficial fascia 3. deep cervical fascia 4. strap muscles 5. viscera of neck (including thyroid gland)

Answer 46

* omohyoid * sternothyroid * thyrohyoid * sternohyoid

Answer 47

* **pre**vertebral muscles * **flex** cervical spine => allow head to **nod forward** ## Footnote muscles posterior to cervical vertebrae = **post**vertebral muscles fn is to extend cervical spine => allow head to **extend backward**

Answer 48

* carotid artery * **internal** jugular vein * **vagus** nerve (= cranial nerve X) ## Footnote **internal** jugular vein is **deep** to SCM while *external* jugular vein is *superficial* to SCM

Answer 49

* brachial plexus: bet scalenus anterior and scalenus medius * phrenic nerve: anterior to scalenus anterior

Answer 50

* investing * prevertebral * pretracheal ## Footnote ALL 3 contribute to formation of carotid sheath!

Answer 51

1. C**4**: at **superior** border of **thyroid cartilage**, where **bifurcation** of common carotid artery occurs and where carotid **baroreceptors and chemoreceptors** are found 2. C**6**: at **inferior** border of **cricoid cartilage**, where larynx ends and trachea begins and pharynx ends and oesophagus begins

Answer 52

* **external** carotid artery: **neck** * internal carotid artery: inside cranial cavity

Answer 53

* superficial temporal artery * maxillary artery

Answer 54

* found around **carotid sheath** * arise from **CERVICAL plexus** * give off branches which supply **strap** muscles

Answer 55

* STA runs close to **external** laryngeal nerve * ITA runs close to **recurrent** laryngeal nerve ## Footnote both nerves supply the **larynx**

Answer 56

post-central gyrus ## Footnote which is in parietal lobe of cerebral cortex

Answer 57

* modalities: spino-thalamic: **N**on-discriminative (Crude) touch, **T**emperature, **P**ain DCML: **F**ine touch, **V**ibrations, (conscious) **P**roprioception * 2nd order neuron: spino-thalamic: located at spinal cord, *decussates at spinal cord* also DCML: located at medulla oblongata, *decussates at brainstem* ## Footnote * spino-thalamic pathway = "***N**ot* **T**hat ***P**atient*" * DCML = **F**eeling **V**ery ***P**atient*

Answer 58

**commisural** fibres that connect both hemispheres ## Footnote in fact the BIGGEST commisural fibre!

Answer 59

* astrocytes: form part of **BBB** * *oligodendrocytes*: form **myelin sheath** in CNS * microglia: **phagocytic** role (i.e. "policeman" of CNS) ## Footnote in PNS, *schwann* cells form the myelin sheath!

Answer 60

* parotid: pure **serous** gland => **darkest**/most purplish staining * submandibular: **mixed** gland * sublingual: pure **mucinous** gland => **lightest**/least purplish staining ## Footnote serous = watery secretions

Answer 61

CN IX (Glossopharyngeal gland) ## Footnote provides **parasympathetic** fibers that stimulate saliva production

Answer 62

* **thinnest** part of skull * **middle meningeal** artery runs underneath * thus trauma will result in intracranial **haemorrhage** ## Footnote anatomically, it is the meeting point of the 4 skull bones

Answer 63

* **S**kin * **C**onnective tissue * **A**poneurosis * **L**oose areolar tissue * **P**ericranium

Answer 64

recall: parotid gland looks like an inverted pyramid! * base (superior) is against zygomatic arch * apex (inferior) is behind angle of mandible

Answer 65

* general pathway: *UMN* originates in **motor cortex** → descends and synapses on *LMN* in **facial motor nucleus** → LMN then exits brainstem and its branches innervate **muscles of facial expression** * majority receive UMN input from BOTH cerebral hemispheres (**bilateral**) except for the part supplying **muscles of lower face**, which receives only **contralateral** input

Answer 66

* UMN lesion: **CONTRALATERAL lower face** weakness, upper face spared * LMN lesion: **IPSILATERAL entire face** weakness ← all LMNs to upper and lower facial muscles **travel together in the same peripheral nerve** ## Footnote since LMN lesion affects all the fibres traveling tgt in CN VII, * also affects parasympathetic fibres to lacrimal gland ⇒ decrease in **lacrimation** * and also special sensory fibres to ant 2/3 of tongue ⇒ loss of **taste** in ant 2/3 of tongue

Answer 67

* **mainly** supplied by branches of **ECA** with some **suppplementation** from branches of **ICA** * MAIN supply is by **facial** artery, which is a branch of **ECA**

Answer 68

* often caused by occlusion of **lenticulostriate** artery * results in interruption of blood flow to **posterior** limb of **internal capsule** (which is where corticobulbar and corticospinal fibres pass through) * presents with **CONTRALATERAL hemiparesis** of **(lower) face, arm and leg**

Answer 69

* sphincteric: functions to **CLOSE openings** (e.g. orbicularis) * levator: functions to **OPEN openings** (e.g. levator, depressor)

Answer 70

* can be divided into 2 areas by the **vertex-ear-chin** line * anterior to the line is supplied by **trigeminal** nerve (CN V) while posterior to the line is supplied by **cervical plexus** (C1-C4) * these 2 areas can be further divided into smaller areas: which division it is (**opthalmic (V1), maxillary (V2) or mandibular (V3)**) OR which rami it is (**ventral or dorsal**)

Answer 71

* **emisary** veins connect intracranial space and extracranial space (scalp) * as they have **NO valves**, **infections** from scalp can **spread into cranial cavity** -> inflammation -> increase in ICP => compress brain

Answer 72

* ICA enters skull through **carotid canal** * and then divides into **anterior** and **middle cerebral arteries** * vertebral arteries enter skull through **foramen magnum** * and merge to form **basilar artery** * which ascends and eventually divides into the 2 **posterior cerebral arteries** ## Footnote vertebral arteries ← subclavian arteries

Answer 73

both are in the **occipital** lobe * primary visual cortex (VC1) is at area 17, on both banks of the **calcarine sulcus** * visual association area (VC2) is at areas 18 and 19, **adjacent** to VC1 ## Footnote note: both have **BILATERAL** representation

Answer 74

* VC1: basic, low-level visual processing (i.e. it **sees** but does not understand) * VC2: higher-level visual processing, (i.e. it **UNDERSTANDS**) via 2 visual pathways: 1. ventral visual pathway: processing of **form and colour** info ('**WHAT**') 2. dorsal visual pathway: processing of **spatial** relationships and **motion** info ('**WHERE**')

Answer 75

* Broca's **motor** speech area: frontal lobe, at areas 44 and 45 * Wernike's **sensory** speech area: temporal lobe, at area 22 ## Footnote note: both are mainly "found" in **ONE** hemisphere only, the **dominant** one!

Answer 76

* motor speech area: responsible in **expressing/producing** language * sensory speech area: responsible in **understanding** language

Answer 77

* **temporal** lobe * areas 41 and 42, surrounded by Wernicke's sensory speech ara ## Footnote note: it has **BILATERAL** representation

Answer 78

* is formed mainly by **frontal** and **ethmoid** bones, and partly by **LESSER wings of sphenoid** bone * is where the **frontal** lobe of the brain sits * contains many small openings known as the **cribiform plate**, which the **olfactory** nerve (= CN I) pass through to supply the roof of the nose

Answer 79

* is formed by **greater wings and body of sphenoid** bone, as well as **part of temporal** bone * is where the **temporal** and **parietal** lobes of the brain sit * has a depression ON the body of sphenoid known as the **hypophyseal fossa**, where the **pituitary gland** sits * and LATERAL to the body of the sphenoid is occupied by the **cavernous** sinus on each side

Answer 80

* two round openings ANTERIOR and lateral to the depression, known as the **optic canal**, which the **optic** nerve (= CN **II**) and **opthalmic artery** pass through * long-ish opening bet lesser and greater wings of sphenoid bone, known as the **superior orbital fissure**, which CNs **III, IV, V1 and VI,** as well as **opthalmic vein** pass through * round opening POSTERIOR to SOF, known as foramen **ovale**, which CN **V2** pass through * opening POSTERIOR and lateral to foramen ovale, known as foramen **rotundum**, which CN **V3** pass through * smaller opening slightly POSTERIOR to foramen rotundum, known as foramen **spinosum**, which **middle meningeal artery** pass through

Answer 81

* is separated from MCF by **PETROUS part of temporal bone**

Answer 82

* opening which IJV passes through, known as **jugular** foramen, which CNs **IX, X and XI** also pass through * opening which sits on **posterior** side of petrous part of temporal bone, known as **internal acoustic meatus**, which CNs **VII and VIII** pass through * **pair** of openings slightly anterior to foramen magnum, known as **hypoglossal** canal, which CN **XII** passes through

Answer 83

middle cerebral artery

Answer 84

occupy fissures/grooves -> prevent brain from moving too much => protection of brain

Answer 85

subarachnoid space => any rupture/aneurysm results in subarachnoid haemorrhage | a type of intracranial haemorrhage! ## Footnote aneurysm commonly occurs in circle of Willis and arch of aorta

Answer 86

epidural space => any rupture results in epidural haemorrhage | a type of intracranial haemorrhage!

Answer 87

Superior Sagittal Sinus via arachnoid granulations ## Footnote arachnoid granulations = projections of arachnoid layer into SSS

Answer 88

**choroid** plexus (= modificed capillaries) on the WALLS of **ventricles**

Answer 89

1d, 2b, 3a, 4c

Answer 90

* **clear** fluid resembling blood plasma, but **less protein** * found in subarachnoid space, ventricles and central canal of spinal cord * functions: 1. support and **cushion** CNS 2. **nourish** CNS 3. **remove waste** metabolites

Answer 91

2 routes for spread of infection: 1. **emissary veins** connect them to extracranial venous plexuses 2. **opthalmic vein**, which drains face and scalp, also drain into them

Answer 92

CS is **CLOSELY** related to multiple **cranial nerves** and the **ICA** ⇒ infection in CS can easily affect these structures ## Footnote the cranial nerves are the ones which pass through * SOF (CNs III, IV, V1, VI) * foramen rotundum (V2)

Answer 93

**bridging** veins * found in **subdural** space * allow for communication bet **cerebral veins** (in subarachnoid space) and **SSS**

Answer 94

* **subdural** space **increases** w/ AGE <- due to shrinkage of brain * **bridging** veins (which are in subdural space) are **more easily injured** during movements within cranial cavity => leading to **subdural hemorrhage**

Answer 95

* general: anterior 2/3 — mandibular div (= CN **V3**) posterior 1/3 + circumvallate papillae — glossopharyngeal (= CN **IX**) * special (taste): anterior 2/3 — facial (= CN **VII**) posterior 1/3 + circumvallate papillae — glossopharyngeal (= CN **IX**) ## Footnote circumvallate papillae is **located in anterior** 2/3 area, but has **same innervation as posterior** 1/3 due to it being originally from posterior 1/3 area but migrating forward during development

Answer 96

respiratory epithelium (pseudostratified ciliated columnar) ## Footnote same as rest of nasal cavity

Answer 97

* vestibule: lined by **skin** (stratified squamous epithelium) * olfactory mucosa: contains **nerve endings of CN I** (= olfactory nerve) for smell

Answer 98

nasolacrimal duct

Answer 99

* mainly **maxillary** sinus * but also **frontal** sinus and part of **ethmoidal** sinus

Answer 100

part of **ethmoidal** sinus

Answer 101

sphenoidal air sinus

Answer 102

1. **big distance** from floor of sinus to opening -> **accumulation** of e.g. mucus => infection 2. **close** proximity to **upper teeth** => infections can **spread** from there

Answer 103

* **trigemino**thalamic tract * crude and fine touch, temperature, pain, vibration, conscious proprioception, pressure * 1st order neuron: **trigeminal** ganglion (PNS), 2nd order neuron: **brainstem** (CNS) (decussates there too) ## Footnote recall that for rest of body: * *spino*thalamic and *DCML* tracts * spinothalamic: crude touch, temp, pain DCML: fine touch, vibration, pressure * both have 1st order neuron in DORSAL horn of*spinal cord* (PNS) but for 2nd order neuron, spinothalamic: *spinal cord* (decussates there too) DCML: *brainstem* (decussates there too)

Answer 104

* cortico**bulbar** / cortico**nuclear** tract * **voluntary** control of movements which are **discrete** and **skilled** * LMNs located in **motor nuclei** in **brainstem** <- receive cortiocobulbar fibres from UMNs in **one OR both** cerebral hemispheres ## Footnote recall that for rest of body: * cortico*spinal* tract * also *voluntary* control of movements which are *discrete* and *skilled* * LMNs located in VENTRAL horn of *spinal cord* <- receive corticospinal fibres usually from UMNs in *contralateral* cerebral hemisphere after they decussate at pyramids of medulla

Answer 105

* elevation and depression: PUPIL moves **upwards or downwards** * abduction and adduction: PUPIL moves **laterally or medially** * intorsion and extorsion: 12 O'CLOCK of eye **internally or externally rotates**

Answer 106

1(b), 2(d), 3(c), 4(a)

Answer 107

* hypoglossal nerve (= CN XII) * palatoglossus -> also considered a soft palate muscle => same innervation (Vagus, CN X)

Answer 108

tongue deviation to **ipsilateral** side when sticking out tongue ## Footnote * muscle responsible for protrusion of tongue = genioglossus * does so by BOTH (L and R) muscles working tgt * thus if e.g. R hypoglossal nerve is paralysed -> R genioglossus not working -> only L pushes forward unopposed => swings tongue over to opp side

Answer 109

* frenulum of **upper lip**, frenulum of **lower lip**: connects respective lip to *gingiva* -> limit movement of lip * frenulum of tongue: connects **tongue** to *floor of oral cavity* -> provide stability to tongue and support its movements ## Footnote `

Answer 110

No * **ant** 2/3 is located in **oral** cavity * **pos** 1/3 is located in oro**pharynx**

Answer 111

pure **serous** ## Footnote recall! serous = watery secretions which makes sense cos u cry water not mucous

Answer 112

Facial nerve (= CN VII) carries taste sensation from anterior 2/3 of tongue via **chorda tympani**, which hitchhikes through the infratemporal fossa by staying within **lingual nerve** (a branch of mandibular nerve (= CN V3). Note that it also has **secretomotor** component, and carries preganglionic fibres which travel into the **submandibular** ganglion (parasymp), where it synapses with postganglionic fibres which then supply the **submandibular and sublingual glands** in the floor of the mouth.

Answer 113

* *lingual* tonsil: OROpharynx, dorsal surface of **posterior 1/3 of tongue** * *palatine* tonsil: OROpharynx. **bet palatoglossal and palatopharyngeal folds** * *pharyngeal* tonsil: NASOpharynx, on posterior slope of **pharynx**

Answer 114

* temporal bone: mandibular fossa and articular tubercle * mandible: condyle

Answer 115

synovial modified hinge joint * hinge = depression and elevation * modified = protrusion and retraction AND lateral movement

Answer 116

BOTH facilitate **lateral** movements but * Upper facilitates **sliding** movements (i.e. protrusion, retraction) * Lower facilitates **hinge** movements (i.e. elevation and depression)

Answer 117

* muscles of mastication * suprahyoid muscles

Answer 118

* terminal branch of ECA which enters infratemporal fossa **AFTER the split at parotid gland** * gives off many **branches** while within infratemporal fossa, such as **MMA**, branches to **muscles of mastication**, **parotid gland**, etc * subsequently enters **pterygopalatine fossa**

Answer 119

* deep to **zygomatic arch** and ramus of **mandible** * anything in face at level of zygomatic arch or below

Answer 120

C) Lateral ligament * both capsular and lateral ligaments are direct ligaments * while stylo**mandibular** and spheno**mandibular** joints are **indirect** ligaments

Answer 121

1a), 2b), 3d), 4c)

Answer 122

* ECA * and some of its branches (e.g. lingual, facial, ...)

Answer 123

sublingual **papilla**, which is a pair of openings just **beside frenulum** of tongue

Answer 124

1. oral cavity **proper**: bet upper and lower lips, **behind teeth** 2. oral **vestibule**: bet teeth and lips + bet teeth and cheeks

Answer 125

oropharyngeal isthmus * superior: soft palate * inferior: posterior 1/3 of tongue * lateral: palatoglossal fold ## Footnote both the palatoglossal and palatopharyngeal folds each consists of a mucosa covering the underlying muscle!

Answer 126

sulcus terminalis, which is a V-shaped groove

Answer 127

1. vallecula: space bet **epiglottis** and posterior 1/3 of **tongue** 2. piriform recess: long, vertical fold bet **laryngopharynx** and tube of **larynx**

Answer 128

* sclera * cornea

Answer 129

* choroid * ciliary body <- formed by expansion of choroid * lens <- suspended from ciliary body

Answer 130

* optic disc * where optic nerve **exits** orbit

Answer 131

* larger area: macula pinpoint area: fovea centralis * macula = area with **high concentration of cones**, responsible for **visual acuity** and **colour vision** * fovea centralis is just the area with the **HIGHEST** concentration of cons

Answer 132

The nervous layer of the retina contains 3 important cell types: **photoreceptors**, **bipolar** cells and **ganglion** cells. Photoreceptors receive and **transduce** light energy to action potentials -> bipolar cells **transmit info** => ganglion cells, of which their **axons** will form converge to form **optic nerve**

Answer 133

1. medial rectus only ABducts and lateral rectus only ADducts 2. "**SIN** *RAD*": * **S**uperior ... = **IN**torsion * ... *R* ectus (except MR and LR) = *AD* duction

Answer 134

* ALL by CN **III** (= occulomotor nerve) * except **superior oblique**, which is innervated by CN **IV** (= trochlear nerve) * and **lateral rectus**, which is innervated by CN **VI** (= abducens nerve)

Answer 135

since it innervates the majority, easier to think abt what it does NOT innervate * rest: ptosis, pupil dilation, **downward and out** affected eye * diplopia: all directions EXCEPT **lateral** gaze to **affected side** ## Footnote * ptosis bcos CN III also innervates LPS muscles * pupil dilation bcos CN III also innervates sphincter pupillae muscle

Answer 136

* rest: **elevation** of affected eye * diplopia: worsens on **adduction** AND on head **tilt** to **affected side** ## Footnote * when eye is adducted, strongest depressor = SO ↔ when eye is abducted, strongest depressor = IR * tilting your head to one side => eye on that side intorts AND eye on other side extorts as compensatory mechanism to keep the world upright

Answer 137

* rest: **adduction** of affected eye * movement: FAILURE of **abduction** of affected eye * diplopia: **lateral** gaze to **affected side**

Answer 138

NO Müller's is an **extension** of LPS but they are funtionally distinct * LPS: supplied by CN **III**, *voluntary* and **complete elevation of eyelid** * Müller's: supplied by sympathetic fibres from **superior cervical ganglion**, *baseline* tone to keep eyelid **slightly elevated**

Answer 139

NO * 1º neuron: from hypothalamus to spinal cord → anhidrosis of both IPSILATERAL **arm and face** * 2º neuron: apex of lungs to superior cervical ganglion → anhidrosis of **face** only * 3º neuron: along ICA and into skull to eye → **NO** anhidrosis | IPSILATERAL ← no decussation in sympathetic pathway! ## Footnote recall: triad of ipsilateral ptosis, miosis, anhidrosis

Answer 140

1. incisive fossa: carries nasopalatine nerve and sphenopalatine artery from *nasal cavity* to **anterior hard palate** 2. greater palatine foramen: carries greater palatine nerve and artery from *pterygopalatine fossa* to **posterior hard palate** 3. lesser palatine foramen: carries lesser palatine nerve and artery from *pterygopalatine fossa* to **soft palate**

Answer 141

contains opening of the **eustachian tube**, which helps to communicate bet nasopharynx and middle ear

Answer 142

* surface facing oral cavity is lined by **stratified sq** epithelium <- in contact with external envt * surface facing larynx is lined by **respiratory** epithelium (pseudostratified columnar) <- in contact with air only

Answer 143

* longitudinal => elevates pharynx during swallowing (-> shorten distance bolus has to travel) * circular => peristalsis ## Footnote * longitudinal musles: stylopharyngeus, salpingo-p and palato-p * circular muscles: superior, middle and inferior constrictors

Answer 144

* roof: floor of **ACF** * floor: **maxilla**, *maxillary SINUS* * medial: **nasal** cavity, *ethmoidal AIR CELLS* * lateral: **temporal** fossa * posterior: **MCF** ## Footnote recap! * ACF = mainly **frontal** bone, but also lesser wing of sphenoid bone * nasal cavity includes **lacrimal** and **ethmoid** bones

Answer 145

from superficial to deep: 1. skin and connective tissue 2. orbicularis oculi 3. tarsal plate: dense fibrous connective tissue containing tarsal glands 4. conjunctiva

Answer 146

clear membrane covering **sclera** and **INSIDE of eyelids**

Answer 147

* modified **sebaceous** glands found in tarsal plates * produce **meibum**, an oily substance that **prevents evaporation** of eye's tear film

Answer 148

preganglionic **parasympathetic** fibers arise from the superior salivatory **nucleus** in the pons -> travel in **CN VII (facial nerve)** -> joins with sympathetic fibres to form another nerve -> reaches **pterygopalatine ganglion** and **synapses** => joins zygomatic nerve (from **V2**) to lacrimal nerve (from **V1**) to reach the gland ## Footnote sensory innervation of the gland is by lacrimal nerve (from V1)!

Answer 149

UMN: - brisk reflexes - hypertonia LMN: - no reflexes - hypotonia - denervative changes: muscle wasting, **fasciculations**

Answer 150

* lesion in **spinal cord** * take out **LMN at at level** but takes out passing **UMN** also, resulting in **everything at level below lesion** having UMN signs

Answer 151

C3-5 “3, 4, 5 keeps the diaphragm alive”

Answer 152

S2-4 “2, 3, 4 keeps the shit off the floor”

Answer 153

peripheral neuropathy

Answer 154

L2-4 (mainly L3 and L4)

Answer 155

* cervical nerves exit **above** cervical vertebrae * thoracic nerves exit **below** thoracic vertebrae * lumbar nerves exit **below** lumbar vertebrae * sacral nerves exit **below** sacral vertebrae

Answer 156

* all supplied by **RLN** * except for **cricothyroid**, which is supplied by **ELN** ## Footnote RLN = recurrent laryngeal nerve ELN = external laryngeal nerve

Answer 157

contraction -> brings thyroid cartilage forwards -> **stretch/tense vocal folds** => produce **high-pitched** sounds

Answer 158

* all help in adduction * except for posterior **cricoarytenoid**, which rotate arytenoid cartilages away from e/o, thus bring vocal folds away from e/o

Answer 159

* **lateral 2/3** of **external** ear is made out of **cartilage** * rest of ear (medial 1/3 of external ear + middle ear + inner ear) is made out of bone, and housed in **petrous part of temporal bone**

Answer 160

* external and middle ear: branches of **maxillary** artery * inner ear: **labyrinthine** artery (← basilar artery) ## Footnote * branches of maxillary artery include ext auditory artery, tympanic artery, etc

Answer 161

6 surfaces * roof: formed by petrous part of temporal bone ⇒ superior relation: cranical cavity (MCF) * floor ⇒ **inferior** relation: **IJV** * **lateral** wall: formed by **tympanic membrane** ⇒ inside cavity, **chorda tympani runs across** wall * **medial** wall: can find promontory, which carries tympanic plexus (CN IX) **oval window** and round window * **anterior** wall: can find opening of **eustachian tube** and **tensor tympani** muscle ⇒ anterior relation: **ICA** * **posterior** wall: can find opening to **mastoid air cells** and **stapedius** muscle ⇒ posterior relation: **facial** nerve (CN VII)

Answer 162

* cochlea * vestibular system: semicircular canals, vestibule (utricle + saccule)

Answer 163

* malleus * incus * stapes

Answer 164

* receptors: **hair** cells in **Organ of Corti** * 1º neuron: **cochlear nerve** (CN **VIII**) in **cochlear/spiral GANGLION** at *base of cochlea* * ENTERS CC through *internal acoustic meatus* * 2º neuron: **cochlear NUCLEUS** in *pontomedullary junction* (brainstem) * 3º neuron: **medial genticulate NUCLEUS** in *thalamus* * ends off at 1º auditory cortex ## Footnote bilateral representation!

Answer 165

* receptors: **hair** cells (**maculae** in vestibule, **cristae ampullaris** in semicircular canals) * 1º neuron: **vestibular nerve** (CN **VIII**) in **vestibular (Scarpa's) GANGLION** at *base of ganglion* * ENTERS CC through *internal acoustic meatus* * 2º neuron: **vestibular NUCLEUS** in *pontomedullary junction* (brainstem) * 3º neuron: depends on which pathway (many diff pathways) ## Footnote bilateral representation!

Answer 166

* vestibule: **static** equilibrium (i.e. position of head when **head and body are NOT moving**) * semicircular canals: **dynamic** equilibrium (i.e. balance when **head IS moving**, e.g. rotation of head)

Answer 167

* sound waves are **blocked** from efficiently traveling through the **outer or middle ear** to the inner ear * mechanical obstruction (e.g. ear wax), otitis media, perforated eardrum * Rinne: **bone > air** conduction ← air conduction ends at affected outer/middle ear while bone conduction bypasses lesion Weber: **louder** at (i.e. localises to) **affected ear** ← background noise is blocked out by affected outer/middle ear

Answer 168

* problem in **inner ear** or CN **VIII** * **age-related** hearing loss, **noise-related** hearing loss, tumours/infections of inner ear * Rinne: **air > bone** conduction ← both conduction ends at affected portion but air conduction benefits from amplification Weber: **louder** at (i.e. localises to) **normal ear** ← just signal in affected side ending at affected portion

Answer 169

* ask patient to stand erect with **feet tgt** + **arms by side** and **eyes closed** for **1 min** * assess for **vestibular function** and **proprioception** * (+) sign: **swaying** observed ## Footnote * recall that balance requires at least 2 out of the 3 senses involved: 1) vision 2) vestibular function 3) proprioception * (+) sign = **sensory** ataxia **NOT cerebellar** ataxia which results in (-) sign as patient is unstable EVEN with eyes open

Answer 170

serves as attachment point for **patella ligament** ⇒ connects patella to tibia

Answer 171

* bony factors: articular surfaces **do NOT fit nicely**: **massive femoral** condyles vs **small and shallow tibial** condyles, **shallow** articular surfaces of **femur and patella** * ligaments: medial and lateral **collateral** ligaments, **cruciate** ligaments * muscles: surrounding muscles and tendons ## Footnote articular surfaces: 1. femorotibial articulations: femoral **condyles** with tibia **condyles**, with **menisci** in between 2. femoropatellar articulations: **patellar surface** of femur with patella

Answer 172

* modified **hinge** joint * flexion/extension, medial/lateral rotation * **capsule, synovial membrane, menisci and ligaments** have innervation in terms of proprioception and **pain sensation** * innervated by **femoral, obturator, tibial and common fibular** nerves

Answer 173

* to lock the knee joint, *knee* has to be *fully extended* with the *foot on the ground*, then femur **medially rotates** on the tibia ("screw home" mechanism) ⇒ results in knee being stable and suited for **weight bearing** * to unlock the knee joint, **popliteus** muscle contracts, and femur **laterally rotates** on the tibia ⇒ allows **flexion** of knee to occur ## Footnote femur medially rotating on tibia = tibia externally rotating on femur

Answer 174

* medial (tibial) collateral ligament (MCL): prevents **abduction** * lateral (fibula) collateral ligament (LCL): prevents **adduction** ## Footnote MUST UNDERSTAND THAT abduction → **tibia** moving away from midline → knee will collapse inwards as a result → medial joint space opening ⇒ MCL has to become taut and work hard to resist it

Answer 175

* anterior cruciate ligament (ACL): prevents **POSTERIOR displacement of femur** on tibia (= anterior movement of tibia relative to femur) and **hyperextension** of knee joint * posterior cruciate ligament (PCL): prevents **ANTERIOR displacement of femur** on tibia (= posterior movement of tibia relative to femur) and **hyperflexion** of knee joint ## Footnote think of their origins and insertions: * ACL originates at **ANTERIOR intercondylar** area of **tibia** → inserts at **POSTERIOR** part of **LATERAL femoral condyle** * PCL originates at **POSTERIOR intercondylar** area of **tibia** → inserts at **ANTERIOR** part of **medial femoral condyle** to understand extension/flexion, think of it this way! e.g. **extension** → **femur pushes tibia forward** slightly (= anterior movement of tibia relative to femur) ⇒ pulls on ACL

Answer 176

* ACL: anterior drawer test * PCL: posterior drawer test

Answer 177

1. **medial** meniscus is firmly **fixed to tibial collateral ligament** → lesser excursion during rotatory movements (i.e. lesser movements when flex/extend knee) ⇒ more likely to be crushed or torn 2. while **lateral** meniscus is **separated from fibular collateral ligament** by **popliteus** muscle AND **popliteus pulls** lateral meniscus **backwards** ⇒ preventing crushing bet articular surfaces 3. **medial** meniscus is **broader at the back** while lateral meniscus is more circular

Answer 178

* foot is planted, **knee** is slightly **flexed**, external rotation of tibia, boom **valgus force** (i.e. abduction of knee joint) applied **to lateral knee** * ligaments: 1. **MCL**: bcos of overabduction of knee joint 2. **ACL** 3. **medial meniscus**: bcos firmly attached to MCL

Answer 179

* **hip FLEXORS**: 1. iliacus: innervated by *femoral* nerve 2. **psoas major**: innervated directly by anterior rami of **L1-L4** * **knee EXTENSORS**: all innervated by *femoral* nerve 1. vastus medialis 2. vastus intermedius 3. vastus lateralis 4. **rectus femoris**: also doubles up as **hip flexor** * weirdo: 1. **sartorius**: **knee AND hip FLEXOR**, innervated by *femoral* nerve ## Footnote * hip flexors collectively known as iliopsoas * knee extensors collectively known as quadriceps femoris "the quads" * superficial to deep: sartorius, rectus femoris, rest of quadriceps femoris (vastus ...), iliopsoas

Answer 180

**hip EXTENSOR** and **knee FLEXOR** * semimembranosus and semitendinosus: innervated by **tibial portion of sciatic nerve** * bicep femoris (short and long head): **long head** innervated by **tibial portion of sciatic nerve**, **short head** innervated by **common fibular portion of sciatic nerve** ## Footnote collectively known as hamstring muscles

Answer 181

* ischial tuberosity * except short head of biceps femoris, which originates from **linea aspera**

Answer 182

* shared **insertion** point just **below medial condyle** of **tibia** * for **tendons** of these 3 muscles: **sartorius, gracilis and semitendinosus** * pathologies (e.g. bursitis) can **mimic MCL/medial meniscus** pain ← MCL lies just deep to it

Answer 183

* superior: inguinal ligament medial: adductor longus lateral: sartorius * femoral **N**erve, femoral **A**rtery, femoral **V**ein ## Footnote * **most medial** actually is femoral **canal**, which is lymphatic vessels and inguinal lymph nodes * artery, vein and canal are actually in a femoral **sheath**

Answer 184

* synovial **hinge** joint * *flexion* (= *plantar*flexion) / *extension* (= *dorsi*flexion) * distal end of **tibia** and **fibula** with **trochlea of talus** ## Footnote * the part of the tibia and fibula involved is also known as tibiofibular mortise * TMI, but posterior tibiofibular ligament is also actually part of the articular surface

Answer 185

* bony factors: tibiofibular mortise and pulley shaped trochlea of talus are fairly **congruent** * ligaments: 1. medial and lateral **collateral** ligaments, 2. **syndesmosis**, particularly the inferior transverse tibiofibular ligament * muscles: muscles surrounding the ankle which attach to bones of the foot ## Footnote ITTFL **deepens** the ankle mortise **posteriorly** and **prevents posterior translation** of the talus ⇒ contributes to stability of ankle joint

Answer 186

* TOP: proximal tibiofibular joint, which is a** synovial plane** joint, consisting of head of fibula articulating with lateral condyle of tibia * MIDDLE: **interosseous membrane** * BOTTOM: tibiofibular **syndesmosis**, which is a **fibrous** joint consisting of tibiofibular ligaments (AITFL, PITFL, ITTFL) and interosseous ligament, and contributes to **stability of ankle joint**

Answer 187

* inferior surface of **talus** with superior surface of **calcaneus** * **inversion** (= **sole** of foot faces **inwards**) / **eversion** (= **sole** of foot faces **outwards**)

Answer 188

**dorsiflexors**, innervated by **DEEP peroneal** nerve "**Tom, Dick, Harry ... and Terry**" * **T**ibialis anterior: **inverts** foot * extensor **D**igitorum longus: extends 2nd-5th toes * extensor **H**allucis longus: extends big toe * fibularis/peroneus **TER**tius: **everts** foot ## Footnote * **dorsi**flexion = **extension** of ankle joint * MAIN dorsiflexor = tibialis anterior

Answer 189

**extensor** *digitorum* brevis * **extends** *toes* * innervated by DEEP peroneal nerve

Answer 190

responsible for **eversion of foot** (and minorly **plantarflexion**), innervated by **SUPERFICIAL peroneal** nerve * fibularis/peroneus longus * fibularis/peroneus brevis ## Footnote note: tendons of these muscles run **posterior** to lateral malleolus

Answer 191

**plantarflexors**, innervated by **tibial** nerve * superficial 1. gastrocnemius: plantarflexes when **leg is straight**, **flexes knee** 2. soleus: plantarflexes when **leg is bent** 3. plantaris * deep 1. popliteus: **NOT** involved in **plantarflexion**, just unlocks knee 2. flexor hallucis longus: flexes big toe 3. tibialis posterior: also **inverts** foot 4. flexor digitorum longus: flexes 2nd-5th toes ## Footnote for deep muscles in posterior compartment, almost same as muscles in anterior compartment, * "Tom, Dick, Harry ... and Terry" → "Tom, Dick, Harry ... and Pops" * tibialis anterior inverts foot → tibialis posterior inverts foot

Answer 192

* **FDL** starts medially and ends laterally while **FHL** starts laterally and ends medially ⇒ point of **crossover** is Knot of Henry * allows **big toe** (FHL), which is the **primary propulsive** digit, to **distribute force to lateral toes** (via FDL) → enabling **coordinated push-off and stability** across the whole foot

Answer 193

* gastrocnemius and soleus * insert at posterior surface of calcaneus via their **common tendon** — **calcaneal (Achilles)** tendon * majority of **plantarflexion** force * rupture (e.g. Achilles rupture due to sudden strong pull) can result in loss of plantarflexion ⇒ cannot **stand on tiptoe** AND **gait** impaired (as cannot propel body forward)

Answer 194

* usually an **inversion** injury, involving a sprain of the **lateral** ligaments (commonly ATFL) * symptoms: pain at **lateral** ankle, **swelling** * will see +ve **anterior drawer** test * treatment: 1. acute pain relief 2. restore **ROM** ⇒ prevents stiffness 3. strengthen, esp **evertor** muscles as strain was likely due to **weak evertors** AND evertors need to **take over ligament function** post-strain 4. **proprioception** exercises (e.g. balance exercises) → retrains **neuromuscular control** after ligament injury ⇒ prevents recurrence ## Footnote * anterior drawer test of ANKLE: (+) test indicates excessive anterior translation of **talus** relative to **tibia** ⇒ **AFTL tear/laxity**

Answer 195

* usually an **eversion** injury, involving a sprain of the tibiofibular **syndesmosis** (commonly AITFL) * symptoms: pain at **SUPERIOR lateral** ankle, **NO swelling** * treatment: 1. **offloading** required 2. may require surgery

Answer 196

* tap **calcaneal** (Achilles) tendon * contraction of **triceps surae** * resulting in **plantarflexion** * **S1-S2**, lumbosacral plexus, **tibial** nerve ## Footnote * recall: triceps surae consists of gastrocnemius and soleus muscles * sciatic nerve has root values of L4-S3

Answer 197

* tap **ligamentum patellae** * contraction of **quadriceps femoris** muscle * resulting in **extension of knee** joint * **L2-L4**, lumbosacral pelis, **femoral** nerve ## Footnote ligamentum patellae is BELOW the patella! the one about the patella is quadriceps tendon

Answer 198

* acute: **fractures**, reperfusion injury, external compression, bleeding disorders * chronic: repetitive high-impact **activity** ## Footnote chronic: results in exercise-induced **increased muscle volume** that fascia cannot accommodate

Answer 199

* **muscle groups** are enclosed by inelastic fascia and thus **cannot expand** * pressure INSIDE compartment increase → **compartment pressure >> perfusion pressure** → ischaemia of muscles and nerves → which then results in **endothelial damage** → more **oedema** → **higher compartment pressure** → worse **ischaemia** ⇒ **positive feedback loop**

Answer 200

* early signs: pain **out of proportion**, pain on **passive stretch** of affected compartment * late signs: "6 Ps" 1. pain out of proportion 2. paresthesia (= tingling and numbness) 3. paralysis 4. pallor 5. poikilothermia (= cool limb) 6. pulselessness ## Footnote late signs: * (2) and (3) are due to nerve ischaemia * (4), (5) and (6) are due to compression on arteries

Answer 201

* **gastrocnemius crosses BOTH knee and ankle joints** while soleus only crosses ankle joint * **dorsiflexion** (opp action) when **KNEE IS BENT** tests ONLY **soleus** ← **gastrocnemius** is **slackened**

Answer 202

**upper outer** quadrant in order to **avoid sciatic nerve**, which runs diagonally (downwards, medially -> laterally) right under gluteus maximus

Answer 203

* motor: 1. paralysis of hamstrings ⇒ NO hip extension but **weak flexion of knee** 2. paralysis of all muscles below knee ⇒ NO dorsiflexion/plantarflexion of foot, inversion/eversion of foot. moving of toes AND **footdrop** * sensory: loss of sensation **below knee** EXCEPT medial side of leg and medial border of foot up to ball of big toe ## Footnote * all hamstring muscles carry out hip extension **AND knee flexion**, weird muscle in anterior compartment (**sartorius**) carries out hip flexion **AND knee flexion**, weird muscle in medial compartment (**gracilis**) carries out hip adduction **AND knee flexion**, THUS weak flexion of knee possible * footdrop occurs due to **weight of foot** and **gravity** * medial side ... still has sensory innervation as they are supplied by **saphenous** nerve (← branch of femoral nerve) * common causes of injury to sciatic nerve: 1. IM injection at wrong site of gluteus maximus 2. posterior dislocation of hip joint

Answer 204

* motor: paralysis of all muscles in anterior and lateral compartments of leg → unopposed actions of opposing muscles ⇒ plantarflexion of foot (**foot drop**) and **inversion** of foot * sensory: loss of sensation over **lateral side of leg** and **dorsum of foot and toes** EXCEPT medial border of foot up to ball of big toe and **lateral border** of foot ## Footnote * medial border of foot up to ball of big toe is innervated by saphenous nerve ← femoral nerve * lateral border of foot is innervated by sural nerve ← common fibular AND tibial nerve * common cause of injury to common fibular/peroneal nerve: fracture (or other injuries) at upper end of fibula

Answer 205

**perforating veins** connect superficial and deep veins → **valves** in them results in blood flowing in only 1 direction (**superficial vein -> deep vein**) → discourage **pooling** of blood **in superficial** veins ⇒ prevent **dilatation **of superficial veins (i.e. varicosity)

Answer 206

* superficial veins: **congenital weakness** of venous WALL * perforating veins: **incompetency** of venous **valves** ⇒ blood flowing in opp directioin * deep veins: **obstruction of deep** veins → prevents upwards flow of blood → **increased pressure** of **deep** veins ⇒ **pressure transmitted** to superficial veins a) physiological: **pregnancy** (baby compresses deep veins) b) pathological: **tumours**, DVT, ...

Answer 207

2 diff treatments for 2 diff phases * **chronic** varicose veins: polidocanol * **acute** bout of **inflammation** in **pre-existing** varicose veins: mucopolysaccharide polysulphate

Answer 208

"basically destroying veins so that better blood pathways can be used" * induce **endothelial damage** -> inflammation and fibrosis * formation of **thrombus** within vein -> ischaemia -> fibrosis and sclerosis => **obliteration of vessel**

Answer 209

* MAIN: **thromboembolism** * "allergic" side effects: e.g. redness, pruritus. anaphylaxis

Answer 210

* **anti-thrombotic** * *anti-inflammatory* * improves *microcirculation* * *analgesic* * fibroblast modulation ## Footnote * think abt the **cause** of the inflammation (could be **formation of thrombus**) AND the cardinal *signs* of acute *inflammation* (redness, *swelling*, warmth, *pain*, loss of fn) * fibroblast modulation = influence fibroblasts to take on anti-inflammatory role (instead of pro-inflammatory)

Answer 211

* "allergic" side effects: mild skin irritation, contact dermatitis, hypersensitivity

Answer 212

1. V3 2. V2 3. V1 4. V3 5. V3

Answer 213

* **trigeminothalamic** tract (proprioception) * 1st orer neuron found in **mesencephalic** NUCLEUS instead of trigeminal ganglion

Answer 214

* palatoglossus: depresses soft palate (and elevate tongue) → **closing oropharyngeal isthmus** ⇒ sealing oral cavity during **chewing** * tensor palatini: tenses and depresses soft palate ⇒ **pushing bolus** backwards during **swallowing** * palatopharyngeus: depresses soft palate and elevates pharynx ⇒ **further propulsion of bolus** during **swallowing**

Answer 215

orbicularis oculi ## Footnote to be exact, it is the **palpebral** part of OO which gently closes eyelids for **blinking** while **orbital** part is the outer portion that **tightly closes** the eyelids

Answer 216

* **1º visual cortex** (in occipital lobe) * **PCA** infarct ← macula spared due to **dual blood supply (PCA + MCA)**

Answer 217

* **E**ye-opening response (4), **V**erbal response (5), **M**otor response (6) * min: **3** (= no eye-opening response, no verbal response and no motor response) * max: **15** (= spontaneous eye-opening response, orientated verbal response and obeying commmands) * cutoff for concern is **< 12** | min is NOT 0!

Answer 218

* **D**ysdiadochokinesia * **D**ysmetria * **A**taxia (ipsilateral) * **S**canning / Staccato speech * **I**ntention tremor (= tremor that worsens as **target is approached**) * **N**ystagmus (= rhythmic, uncontrolled eye movements(esp gaze-invoked)) * **G**ait disturbance (= **broad-based**, unsteady, drunk-like gait)

Answer 219

* cause: cerebral **HYPOPERFUSION** * types: a) **NEUROgenic** 1. **vasovagal**: (where increased vagal tone → bradycardia + vasodilation) **hot, closed, crowded** areas w/ poor ventilation, prolonged **standing**, **painful** stimuli, **fear** or **shock** 2. reflex-mediated **situational** syncope: increased vagal stimulation due to e.g **straining (micturition/defecation)** 3. **orthostatic**: occurs **upon becoming upright** b) **CARDIOgenic**: (where there is sudden reduction in cardiac output) cardiac **arrhythmias**, cardiac **defects** and **cardiomyopathy** ## Footnote hypoglycaemia ≠ cause of syncope since it does NOT cause cerebral hypoperfusion!

Answer 220

* **postural BP** measurement ⇒ to rule out **orthostatic** syncope * **ECG** ⇒ to rule out **cardiogenic** syncope

Answer 221

NO * seizure: results from an **acute** systemic metabolic disturbance, or an **acute** disturbance of brain structure or metabolism * epilepsy: **chronic** condition characterised by a predisposition to **recurrent**, usually spontaneous **seizures**

Answer 222

nerve conduction study * involves stimulating nerve at 1 point and measuring response at another point ⇒ measure **velocity** and **amplitude** of signal * **demyelinating** (e.g. GBS): decreased **velocity** (← myelin = insulation for fast conduction) * **axonal** (e.g. diabetic neuropathy): decreased **amplitude** (← axon loss = fewer signals transmitted)

Answer 223

**glove and stocking** pattern, where **distal** nerves are affected **before proximal** ones

Answer 224

**molecular mimicry**! **C. jejuni** proteins resemble **axolemma** → cross-reactive **antibodies** ⇒ immune-mediated segmental **demyelination** and axonal degeneration ## Footnote axolemma = plasma membrane of axon

Answer 225

**Type II resp failure** cos GBS results in demyelination of muscles needed for respiration → hypoventilation ⇒ **CO2** builds up ## Footnote type **II** cos **high CO2** but normal (or low) O₂

Answer 226

weak **diaphragm** → **lying down** will result in **abdominal contents compressing** diaphragm ⇒ **breathless** (esp since **NO accessory muscles** to compensate) ## Footnote * diaphragm affected ← demyelination of phrenic nerve * accessory muscles affected ← demyelination of nerves supplying them

Answer 227

* ASCENDING **numbness** * ASCENDING **flaccid paralysis** later on * **NO muscle wasting** ← too **acute**

Answer 228

* DISTAL **sensory loss** * foot drop, pes cavus and hammer toes (← DISTAL **motor** loss) * DISTAL **muscle wasting** ("inverted champagne bottle legs") ← very **chronic** ## Footnote * leg: **dorsiflexors** and *evertors* tend to be affected first ⇒ **foot drop** and *pes cavus (= high arches)* * foot: **intrinsic mucles (interossei, lumbricals**) affected before extrinsic muscles (mainly FDL and FHL) ⇒ **hammer toes** (= hyperextension of metatarsophalangeal joints and flexion of PIP joints)

Answer 229

we all know to get patient to **clench their teeth**, and flex both sets of fingers into a **hook-like** form, and **interlock those sets of fingers** together... but what is this called? **JENDRASSIK** maneouvre

Answer 230

* **motor** weakness ONLY * **proximal** > distal weakness * **normal reflexes** * **increased creatine kinase** levels ← **breakdown of muscle membrane** results in **release** of CK from muscle cells

Answer 231

**electromyography** (EMG) * records electrical activity of **muscles**

Answer 232

**AUTOantibodies** bind to **postsynaptic** nicotinic ACh receptors (**AChRs**) → **competitive inhibition** of ACh binding, AChR **internalisation** and **complement activation** resulting in **damage** to postsynaptic membrane and muscle fibres themselves → poor **neuromuscular transmission** ⇒ **FATIGABLE skeletal muscle weakness**

Answer 233

* HALLMARK: **fatigable weakness** (worsens w/ **repeated activity**, and at **end of day** — diurnal variation) * **ocular**: ptosis (asymmetric), diplopia * **bulbar**: dysphagia, dysarthria * **respiratory** weakness (during MG **crisis**) * **PROXIMAL** *limb* **weakness** ## Footnote NO **sensory** loss NORMAL **reflexes**

Answer 234

* anti-**AChR** antibodies * **repetitive nerve stimulation** test: decremental response seen

Answer 235

**inhibits acetylcholinesterases** (AChE) → increased **conc of AC**h at NMJ → increased **neuromuscular transmission** ⇒ **symptom** control

Answer 236

**X**-linked mutation → **absence of dystrophin** (dystrophin usually links actin to ECM, thus making muscle fibre structurally stable) → **sarcolemma** becomes **vulnerable during contraction** → micro **tears** → **muscle fibre necrosis** and subsequently being **replaced by fat and connective tissue** ⇒ **weakness** AND **pseudoHYPERtrophy** ## Footnote * DMD is a XL**R** disorder * sarcolemma = **membrane** of a muscle fibre

Answer 237

* **PROXIMAL weakness** (starting from *pelvic girdle*) => (+) **Trendelenburg** sign, lumbar loidosis, **Gowers** sign * **cardiac** involvement ## Footnote Gowers sign = pushing up along thighs to stand

Answer 238

* symmetrical **PROXIMAL weakness** * **skin** manifestations: heliotrope rash, gottron papules, shawl / V-sign ← **dermal vessels** are also attacked * **perifascicular atrophy** ← **outer edges** of muscle fascicles are poorly perfused, resulting in **ischemia** and thus **atrophy** ## Footnote pathophysiology: **AUTOantibodies** attack **capillaries and arterioles** supplying muscles

Answer 239

**METASTASES** (i.e. 2º brain tumour) ## Footnote but otherwise most commo 1º brain tumours are meningiomas and gliomas

Answer 240

* **ependymoma**: from ependymal cells lining *ventricles* * *germ cell tumours*: from primitive germ cells that migrate along the body's *midline* during fetal developmen * medulloblastoma: immature *neurons* in cerebellum * **pilocytic astrocytoma**: from *astrocytes*

Answer 241

* gross: **whorled** cut surface histo: **whorl** formation * associated with **children**, associated w/ **NF-2** syndrome

Answer 242

* rosettes * pseudorosettes

Answer 243

craniopharyngioma * formed from embryonal remnants * contains yellow, viscou fluid resembling **'engine oil'**

Answer 244

* affects **cerebellum** * **sheets** of **small round blue** cells, "**carrot** shaped" nuclei, rosettes * associated w/ **children** ## Footnote * histo: 1. similar to **medullary** IDC (breast cancer) which also has tumour cells arranged in **sheets** 2. must NOT confuse w/ **Ewing** sarcoma, which also has **small round uniform blue** cells * in contrast, **mature** neuronal tumours (e.g. central neurocytoma) are associated w/**adults**

Answer 245

* **IDH** mutation determines **prognosis** * IDH **mutant** > wild type

Answer 246

* IDH **wild-type** => **very poor** mean survival * gross: haemorrhage, *necrosis* * histo: **palisading** *necrosis*, microvascular proliferation

Answer 247

* whole arm **deletion** of **1p** and **19q** in **chromosomes** => responsive to **chemotherapy** * histo: uniformed round cells with **'FRIED EGG'** appearance

Answer 248

all **AD**

Answer 249

B. NF2 | recall: schwannomas are **benign**! ## Footnote NF2 also associated with other neural tumours like **meningioma** while NF1 is more associated ith neural tumours like **neurofibroma**

Answer 250

D. Tuberous sclerosis ## Footnote other clinical features of TS are * **cortical tubers** in the brain * **SKIN lesions**: Shagreen patch, Ungual fibromas, Ash leaf patches

Answer 251

D. VHL ## Footnote other clinical features of VHL are * haemangioblastomas (usually retinal) * renal cell carcinoma * pheochromocytoma * endolymphatic sac tumour (in inner ear)

Answer 252

a) tuberculous **meningitis** - involves **base of brain** - eventually lead to tuberculoma formation, seen GROSSLY as **white granules** b) **tuberculoma**: - from infection of brain parenchyma - seen as a **ring-enhancing lesion** on IMAGING

Answer 253

spina bifida

Answer 254

* anterior (superficial -> deep): masseter, ramus of mandible, medial pterygoid * posterior (superficial -> deep): **SCM**, mastoid process, **digastric muscle**, styloid process * medial: styloid process * lateral: skin, superficial fascia (containing platysma)

Answer 255

**N**e**VA** * facial **N**erve * RETROMANDIBULAR **V**ein * EC**A** and its terminal branches

Answer 256

TRAP * (resting) **T**remor * (lead pipe) **R**igidity * **A**kinesia * **P**ostural instability ## Footnote * can also have pill-rolling tremor, which is a type of resting tremor. and looks like a rhythmic, circular motion of rolling a small object, like a pill, between the thumb and forefinger * understand that dopamine: a) activates the direct pathway → facilitates movement b) Inhibits the indirect pathway → suppresses unwanted inhibition → excessive inhibition without dopamine → weak postural reflexes → body cannot realign quickly ⇒ imbalance

Answer 257

* face: **hypomimia** (mask-like facial expression), paucity of blinking, hypophonia * upper limb: **decremental** bradykinesia (reduced **arm swing** when walking, **micrographia**) * lower limb: **shuffling/festinant gait**, turning in numbers ## Footnote decremental = decrease in amplitude and frequency w/ repeated movements

Answer 258

* Parkinsonism: **lead pipe** rigidity, where resistance is the **same regardless of joint position** * UMN rigidity: **clasp knife** rigidity, where resistance **varies** depending on joint position, with there being a sudden release of resistance towards the end ## Footnote notr: cogwheel rigidity = lead pipe rigidity + tremor

Answer 259

**pyramidal** * normal: corticospinal tract (**pyramidal**) **inhibits** reflexes and tone while **extrapyramidal** tracts **increase** tone * **corticospinal tract damaged** in UMN lesion → extrapyramidal tracts are now **unopposed** → **increased tone** (esp in flexors in UL and extensors in LL) and **overactive stetch reflex** ⇒ **involuntary** muscle **contractions** (= spasticity) ## Footnote **increased tone** in flexors in UL and extensors in LL => pyramidal pattern of weakness (**UL flexed** posture + **LL extended** posture) * can think of it as "anti-gravity" muscles are stronger and thus not as weak when lesion occurs, since: a) flexors in UL raise forearm and hand against gravity b) extensors in LL help you get up from sitting/squating position

Answer 260

* caused by anti-**dopaminergic** agents, such as **antipsychotics** (e.g. haloperidol, risperidone) and **metoclopramide** (anti-emetic) * tends to have more **symmetrical** involvement

Answer 261

**Wilson**'s disease * **AR** disease * **defect** in biliary **copper excretion** → **deposition** of copper in **basal ganglia** ⇒ parkinsonism ## Footnote * could also have deposition in: 1) **liver** ⇒ cirrhosis 2) eyes ⇒ **Kayser Fleischer rings** * diagnoised via 1) low levels of **caeruloplasmin** (copper transporter) 2) high **urinary** levels of **copper** * treatment: **penicillamine** → sequesters copper for **urinary excretion**

Answer 262

more **asymmetrical**

Answer 263

* motor symptoms: resting **T**remor, lead pipe **R**igidity, bradykinesia (**A**kinesia) * mood/psychiatry: **depression** and psychiatric symptoms (e.g. psychosis, hallucination) * cognition: cognitive impairment/deficits (e.g. dementia) * sleep/fatigue: severe fatigue, insomnia, excessive daytime sleepiness * autonomic: dysautonomia, **constipation**, sialorrhoea, **postural hypotension** * others: **anosmia**, pain ## Footnote general timeline of symptoms: 1. **anosmia** 2. **motor** symptoms 3. non-motor symptoms (e.g. autonomic symptoms)

Answer 264

**L**-DOPA w/ DOPA **decarboxylase inhibitor** * principle: to address **dopamine deficit** * L-DOPA used instead of dopamine as dopamine is **too large** to cross the **BBB** → will **remain in circulation** ⇒ **ineffective**, as well as create various **side effects** * DOPA decarboxylase inhibitor (e.g. **carbidopa**) used to inhibit DOPA decarboxylase and **prevent L-DOPA conversion** while it is still **periphery** ← works as **inhibitor** is **too large** to cross **BBB**, and thus **canot follow L-DOPA** into brain and prevent its conversion in CNS ## Footnote side effects include positive inotrope and chonotrope effects on heart, effects on BP and effects on kidney

Answer 265

NO! **alternative** agents (e.g. **dopamine agonists**) are preferred as the **efficacy** of L-DOPA + carbidopa **diminishes over time** and thus should be saved for when there is no choice

Answer 266

both involve cognitive impairment but **ADLs** are affected in **dementia**

Answer 267

1. **Alzheimer**'s disease — most most common! 2. **vascular** dementia: caused by multiple strokes (multi-infarct dementia) or chronic small vessel disease

Answer 268

**MRI** * Alzheimer's: **atrophy** of medial temporal lobe * vascular: white matter **hyperdensities** ## Footnote note: white matter, not grey matter! white matter (deeper, inner part of brain) is supplied by **small vessels** (e.g. lenticulostriate arteries) ↔ most common cause odf dementia is chronic **small vessel** disease

Answer 269

* **NO** underlying cause * common types: 1. MIGRAINE: **most common**, often in **females**; **unilateral**; associated with nausea and vomiting, **photophobia, phonophobia, aura** 2. TENSION: **bilateral**; **tight band** around head 3. CLUSTER: affects **males** more; associated with **IPSILATERAL autonomic** symptoms (e.g. tearing, nasal congestion, ptosis, miosis) ## Footnote miosis = **CONSTRICTED** pupil while mydriasis = dilated pupil

Answer 270

* **new onset** headache in **elderly** * accompanying features: 1. **temporal** tenderness / **jaw** claudication 2. associated with **polymyalgia rheumatica** * complications: **BILATERAL blindness** ## Footnote * jaw claudication = pain and fatigue in the jaw muscles during chewing, which resolves with rest * definitive test: temporal ARTERY biopsy * treatment: high dose **steroids**

Answer 271

autosomal dominant polycystic kidney disease (ADPKD)

Answer 272

* SAH * cerebral VENOUS sinus THROMBOSIS: may present with **seizures**; risk factors: **coagulation** disorders, **pregnancy**, **OCP**; diagnosis: CT/MR **venography** where **empty delta sign** is seen due to **filling defect** * carotid artery DISSECTION: may present with **tearing neck pain** and **Horner's** syndrome ## Footnote in this Horner's syndrome, NO anhidrosis

Answer 273

* anxiety: response to **ANTICIPATED threat** * GAD: **excessive, uncontrollable** worry which interferes w/ **daily functioning**, and is present for **at least 6 months**

Answer 274

* low dose: **anxiolytic** and **sedative** effects * high dose: **hypnotic** effects * even higher doses: **anaesthetic** effects ## Footnote * sedative = **relaxed** * hypnotic = **drowsy**, sleepy

Answer 275

* **positive** symptoms (= **added** abnormal stuff): delusions, hallucinations, ... * **negative** symptoms (= **subtracted** normal stuff): withdrawal from social interactions, flattening of emotional responses, ... * anxiety/depression * aggression * cognitive symptoms ## Footnote comparing positive vs negative symptoms, **(-)** symptoms are generally **more dominant**

Answer 276

flum**AZE***NIL* ("think of it as *NO MORE* benzodi**AZE**pines") * benzodiazepine receptor **antagonist**

Answer 277

"*T*o*M* the *LO*nely *CAT* from *DC F*ilms" * short acting: 1. *T*ri**azo**lam 2. *M*id**azo**lam * intermediate acting: 1. *L*or**aze**pam 2. *O*x**aze**pam 3. *C*lon**aze**pam 4. *A*lpr**azo**lam 5. *T*em**aze**pam * long acting: 1. *D*i**aze**pam 2. *C*hlorodi**aze**poroxide 3. *F*lur**aze**pam

Answer 278

* disturbed sleep * rebound anxiety * tremor/convulsions

Answer 279

**pentoxifylline** * MOA: 1. **platelet aggregation** AND reduce **blood viscocity** AND improve **deformability of RBCs** 2. non-selective **PDE** inhibitor and **adenosine 2** receptor antagonist → reduce **platelet adhesion and aggregation** AND prevent **vasoconstriction** + promote **vasodilation** ## Footnote ALL IN ALL they help to **improve blood flow**

Answer 280

ANTICOAGULANTS 1st — monotherapy using Direct Oral Anticoagulants (DOACs): * rivaro**xa**ban or api**xa**ban * Factor **Xa** inhibition → ↓ thrombin generation ⇒ prevents clot growth 2nd — when DOACs are not suitable: * **LMWH + warfain** OR **LMWH + dabigatran/edoxaban** ## Footnote * LMWH: activator of antithrombin III → inhibits Factor **Xa** * warfarin: **Vit K** antagonist → reduces Factors **II, VII, IX, X** * dabigatran: also a DOAC but works by directly inhibiting **thrombin (Factor IIa)**

Answer 281

* **carotid** body and sinus = CN **IX** * **aortic** body and sinus = CN **X**

Answer 282

**thoraco***dorsal* nerve "cos lats are at the *back* and are located more inferiorly, at the **thorax** rather than scapula"

Answer 283

*dorsal* **scapular** nerve "cos rhomboids are at the *back* and are located **bet the scapula**"

Answer 284

* **UV** exposure * **SMOKING**

Answer 285

"RASH OR PAIN" * Rash: butterfly (erythematous patches over cheeks and nose), **spares nasolabial folds** * Arthritis * Serositis: pericaritis, pleuritis * Haematological involvement: **anaemia**, cytopenia * Oral or nasal ulcers * Renal involvement: lupus **nephritis** * **Photosensitive** * Autoantibodies seen in investigations * Immune disorder * Neurological involvement: stroke, seizure | serositis = inflammation of serous membranes ## Footnote other conditions: ILD, oesophagitis

Answer 286

* **ESR** if wanna check for inflammation * sensitive: **ANA** specific: anti-**Smith**, anti-**dsDNA**

Answer 287

* conservative: **sun protection** * topical (for treatment of cutaneous only): corticosteroids, calcineurin inhibitors, retinoids * oral/systemic: **hydroxychloroquine**

Answer 288

deficiency of classical **complement** proteins (C1Q, C2, C4) -> loss of tolerance -> **autoantibody** production => antibody-antifen **immune complex** formation and **deposition** in microvasculature * deposition at **dermoepidermal junction**, resulting in **positive LUPUS band test** immune complex also results in complement activation => **inflammation** and tissue **injury** (including damage to vessel walls by neutrophils) * cutaneous small vessel vasculitis * leukocytoclastic vasculitis (due to said neutrophils then undergoing fragmentation) ## Footnote leukocytoclastic vasculitis: * suspect when there is **palpable purpura** * evaluare with **skin punch biopsy** and **immunofluorescence**

Answer 289

B) **"Full house" immunofluorescence** with IgG, IgA, IgM, C3, and C1q nephritic syndrome associated w/ SLE = **lupus nephritis**

Answer 290

* **structural** vascular abnormalities (e.g. **arteriovenous** malformations) * **HTN** → charcot bouchard MICROaneurysms ⇒ *single large* haematoma * various causes (e.g. **fat embolism**, malaria, vasculitis, acute hypertensive encephalopathy) → **petechial** haemorrhage ⇒ *multiple small "dot-like"* haemorrhages * cerebral **amyloid** angiopathy → amyloid proteins deposited on **walls** of blood vessels ⇒ predispose to bleeding

Answer 291

* tear in **MMA** ← trauma to pterion * **lens**-shaped / **biconvex** * lucid interval before deterioration

Answer 292

* tear in **bridging** veins ← **chronic**: **falls** in elderly **acute**: MAJOR **trauma** (e.g. acceleration-deceleration injuries) * **crescent**-shaped * **hyper**dense for acute, **hypo**dense for chronic

Answer 293

* **berry** aneurysm: majority is **anterior communicating artery**, but sometimes MCA * symptoms of **meningism** <- blood can irritate the meninges <- blood is in subarachnoid space and in contact w/ **pia mater**, which is packed w/ **sensory nerve endings** * **hyper**dense blood in **sulci** and **basal cisterns** * check for **xanthochromia** in **LP** **8h** after onset (or headache if have) * associated with **ADPKD** ## Footnote * don't check for RBCs ← presence cld be from trauma when performing LP * only after around 8h ← enough time for RBCs to lyse and release bilirubin and thus result in yellow discolouration of CSF (= xanthochromia)

Answer 294

* headache * **neck stiffness** * **photophobia** * (+) **Kernig** sign = pain when stretching meninges via straigtening leg from hip and knee flexion position * (+) **Brudzinski** sign = involuntary flexion of hips and knees upon passive neck flexion of a supine patient

Answer 295

ischaemia → decrease perfusion → cytotoxic **oedema** ⇒ brain tissue becomes **HYPOdense** and loses contrast bet structures * loss of grey-white differentiation * sulcal effacement * possible midline shift

Answer 296

* dense MCA sign: **HYPERdense** *thrombus* * loss of **insular** ribbon

Answer 297

* **HYPERdense** bright *ACUTE blood* * surrounding **HYPOdense** *oedema*

Answer 298

"*D*on't *W*orry, *I*t's just **A** **D**ark **C**loud" * *DWI*: bright * **ADC**: dark

Answer 299

"WHITE thrombi" * **rapid** turbulent flow in **ARTERIES** -> atherosclerotic **plaque ruptures** -> endothelial **damage** => **PLATELETS** recruited for rapid repair * treatment: antiplatelets (e.g. aspirin, clopidogrel, ticagrelor) "RED thrombi" * **slow** flow in **VEINS** (emboli commonly are too) -> stasis -> **clotting factors** accumulated -> **fibrin** formation => **RBCS** trapped by fibrin mesh * treatment: anticoagulants (e.g. DOAC, warfarin, LMWH)

Answer 300

affects INFERIOR part of **parietal** lobe AND whole **temporal** lobe * IF lesion occurs at **non-dominant** side => **hemineglect** = **ignoring** CONTRALATERAL side of body and space * Wernicke's **receptive aphasia** * **Meyer's** loop (= **inf** optic radiations) => CONTRALATERAL **superior quandrantopia** ## Footnote receptive aphasia presents w/ * poor comprehension * **fluent BUT nonsensical** speech * also poor repetition

Answer 301

affects **lateral** part of **frontal** lobe * Broca's **expressive aphasia** * **motor** cortex (specifically **face and arms** area) => face and arm **weakness** * **frontal eye field** => **gaze** preference **toward lesion** ## Footnote expressive aphasia presents w/ * good comprehension * **non-fluent, effortful** speech * poor repetition

Answer 302

affects **medial** part of **frontal** lobe AND **medial** part of **parietal** lobe * **motor** cortex (specifically lower limbs area) => leg > arm **weakness** AND urinary incontinence

Answer 303

1. determine if medial or lateral 2. determine which part of brainstem via CN affected 3. match to the artery

Answer 304

1. cerebral hemispheres, brainstem: **UMN** signs cerebellum: NO UMN signs, ONLY cerebellar signs (**DDASHING**) 2. cerebral hemispheres: **visual field defects** and *contralateral hemiparesis and/or sensory loss* brainstem: **ipsilateral CN deficits** (including **eye movement abnormalities**), **cerebellar** signs (vertigo and ataxia), **Horner** syndrome, impairment of loss of **consciousness** and *contralateral hemiparesis and/or sensory loss* 3. cortical (= involving grey matter): **higher cortical dysfunction** (e.g. affecting languge, awareness) ## Footnote * visual field defects = problem with **visual pathway** (usually optic radiation or occipital cortex) => patient sees **missing part of the world** * eye movement abnormalities = problem with nuclei **CNs III, IV, VI**, medial longitudinal fasciculus or gaze centers -> eyes **cannot align** tgt => **diplopia**

Answer 305

microscopic: * 12h: ischaemic neuronal change (**red neurons**, oedema) * <48h: **neutrophils** * 2d: **foamy** macrophages (microglia) * 1-3 weeks: even more macrophages + reactive **gliosis** (astrocytes) gross: * 48h: soft, **pale**, swollen * 2-10d: **gelatinous**, **friable** * 2-3 weeks: **liquid** filled **cavity** ## Footnote reactive gliosis is how the brain "heals": astrocytes around edge of hole starts to enlarge and proligerate => astrocytic scar

Answer 306

depression is associated w/ **deficiency or dysregulation** of monoamine neurotransmitters — **norepinephrine/noradrenaline**, **serotonin** (5-HT) and **dopamine** — in the CNS

Answer 307

* MAO breaks down **NOREPINEPHRINE, SEROTONIN and DOPAMINE** in **presynaptic** neuron "mouse eating NORTH COMPASS and SMILEY FACE cheese" "mouse biting through DOPAMINE rope" * MAOI is a **NON-SELECTIVE** and **IRREVERSIBLE** inhibitor of MAO "mouse trap KILLS ALL the mouses" -> increased conc of neurotransmitters in presynaptic neuron -> more neurotransmitters released into synaptic cleft => increased signaling

Answer 308

phenelzine

Answer 309

* postural hypotension * restlesness and insomnia

Answer 310

* MAOIs, SSRIs, SNRIs * neuromuscular **excitation**: tremors, clonus, hyperreflexia, myoclonus, rigidity * **autonomic** dysfunction: hyperthermia, tachycardia, diaphoresis, HTN * altered **mental** state: agitation, confuision, delirium ## Footnote think of an angry boss: he's agitated, red from anger and trembling and tapping his feet angrily

Answer 311

inhibit **PRESYNAPTIC** UPTAKE of **NOREPINEPHRINE** and **SEROTONIN** -> increased conc of neurotransmitters in synaptic cleft => increased signaling "Boy on tricycle hit by ball, and thus prevented from PICKING UP NORTH COMPASS and SMILEY FACE balls"

Answer 312

* sedation <- H1 **histamine** receptor **antagonism** "bee swatter" * *postural hypotension* <- **ALPHA-adrenoceptor** sympathetic **block** "ball hits girl holding a cake with an **ALPHA** flame, causing her to *fall down*" * *anticholinergic* side effects (e.g. dry mouth, blurred vision, constipation) <- **muscarinic** receptor **antagonism** "ball also hits and thus disrupts the *"Alice in wonderland"* party"

Answer 313

"amy has an im**print** on her face from the ball hitting her, which also caused her to *trip* over her tricycle" * imi**pr**am**ine**, desi**pra**m**ine** * ami*trip*tyline, nor*trip*tyline ## Footnote some are **selective for norepinephrine** transporter => **fewer** side effects * nortriptyline, desipramine while others are non-selective * AMI*trip*tyline, IMI**pr**am**ine** "AMY has an IM**print** on her face from the ball hitting her, which also caused her to *trip* over her tricycle"

Answer 314

inhibit **presynaptic** UPTAKE of **norepinephrine** and/or **serotonin** -> increased conc of neurotransmitters in synaptic cleft => increased signaling

Answer 315

* much greater 5-HT reuptake **selectivity** -> lack of **effect** at **histamine** receptors, low **affinity** for **a-adrenoceptors** and low **affinity** for **muscarinic** receptors => fewer of those **A/Es** ## Footnote **citalopram** still has some degree of **histamine** receptor antagonim => causes **sedation**

Answer 316

* **SEXUAL DYSFUNCTION**: delayed ejaculation, anorgasmia * *nausea* * *insomnia* "girl REJECTS EX, while one friend *watches on excitedly* and another *almost vomits* out of disgust"

Answer 317

"travel agency has posters, including one with the words "*Fly Out"* and another with the words "the **City**"" * *fluo*xetine * **cita**lopram

Answer 318

* (same as SSRIs) sexual dysfunction, insomnia and nausea * **withdrawal** effects: dizziness, nausea, headache, anxiety, etc

Answer 319

"the office has a *fax* machine and a **dual** copier/scanner machine" * venla*fax*ine * desvenla*fax*ine * **dulo**xetine

Answer 320

* e.g. **reboxetine** * all A/Es are due to increased NA resulting in increased sympathetic activity: tachycardia, insomnia, anticholinergic effects (e.g. dry mouth, constipation)

Answer 321

**D**2 **antagonism** <- dopamine is increased in acute schizophrenia

Answer 322

"VAN GOGH's painting about star g**azing**, which has a moon *halo* in it" * chlorprom**azine** * fluphen**azine** * trifluoper**azine** * *halo*peridol

Answer 323

"MODERN art gallery with a sign stating "quiet please, *only* **whispering** is appropriate"" * *olan*zapine * **risperi**done "MODERN art gallery also has a *closet* as an artpiece" * *cloza*pine just remember lol * amisulpride

Answer 324

LESS **extra**pyramidal symptoms (EPS) due to * lower D2 receptor **occupancy** in striatum at therapeutic doses * concurrent **antagonism** of **serotonin** 5-HT2A receptors -> **modulate *dopamine* release** in striatum "MODERN art gallery has *smiley face* cheese being cut up and served to guests" ## Footnote *nigo***striatal** pathway: * DOPAMINE pathway involved in MOVEMENT CONTROL * involves both *substantia nigra* and **striatum** * has serotonin acting as an inhibitor of dopamine release in striatum

Answer 325

* reversible: acute **dystonia** = **parkinsonism**-like symptoms (cogwheel rigidity, resting tremor) * irreversible: 1. tardive **dyskinesia** = repetitive and stereotyped **involuntary** movements of **face, tongue** and limbs 2. **akathisia** = **involuntary** movements and **compulsion** to act associated w/ **restlessness, anxiety and agitation**

Answer 326

* sedation (esp in C & O), postural hypotension and reflex tachycardia (esp in R) and anticholinergic side effects (e.g. dry mouth) (esp in C & O) <= **HAM** antagonism * *hyperglycaemia*, *diabetes* and **weight gain** (C, O & R) "painting of a **fat** face and *all the candies he's eating*" * clozapine only: **AGRANULOCYTOSIS** "FALLING GRANULES within hourglass in painting in closet" * **amisulpride** only: (females) breast swelling, lactation, pain (males) **gynaecomastia** <= increase in **prolactin**

Answer 327

* *mars*-tazapine: *NASA* (NorAdrenaline and **Serotonin** antidepressant) * buproprion: noradrenaline and **dopamine** reuptake inhibitor * agomelatine: **agonist** of **melatonin** MT1 and MT2 receptors * vortioxetine: pro-cognitive effects but also **increased risk of suicidal thoughts or actions**

Answer 328

* communicating = no obstruction in flow of CSF => should be due to disturbance to** formation** or **absorption** of CSF (e.g. meningitis causing **scarring** and thus ventricular outflow obstruction, SAH **blocking arachnoid villi**) * non-communicating = obstruction in **flow** of CSF **WITHIN ventricles** (e.g. congenital malformations like Arnold Chiari malformation)

Answer 329

* nausea and vomiting * headache which is **worse**: 1. when **waking up** in the morning 2. on **lying down** 3. on **bending over** 4. on **coughing/sneezing/straining**/valsalva * **papilloedema** on **fundoscopy** ## Footnote papilloedema is NOT associated w/ increased cup disc ratio (trick qn!)

Answer 330

* cranial nerve palsies: CN **VI** is MOST vulnerable * Cushing's triad: abnormal **B**P (widened pulse pressure), **B**radycardia and abnormal **B**reathing (irregular respiration) * LOC * WORST! => cerebral **herniation** ## Footnote cerebral herniation results in **haemorrhage** and **necrosis** of affected area, compression and infarction of **artery** there, compression of **cranial nerves** there and **DEATH**

Answer 331

**tonsillar** herniation <- compression of **cardiorespiratory** vital centres in brainstem

Answer 332

* leptomeningeal ENHANCEMENT due to infection -> inflammation -> **exudate** => **thickening** and enhancement of meninges * EFFACEMENT (= narrowing) of sulci and basal cisterns * (TB and bacterial) ventricular enlargement (mild) due to **thick inflammator exudate** -> block CSF flow => obstructive **hydrocephalus**

Answer 333

* 1st line: NON-CONTRAST **CT** => to check for **haemorrhage** * if haemorrhage is ruled out: **CT** angiogram (w/ CONTRAST) => identify location of clot * later: **MRI** (DWI/ADC) => gold-standard for accuracy and detail ## Footnote * don't use contrast initially as BOTH fresh blood and contrast looks bright white on imaging -> unable to differentiate

Answer 334

both are **localised** collections of **pus** * empyema: **"outside"** brain parenchyma, **pressing in** * cerebral abscess: **within** brain parenchyma

Answer 335

* (majority!) **subdural**: 1) due to **infection** of paranasal **sinus** 2) could result in **thrombophlebitis** of **bridging** veins => **infarction** of **brain** * **epidural**: 1) associated w/ **osteomyelitis** where **local infection** (e.g. sinusitis) -> osteomyelitis of bone -> pus breaks through bone => epidural abscess 2) can result in **spinal cord** epidrual infection => cord **compression** ## Footnote * thrombophlebitis = inflammation of vein which then leads to a clot -> venous congestion -> increased pressure in veins and thus in capillaries => blood cannot enter brain tissue cos of high pressure

Answer 336

* most commonly caused by **bacteria**, esp **Streptococcus** and **Staphylococcus aureus** * imaging: **capsule** seen in later stage of development ## Footnote Strep does NOT refer to strep pneumoniae or meningitides, but rather strep **viridans**, strep anginosus or strep intermedius

Answer 337

* **imaging**: 1) **CT** (**non-contrast** first) 2) MRI * obtain **CSF** via **lumbar puncture** and carry out a CSF **examination**: 1) appearance: **cloudy** = **meningitis** 2) cytology: increased **polymorphs** = bacterial increased **lymphocytes** = viral 3) biochemistry: **low glucose** = **bacterial** or **fungal** normal = viral 4) microbiology: send for PCR and culture * if LP cannot be done, do **blood culture** ## Footnote * **imaging** must be done FIRST -> checks for pathologies which can cause **raised ICP** (e.g. haemorrhages, ischaemia) => if raised ICP, then **cannot do LP**

Answer 338

**folate** deficiency bcos neural tube closure requires rapid DNA synthesis ← rapid purine and pyrimidine synthesis ⇐ requires a lot of folate

Answer 339

**"10 + 9 = ?"** * chromosome **19** * chromosome **21**

Answer 340

* histo: abnormal **protein deposition** in brain, including 1) **amyloid** plaques OUTSIDE neurons 2) **neurofibrillary tangles** = hyperphosphorylated **tau** protein WITHIN neurons * gross: 1) diffuse **cortical ATROPHY** , esp at **temporal** lobe 2) shrunken gyri and prominent sulci ## Footnote note: since BOTH AD and HSV1 encephalitis affect **temporal** lobe (which is where limbic structures like **hippocampus** and amygdala sit), they both present w/ **anterograde amnesia** (= inability to form new memories), just that AD is more progressive while HSV1 **encephalitis** is **acute and severe**

Answer 341

* acute: **Wernicke** encephalopathy where vit B1 is **co-factor** for several **enzymes in glucose metabolism**, -> **unable to use glucose** despite sufficient glucose -> acute neuronal energy failure => LESIONS in areas w/ **high metabolic requirements** presents w/ triad: **opthalmoplegia**, **ataxia**, confusion * chronic: **Korsakoff's** syndrome: chronic NECROSIS and GLIOSIS of areas crucial for **memory formation**, presents with **anterograde** AND **retrograde amnesia**, **confabulation**

Answer 342

* histo: mutation of **a-synuclein** protein, resulting in 1) **Lewy bodies** (= accumulation of a-synuclein) IN neurons 2) **pallor** in **SUBSTANTIA NIGRA**

Answer 343

* **infarct** in **ANTERIOR spinal** artery * affects **spinothalamic** tracts (ventral and lateral) => loss of **pain + temp** below lesion * also affects **corticosoinal** tracts (ventral and lateral) => bilateral **motor weakness**

Answer 344

* vit **B12** deficiency -> failure of **myelin synthesis** => demyelination of nerve fibres (esp longer ones), tabes dorsalis (**neurosyphilis**) => **damage** to nerve fibres, either directly or through inflammatory response * affects **DCML** => loss of **vibration + proprioception** below lesion ## Footnote loss of proprioception => **sensory** ataxia * presents w/ **instability** that worsens when eyes are closed — (+) **Romberg** test * diff from cerebellar ataxia, which presents w/ **incoordination**

Answer 345

* **L**MN signs <- collection of **nerve roots** that extend below the spinal cord * **asymmetric** leg weakness * **saddle** *anaesthesia*: S3-S5, *loss of sensation* in **buttocks, perineum and inner thighs** * **urinary retention** and/or overflow incontinence AND poor **anal (sphincter) tone**: S2-S4

mskderm 2 Flashcards

(387 cards)