12.3

Question 1

Name the common flexor origin (forearm muscles)

Answer 1

Medial epicondyle

Question 2

Name the common extensor origin (forearm muscles)

Answer 2

Lateral epicondyle

Question 3

The flexor forearm compartment (anterior compartment generally) is composed of 8 muscles. List them all.

Answer 3

2 pronators of forearm (pronator teres + quadrates)

2 long flexors of fingers (flexor digitorum superficialis + flexor digitorum profundus)

1 long flexor of thumb (flexor pollicis longus)

2 flexors of wrist (flexor carpi radialis + flexor carpi ulnaris)

1 long muscle of palm (palmaris longus - vestigial in humans + absent in 10-15% of population)

Question 4

Most flexor muscles of forearm are innervated by median nerve.

Which are innervated by ulnar nerve?

Answer 4

Flexor carpi ulnaris

Medial part of flexor digitorum profundus

Question 5

Which is deeper - pronator quadratus or pronator teres?

Answer 5

Pronator quadratus

Question 6

Which type of forearm muscles are anterior and medial?

Answer 6

Flexor muscles

Question 7

Which type of forearm muscles are posterior and lateral?

Answer 7

Extensor muscles

Question 8

How many extensor muscles of the foerarm are there?

Answer 8

12 - all supplied by radial nerve

Question 9

Which forearm muscle is responsible for supination?

Answer 9

Supinator;

The biceps is also a supinator..

Question 10

Why is the brachioradialis muscle unusual?

Answer 10

Lies in posterior compartment of forearm but is a weak flexor at elbow but still supplied by radial nerveIt lies on thumb side.

Question 11

How many tendons pass through the carpal tunnel?

Answer 11

9 flexor tendons

Question 12

Which nerve passess between the tendons of flexor digitorum profundus and superficialis?

Answer 12

Median nerve

Question 13

List the main contents of the anatomical snuffbox?

Answer 13

Radial artery

Radial nerve branch

Cephalic vein

Question 14

What is carpal tunnel syndrome?

Answer 14

o Conditions that cause swelling (e.g. arthritis, pregnancy, oedema) can lead to median nerve compression as it passes through the carpal tunnel

o This leads to loss of sensation in the hand in region supplied by median nerve + reduced movement of the thumb as the median nerve supplies the muscles of the thumb

Question 15

Name 2 tests for carpal tunnel syndrome.

Answer 15

 Tinel’s sign – tapping the nerve in carpal tunnel to elicit pain in median nerve distribution

 Phalen’s manoeuvre – holding the wrist in flexion for 60 seconds to elicit numbness/pain in median nerve distribution

Question 16

What is finger abduction?

Answer 16

When fingers move away from middle finger

Question 17

Name all the carpal bones in the proximal row from lateral to medial from anterior view.

Answer 17

• Scaphoid – has tubercle on lateral, palmar surface
• Lunate – dislocates uncommonly but have severe morbidity associated with them if the diagnosis is delayed
• Triquetrum
• Pisiform – can be felt

Question 18

List all the carpal bones in the distal row from lateral to medial from anterior view.

Answer 18

• Trapezium – has tubercle on palmar surface
• Trapezoid
• Capitate – largest carpal bone
• Hamate – has hook on palmar surface

Question 19

A single synovial sheath surrounds 8 of the 9 flexor tendons. Which tendon is surrounded by its own synovial sheath?

Answer 19

Flexor pollicis longus (flexor digitorum profundus and superficialis have 4 tendons each and around surrounded by the single synovial sheath)

Question 20

Bennett’s fracture

Answer 20

• Fracture of the 1st metacarpal base
• Extending into the carpometacarpal joint
• Caused by hyperabduction of the thumb

Question 21

Boxer’s fracture

Answer 21

• Fracture of 5th metacarpal neck
• Usually caused by a clenched fist striking a hard object
• Distal part of fracture is displaced posteriorly, producing shortening of affected finger

Question 22

Metacarpal I is related to the thumb. What is the 3rd metacarpal related to?

Answer 22

Middle finger

Question 23

Dorsal venous network of hand is a network of veins in superficial fascia on dorsum of hand formed by dorsal metacarpal veins.

Where are they found and what do they give rise to?

Answer 23

Found on back of the hand and give rise to cephalic and basilic veins

Question 24

Which digits are affected by an ulnar nerve lesion at the wrist at rest?

Answer 24

Digits 4 and 5

Question 25

Which digits are affected by a median nerve lesion at wrist or elbow when attempting to make a fist?

Answer 25

Digits 2 and 3. Only digits 4 and 5 flex

Question 26

List 4 common fracture sites.

Answer 26

 Distal radius  Vertebra  Proximal femur  Proximal humerus

Question 27

Function of deep fascia

Answer 27

o Covers muscles + helps divide the muscular sections into compartments – which work in functional units o Fascia prevent the contracting muscles from causing friction in the subcutaneous fat/dermis above as it’s a smooth barrier o Deep fascia does not stretch --> when muscles work (especially in distal LL) the pressure they cause to increase in size within the compartment helps w/ venous return – muscular venous pump

Question 28

Which property of deep fascia is what leads to compartment syndrome?

Answer 28

Deep fascia does not stretch --> when muscles work (especially in distal LL) the pressure they cause to increase in size within the compartment helps w/ venous return – muscular venous pump

Question 29

Muscles that make up quadratus femoris

Answer 29

o Rectus femoris o Vastus lateralis o Vastus intermedius o Vastus medialis

Question 30

Which compartment are the following muscles a part of? - Sartorius - Pectineus - Iliopsoas - Quadratus femoris

Answer 30

Anterior thigh compartment

Question 31

Which compartment do the following muscles belong to? - Adductor brevis - Adductor longus - Adductor magnus* - Gracilis - Obturator externus

Answer 31

Medial thigh compartment

Question 32

Which compartment do the following relate to? - Obturator nerve (L2-L4 ant) - Obturator artery - Adduction of hip

Answer 32

Medial thigh compartment

Question 33

Which compartment do the following relate to? - Femoral nerve (L2-L4 post) - Femoral artery - Extension of knee + Flexion of hip

Answer 33

Anterior thigh compartment

Question 34

Which compartment do the following relate to? - Sciatic nerve (L4-S3) - Profunda femoris + perforating arteries - Extension of hip + Flexion of knee

Answer 34

Posterior thigh compartment

Question 35

Which compartment do the following muscles belong to? - Biceps femoris - Semitendinosus - Semimembranosus

Answer 35

Posterior thigh compartment

Question 36

Which compartment do the following muscles belong to? - Tibial anterior - Extensor digitorum longus - Extensor hallucis longus - Fibularis tertinus

Answer 36

Anterior leg compartment

Question 37

Which compartment do the following relate to? - Deep fibular nerve - Anterior tibial artery - Dorsiflex ankle (L4, L5) - Bound by extensor retinacula

Answer 37

Anterior leg compartment

Question 38

Which compartment do the following relate to? - Superficial fibular nerve - Fibular artery* - Evert ankle (L5, S1)

Answer 38

Lateral leg compartment

Question 39

Which compartment do the following muscles belong to? - Fibularis longus - Fibularis brevis

Answer 39

Lateral leg compartment

Question 40

``` Which compartment do the following muscles belong to? Superficial group: o Gastrocnemius o Plantaris o Soleus ``` ``` Deep group: o Popliteus o Tibialis posterior o Flexor digitorum longus o Flexor hallucis longus ```

Answer 40

Posterior leg compartment

Question 41

Which compartment do the following relate to? - Tibial nerve - Posterior tibial artery - Plantar flexors (S1, S2)

Answer 41

Posterior leg compartment

Question 42

The lumbar plexus is formed by the anterior primary rami of which spinal roots?

Answer 42

L1-4

Question 43

Where does the trunks of the lumbar plexus lie within?

Answer 43

Substance of psoas major

Question 44

Name the 6 major peripheral nerves which branch from the lumbar plexus.

Answer 44

``` o Iliohypogastric o Ilioinguinal o Genitofemoral o Lateral cutaneous of thigh o Obturator o Femoral ```

Question 45

I, I Get Love On Fridays What is this a mnemonic for?

Answer 45

Lumbar plexus branches ``` o Iliohypogastric o Ilioinguinal o Genitofemoral o Lateral cutaneous of thigh o Obturator o Femoral ``` *H comes before I so ilioHypogastric is before ilioInguinal

Question 46

Which plexus is formed by the anterior primary rami of S1-4 (with contributions from L4 + 5)?

Answer 46

Sacral plexus

Question 47

List the 5 major branches of sacral plexus.

Answer 47

``` o Superior gluteal nerve o Inferior gluteal nerve o Sciatic nerve o Posterior femoral cutaneous o Pudendal nerve ```

Question 48

When injecting into the gluteal region, which quadrant should you go for?

Answer 48

Upper lateral quadrant Medial upper and lower quadrants is bad because of the superior gluteal nerve Lateral inferior quadrant - there's a greater chance of hitting sciatic nerve

Question 49

Name the line on the posterior surface of the femoral shaft

Answer 49

Linea aspera

Question 50

Where is the pectineal line?

Answer 50

Proximally, on the medial border of linea aspera becomes pectineal line

Question 51

What can a neck of the femur fracture cause?

Answer 51

 Shortened limb  Externally rotated limb (iliopsoas axis of action)  Torn retinacular arteries --> risk of avascular necrosis

Question 52

Are intra- or extra- capsular fractures more common in elderly people?

Answer 52

Intra  They are result of minor trip or stumble  Facture occurs within capsule of hip joint  Can damage medical femoral artery which causes avascular necrosis of femoral head

Question 53

Neck of fracture causes external or internal rotation?

Answer 53

External And leg is shortened With a dislocation leg is shorted and medially rotated

Question 54

Where are osteogenic cells located?What do they develop into?

Answer 54

In inner layer of periosteum and endosteum Develops into an osteoblast

Question 55

What are bisphosphonates?

Answer 55

o Inhibit mineralisation or bone resorption by inhibiting osteoclasts o Bisphosphonates are enzyme-resistant analogues of pyrphosphoric acid, which norammly inhibits mineralisation in the bone

Question 56

MoA of bisphosphonates used in the inhibition of bone resorption.

Answer 56

 BPs attach to hydroxyapatite binding sites in bone  They are a prodrug • Action of osteoclast forming sealing zone releases bisphosphonate, this is taken up by osteoclasts  When osteoclasts resorb bone impregnated w/ BP, BP released during resorption impairs ability of osteoclasts to: • Form the ruffled border • Adhere to the bony surface • Produce the protons for bone resorption  BPs decrease osteoclast activity by decreasing osteoclast progenitor development + recruitment + increasing osteoclast apoptosis

Question 57

SE of bisphosphonates.

Answer 57

 Osteonecrosis of the jaw bone is the widest adverse effect of BP therapy  There is an increased risk of osteonecrosis of jaw bone due to: • Poor oral hygiene • Invasive dental procedures • Prolonged exposure to high doses of IV bisphosphonates

Question 58

Calcitonin moa

Answer 58

o Another pharmacological approach is trying to modulate the calcitonin/PTH levels to control calcium o Calcitonin is secreted by thyroid gland when blood calcium level increases:  Decreases blood calcium levels  Stimulates calcium deposition in bones  Reduces calcium uptake in kidneys

Question 59

PTH is secreted by parathyroid gland when blood calcium level decreases. What does it do?

Answer 59

 Increases blood calcium levels  Stimulates calcium release from bones  Increases calcium uptake in kidneys  Increases calcium uptake in intestines  Must be careful about dosage of PTH: • Low dose – increases osteoblast activity – desired result • High dose – increases bone reabsorption + thins bone

Question 60

Why does steroids need to be withdrawn slowly?

Answer 60

• Adrenal gland starts to shrink + reduces steroid production significantly when steroids used long term. o So steroids need to be withdrawn slowly, so steroid production increases overtime o If steroid treatment abruptly stopped --> atorpy

Question 61

What are DMARDs?

Answer 61

Drugs used for other conditions but at low doses help w/ RA. Disease-modifying antirheumatic drugs

Question 62

Effects of DMARDs?

Answer 62

* Slow down disease progression * Reduce damage to the joints * Usually taken for rest of life * They suppress body’s overactive immune systems * Need to have regular blood tests, to see if DMARDs are having any side effects * But serious side-effects affecting the blood, liver, or kidneys (rare)

Question 63

What is synovial membrane?

Answer 63

Specialised connective tissue that lines inner surface of capsules of synovial joints + tendon sheath

Question 64

Function of synovial membrane?

Answer 64

 It makes direct contact w/ synovial fluid lubricant  It is primarily responsible for maintaining synovial fluid lubricant

Question 65

At tissue surface, there are many rounded macrophage-like synovial cells (type A) + fibroblast-like (type B) synovial cells. What are the functions of A and B type cells?

Answer 65

 Type A cells – maintain synovial fluid by removing wear-and-tear debris by phagocytosis  Type B cells – secrete hyaluronic acid + protein complex (mucin) of synovial fluid

Question 66

What is cartilage?

Answer 66

A smooth elastic tissue that covers + protects the ends of long bones at the jointsIt’s a structural component of the rib cage, ear, nose, bronchial tubules, intervertebral discs, other body component

Question 67

Name 3 types of cartilage.

Answer 67

 Elastic – provides strength, elasticity, maintains shape  Hyaline – weakest cartilage found on many joint surfaces, precursor of bone  Fibrous – strongest cartilage, alternating layers of hyaline + collagen

Question 68

Pick the most appropriate synovial joint.Permits movement in several axis; a rounded head fits into a concavity (glenohumeral joint) ```  Hinge  Saddle  Plane  Pivot  Condyloid  Ball and socket ```

Answer 68

Ball and socket

Question 69

Pick the most appropriate synovial joint.Permits flexion and extension (elbow joint) ```  Hinge  Saddle  Plane  Pivot  Condyloid  Ball and socket ```

Answer 69

Hinge

Question 70

Pick the most appropriate synovial joint.Concave and convex joint surfaces unite at this joints (metatarsophalangeal joint) ```  Hinge  Saddle  Plane  Pivot  Condyloid  Ball and socket ```

Answer 70

Saddle

Question 71

Pick the most appropriate synovial joint.Permit gliding/sliding movements (acromioclavicular joint) ```  Hinge  Saddle  Plane  Pivot  Condyloid  Ball and socket ```

Answer 71

Plane

Question 72

Pick the most appropriate synovial joint.Allows rotation; a round bony process fits into a bony ligamentous socket (atlantoaxial, proximal radio-ulnar) ```  Hinge  Saddle  Plane  Pivot  Condyloid  Ball and socket ```

Answer 72

Pivot

Question 73

Pick the most appropriate synovial joint.Permits flexion, extension, adduction, abduction, circumduction (metacarpophalangeal joint) ```  Hinge  Saddle  Plane  Pivot  Condyloid  Ball and socket ```

Answer 73

Condyloid

Question 74

Other than synovial joints, name 3 types of joints.

Answer 74

Fibrous Primary cartilaginous (synchondrosis) Secondary cartilaginous (symphyses)

Question 75

Define rheumatoid arthritis

Answer 75

Long lasting autoimmune disorder that primarily affects joints RA = chronic, symmetrical, inflammatory, deforming, polyarthritis

Question 76

Signs and symptoms of RA

Answer 76

o Insidious onset (gradual)o Joint swelling – inflammatory arthritis o MCPs, MTPs, wrists commonly affected o Classically symmetrical in terms of affected joints o Early morning stiffness – joints stiffen when not used o Responds well to NSAID

Question 77

List the 3 stages of progression of RA

Answer 77

 Initiation phase – non-specific inflammation  Amplification phase – T-cell activation  Chronic inflammatory phase – tissue injury due to cytokines IL-1, TNF-alpha, IL-6

Question 78

What can trigger RA?

Answer 78

An external trigger (e.g. infection, trauma, smoking) sets of an autoimmune reaction (perhaps in genetically susceptible individuals)

Question 79

What does T cell stimulation in RA activate and result in?

Answer 79

* Activates macrophages, fibroblasts, B cells | * Result of this activation = production of whole range of cytokines

Question 80

What is detected in blood tests for RA?

Answer 80

B cells produce RF and anti-CCP antibody which is detected in blood test

Question 81

List the 3 main cytokines involved in RA

Answer 81

* TNF-alpha – main cytokine involved * IL-1 * IL-6

Question 82

How can inflammation cause joint damage in RA?

Answer 82

o The inflammation happens within the synovial layer o This gets organised together + starts to invade the adjacent cartilage (this is termed invading mass pannus)  Invading mass pannus – organised synovial cells which are invading + attacking the cartilage + bone o The cartilage + bone start to break down – this can be seen on an x-ray as joint space narrowing (cartilage degradation)o Bone erosion can be seen as punched out areas on x-ray

Question 83

List 5 consequences of chronic systemic inflammation in RA

Answer 83

o Early ischaemic heart disease (leading cause of mortality in RA) o Sarcopenia (damage to muscles w/ inflammation) - muscles become damaged + atrophied (thus not as strong) o Pain sensation can increase - unusual effects on pain sensitizer + nerve endings --> more susceptible for chronic pain o Osteoporosis - in patients w/ lots of inflammation o Insulin resistance + metabolic syndrome o Dementia

Question 84

Inflammatory markers are used to predict the prognosis of RA.List some erosion (bone) prognostic factors

Answer 84

Common prognostic factors: smoke status, RF, anti-CCP, ESR, CRP

Question 85

Inflammatory markers are used to predict the prognosis of RA.List some disability prognostic factors

Answer 85

Specific HLA antigen implicated, RF, anti-CCP

Question 86

Inflammatory markers are used to predict the prognosis of RA.List some mortality prognostic factors

Answer 86

Specific HLA antigen implicated, RF, anti-CCP

Question 87

RA summary

Answer 87

 Synovial inflammation  Genetic + environmental factors  Articular + extra-articular complications  Morbidity + mortality associated with the disease  Early assessment + diagnosis is essential  Treat inflammation early + aggressively  Established severe RA is bad  MDT approach needed  RA = chronic, symmetrical, inflammatory, deforming, polyarthritis

Question 88

Action of TNF-alpha

Answer 88

T lymphocyte + macrophage o Increases pro-inflammatory cytokines + chemokines (IL-1, IL-6, IL-8) -> increased inflammation o Increased adhesion molecules --> increased cell infiltration (affects vascular lining) Endothelium o Increased vascular endothelial growth factor  increased angiogenesis Hepatocyte o Increased acute phase response  increased CRP in serum (used in RA blood tests)Epidermis o Increased keratinocyte hyperproliferation  skin plaques Synoviocytes o Increased metalloproteinase syntheses  causes articular cartilage degradation

Question 89

What is the most common joint disorder/disease that results from breakdown of joint cartilage + underlying bone?

Answer 89

OA (osteoarthritis)

Question 90

Which joints does OA affect?

Answer 90

 Distal interphalangeal joints (DIP)  Proximal interphalangeal joints (PIP)  Carpometacarpal joints  Metatarsophalangeal joints  Axial skeleton  Large weight bearing joints

Question 91

Symptoms of OA

Answer 91

 Tend to come with activity + get better w/ rest  Little inflammation present – repair causes inflammation (wear, tear, repair)

Question 92

What is anti-CCP?

Answer 92

Anti-cyclic citrullinated peptide (anti-CCP) is an antibody present in most rheumatoid arthritis patients. Levels of anti-CCP can be detected in a patient through a blood test. A positive anti-CCP test result can be used in conjunction with other blood tests, imaging tests, and physical examinations to reach a rheumatoid arthritis diagnosis.

Question 93

Bouchard’s nodes

Answer 93

PIP joints – bony outgrowths or gelatinous cysts form

Question 94

Heberden’s nodes

Answer 94

DIP joints – bony swellings form

Question 95

List all the causes of pain in OA

Answer 95

o Prostaglandins o Cytokineso Synovitis o Subchondral fractures o Periosteal elevation o Muscle spasm o Venous congestion o Biomechanical effects

Question 96

Does RA or OA have an earlier onset?

Answer 96

RA (20-40) whereas OA is >50

Question 97

What is gout?

Answer 97

A form of inflammatory arthritis characterised by recurrent attacks of red, tender, hot, swollen joints

Question 98

What is the most common type of inflammatory arthritis in young men?

Answer 98

o Gout is the most common type of inflammatory arthritis in young men o It affects 1-2% of adult population o Prevalence increases w/ age

Question 99

Co-morbidities in gout

Answer 99

o Renal impairment typically (cannot excrete uric acid) o Coronary heart disease o Metabolic syndrome – obesity, dyslipidaemia, hypertension, type II diabetes

Question 100

Modifiable risk factors of gout

Answer 100

 Hyperuricemia  Diet – seafood, purines (metabolised to uric acid), red meat, beer  Alcohol consumption  Obesity  Certain drugs – low dose aspirin, thiazide diuretics, furosemide, cyclosporine, levodopa, nictonic acid

Question 101

Which foods/drinks should be avoided in gout?

Answer 101

Products with high purine Seafood, beer, red meat

Question 102

Not everyone w/ high levels of uric acid get gout, usually there is a trigger event --> mobilise uric acid in blood. List some triggers.

Answer 102

* Direct trauma * Intercurrent illness/surgery the triggers an acute phase response * Dehydration/acidosis – including alcoholic binge * Rapid weight loss

Question 103

Summaries gout

Answer 103

o Common metabolic disorder, increasing in incidenceo Associated w/ high-purine diet + high alcohol intake o Hyperuricemia is the cause of gout o Attacks caused by deposition of urate crystals in joints, resulting in inflammation o Gout is a recurrent + progressive condition. Eventually leading to advanced tophaceous gout o Identification of crystals in joint or tophus aspirate, allows a definitive diagnosis o Primary care, clinical diagnosis is reasonable accurate for typical presentations (wo/ aspirate)

Question 104

What is septic arthritis?

Answer 104

Acute swollen joint presentation, think infective arthritis o Especially if it’s a single joint or there’s a risk factor e.g. IV drug users o They may be presenting w/ sepsis

Question 105

How to confirm septic arthritis?

Answer 105

- Aspirate + confirm - Choose appropriate antibiotic based on gram status + species if it’s septic arthritis - Septic arthritis can mimic other things like acute gout, treat sepsis w/ broad spec antibiotics if suspicious, wait for results (?gout) - Duration of antibiotics in confirmed case can be difficult

Question 106

What is bursitis?

Answer 106

o Inflammation of one or more bursae (small sacs) of synovial fluid in the body o They are lined w/ synovial membrane that secretes a lubricating synovial fluid o When bursitis occurs, movement relying on the inflamed bursa becomes difficult + painful o Moreover, movement of tendons = muscles over the inflamed bursa aggravates its inflammation

Question 107

What is tenosynovitis?

Answer 107

o Inflammation of the synovium that surrounds a tendon o Symptoms include pain, swelling + difficulty moving the particular joint where the inflammation occurs o Tenosynovitis most commonly results from the introduction of bacteria into a sheath through a small penetrating wound such as that made by the point of a needle or thorn

Question 108

List the 5 big complementary therapies.

Answer 108

Acupuncture:  Fine needles are inserted at certain sites in the body for therapeutic or preventative purposes Osteopathy:  Moving, stretching and massaging a person’s muscles + joints Chiropractic:  Spinal manipulation which aims to treat ‘vertebral subluxations’ which are claimed to put pressure on nervesHerbal medicine  Medicines with active ingredients made from plant partsHomeopathy  Based on use of highly diluted substances (H2O) which practitioners claim can cause body to heal itself

Question 109

List assessment tools for pain.

Answer 109

o Visual analogue score o Verbal rating score o Brief pain inventory o HAD score – Hospital anxiety + depression scale o McGill pain score – Self-report questionnaire that allows individuals to describe quality + intensity of their pain to S-LANSS score – Aims to identify pain of neuropathic origin, as distinct from nociceptive pain, wo/ clinical examination

Question 110

List factors that lower pain threshold

Answer 110

- Discomfort - Insomnia - Fatigue - Anxiety - Fear - Sadness - Depression - Boredom - Introversion - Mental isolation - Social abandonment

Question 111

List factors that raise pain threshold

Answer 111

- Relief of symptoms - Sleep - Rest - Empathy - Companionship - Diversional activity - Reduction in anxiety - Elevation of mood - Analgesics - Anxiolytics - Antidepressants

Question 112

Neurovasculature of knee joint

Answer 112

o Vasculature: genicular anastomoss (supplied by genicular branches of femoral + popliteal arteries) o Innervation: femoral, tibial, common fibular nerves

Question 113

Where do collateral ligaments of the knee attach?

Answer 113

Medial and lateral epicondyles

Question 114

What is the intercondylar fossa?

Answer 114

Depression found on posterior surface of femurLies between 2 condyles and contains 2 facets for attachment of internal knee ligaments (cruciate)

Question 115

What is the tibial plateau (proximal) formed by?

Answer 115

Formed by the lateral + medial condyles

Question 116

What does the knee capsule contain?

Answer 116

Patella, ligaments, menisci, bursa

Question 117

What is menisci?

Answer 117

The medial + lateral menisci are fibrocartilage structures in the knee that serve 2 functions: o Deepen the articular surface of the tibia, thus increasing stability of joint o Act as shock absorbers Hence increase stability + weight distribution They are avascular

Question 118

What shape is the medial meniscus?

Answer 118

C (crescent shaped)

Question 119

What shape is the lateral meniscus?

Answer 119

O (oval shaped)

Question 120

Which meniscus is attached to MCL?

Answer 120

Medial

Question 121

Which meniscus is attached to popliteus tendon?

Answer 121

Lateral

Question 122

Is the medial and lateral menisci fixed of mobile?

Answer 122

Medial = fixed Lateral = free from LCL hence mobile

Question 123

What is the function of bursae?

Answer 123

* Synovial filled sac found between moving structures in a joint * Function = reduce wear + tear on structures

Question 124

Name the 4 bursa found in knee joint.

Answer 124

o Suprapatellar bursa, o Prepatellar bursa, o Infrapatellar bursa, o Semimembranosus bursa

Question 125

Ligaments of knee joint

Answer 125

o Tibial collateral ligament resists medial displacement  Assisted by the sartorius, semitendinosus, gracilis  Aided by the quadriceps femoris o The fibular collateral ligament resists lateral displacement  Assisted by the iliotibial tract  Aided by the quadriceps femoris o The cruciate ligaments prevent hyperextension by becoming taut

Question 126

Function of quadratus femoris in knee stabilisation.

Answer 126

The quadriceps femoris prevents anterior dislocation when the knee is flexed

Question 127

Axial rotation of leg is limited due to what?

Answer 127

o The intercondylar eminence of the tibia lodging in the intercondylar notch of the femur forming the pivot o The cruciate and collateral ligaments

Question 128

Which nerve innervates quadriceps muscles?

Answer 128

Femoral nerve (L2-L4)

Question 129

Function of iliotibial band

Answer 129

Pulls knee into hyperextension

Question 130

What is the iliotibial band?

Answer 130

o It is a thickening of fascia lata + provides lateral knee support. Acted on by: - Tensor fascia latae - Gluteus maximus

Question 131

Innervation of hamstrings

Answer 131

Scaiatic nerve

Question 132

List hamstrings muscles

Answer 132

o Semitendinosus o Semimembranosus o Biceps femoris

Question 133

What is pes anserinus made up of?

Answer 133

3 conjoined tendons of muscles. One from each thigh compartment.

Question 134

Name the muscle tendons that conjoin to form pes anserinus

Answer 134

 Sartorius – from anterior thigh compartment  Gracilis – from medial thigh compartment  Semitendinosus – from posterior thigh compartment

Question 135

Contents of popliteal fossa

Answer 135

 Popliteal artery  Popliteal vein  Tibial nerve  Common fibular nerve

Question 136

How to test for posterior cruciate ligament damage?

Answer 136

o Flex knee to 90 degrees o Look from the side of the knee checking for a poster sag or setback of the tibia o This would suggest posterior cruciate ligament damage

Question 137

Describe the anterior draw test (for anterior cruciate ligament)

Answer 137

o Place both hands around upper tibial tuberosity + index finger tucked under the hamstrings to make sure these are relaxed o Stabilise the lower tibia with your forearm + gently pull the upper tibia forward o In a relaxed, normal patient there is normally a small degree of movement o More significant movements suggest anterior cruciate ligament damage

Question 138

How to test medial + lateral collateral ligament?

Answer 138

o Flex knee to 15 degrees o Alternatively stress the joint line on each side o Place hand on opposite side of the joint line of that which you are testing + apply force to lower tibia

Question 139

What is knock knees aka?

Answer 139

Genus valgus

Question 140

What is bol-legs aka?

Answer 140

Genu varus

Question 141

The chief cause of genu varus

Answer 141

Rickets

Question 142

When does ACL rupture occur?

Answer 142

o Occurs when the biomechanical limits of the ligament are exceeded (over-stretched) o Frequently occurs in athletes o Consequence depends on how much knee stability affected + the extent to which other structures have been involved o If instability is evident then the menisci may get injured, this may lead to progressive, degenerative, arthritis of the knee

Question 143

PCL rupture

Answer 143

o <20% of knee ligament injuries o Usually caused by blow to knee whilst flexed  E.g. falling on bent knee, impact from dashboard

Question 144

What is the terrible triad?

Answer 144

Torn:  Medial (tibial) collateral ligament  Medial meniscus  Anterior cruciate ligament

Question 145

How to know which collateral ligament is damaged?

Answer 145

 Pain on medial rotation indicates damage to the medial ligament.  Pain on lateral rotation indicates damage to the lateral ligament o If tibial (medial) collateral ligament is damaged, it is likely that medial meniscus is torn, due to their attachment

Question 146

From proximal to distal, name the 7 tarsals

Answer 146

Talus. Calcaneus. Navicular. Cuboid. Cuneiforms (there are 3 of these)

Question 147

Which tarsal bone articulates with ankle joint?

Answer 147

Talus

Question 148

Name the largest tarsal

Answer 148

Calcaneus. Achilles tendon attaches to it.

Question 149

Which compartment does the dorsiflexors lie in?

Answer 149

Anterior leg

Question 150

Which compartment do ankle evertors belong to?

Answer 150

Lateral leg

Question 151

Which compartment do plantar flexors belong to?

Answer 151

Posterior leg

Question 152

Which compartment does the deep fibular nerve supply?

Answer 152

Anterior leg compartment

Question 153

Which compartment does the superficial fibular nerve supply?

Answer 153

Lateral leg compartment

Question 154

Which compartment does the tibial nerve supply?

Answer 154

Posterior leg

Question 155

Which compartment does the anterior tibial artery supply?It continues as dorsalis pedis

Answer 155

Anterior leg

Question 156

Which compartment does the posterior tibial artery supply? It is a continuation of the popliteal arterty

Answer 156

Posterior leg compartment

Question 157

Which compartment does the fibular artery supply?

Answer 157

Lateral leg compartment

Question 158

Name the 3 dorsal foot muscles

Answer 158

 Extensor digitorum brevis  Extensor hallucis brevis  Dorsal interossei

Question 159

Name the 3 superficial plantar foot muscles

Answer 159

* Abductor hallucis * Flexor digitorum brevis * Abductor digiti minimi

Question 160

Name 2 intermediate plantar foot muscles

Answer 160

* Quadratus plantae | * Lumbricals

Question 161

Name 4 deep plantar foot msucles

Answer 161

* Flexor hallucis brevis * Adductor hallucis * Flexor digiti minimi brevis * Plantar interossei

Question 162

Short saphenous vein

Answer 162

 Found on the lateral side  Runs up the posterior leg + becomes the popliteal vein

Question 163

Great saphenous vein

Answer 163

 Anterior to medial malleolus = where the origin of the great saphenous vein is found.  This is the longest vein in the body.  Runs up until the inguinal ligament where it becomes the femoral vein.

Question 164

The tarsal tunnel runs from the medial malleolus to the calcaneal tuberosity. Tendon order only applies here, proximally the tibial artery + flexor digitorum longus swap. Using the mnemonic - ‘Tom, Dick, ANd Harry’ list tendons, arteryand nerve

Answer 164

T - Tibialis posterior tendon D - flexor Digitorum A - posterior tibial Artery N - tibial Nerve H - flexor Hallucis longus tendon

Question 165

What type of joint is the ankle joint (talocrural joint)?

Answer 165

Hinge joint - movements possible in 1 plane (plantarflexion + dorsiflexion)

Question 166

What is the subtalar joint?

Answer 166

An articulation between 2 of the tarsal bones in the foot (talus + calcaneus) Ball-and-socket

Question 167

Which movements occur at the subtalar joint?

Answer 167

It is the chief site within the foot for generation of eversion + inversion movements * Eversion movement is produced by muscles of the lateral leg compartment * Inversion movement – tibialis anterior muscles

Question 168

Which muscles produce plantar flexion and dorsiflexion at the talocrural joint?

Answer 168

* Plantarflexion – produced by muscles in posterior compartment of leg. * Dorsiflexion – produced by muscles in anterior compartment of leg.

Question 169

When is the ankle joint most stable?

Answer 169

Dorsiflexion - anterior talus held tightly in mortise. High heels force plantarflexion which increases injury risk as the joint is least stable in this position.

Question 170

How many arches does the foot have?

Answer 170

3

Question 171

Name the arches of the foot.

Answer 171

 2 longitudinal (medial + lateral) – formed between the tarsal bones + proximal end of metatarsals * Medial longitudinal arch - formed by the calcaneus, talus, navicular, 3 cuneiforms, first 3 metatarsal bones * Lateral longitudinal arch - formed by the calcaneus, cuboid, 4th + 5th metatarsal bones  1 anterior transverse • Formed by the metatarsal bases, the cuboid + the 3 cuneiform bones

Question 172

What does pes cavus mean?

Answer 172

High arches

Question 173

What does pes planus mean?

Answer 173

Low arches (flat footed)

Question 174

What is hallux vagus?

Answer 174

Hallux is deviated medially, towards the body Uncommon

Question 175

What is hallux valgus?

Answer 175

aka bunion. Hallux deviated laterally. 1st metatarsal bone deviates medially.

Question 176

What does the following describe?  Foot condition in which the longitudinal arches have been lost  Arches do not develop until about 2-3 years of age so flat feet during infancy is normal causes few, if any, symptoms – may result in ache after prolonged activity

Answer 176

Pes planus

Question 177

Posture A. Area demarcated by body’s point of contact with ground (+ any additional walking aids) B. Theoretical balancing point. C. A genetic term used to describe the dynamics of body posture to prevent falling. D. Point location of the body ground reaction foot vector (vGRF) on the floor. E. The orientation of any body-segment relative to the gravitational vector. F. Vertical projection of the COM onto the ground

Answer 177

E. The orientation of any body-segment relative to the gravitational vectorIt is an angular measure from the vertical

Question 178

Centre of mass A. Area demarcated by body’s point of contact with ground (+ any additional walking aids) B. Theoretical balancing point. C. A genetic term used to describe the dynamics of body posture to prevent falling. D. Point location of the body ground reaction foot vector (vGRF) on the floor. E. The orientation of any body-segment relative to the gravitational vector. F. Vertical projection of the COM onto the ground

Answer 178

B. Theoretical balancing point o Weighted average of the COM of each body segment combined in 3D space

Question 179

Balance A. Area demarcated by body’s point of contact with ground (+ any additional walking aids) B. Theoretical balancing point. C. A genetic term used to describe the dynamics of body posture to prevent falling. D. Point location of the body ground reaction foot vector (vGRF) on the floor. E. The orientation of any body-segment relative to the gravitational vector. F. Vertical projection of the COM onto the ground

Answer 179

C. A genetic term used to describe the dynamics of body posture to prevent falling o It is related to the inertial forces acting on the body + the inertial characteristics of body segments

Question 180

Centre of gravity A. Area demarcated by body’s point of contact with ground (+ any additional walking aids) B. Theoretical balancing point. C. A genetic term used to describe the dynamics of body posture to prevent falling. D. Point location of the body ground reaction foot vector (vGRF) on the floor. E. The orientation of any body-segment relative to the gravitational vector. F. Vertical projection of the COM onto the ground

Answer 180

F. Vertical projection of the COM onto the ground

Question 181

Centre of pressure A. Area demarcated by body’s point of contact with ground (+ any additional walking aids) B. Theoretical balancing point. C. A genetic term used to describe the dynamics of body posture to prevent falling. D. Point location of the body ground reaction foot vector (vGRF) on the floor. E. The orientation of any body-segment relative to the gravitational vector. F. Vertical projection of the COM onto the ground

Answer 181

D. Point location of the body ground reaction foot vector (vGRF) on the floor o When standing this is between the 2 feet

Question 182

Base of support. A. Area demarcated by body’s point of contact with ground (+ any additional walking aids) B. Theoretical balancing point. C. A genetic term used to describe the dynamics of body posture to prevent falling. D. Point location of the body ground reaction foot vector (vGRF) on the floor. E. The orientation of any body-segment relative to the gravitational vector. F. Vertical projection of the COM onto the ground

Answer 182

A. Area demarcated by body’s point of contact with ground (+ any additional walking aids) o When feet are separate apart, it is easier to maintain balance o A walking stick + frame will increase base of support --> more like to keep COG within that area --> maintain balance

Question 183

What does postural control consist of?

Answer 183

- Postural control consists of keeping body’s COG over/within base of support (BOS) during stance + active movements, respectively - 2/3rd of our body mass is located 2/3rd of body height above the ground

Question 184

Breakdown the sensory component of balance

Answer 184

Somatosensory – skin receptors:  Motion of the body with respect to support surface. Proprioceptive – muscle spindles + golgi tendon organs:  Motion of body segments relative to each otherSomatosensory + proprioceptive = 60-70% Visual – eyes (10-20%)  Motion of the body w/ resect to extra-personal space Vestibular – inner ear (10-20%):  Detects accelerations of the head

Question 185

What is the postural ankle strategy?

Answer 185

o In response to smaller, slower perturbations o Shifts COG about the ankle joint w/ minimal contribution from knee or hip o Distal to proximal muscle activation o Used on surfaces w/ low resistance to shear forces

Question 186

What is the postural hip strategy?

Answer 186

o In response to larger, faster perturbations o Shifts COG about hip joint by flexion/extension o Ability to generate larger torque, more rapid response o Produces mostly shear forces o Transmits horizontal shear force to surface, therefore not suitable for slippery surfaces o Suitable on surface that have low resistance to torque (narrow bean)

Question 187

What is the stepping strategy?

Answer 187

o In response to largest, fastest perturbation (or the inability to generate an ankle/hip strategy) o Shifts COG about hip joint by flexion/extension o Realigns BOS under the new position of the COG w/ rapid steps, hops or stumbles o Used when ankle + hip strategies are inadequate

Question 188

Describe balance in the elderly

Answer 188

o Progressive age-related changes in healthy elderly subjects o The old were more dependent on proprioceptive input o They were unable to visually compensate for the disruption if proprioceptive input o Disruption of proprioceptive input is the most important determinant of quantitative balance performance in >80 years o The old did not adapt as well to repeated platform perturbations compared with younger elderly o Deficit in central integration of sensory input or in motor output response

Question 189

Describe balance in fallers

Answer 189

o No significant difference in functional reach between non-fallers and fallers o No significant differences were found between non-fallers and fallers for the anterior LOS test o Significant difference found between non-fallers and fallers for the mean sensory organisation test o Significant positive correlation for anterior displacement on LOS test and SOT composite score for fallers but not for non-fallers

Question 190

Main function of fibrous layer of eyeball

Answer 190

To provide shape to eye + support deeper structures

Question 191

How many layers is the eyeball divided into?

Answer 191

3 main layers: - FIbrous - Vascular - Neural

Question 192

Name the innermost layer of the eyeball.

Answer 192

Neural layer

Question 193

Name the 2 main structures in the fibrous layer (they are continuous with each other).

Answer 193

Cornea (anteriorly) Sclera (posteriorly) - makes up 85% of fibrous layer

Question 194

Vascular layer consists of 3 main structures which are continuous with one another (anterior to posterior) name them.

Answer 194

Iris Ciliary body Choroid

Question 195

What is the coloured bit of the eye that changes pupil size called?

Answer 195

Iris

Question 196

Which structure makes up the majority of the fibrous layer?

Answer 196

Sclera

Question 197

Which structure in the eyeball provides attachment to the extraocular muscles responsible for movement of eye?

Answer 197

Sclera (white part of eye)

Question 198

Which structure provides 2/3rds of the focusing power of the eye?

Answer 198

Cornea (light entering eye is refracted by cornea)

Question 199

Which 2 muscles alter pupil size?

Answer 199

Dilatory muscles sympathetic stimulation) Anterior sphincter muscles

Question 200

When to dilator muscles relax?

Answer 200

In bright light, pupils smaller

Question 201

What action do miotics and mydriatics have on iris (hence pupil size)?

Answer 201

* Mydriatics dilate iris | * Miotics – constrict iris

Question 202

When do anterior sphincter muscles contract and relax?

Answer 202

* Contract in response to parasympathetic stimulation | * Relax in dim light so pupil larger

Question 203

Where is the iris situated between?

Answer 203

Lens and cornea

Question 204

What is the ciliary body?

Answer 204

Muscular layer that controls shape of lens and contributes to formation of aqueous humour

Question 205

How does the ciliary body focus on more distant and less distant objects?

Answer 205

 More focusing power (closer up objects) – lens get rounder  More distant objects – lens get flatter

Question 206

What is the ciliary body composed of?

Answer 206

CIliary muscles (smooth muscle fibres) and ciliary processes (attach to lens)

Question 207

What is the choroid?

Answer 207

o Connective tissue + dense vascular network that provides nutrients to outer surface retina o Choroid receives its blood supply from central retinal artery (that emerges from back of eye) o Retinal arteries + veins supply the inner surface of retina is (come in through optic nerve vasiculus) o Choroid provides all eye layers w/ 90% of their blood supply

Question 208

What is the light detecting part of the eye?

Answer 208

Retina

Question 209

The neural layer of the retina is split into 3 layers of nerve cells and 2 synapses. List them from deep to superficial.

Answer 209

* Photo receptor cells (outermost layer) – rods + cones * Bipolar cells – transmit signals from photoreceptors to ganglion cells * Ganglion cells (innermost layer) – final output neurons in the retina

Question 210

What are the rod and cone cells sensitive to?

Answer 210

o Rod cells – sensitive to dim light, provide black + white vision o Cone cells – sensitive to bright light, support perception of colour

Question 211

Name the other 2 types of cells in the middle layer along with bipolar cells.

Answer 211

Amacrine cells Horizontal cells

Question 212

Function of amacrine cells in neural layer.

Answer 212

Inhibitory neurons that interact with retinal ganglion cells and/por bipolar cells

Question 213

Function of horizontal cells found in middle layer of neural layer of eyeball

Answer 213

Integrate info horizontally allowing communication between adjacent cells

Question 214

The retina is composed of neural layer and pigmented layer. What is the function of pigmented layer?

Answer 214

 Acts to support neural layer + continues around whole inner eye surface  Anteriorly, the pigmented layer (non-visual retina) continues but the neural layer does not  Posteriorly + laterally, both layers of retina are present (optic part of retina)

Question 215

Where is the lens?

Answer 215

• Located between the vitreous humour + pupil

Question 216

What happens when the shape of the lens changes?

Answer 216

* The shape of the lens is altered by the ciliary body, changing its refractive power. * In old age, the lends can become opaque (cataract).

Question 217

Where is the anterior and posterior chambers located?

Answer 217

Anterior chamber - Located between cornea + iris. Posterior chamber - Located between iris + ciliary processes.

Question 218

What are both chambers of the eyeball filled with?

Answer 218

* Both chambers are filled w/ aqueous humour – clear plasma-like fluid that nourishes/protects eye * Aqueous humour is produced constantly + drains via the trabecular meshwork * Trabecular meshwork: an area of tissue at the base of the cornea, near the anterior chamber * If drainage of aqueous humour is obstructed, glaucoma can result

Question 219

The eyeball receives arterial blood primarily via which artery?

Answer 219

Ophthalmic artery

Question 220

What is the opthalmic artery a branch of?

Answer 220

Internal carotid

Question 221

The opthalmic artery gives rise to many branches which supply different components of the eye. Name the most important branch.

Answer 221

Central artery of the retina - supplies internal surface of retina. Occlusion of it will quickly result in blindness.

Question 222

Venous drainage of the eyeball is carried out by which veins?Where do they drain?

Answer 222

Superior and inferior ophthalmic veins They drain into cavernous sinus (a dorsal venous sinus in close proximity to the eye.

Question 223

Name 2 types of eye movements

Answer 223

o Gaze stabilisation (automatic) o Gaze shifting (voluntary)

Question 224

We have voluntary control over gaze shifting eye movements. Name the movements and describe them.

Answer 224

Saccade: • Directs eyes towards visual target (v. quickly) • We have most voluntary control over theseSmooth pursuit • Follows moving visual target e.g. tracking bird flying in sky Vergence: • Adjusts eyes for different viewing distance (depth)

Question 225

Name the 2 almost automatic gae stabilisation eye movements.

Answer 225

Vestibulo-Ocular Optokinetic

Question 226

LR6 SO4 R3 meaning?

Answer 226

Lateral rectus muscle innervated by CN 6 Superior oblique by CN 4 Remaining 4 muscles by CN3

Question 227

Main movement of superior rectus muscle?

Answer 227

Elevation

Question 228

Main movement of inferior rectus muscle

Answer 228

Depression

Question 229

Main movement of medial rectus

Answer 229

Adduction

Question 230

Main movement of lateral rectus

Answer 230

Abduction

Question 231

Main movement of superior oblique?

Answer 231

Intorsion

Question 232

Main movement of inferior oblique?

Answer 232

Extorsion

Question 233

Secondary movement of Inferior and superior oblique muscles have a tertiary movement of what?

Answer 233

Abduction

Question 234

Name the only muscle that is capable of elevating the eye when it is in a fully adducted position

Answer 234

Inferior oblique

Question 235

When is supplementary eye field used?

Answer 235

When planning eye movements

Question 236

When is the frontal eye field?

Answer 236

Part of primary motor cortex that controls eye movements

Question 237

When is posteiror parietal cortex used in eye movement control?

Answer 237

Visual attention

Question 238

When is superior colliculus used?

Answer 238

In orientation to an object in visual field that catches attention

Question 239

Miosis

Answer 239

o Pupil constriction o Iris sphincter active o Iris dilator relaxed o Response to light increase o Parasympathetic control o Relaxed state o Also helps focus (accommodation)

Question 240

Mydrasis

Answer 240

o Pupil dilationo Iris sphincter relaxed o Iris dilator active o Response to light decreases o Sympathetic control o Elevated emotional/aroused state o Let’s in more light

Question 241

Purpose of the accommodation reflex?

Answer 241

To focus on objects

Question 242

The accommodation reflex is under sympathetic or parasympathetic control?

Answer 242

Parasympathetic

Question 243

When does lens become rounder (thick)?

Answer 243

To focus on near object

Question 244

When does lens become thin?

Answer 244

To focus on distant object

Question 245

What is convergence?

Answer 245

* When looking at distant image, pupils diverge | * When looking at near image, pupils converge

Question 246

What type of humour is produced by ciliary body constantly and circulates through anterior chamber?

Answer 246

Aqueous

Question 247

Where does aqueous humour exit?

Answer 247

Thorough trabecular meshwork between iris + lens

Question 248

Function of aqueous humour

Answer 248

 Maintains intraocular pressure + inflates the globe of the eye  Provides nutrition for avascular ocular tissues  Presence of immunoglobulins indicated a role in immune response  Provides inflation for expansion of cornea  For refractive index

Question 249

In which chamber is aqueous humour produced?

Answer 249

Posterior chamber and then flows through narrow cleft between front of lens and back of iris to escape through the pupil into the anterior chamber

Question 250

Production to drainage route of aqueous humour

Answer 250

* Through posterior chamber (secreted by ciliary body) * Narrow space between posterior iris + anterior lens * Through pupil to enter anterior chamber * Trabecular meshwork * Schlemm’s canal

Question 251

Where is vitreous humour found?

Answer 251

 In area between lens + retina (posterior cavity/vitreous chamber)  Vitreous humour is fluid-like near the centre, and gel-like near the edges  It makes up 4/5th of the volume of the eyeball

Question 252

Function of vitreous humour

Answer 252

 It’s composed mostly of phagocytes, which remove unwanted cellular debris in the visual field  Unlike the fluid aqueous humour which is continuously replenished, the gel in the vitreous chamber is stagnant  Therefore, if blood, cells, or inflammation by-products get into vitreous, they remain there unless surgically removed• These are known as floaters

Question 253

What is opacification (clouding) of the lens caused by compaction + protein deposition, commonly known as?

Answer 253

Cataracts

Question 254

Most common type og glaucoma?

Answer 254

Primary open-angle glaucome

Question 255

Glaucoma treatment

Answer 255

Beta- blockers, alpha-2-adrenoceptor agonist, carbonic anhydrase, prostaglandin analogues, miotics (muscarinic agonist

Question 256

What is papilloedema?

Answer 256

o Swelling of optic disc, visible during ophthalmoscopy o The optic disc is the area of the retina where the optic nerve enters o Swelling occurs secondary to raised intracranial pressure o High pressure within cranium resists venous return from the eye o This causes fluid to collect in the retina -> swollen optic disc

Question 257

Describe horner's syndrome.

Answer 257

Triad of symptoms produced by damage to the sympathetic trunk in the neck:  Partial ptosis (drooping of upper eyelid)  Miosis (pupillary constriction)  Facial anhydrosis (absence of sweating)

Question 258

Extraocular muscles are innervated by 3 cranial nerves. Damage to CN III causes what?

Answer 258

CN III – eye adopts a position known as ‘down + out’

Question 259

Damage to CN IV causes?

Answer 259

No obvious effect of the resting orientation of eyeball

Question 260

Damage to CN VI cause?

Answer 260

Affected eye is adducted by resting tone of medial rectus

Question 261

Protanopes lack which type of cone?

Answer 261

Lack 'L' red conesLong wavelengh

Question 262

Tritanopes lack which type of cone?

Answer 262

S (blue) conesNot x-linked (chromosome 7)Short wavelength

Question 263

Deuteranopes lack which type of cone?

Answer 263

M (middle wavelength) green cone

Question 264

What are anomalous trichromats?

Answer 264

People with 3 cone types, but one is 'weak', this is more common than dischromacy:

Question 265

What is protanomalous trichromat?

Answer 265

Weak red cones They shift their sensitivity to higher wavelength (more sensitive to green) making it difficult to distinguish between red + green

Question 266

What is deuteranomalous trichromat?

Answer 266

Weak green cones They shift their sensitivity to lower wavelength (more sensitive to red) making it difficult to distinguish between red + green

Question 267

What is. tritanomalous trichromat?

Answer 267

Weak blue cones

Question 268

Where do about 90% of the axons in the optic nerve fo to?

Answer 268

The lateral geniculate nucleus in the thalamus

Question 269

What happens at the optic chiasm?

Answer 269

o The optic nerves from both eyes meet and cross at the optic chiasm, at the base of the hypothalamus of the brain o Info coming from both eyes is combined and then splits according to the visual field o The corresponding halves of the field of view (R + L) are sent to the L + R halves of the brain, respectively, to be processed  R side of the primary visual cortex deals with the L half of the field of view from both eyes, + similarly for left brain

Question 270

What are optic tracts?

Answer 270

o Info right visual field (now on the left side of the brain) travels in the left optic tract o Info from the left visual field travels in the right optic tract o Each optic tract terminates in the lateral geniculate nucleus in the thalamus

Question 271

From eye to brain. Order the following: optic chiasm, optic nerve, optic tract, visual cortex, optic radiation, extrastriate visual areas, lateral geniculate nucleus

Answer 271

Optic nerve Optic chiasm Optic tract Lateral geniculate nucleus Optic radiation Visual cortex Extrastriate visual areas

Question 272

Name the sensory relay nuclei in the thalamus of brain for visual info.

Answer 272

Lateral geniculate nucleus

Question 273

Name the primary visual cortex

Answer 273

Straite cortex

Question 274

Where does the primary visual cortex receive info from?

Answer 274

Directly from LGN

Question 275

Feature of the frontal lobe

Answer 275

Intellectual function Praxia - giving/carrying out tasks in ordered sequenceInhibition Bladder continence Saccadic eye movement - voluntary horizontal eye movements (eyes deviate towards side of destruction and away from side of irritation) Motor function Expression of language in dominant lobe (usually L)

Question 276

Features of tempral lobe

Answer 276

* Memory * Smell * Hearing * Vestibular function * Emotion (limbic system)

Question 277

Features of parietal lobe

Answer 277

Sensory integration o Info on sight/smell etc. comes from the other lobes o The parietal lobe interprets this info + integrates it together Receptive language o Making sense of language

Question 278

Occipital lobe

Answer 278

Vision - lesions may cause hemianopia

Question 279

Arterial supply to cerebrum

Answer 279

Anterior Cerebral Arteries - Branches of internal carotid arteries, supplying the anteromedial aspect of the cerebrum. Middle Cerebral Arteries - Continuation of internal carotid arteries, supplying most of the lateral portions of cerebrum. Posterior Cerebral Arteries - Branches of basilar arteries, supplying the medial + lateral sides of cerebrum posteriorly.

Question 280

Cranial nerve summary

Answer 280

• Cerebrum – cranial nerve I, II • Midbrain – cranial nerve III, IV o CN III emerges from pontine-medulla junction o CN IV comes from posterior side of midbrain + has longest intracranial length of all cranial nerves * Pons – cranial nerve V, VI, VII, VIII * Medulla – cranial nerve IX, X, XI, XII

Question 281

List features of cerebellar dysfunction (VANISH’D).

Answer 281

* Vertigo * Ataxia * Nystagmus * Intention tremor * Slurred, staccato, scanning speech * Hypotonia * Dysmtria

Question 282

Summary of brainstem

Answer 282

 Made up of: midbrain, pons, medulla  As a role, motor cranial nerve nuclei are situated more medially + purely sensory nuclei more laterally  Nerves with an intermediate function are in-between  Substantia nigra – dopamine production  Red nucleus – important for coordination  Respiratory centre  Cardiac centre  Reticular activating system  Conduit for white matter tracts * Eye movements * Motor – e.g. corticopontine, corticobulbar, corticospinal * Sensory – e.g. spinothalamic * Coordination – e.g. spinocerebellar

Question 283

Cerebellum summary (functional/anatomical sections)

Answer 283

* Vermis (vestibulocerebellum) – balance + equilibrium. * Paravermis (spinocerebellum) – postural tone. * Cerebellar hemispheres (pontocerebellum/cerebrocerebellum) – fine coordination

Question 284

What is this a definition of an abrupt loss of focal brain function lasting more than 24 hours due to either spontaneous haemorrhage into brain substance or inadequate blood supply to part of the brain i.e. ischaemia (thrombosis, embolism)?

Answer 284

Stroke

Question 285

What is Wernicke-Korsakoff syndrome?

Answer 285

o Associated w/ heavy drinking + malnutrition (B1 deficiency) o Combination of Wernicke’s encephalopathy + Korsakoff’s syndrome o Atrophy in mammillary bodies, thalamus, periaqueductal grey, wall of 3rd ventricle, cerebellum + frontal lobe  Amnesia – due to atrophy of the structures in the diencephalon  Confabulation – hold memories they think is true; anterograde + variable retrograde amnesia

Question 286

S+S of frontal lobe dementia?

Answer 286

o Disinhibited behaviour o Change in appetite – they develop a sweet tooth o Reduced sense of smell o Bladder dysfunction o Gait apraxia o Progressive motor (expressive) dysphasia

Question 287

S+S of temporal lobe epilepsy?

Answer 287

Memory :  Déjà vu – Somewhere familiar seems unfamiliar  Amnestic seizures – Don’t remember activities during seizure Smell:  Olfactory hallucinations Hearing:  Auditory hallucinations (noises/random words)Vestibular function  VertigoEmotion (limbic system)  Sudden anger/fear

Question 288

A lesion on R cranial nerve nuclei in the brainstem will cause what?

Answer 288

R sided (ipsilateral) LMN weakness

Question 289

A lesion to the R side of the spinal cord will cause what?

Answer 289

R sided (ipsilateral) UMN weakness below the level of the lesion

Question 290

A lesion in R motor cortex or in the R internal capsule will cause weakness where?

Answer 290

L sided (contralateral) UMN weakness

Question 291

Functionally, the ascending tracts can be divided by the type of info they transmit: - Conscious tracts - Unconscious tracts What are conscious tracts comprised of?

Answer 291

Dorsal column-medial lemniscal pathway (DCML) -  Fine touch, vibrations, proprioception Anterior spinothalamic tract – carries the sensory modalities of crude touch and pressure. Lateral spinothalamic tract – carries the sensory modalities of pain and temperature)

Question 292

Functionally, the ascending tracts can be divided by the type of info they transmit: - Conscious tracts - Unconscious tracts What are unconscious tracts comprised of?

Answer 292

Spinocerebellar tracts - unconcious proprioception: Posterior spinocerebellar tract – Carries proprioceptive information from the lower limbs to the ipsilateral cerebellum. Cuneocerebellar tract – Carries proprioceptive information from the upper limbs to the ipsilateral cerebellum. Anterior spinocerebellar tract – Carries proprioceptive information from the lower limbs. The fibres decussate twice – and so terminate in the ipsilateral cerebellum. Rostral spinocerebellar tract – Carries proprioceptive information from the upper limbs to the ipsilateral cerebellum.

Question 293

Which modalities does the anterior spinothalamic tract carry?

Answer 293

Crude touch and pressure

Question 294

Which modalities does the lateral spinothalamic tract carry?

Answer 294

Pain and temp

Question 295

Which modalities does the DCML carry?

Answer 295

Fine touch, vibration, proropception

Question 296

Which modalities does the spinocerebellar tracts carry?

Answer 296

Unconscious poproioception

Question 297

Where do DCML tracts decussate?

Answer 297

Contralateral – decussate in medulla

Question 298

Where do spinothalamic tracts decussate?

Answer 298

Contralateral – decussate in spinal cord (2-3 levels above entry)

Question 299

Where do spinocerebellar tracts decussate?

Answer 299

They don't. | They are ipsilateral

Question 300

Motor (descending) tracts can be divided into pyramidal and extrapyramidal groups.Name the pyramidal tracts.

Answer 300

Corticospinal | Corticobulbar

Question 301

Motor (descending) tracts can be divided into pyramidal and extrapyramidal groups.Name the extrapyramidal tracts.

Answer 301

Vestibulospinal Tectospinal Reticulospinal Rubrospinal

Question 302

Where do pyramidal tracts originate and what are they responsible for?

Answer 302

 Originate in cerebral cortex and go to spinal cord + brainstem  Responsible for voluntary control of musculature of body + face

Question 303

Where do extrapyramidal tracts originate and what are they responsible for?

Answer 303

 Originate in the brain stem and go to spinal cord  Responsible for muscle tone, balance, posture + locomotion

Question 304

What do lateral corticospinal tracts control?

Answer 304

Distal muscles

Question 305

What do anterior corticospinal tracts control?

Answer 305

Proximal movements

Question 306

Are corticospinal (pyramidal) tracts contralateral or ipsilateral? Where do they decussate if they do?

Answer 306

Contralateral - 90% decussate in medulla (lateral corticospinal) Ipsilateral - 10% decussate in spinal cord (anterior corticospinal

Question 307

What do corticobulbar tracts supply?

Answer 307

Muscles of face and neck

Question 308

What muscles do vestibulospinal tracts innervate?

Answer 308

Balance and posture

Question 309

Are vestibulospinal, tectospinal, reticulospinal, rubrospinal, corticobulbar, corticospinal tracts contralateral or ipsilateral?

Answer 309

Vestibulospinal - ipsilateral Tectospinal - contralateral Reticulospinal - ipsilateral Rubrospinal - contralateral Corticobulbar - mixed Corticospinal - contralateral

Question 310

Desrribe a CN XII palsy

Answer 310

 Tongue deviates towards the side of the weakness, not the side of the lesion  Ipsilateral in LMN lesion  Contralateral in UMN lesion

Question 311

CN XII lesion

Answer 311

 Wastage of muscle + probably fasciculations  Weakness of tongue  Dysarthria

Question 312

What does the hypoglossal nerve CN XII supply?

Answer 312

Motor function of tongue

Question 313

What does CN XI control?

Answer 313

 Turning of head – sternocleidomastoid muscle |  Shrugging of shoulders – trapezius muscle

Question 314

CN XI palsy can be caused during neck injury. What does it look like?

Answer 314

Sternocleidomastoid and trapezius muscles do not contract when patient shrugs or turns head on one side

Question 315

What's Bell's palsy?

Answer 315

LMN lesion of facial nerve (CN VII)

Question 316

Facial nerve lesion of UMN and LMN

Answer 316

 UMN lesion – Gives rise to contralateral weakness of bottom half of the face  LMN lesion – Gives rise to weakness of the whole side of the ipsilateral face (Bell’s palsy)Muscles of the forehead are represented bilaterally in the cortex and so an UMN lesion of one side can be overcome by the opposing side

Question 317

How is muscle bulk, tone, power affected by UMNLs and LMNLs?

Answer 317

UMNL - Bulk decreases - Tone increases - Power increases LMNL: - Bulk decreases more than UMNL - Tone decreases - Power decreases

Question 318

How are reflexes affected in an UMN and LMN lesions?

Answer 318

UMNL - increases | LMNL - decreases

Question 319

CN III lesion (oculomotor nerve)

Answer 319

o Eye is situated ‘down + out’ o Pupil dilated – oculomotor n. supplies parasympathetic fibres responsible for pupillary constriction o Partial ptosis – from paresis of levator palpebrae superioris

Question 320

Describe decerebrate posturing (damage to upper brainstem)

Answer 320

o Arms adducted o Legs extended o Feet plantar flexed o Wrists pronated o Fingers flexed

Question 321

Describe decorticate posturing (damage to corticospinal tracts)

Answer 321

o Arms adducted + flexed o Wrists + fingers flexed on chest . o Legs extended + internally rotated o Feet plantar flexed

Question 322

Arefasciculations present in an UMN or LMN lesion?

Answer 322

LMN

Question 323

Gait summary

Answer 323

 Spastic – scissoring if bilateral  Cerebellar – broad based + unsteady (they walk like drunk)  Frontal (marche a petit pas) – small steps (looks similar to parkinsonian)  Parkinsonian – slow + shuffled becoming festinant in later stages  Waddling – proximal leg muscle weakness  Antalgic – if sensory dysaesthesia in feet  High steppage (equine – lift feet high like horse) – if sensory loss in feet  Dropped foot gait – if weakness of ankle dorsiflexion  Atasia-abasia – psychological; malingering

Question 324

What is anterior spinal artery syndrome

Answer 324

o Anterior spinal artery (primary blood supply to the anterior portion of the spinal cord) is interrupted o Causing ischaemia or infarction of spinal cord in anterior 2/3 of the spinal cord + medulla oblongata

Question 325

What is. anterior spinal artery syndrome characterised by?

Answer 325

 Loss of motor function below the level of injury  Loss of temperature and pain sensation (spinothalamic)  Preservation of sensations carried by the posterior columns – Fine touch, vibration, proprioception

Question 326

Central cord lesion is characterised by?

Answer 326

o Characterised by loss of motion + sensation in arms + hands o Usually results from trauma --> causes damage to neck --> major injury to central grey matter of spinal cord o Sensation above + below level of damage is normal, but as level of damage there’s compromised sensation  Hung sensory loss  Disassociative sensory loss  UMN signs below level if pressure on corticospinal tracts

Question 327

4 types of stroke

Answer 327

Haemorrhagic Thromboembolic Embolic Lacunar

Question 328

What is haemorrhagic stroke?

Answer 328

Blood vessels in brain rupture --> spilling blood into surrounding tissues

Question 329

What is thromboembolic stroke?

Answer 329

Blood clot develops in blood vessels inside brain

Question 330

What is embolic stroke. List causes of it

Answer 330

Blood clot develops elsewhere in body + breaks loose --> carried in blood to plug vessel in brain ``` Causes: o MI w/ dyskinesia cardiac chamber o Atrial fibrillation o Valvular heart disease o Endocarditis ```

Question 331

What is lacunar stroke?

Answer 331

Occlusion of small penetrating arteries that provide blood to brain’s deep structures

Question 332

Sites of brain haemorrhage?

Answer 332

o Intracerebral (stroke) o Subarachnoid o Subdural o Extradural

Question 333

o Occurs when blood accumulates between skull + dura mater o Typically follows head injury o High pressure bleeding is a prominent symptom A. Intracerebral (stroke) B. Subarachnoid C. Subdural D. Extradural

Answer 333

D. Extradural

Question 334

o Occurs when there is bleeding between the dura + arachnoid mater o Typically, is result of head moving rapidly forwards + stopping (such as in car accident) o This type of haemorrhage is more common than other ICHs in older people + alcoholics A. Intracerebral (stroke) B. Subarachnoid C. Subdural D. Extradural

Answer 334

C. Subdural

Question 335

o Bleeding between arachnoid + pia mater o A sudden, sharp headache usually precedes a subarachnoid haemorrhage o This type of ICH can be due to alcohol or drug abuse + tends to run in families A. Intracerebral (stroke) B. Subarachnoid C. Subdural D. Extradural

Answer 335

B. Subarachnoid

Question 336

o Bleeding in brain caused by the rupture of blood vessels within the head o This is not usually result of injury . o A prominent warning sign = sudden onset of neurological deficit. ``` Causes:  Rupture of aneurysm  Arteriovenous malformation  Carmona  Bleed into infract  Bleed into tumour  Trauma ``` A. Intracerebral (stroke) B. Subarachnoid C. Subdural D. Extradural

Answer 336

A. Intracerebral (stroke)

Question 337

Different elements of postural control

Answer 337

Brainstem:  Most important  Controls automatic functions Cerebral cortex:  Controls voluntary control of posture

Question 338

How are LMNs organised in spinal cord?

Answer 338

 Posture – Motor neurons innervating axial or proximal musculature – located medially (ventromedial)  Voluntary – Motor neurons innervating distal musculature – located laterally (dorsolateral)

Question 339

Name the 4 descending tracts originating in the brainstem and terminating in the spinal cord, involved in controlling posture.

Answer 339

 Vestibulospinal tract – info from vestibular nuclei about sense of balance relative to gravity  Tectospinal tract – info from visual system (superior colliculus) used for orientating to visual stimuli  Pontine reticulospinal tract – brings info from pons for large movement of trunk + limbs  Medullary reticulospinal tract – brings info from medulla

Question 340

Function of vestibulospinal and tectospinal tracts?

Answer 340

 Function – keep head balanced on shoulders as body moves (controls posture of head + neck)

Question 341

Name the tract that carrying sensory input from vestibular labyrinth in inner ear

Answer 341

Vestibulospinal tract

Question 342

Which tract carries input from retina to superior colliculus (optic tectum)?

Answer 342

Tectospinal tract

Question 343

What is decerebrate rigidity?

Answer 343

Massive increase in tone of extensor muscles caused by disinhibition of brainstem nuclei. Normally the tonic activity of the lateral vestibular + reticular nuclei in brainstem (causing muscle extension) are under tonic inhibitory control by cerebral + cerebellar inputs.

Question 344

What is the decerebrate response?

Answer 344

With extensive cortical damage, there is increase extensor tone due to brainstem action wo/ cerebral inhibition

Question 345

Where is the vestibular system located?

Answer 345

Located in the inner ear, just above cochlea

Question 346

All info from vestibular system is carried by which nerve?

Answer 346

Vestibular nerve (vestibular branch of vestibulocochlear nerve, CN VIII)

Question 347

Function of vestibular system

Answer 347

o Provides sense of balance o Motion detectors o Provides info about head orientation, displacement, and movement in 3D space

Question 348

Otolith organs + semicircular canals contain hair cells which do what?

Answer 348

Convert motions in the head to neural signals

Question 349

Name the 2 otolith organs

Answer 349

Utricle + saccule. They sense motion in 2 different directions

Question 350

Does the utricle or saccule sense motion in vertical direction?

Answer 350

Saccule

Question 351

Does the utricle or saccule sense motion in horizontal direction?

Answer 351

Utricle

Question 352

Both the utricle and saccule (otolith organs) work inthe same way. They are made up of hair cells and gelatinous cap. How does the. utricle maculae encode horizontal linear motion and acceleration?

Answer 352

 Moving head side to side which changes utricle  Macula is horizontal  Kinocilia towards striola (midline along centre of macula)  Mainly encodes horizontal linear motion + acceleration

Question 353

Moving head up and down causes in changes saccule. What does this encode?

Answer 353

Verticle linear motion and acceleration

Question 354

Difference between kinocilia and sterocilia (hair cells that generate APs at a steady baseline rate, hey can be inhibited or excited)

Answer 354

* Kinocilia – longer ones * Sterocilia – the rest The cilia may be: * Excited (depolarised) – when cilia are pushed in direction of kinocilium * Inhibited (hyperpolarised) when cilia are pushed in direction of stereocilium

Question 355

What is otoliths?

Answer 355

Calcium carbonate crystals that encrust the surface of the gelatinous cap They act like weights - tilting head down causes gravity pulls crystals down which causes drags gelatinous cap down which causes gelatinous cap displaces hair cells

Question 356

Function of sermicricular canals?

Answer 356

Sensitive to head rotation; rotational motion + angular acceleration

Question 357

How is 3D space represented by the anterior, posterior, horizontal (lateral) semicircular canals?

Answer 357

* The canals on both sides of head (in each ear) work together. * They are filled w/ a fluid called endolymph. * Main sensory structure of each canal located in the ampulla (base on canals).

Question 358

Seicircular canals summary

Answer 358

* Semicircular canals have an otolith like structure called ‘cupula’ in the ampulla. * The cupula is a gelatinous structure. * Inside there are hair cells embedded. * Moving the head one way will cause endolymph to move in the same direction. • This displaces the cupula + pushes it in opposite direction . • This triggers hair cells to depolarise (opposite side will hyperpolarize).

Question 359

The sensory nerve fibres (CN VIII) project info from semi-circular canal and otolith organs to vestibular nuclei in brainstem. They send projections via medial longitudinal fasciculus to?

Answer 359

 Cerebellum – important for coordination of movement in response to head/body position changes  Limb motor neurons – to control axial muscles + proximal limb muscles  Extra-ocular motor neurones (CN III, IV, VI) – to control extraocular eye muscles .  Neck motor neurones – to control head position

Question 360

Vestibulo-ocular reflex?

Answer 360

The compensatory movement of the eyes in the opposite direction of head rotation o Input from vestibular system (semicircular canals or otolith organs) directly to the extra-ocular muscles o Causes compensatory movement of eyes in the opposite direction of head movement so one can keep the visual world stable on retina during movement

Question 361

Function of vestibulo-ocular reflex?

Answer 361

Maintain stable vision during head movements o Person turns head to the left. o Left horizontal canal excited (right inhibited). o Signal sent to vestibular nuclei, then to oculomotor nuclei. o Right abducens (CN VI) flexes right lateral rectus. o Left oculomotor nerve (CN III) flexes left medial rectus. o Eyes turn to the right.

Question 362

VOR and posture

Answer 362

o Allows image to remain steady on retina despite head movements. o If it is not working, then corrective eye movements are not made. o Disconcerting feeling that world is moving when head moves, makes standing, walking, maintaining posture very difficult. o Because it is vestibular system-based, it still works in the dark or when you have your eyes closed.

Question 363

Caloric testing?

Answer 363

 Irrigate ear with cold or warm water.  Temp gradient will set up convection currents in endolymph, distorting the cupula to increase firing of afferents.  Induces the VOR. Results:  Brainstem intact – both eyes move towards the side with the water in ear.  Medial longitudinal fasciculus lesion – only eye. closest to water moves towards water, the other stays still.  Low brainstem lesion – no VOR at all, eyes stay still.

Question 364

What is Meniere's syndrome?

Answer 364

o Endolymphatic hydrops o Idiopathic increase in volume of endolymph distrust function of membranous labyrinth of inner ear

Question 365

Symptoms of Meniere's syndrome

Answer 365

Symptoms: attacks of vertigo, deafness, tinnitus (because endolymph also in cochlea)

Question 366

Meniere's syndrome treatment

Answer 366

Treatment: no cure, but can treat vertigo, nausea + vomiting with: prochlorperazine + antihistamines

Question 367

Cause of Benign paroxysmal positional vertigo?

Answer 367

Caused by calcium carbonate crystals dislodged from otolith organs, disrupting flow of endolymph in semicircular canals

Question 368

BPPV symptoms

Answer 368

Suddenly feeling dizzy on moving head in a certain direction; rolling over in bed (room spinning); nausea/vomiting

Question 369

BPPV treatment

Answer 369

Epley or Semont manoeuvre reposition CaCO3 crystals

Question 370

To maintain posture we need what type of tone?

Answer 370

Significant extensor tone

Question 371

Sound in the cochlea

Answer 371

o Sound wave travels through external ear, causes vibration of ear drum + ossicles o Footplate of stapes vibrates in oval window o Causes wave to travel along scala vestibuli in perilymph and back along scala tympani to round window (loose membrane where sound is absorbed) o Also causes displacement of basilar membrane and vibration of organ of Corti

Question 372

Basilar membrane

Answer 372

o Most stiff nearest to base of cochlea and least stiff at helicotrema  Thus, only high-frequency sound can displace basilar membrane at the base  Lower frequencies will travel further along the cochlea (before crossing membrane) o High-pitched sounds sensed at the base of cochlea, low pitches at apex – this is known as tonotopy

Question 373

Organ of Corti

Answer 373

o Located in cochlear duct o Transduces pressure waves into action potentials o Contains 15,000-20,000 auditory receptors, each with its own hair cell o Displacement of basilar membrane --> shear of hair cells --> opening non-selective transduction ion channels --> depolarisation

Question 374

Cochlear hair cells

Answer 374

o Outer hair cells – Amplify mechanical input to inner hair cells o Inner hair cells – Send information to brain via spiral Cochlear hair cells are identical to sensory hair cells found in vestibular part of labyrinth

Question 375

Function of auricle (aka pinna)

Answer 375

* Capture + transmit sound to external acoustic meatus * Funnels sound into ear canal * Aids in the vertical localisation of sounds * Filters sound (human auricle preferentially selects sounds in frequency range of human speech) * In other mammals, pinna may have other roles – signalling mood; assisting thermoregulation

Question 376

Innervation and vasculature of auricle

Answer 376

Innervation: • Greater auricular n. • Lesser occipital n. • Branches of the facial + vagus nerves Vasculature (arteries + veins): • Posterior auricular • Superficial temporal • Occipital

Question 377

Structure of external acoustic meatus

Answer 377

* Sigmoid shaped tube; 7mm in diameter + ~25mm long * Extends from concha of auricle to tympanic membrane * Has double layered structure covered w/ skin on outside + mucus membrane on inside * Contains hair, sebaceous + ceruminous (ear wax) glands * Walls are given their structure by: cartilage from auricle + bony support from temporal bone * It is connected to surrounding temporal bony by a fibrocartilaginous ring

Question 378

Function of external acoustic meatus

Answer 378

* Focuses sound energy on ear drum | * Amplifies by 10-15dB, sound corresponding to frequencies of human speech

Question 379

Function of middle ear

Answer 379

o Transmit vibrations from tympanic membrane to inner ear via the 3 bones (ossicles) o Ossicles amplify the sound waves by 20x

Question 380

Structure of middle ear

Answer 380

o It is the air-filled chamber between ear drum + inner ear o Middle ear lies within the temporal bone o Middle ear can be split into 2 sections:tympanic cavity and epithympanic recess

Question 381

List bones of the middle ear from outer to inner

Answer 381

Malleus (hammer). Incus (anvil). Stapes (stirrup).

Question 382

Name the 2. muscles of the middle ear

Answer 382

Tensor tympaniStapedius

Question 383

Tensor tympani

Answer 383

o Attached to the handle of malleus o Innervated by the mandibular part of trigeminal nerve (CN V) o Activated during chewing

Question 384

Stapepdius

Answer 384

o Attached to the stapes o Innervated by facial nerve (CN VII) o Activated during speaking

Question 385

Auditory tube (eustachian tube)

Answer 385

 This tube is normally closed – opens when there are pressure changes between outer + middle ear.  It is a cartilaginous + bony tube that connects the middle ear to the nasopharynx.  Acts to equalise pressure of middle ear to that of the extender auditory meatus.  In joining 2 structures, it’s a pathway by which an upper respiratory infection can spread into middle ear.  This tube is normally closed – opens when there are pressure changes between outer + middle ear.  It is a cartilaginous + bony tube that connects the middle ear to the nasopharynx.  Acts to equalise pressure of middle ear to that of the extender auditory meatus.  In joining 2 structures, it’s a pathway by which an upper respiratory infection can spread into middle ear.

Question 386

Main functions of inner ear?

Answer 386

Cochlea uses movement of fluid to sense external pressure changes (sounds) - Conversion of mechanical (kinetic) signals from middle ear (ossicles)  hydraulic energy of fluid in inner ear  electrical signals in vestibulocochlear nerve (CN VIII) - Which can transfer info to auditory pathway in the brain Vestibular part of labyrinth uses movement of fluid to sense rotational + translational accelerations to maintain balance

Question 387

Where is the. inner ear located?

Answer 387

WIthin the petrous part of the. temporal bone

Question 388

Name the 2 components of. the inner ear

Answer 388

Bony labyrinth and Membranous labyrinth

Question 389

What is the bony labyrinth composed of?

Answer 389

Cochlea, vestibule, 3 semicircular canals

Question 390

Semi-circular canals

Answer 390

 There are 3: anterior, lateral, posterior canals  Contain semi-circular ducts, which are responsible for balance (along w/ utricle + saccule)  The canals are situated superioposterior to vestibule  They have a swelling at one end, the ampulla

Question 391

Hearing

Answer 391

* Sound waves travel through external ear, cause vibration of ear drum = ossicles * Foot plate of stapes vibrates in oval window * Wave travels along scala vestibuli in perilymph + back along scala tympani to round window * Also causes displacement of basilar membrane + vibration of Organ of Corti

Question 392

Cochlea has 3 sections (chamber)

Answer 392

* Scala vestibuli – filled w/ perilymph * Scala media (or cochlear duct) – filled w/ endolymph * Scala tympani – filled w/ perilymph

Question 393

Vestibule

Answer 393

 Central part of body labyrinth  Separated from middle ear by oval window  Communicates anteriorly w/ cochlea + posteriorly w/ the semi-circular canal  2 parts of membranous labyrinth: saccule + utricle – are located within vestibule

Question 394

Cochlea

Answer 394

 Houses cochlea duct of membranous labyrinth – auditory part of inner ear  It twists upon itself around a central portion of bone called the modiolus  Branches from the cochlear portion of CN VIII are found at base of modiolus

Question 395

Membranous labyrinth

Answer 395

* System of tubes + chambers within bony labyrinth, filled w/ endolymph (fluid w/ high K+ conc) * Bony + membranous labyrinth separated by layer of perilymph (fluid w/ high Na+ conc) * Membranous labyrinth conforms to shape of bony part except in vestibule region * Consists of the cochlear duct, semi-circular ducts, utricle + saccule

Question 396

Cochlear duct

Answer 396

 Situated within cochlea + filled w/ endolymph  Organ of hearing – houses epithelial cells of hearing + organ of corti

Question 397

Saccule and utricle

Answer 397

 2 membranous sacs located in the vestibule  Endolymph drains from saccule + utricle into endolymphatic duct  Duct travels through vestibular aqueduct to post. aspect of petrous part of temporal bone  Here the duct expends to a sac where endolymph can be secreted + absorbed

Question 398

Semicircular ducts

Answer 398

 Located within semicircular canals (share their orientation)  Upon movement of head, flow of endolymph within ducts changes speed and/or direction  Sensory receptors in the ampullae of semi-circular canals detect this change + send signals to brain, allowing for processing of balance

Question 399

The inner ear has 2 openings into the idle ear, both covered by membranes. Oval and round window. Where does the oval window lie?

Answer 399

Oval window – lies between middle ear + vestibule

Question 400

Where does the round window lie?

Answer 400

Round window – separates middle ear from scala tympani (part of cochlear duct)

Question 401

The body labyrinth and membranous labyrinth have different arterial supplies. The bony labyrinth receives 3 arteries, which also supply the surrounding temporal bone. Name them

Answer 401

* Anterior tympanic branch (from maxillary artery) * Petrosal branch (from middle meningeal artery) * Stylomastoid branch (from posterior auricular artery)

Question 402

The membranous labyrinth is supplied by labyrinthine artery, a branch of inferior cerebellar artery (or, occasionally, the basilar artery). It divides into 3 branches - name them.

Answer 402

* Cochlear branch – supplies the cochlear duct | * Vestibular branches (x2) – supply the vestibular apparatus

Question 403

Sound wave is transmitted through 4 separate mediums. Name them.

Answer 403

Outer ear - air Middle ear - mechanical Inner ear - liquid Brain - neural

Question 404

From vestibulocochlear nerve (CN VIII), sound impulse travels through auditory pathway to the auditory cortex. Using the mnemonic SLIM list where the impulses travel.

Answer 404

 Superior olivary complex  Lateral lemniscus  Inferior colliculus  Medial geniculate nucleus

Question 405

Where does decussation occur in the auditory pathway?

Answer 405

Decussation occurs between the cochlear nuclei and superior olivary complex, and at inferior colliculi

Question 406

Where is the auditory cortex located?

Answer 406

Temporal lobe at margin with frontal lobe. Brodmann areas 41 and 42

Question 407

Auditory cortex

Answer 407

o Axons leaving the medial geniculate nucleus project to the auditory cortex via the internal capsule in an array. o The auditory cortex is tonotopic, like the basilar membrane.  I.e. high frequencies processed at the posterior part and low frequencies at the anterior part

Question 408

Sound localisation

Answer 408

Decussation enables inputs from left + right ears to be compared in superior olivary nuclei (SON) + localise sound  Medial SON – Detects differences in the time that sounds reach each ear • Localisation of low-frequency sound (<800Hz) occurs by detection of time differences in sound reaching each ear  Lateral SON – Detects differences in sound intensity reaching each ear • Localisation of high-frequency sound (>1600Hz) occurs by detection of differences in sound intensity at each ear. A mixture of both methods is used for sounds between 800 + 1600Hz

Question 409

Common causes of conductive hearing loss

Answer 409

 Infection – otitis externa + otitis media  Build-up of earwax  Perforated eardrum  Fluid in the middle ear  Membrane tension  Damage to the small bones within the middle ear

Question 410

Conductive hearing loss

Answer 410

Sounds become quieter, although not usually distortedDepending on its cause, a conductive hearing loss can either be temporary or permanent

Question 411

Common causes of sensorineural hearing loss

Answer 411

 Presbycusis – naturally occurs damage to cochlea when ageing  Noise-induced – regular + prolonged exposure to loud sounds  Ototoxic drugs  Inflammatory disease e.g. measles, mumps, meningitis, syphilis  Complications at birth  Congenital  Physical trauma  Benign tumours on the auditory nerve  Meniere’s disease

Question 412

Sensorineural hearing loss

Answer 412

o Problem in cochlea (organ of corti), vestibulocochlear nerve, auditory cortext of brain o This type of hearing loss is sometimes referred to as sensory, cochlear, neural, or inner ear hearing loss o A permanent sensorineural hearing loss is the result of damage to hair cells within the cochlea or hearing nerve (or both) o Sensorineural hearing loss changes our ability to hear quiet sounds, + reduces the quality of the sounds heard, meaning that individuals with this type of hearing loss will often struggle to understand speech o Once the cochlea hair cells become damaged, they will remain damaged for the rest of a person's life, therefore sensorineural hearing loss is irreversible + cannot be cured

Question 413

- Rinne and Weber tests are exams that test for hearing loss - They help determine whether the individual may have conductive or sensorineural hearing loss What is the Rinne test?

Answer 413

Rinne test evaluated hearing loss by comparing air conduction to bone conduction  Air conduction hearing occurs through air near the ear, and it involves the ear canal and eardrum  Bone conduction hearing occurs through vibrations picked up by the ear's specialised nervous system

Question 414

Results of Rinne test?

Answer 414

 Normal hearing will show an air conduction time that is twice as long as the bone conduction time – AC > BC  Conductive hearing loss – Bone conduction (BC) is heard longer – BC > AC  Sensorineural hearing loss – Air conduction (AC) is heard longer but may not be twice as long – AC > BC

Question 415

What test is this?  Strikes a tuning fork and places it on the middle of patient’s head  Note where the sound is best heard – the left ear, the right ear, or both equally

Answer 415

Weber test

Question 416

Results of Weber test

Answer 416

 Normal hearing will produce equal sounds in both ears  Conductive hearing loss – Sound to be heard best in abnormal ear  Sensorineural hearing loss – Sound to be heard best in normal ear

Question 417

Are most strokes ischaemic or haemorrhagic?

Answer 417

Ischaemic (85%)

Question 418

Types of ischaemic strokes.

Answer 418

 Thrombosis – Obstruction of a blood vessel by a blood clot forming locally  Embolism – Obstruction due to an embolus from elsewhere in the body  Systemic hypoperfusion – General decrease in blood supply (e.g. in shock)  Cerebral venous sinus thrombosis – Obstruction in the dural venous sinuses

Question 419

Types of haemorrhagic stroke

Answer 419

 Cerebral haemorrhage (intracerebral haemorrhage) – bleeding within the brain itself  Subarachnoid haemorrhage – Bleeding that occurs outside the brain tissue but still within the skull (between the arachnoid mater and pia mater)

Question 420

Causes of infarct in young people?

Answer 420

 Dissection – commonest cause in young people  Cardio-embolism – due to: patent foramen ovale (PFO), endocarditis  Vasculitis (uncommon)  Genetic – very rare, e.g. CADASIL, Fabrys, MELAS  Illicit drug use – amphetamines, cocaine

Question 421

Intracranial haemorrhage causes in young people?

Answer 421

 Arteriovenous malformation (AVM) – abnormal blood vessel connections, fragile vessels burst  Aneurysm – may be familial

Question 422

``` Are these medications taken by ischaemic or haemorrhagic stroke?  Clopidogrel  Statin  Anti-hypertensive  Anticoagulant if AF ```

Answer 422

Ischaemic stroke

Question 423

What do people end up taking after haemorrhagic stroke?

Answer 423

Anti-hypertensives

Question 424

Non modifiable risk factors for stroke?

Answer 424

o Age o Gender o Race – south Asian’s w/ western lifestyle o Family history – rarely congenital

Question 425

Modifiable risk factors for stroke?

Answer 425

Hypertension - most important for cerebral haemorrhage Diabetes Atrial fibrillation Smoking Hyperlipidaemia Obesity

Question 426

Parietal lobe

Answer 426

o Post central gyrus – Sensory cortex o Wernicke's area – Receptive area for language comprehension  Damage causes receptive dysphasia (can hear words but cannot understand them) o Dominant – Handling numbers, calculations o Non-dominant – Concepts of body image + awareness of external environment o Visual pathways – Optic path runs through here

Question 427

Temporal lobe

Answer 427

o Auditory cortex o Learning + memory o Olfactory sensation o Emotional behaviour o Visual pathways

Question 428

Frontal lobe (including primary motor cortex)

Answer 428

o Contralateral movements – Arms, leg, face, trunk o Broca's area (dominant hemisphere) – Expressive centre for speech, damage causes expressive dysphasia o Prefrontal areas – Personality, initiative o Cortical inhibition of bladder + bowels – People with frontal lobe lesion may urinate/defecate in strange places

Question 429

Branches of external carotid

Answer 429

``` o Some – Superior thyroid o Ancient – Ascending pharyngeal o Lovers – Lingual o Find – Facial o Old – Occipital o Positions – Posterior auricular o More – Maxillary o Stimulating – Superficial temporal ```

Question 430

Internal carotid

Answer 430

Passes through carotid syphon into brain, where it forms circle of Willis) arterial loop anastomosis) Branches:  Ophthalmic artery - Supplies structures of orbit  Posterior communicating artery - Acts as an anastomotic vessel Circle of Willis  Anterior cerebral artery Internal carotids then continue as middle cerebral arteries

Question 431

Name the arteries that supply the brain?

Answer 431

2 large carotid arteries (anterior) 2 smaller vertebral arteries (posterior)

Question 432

Branches of vertebral artery

Answer 432

* Meningeal branch – supplies the falx cerebelli, a sheet of dura mater * Anterior + posterior spinal arteries – supplies the spinal cord, spanning its entire length * Posterior inferior cerebellar artery – supplies the cerebellum

Question 433

Anterior cerebral artery syndrome

Answer 433

o Hemiparesis or hemiplegia contralaterally, involving primarily LLs + pelvic floor musculature o Sensory deficits contralaterally, involving leg + perineum o Apraxia (due to branches to supplementary motor area + corpus callosum) o Disconnection syndrome (due to callosal branches) o Anosmia (due to branches of the olfactory bulb + olfactory tract)

Question 434

Middle cerebral artery syndrome

Answer 434

o Hemiparesis or hemiplegia of lower half of contralateral face o Hemiplegia of contralateral upper + lower extremities o Sensory loss of contralateral face, arm, lego Ataxia of contralateral extremities o Aphasia: Broca's area, Wernicke's, Global aphasia - Result of a dominant hemisphere lesion (usually L brain) o Perceptual deficits: hemispatial neglect, anosognosia, apraxia, spatial disorganisation - As result of a non-dominant hemisphere lesion (usually the right brain) o Visual disorders: Contralateral homonymous hemianopia + Conjugate eye deviation – gaze preference towards side of the lesion

Question 435

Posterior cerebral artery syndrome

Answer 435

o Visual deficits: agnosia, prosopagnosia (face blindness), cortical blindness (w/ bilateral infarcts) o Contralateral homonymous hemianopia – examine via visual field testo Dyslexia o Involuntary movements: chorea, intention tremor o Contralateral hemiplegia (paralysis) o Weber’s syndrome: oculomotor nerve palsy o Bálint's syndrome: loss of voluntary eye movements optic ataxia, asimultagnosia

Question 436

How common are subarachnoid hemorrhages?

Answer 436

5% of all strokes

Question 437

How common are parenchymal (intracranial) haemorrhage strokes?

Answer 437

15% of all strokes

Question 438

How common are atherothromboemobilsms causing stroke?

Answer 438

50% of all strokes

Question 439

How common are intracranial small vessel disease and cardiac sources of embolism leading to stroke?

Answer 439

 Intracranial small vessel disease 25%  Cardiac sources of embolism 20%

Question 440

Symptoms of carotid artery occlusion

Answer 440

 Contralateral hemiplegia, hemisensory disturbance (blurring vision in ipsilateral eye)  Homonymous hemianopia (half vision lost, same side in both eyes)  Deterioration in consciousness level – because of increased intracranial pressure from large area of damage  Gaze palsy (eyes deviated to side of lesion)  Dominant hemisphere global aphasia  Expressive dysphasia (Broca’s) – difficult putting words together in meaningful way  Receptive dysphasia (Wernicke’s) – difficulty comprehension

Question 441

Symptoms of middle cerebral artery occlusion

Answer 441

 Contralateral hemiplegia, hemianaesthesia, hemianopia  Dominant hemisphere – aphasia, acalculia, agraphia, alexia  Non-dominant hemisphere – sensory neglect, dressing apraxia, failure to recognise faces

Question 442

Symptoms of lacunar stroke?

Answer 442

 Pure motor stroke – contralateral loss of power  Pure sensory stroke – contralateral loss of light touch + proprioception  Dysarthria – slurred speech  Ataxic hemiparesis  Sensorimotor stroke

Question 443

Symptoms of posterior circulation occlusion. Occlusion in vertebral, basilar, posterior cerebral arteries (supply brainstem, cerebellum, posterior occipital lobe)

Answer 443

 Vertigo – damaged to CN VIII --> N+V  Ataxia – balance problems  Paresis – motor tracts  Paraesthesia – sensory tracts  Isolated hemianopia  Branch occlusion

Question 444

Dural reflections

Answer 444

* In some areas within skull, meningeal layer of dura mater folds inwards as dural reflections * They partition brain + divide cranial cavity into several compartments; example: Tentorium cerebelli - tough connective tissue

Question 445

Brain injury can be specific to one area (focal) or affect large area of brain (diffuse). What is focal primary brain injury?

Answer 445

o Contusion (bruised brain) – coup + contrecoup o Haemorrhage o Skull fractures o Penetrating head injury

Question 446

What is diffuse brain injury?

Answer 446

o Diffuse axonal injury – damage to the white matter of brain o Hypoxic brain injury - brain can be diffusely injured secondary to hypoxia o Diffuse brain swelling o Concussion

Question 447

What is secondary brain injury?

Answer 447

 Occurs immediately after trauma + produces effects that may continue for a long time  This can be prevented, unlike primary injury

Question 448

Examples of secondary brain injury

Answer 448

* Raised ICP – worsens the primary damage * Hypoxic brain injury * Ischaemic brain injury * Seizures * Infection * Brain herniation * Cerebral oedema * Hydrocephalies * Chronic traumatic encephalopathy

Question 449

What is progressive brain damage?

Answer 449

 This may develop after initial injury  They are a chain of events that occur in primary brain injury + are worsened by increased ICP + reduced perfusion

Question 450

What is a normal ICP?

Answer 450

7-15mmHg for a supine adult o 10mmHg – normal o >20mmHg – abnormal o >40mmhg – severe

Question 451

Extradural haematoma (lemon)

Answer 451

 White lens shape - Blood outside of dura (middle meningeal artery which sits around the temporal side of head)  Trauma to temporal part of head may cause middle meningeal artery to rupture  Falx cerebri has been pushed over to side  Severe mass effect from this extra-dural haematoma

Question 452

Subdural haematoma (banana)

Answer 452

 Slower bleed  Bi-convex shape  Bleed below dural layer (usually venous)  More likely to happen in older people (brain shrinkage to age and dehydration)  Mass effect - Midline shift and effacement of lateral ventricle (pushed onto other side, brain squashed)

Question 453

Emergency response of head injured patients

Answer 453

Airway (with cervical spine control):  Can be blocked with food, etc.  Unconscious person - Jaw may drop back and block airway  Injured brain sensitive to hypoxia so airway must be managed (must be put on a ventilator if GCS score 8 or below) Breathing:  Keep oxygenation  Collapsed lungs, etc. Circulation:  Make sure bleeding is stopped and blood replaced  Healthy people - aggressive resuscitation is very important  Elderly people - Not always carried out because other factors involved  Cerebral blood flow (CBF) = Mean arterial pressure (MAP) - Intracranial pressure (ICP) Management:  ABC  Treat threats to life  Normalise oxygenation, ventilation and circulatory status

Question 454

PET

Answer 454

``` o Lengthy process o Preparation time needed o Invasive - Uses radioactive tracer o Very expensive o Poor spatial resolution o Very high sensitivity o Established clinical tool o Typically used for oncology o Only one research scan per lifetime for volunteers ```

Question 455

EEG

Answer 455

``` o Lengthy process o Lots of preparation time needed o Electrical activity on scalp generated from neural activity o Very cheap o Portable o Good time resolution o Poor spatial resolution o Clinically established o Data is very noisy ```

Question 456

MEG

Answer 456

``` o Much quicker than EEG o Little preparation time needed o Magnetic fields on scalp generated from neural activity o Entirely passive o Expensive o Good time resolution o Good spatial resolution o New clinical tool o Data interpretation is complicated ```

Question 457

MRI

Answer 457

o Relatively quick o Little preparation time needed o Moderately expensive o Poor time resolution o Good spatial resolution o Variety of contrast regimes o Established clinical tool o Sensitivity is poor o Many different applications

Question 458

CT and XR

Answer 458

o Very quick processes o Little preparation time is neededo Relatively cheap o Good for hard tissue (bone) o Poor for soft tissue (brain) o Use ionising radiation o Clinically established

Question 459

Symptoms of Alzheimer's disease

Answer 459

 Insidious onset, gradual progression  Memory loss – Initially short-term memory, later global  Language impairment, loss of coherent speech and eventually mutism  Decline in motor skills + ADL (dressing, mobility)  Loss of recognition skills - Objects, people, themselves  Disorientation – Can get lost in familiar places and get disorientated about time  Altered personality e.g. apathy, irritability, etc.

Question 460

On scan what is visible in Alzheimer's

Answer 460

 Diffuse cerebral atrophy • Especially medial temporal + parieto-temporal lobes  Ventricular dilatation, widening sulci, narrowed gyri  Temporal lobes are affected first, especially hippocampus

Question 461

What is visible by microscopy of brain in Alzheimer's?

Answer 461

Amyloid plaques + neurofibrillary tangles

Question 462

What are amyloid plaques?

Answer 462

* Abnormal processing of amyloid precursor protein leads to excess beta amyloid * Deposition of beta amyloid in/around nerve cells (senile/neurotic plaques) and cerebral arterioles (amyloid angiopathy) * Associated inflammatory response

Question 463

What are neurofibrillary tangles?

Answer 463

* Formed from abnormally phosphorylated tau proteins | * Which disrupt cerebral architecture + functioning

Question 464

Treatments of Alzheimers?

Answer 464

Acetylcholinesterase inhibitors (AChEI). N-methyl D-aspartate (NMDA) receptor antagonists.

Question 465

Acetylcholinesterase inhibitors (AChEI) | Alzheimer's disease treatment

Answer 465

* E.g. donepezil, galantamine, rivastigmine * Reduce breakdown ACh * Used in mild-moderate AD * 2/3 response with stabilisation or slight improvement over 6-12 months * Slow deterioration + institutionalisation

Question 466

N-methyl D-aspartate (NMDA) receptor antagonists | Alzheimer's disease treatment

Answer 466

* E.g. memantine * Reduce glutamate * Moderate-severe AD * May reduce behavioural symptoms/ delay institutionalisation * Benefit in other dementias unknown

Question 467

What is vascular dementia (20-30% of all dementia) caused by?

Answer 467

Caused by disease/injury affecting vasculature of brain, typically involving a series of minor strokes

Question 468

Symptoms of vascular dementia?

Answer 468

 Small vessel disease (SVD) causes a type of vascular dementia with ischaemic changes * Insidious onset, gradual progression – slow than AD * Apathy/slowness of thought * Problems w/ executive functioning * Reduced attention * Relative preservation of higher cortical functions (gnosis, praxis, visuospatial)

Question 469

Treatment of vascular dementia

Answer 469

 Lifestyle changes – smoking, diet, alcohol, exercise  Control of blood pressure, cholesterol, diabetes  Aspiring, clopidogrel, warfarin

Question 470

Lewy body dementia

Answer 470

o Abnormal collection of Lewy body proteins in the wrong places o Primary symptoms: fluctuations in cognition/performance, visual hallucinations, parkinsonism

Question 471

Pathophysiology of lewy body dementia (10-15%)?

Answer 471

 Abnormal alpha-synuclein protein collection within the cytoplasm of neurons– Lewy bodies  Loss of dopamine-producing neurons in the substantia nigra, similar to Parkinson’s disease  Atrophy especially present in midbrain, temporal lobe, parietal lobe, cingulate gyrus

Question 472

Frontotemporal dementia 2-5%

Answer 472

o Mainly early onset <65 years old o 10% familial – mutation in tau gene (in microtubules) 3 common syndromes:  Dementia of frontal type – w/ emotional + behavioural changes due to frontal lobe atrophy.  Progressive non-fluent aphasia – progressive difficulty in language.  Semantic dementia – loss of knowledge of meaning of worlds/fluent aphasia. Pathology:  Unspecific  Pick type  Motor neuron disease

Question 473

Type of dementia

Answer 473

``` o Alzheimer's disease o Vascular dementia o Lewy body dementia o Frontotemporal dementia o Parkinson’s disease o Huntington’s disease o Creutzfeldt-Jakob disease o MS ```

Question 474

Medical management of dementia

Answer 474

o Review of physical health + medication o Exclude alcohol, pain, co-morbid depression/anxiety, etc. o ABC/Behavioural Approach Drug management:  Symptomatic treatments e.g. antidepressants, anti-psychotics, etc.  Disease modifying treatments e.g. AChEI

Question 475

Risks of general anaesthetic

Answer 475

* Airway problems (lose reflexes) * Aspiration * CNS, CVS, RS – depression * Awareness (if not enough anaesthesia) * Post-operative nausea + vomiting * Death – extremely rare

Question 476

What are these? Tubocurarine. Atracurium.

Answer 476

Neuromuscular blocking agents - antagonists o Non-depolarising + competitive o Block stimulation of muscles by competitively blocking the binding of ACh to its receptors o Reversed by acetylcholinesterase inhibitors

Question 477

What is suxamethonium? Suxamethonium:  The only depolarising neuromuscular blocking agent used clinically  Has rapid onset (30 seconds) but v. shot duration of action (5-10 mins) due to hydrolysis by various cholinesterases

Answer 477

Neuromuscular blocking agents - agonists o Depolarising + non-competitive agent o Depolarise muscles to a point where they can no longer be stimulated o Have prolonged effects under the influence of acetylcholinesterase inhibitors

Question 478

Epilepsy

Answer 478

 60% of individual w/ epilepsy have partial seizures  60-70% of partial seizures originate in temporal lobe  60-70% of patients become seizure free after treatment w/ anticonvulsant

Question 479

Stroke classification

Answer 479

TACI (Total Anterior Circulation Infarct) o Hemi motor + sensory deficit o Hemianopia o Cortical dysfunction PACI (Partial Anterior Circulation Infarct) o Any 2 of the above or isolated cortical dysfunction LACI (Lacunar Circulation Infarct) o Pure motor hemiplegia o Pure sensory loss o Motor + sensory loss POCI (Posterior Circulation Infarct) o Vision related because occipital infarct o Vertigo, diplopia, ataxia

Question 480

2 types of nociceptive pain

Answer 480

Somatic - localised + easy to describe Visceral - poorly localised, associated with autonomic changes

Question 481

2 cells in synovium

Answer 481

Type a - macrophage derived Type b - fibroblast-derived

Question 482

Pseudogout

Answer 482

Calcium pyrophosphate deposition (CPPD) disease. A type of arthritis that causes spontaneous, painful swelling in joints.

Question 483

4 most common fracture sites from a fall

Answer 483

Distal radius Vertebra Proximal femur Proximal humerus

Question 484

Classic clinical feature of hip fracture?

Answer 484

Shortened and externally rotated leg

Question 485

Ways to classify hip fractures on xray?

Answer 485

Intra-capsular. Intra-trochanteric. Extra-capsular. Intracapsular much more likely cause of avascular necrosis than extracapsular.

Question 486

What is spina bifida?

Answer 486

Posterior spine elements (lamina, facets + spinous processes) fail to develop, allowing the contents of the spinal cord to prolapse through the defect

Question 487

What is the medullary cavity found in long bones composed of?

Answer 487

Yellow fatty marrow or red haematopoietic marrow (children)

Question 488

Describe the inner surface of the endosteum (of bones)

Answer 488

Inner surface is lined by a layer of flattened cells

Question 489

Which word describes this: thin vascular membrane of connective tissue that lines the inner surface of the bony tissue that forms the medullary cavity of long bones

Answer 489

Ednosteum

Question 490

Where does the cortical/compact bone layer lie relative to the trabecular/cancellous bone layer?

Answer 490

Compact bone is the outer layer Trabecular bone is the inner layer

Question 491

What is the periosteum?

Answer 491

A connective tissue membrane surrounding the bone

Question 492

What is endochondral ossification?

Answer 492

The cartilage is removed and replaced with bone. It occurs in the skeleton from the second month of intrauterine life

Question 493

Where does long bone growth occur?

Answer 493

From the physis. It occurs by endochondral ossification of the cartilage continually produced by the cells of the physis

Question 494

What happens when long bone growth ceases?

Answer 494

Epiphyseal bones + metaphyseal bone fuse

Question 495

What is the blood supply of bone?

Answer 495

Partly from a nutrient artery which penetrates though a nutrient foraemen via a vascular network in the periosteum. There is also an intramedullary component

Question 496

What word describes the following - lateral deviation of spine in the coronal plane associated with rotation?

Answer 496

Scoliosis

Question 497

What word describes the following - increased posterior convexity of spine in the sagittal plane?

Answer 497

Kyphosis

Question 498

What word describes the following - increased anterior convexity of spine in the sagital plane?

Answer 498

Lordosis

Question 499

How many vertebrae are there?

Answer 499

Cervical 7 Thoracic 12 Lumbar 5 Sacrum 5 - fused Coccygeal 3-5 fused

Question 500

Which nerve may be damaged by a fracture of the medial epicondyle

Answer 500

Ulnar nerve - it passes the medial epicondyle posteriorly