Neurology 4

Question 1

Musculocutaneous nerve function?
Motor
Sensory

Answer 1

Motor = Elbow flexion

Sensory = lateral part of FOREARM

Question 2

Flexion weakness at elbow - what nerve affected

Flexion weakness at wrist - what nerve affected

Flexion weakness at fingers - what nerve affected

Extension of elbow/wrist/fingers - what nerve affected?

Answer 2

Elbow = Musculocutaneous
Wrist = Median
Fingers = Median/ulnar

Extension weakness = Radial

Question 3

Median motor function?

Answer 3

Flexion of wrist and fingers ( except medial 2 fingers - Ulnar)

LOAF muscles
Lateral 2 lumbricals
Opponens pollicis brevis
Abductor pollicis brevis
Flexor pollicis brevis

Question 4

Ulnar nerve function

Answer 4

Finger abduction and adduction

Flexion of 4,5th digit = Flexor digitorum profundus

Question 5

Axillary nerve function?

Answer 5

Shoulder abduction

Question 6

Erb palsy - waiter’s tip lesion where and presentation?

Answer 6

C5-6 lesion
Loss of elbow flexion and shoulder movement
Sensory loss in lateral aspect of arm

Question 7

Klumpke palsy - lesion where and presentation?

Answer 7

C8 - T1 lesion

Supinated clawed hand + hyperextension at wrist

Question 8

Flaccid foot + Knee flexion = only 1 nerve cause this - name?

Answer 8

Sciatic nerve

Question 9

Once wallerian degeneration completes - denervated dying motor axon fibers express what?

Answer 9

Acetycholine - so inappropriate firing of motor in response to Ach = sign of denervation

Question 10

Neurogenic changes

morphology and recruitment of muscle unit action potential

Answer 10

surviving motor axons - tries to re-innervate died motor
-fibers = thin and unmyelinated
Longer/Broad/Polyphasic/ high amplitude!

Reduced recruitment!

Question 11

Myopathic changes

morphology and recruitment of muscle unit action potential

Answer 11

muscle fibers damaged + few remaining ( but are normal)

Small amplitude + normal/increased recruitment+ early

Question 12

AChr antibodies a/w what?

Answer 12

Thymoma and thymic hyperplasia

Question 13

Musk antibodies a/w what?

Answer 13

Generalized severe MG ( bulbar and respiratory involvement)

-young female - non white

Question 14

Singe fibre EMG best for?

Answer 14

Ocular MG

Question 15

Medications to avoid in MG?

Answer 15

Aminoglycosides
Tetracyclines
Macrolides
Fluoroquinolones
B-blockers

Question 16

Lambert-eaton syndrome?

Answer 16

Triad of ;
1 - proximal weakness (upper limbs most affected) - mild improvement post exercise
2- autonomic features - dry mouth/erectile dysfunction/urinary issues
3- areflexia ( post exercise)

NO SENSORY/ NO FATIGUABILITY

Question 17

Lambert-eaton syndrome a/w?

Answer 17

Paraneoplastic - SCLC

Non-paraneoplastic - HLA B8 DR3

Question 18

Lambert-eaton treatment?

Answer 18

Resect tumor

3-4 diaminopyridine - block K from going out - prolonged depolarisation

Question 19

Antibodies a/w Dermatomyositis and ILD?

Malignancy in ILD patients?

what Dermatomyositis antibodies associated with good response to treatment?

Answer 19

anti-MDA5 - rapidly progressive ILD
Anti-Jo 1 - ILD

Lower risk

Anti-MI 2

Question 20

Treatment for dermatomyositis?

Answer 20

Prednisolone (iv methylprednisolone if severe weakness)

CYP if ILD

Question 21

SLCO1B1 gene function?

Answer 21

uptake of statin into liver cells

Question 22

Necrotizing autoimmune myopathy antibodies?

Answer 22

anti-SRP/anti-HMG COA

high CK

Question 23

Anti-SRP a/w?

Answer 23

Dilated cardiomyopathy

No response to immunosuppression

Question 24

Anto-HMG COA a/w?

Answer 24

higher levels of CK and muscle weakness severity
HIGHLY SPECIFIC FOR NECROTIZING AUTOIMMUNE MYOPATHY
-can occur without statins

Question 25

Signal recognition particle is what?

Answer 25

Peptide involved in transport protein to endoplasmic reticulum

Question 26

Commonest myopathy > 50 yrs old?

Answer 26

Inclusion body myositis ( distal + asymmetric weakness)

Question 27

what muscle is spared in IBM quadriceps weakness?

Answer 27

Rectus femoris

All the vastus muscle affected-atrophy

Question 28

Perimysial,endomysial inflammation and necrosis - have upregulation of what?

Answer 28

MHC1 - CD8 complex

Question 29

Anti-synthetase syndrome is what?

Answer 29

Myositis with;
ILD
Mechanic hands and polyarthritis
Fever
Raynaud's

Question 30

Myopathy in ;
Hypothyroidism features?

Hyperthyroidism features?

Answer 30

• Symmetric PAINFUL muscle cramps, weakness
• occasional HIGH CK
• Delayed reflexes
• PAINLESS muscle weakness
• NORMAL CK
• brisk reflexes

Question 31

Statin induced NAM - HLA antibodies
protective?
at risk?
association with SLCO1B1 gene?

Answer 31

At risk - HLA DRB1 11

Protective - HLA DQA1/ DQB6

No! SLCO1B1 only for Statin myopathy