Neurology Flashcards
Bells palsy
Acute, unilateral facial weakness or paralysis of rapid onset (<72h), none forehead sparing (ipsilateral)
Unknown cause
Associated with: dry eyes, inability to close eyes, dry mouth, hyperacusis (5%), pain when eating
Most tend to start getting better in 2-3wks
Full recovery expected in 3m
Conservative - eye lubricant, tape eye shut at night, wear sunglasses, avoid swimming/dusty areas. If affects eating - use a straw for drinking + soft foods
Medical - if presenting within 72h of onset - consider prednisolone
Acoustic neuroma
Benign tumour growing on the vestibulocochlear nerve
Adults aged 30-60
Sx: unilateral hearing loss, tinitus, vertigo, headaches
Tx: monitor, surgery to remove
Horners syndrome
Triad of: miosis, partial ptosis/enopthalmos, anhidrosis (ipsilateral loss of sweating)
Interruption to sympathetic nerves supplying the eye
*If arm, shoulder or hand pain then think Pancoasts tumour (apical lung tumour)
Causes of vestibulocochlear lesions
DM, MS, stroke, vasculitis, tumours, syphilis Acoustic neuroma Drugs e.g. aminoglycosides Noise damage Menieres disease (causes vertigo)
Bulbar palsy
Result of diseases affecting the lower CN (9-12) paralysis of muscles supplied by the medulla (tongue, pharynx, larynx, SCM, trapezius)
Causes: MND, brainstem tumours, CVA of brainstem, GBS, polio
Pseudobulbar palsy
Disease of the corticobulbar tracts bilaterally
Bilateral tract damage must occur
Inability to control muscles in your face
Peripheral neuropathy
Many conditions involving damage to the peripheral nervous system
- Motor
- Sensory
- Autonomic
Allodynia
Pain perceived following non-noxious innocuous stimulus (light touch stimulates pain)
Antalgia/antalgic
Pain provoked action
Hyperalgesia
Increased perception of pain
Parasesthesia
Abnormal sensations e.g. pins and needles
UMNL
Damage anywhere along the corticospinal tract - from cortex to anterior horn
Increased tone, pyramidal weakness, increased reflexes, clonus, generally less wasting than lower, babinski is upgoing
LMNL
Damage from anterior horn distally Pattern of weakness corresponds to the muscle affected Wasting + fasciculation Areflexia Hypotonia Normal babinski
Muscle weakness grading (MRC power scale)
0 = no contraction 1 = flicker of contraction 2 = some active movement 3 = active movement against gravity 4 = active movement against resistance 5 = normal power
Which hand nerves innervate which hand muscles?
Thenar eminence = median nerve
Hypothenar eminence = ulnar nerve
Interossei = ulnar nerve
*radial nerve just has sensory innervation to the hand - dorsal surface of lateral 3 and half digits (thumb side)
Sensory innervation to the hand
Medial 1 and 1/2 fingers = ulnar
Lateral 3 and 1/2 fingers = median
Dorsal side of lateral 3 and half fingers = radial
Median nerve mononeuropathy (C6-T1)
Carpal tunnel (compression of median nerve as goes through the carpal tunnel in the wrist) or trauma
LLOAF - 2 lumbricals, opponens pollicis, abductor pollicis brevis, flexor pollicis brevis
+ thenar wasting
Sensory loss over radial 3 and half fingers and palm
Aching pain in hand esp at night - relieved by dangling hand over bed + shaking it ‘wake + shake’
Tinels and phalens +ve
Ulnar nerve mononeuropathy (C7 - T1)
Result of elbow trauma
Weakness/wasting of ulnar side (medial side)
Hypothenar wasting
Interossei wasting (can’t cross fingers in good luck sign)
Medial 2 lumbricals so claw hand
Sensory loss over medial 1 and 1/2 fingers
Radial nerve mononeuropathy (C5-T1)
May be damaged by compression against the humerus
This nerve opens the fist
Sensory loss is variable - most reliable is loss over anatomical snuffbox
Test for wrist and finger drop
Causes of carpal tunnel syndrome
Anything causing swelling/compression of the tunnel: pregnancy, myxoedema, acromegaly, myeloma, local tumours, RA, amyloidosis
Brachial plexus mononeuropathy
Pain/parasthesiae + weakness in affected arm in variable distribution
Causes: trauma, radiotherapy for BC
Phrenic (C3-C5) mononeuropathy
Lesions cause orthopnoea + raised hemidiaphragm on CXR
Causes: Lung Ca, TB, paraneoplastic syndromes, myeloma
Lateral cutaneous nerve of the thigh (L2-L3)
Entrapment under inguinal ligament - anterolateral burning thigh pain
Sciatic mononeuropathy (L4-S3)
Causes: pelvic tumours or fractures
Hamstrings and all muscles below knee affected (foot drop) with loss of sensation below knee
