Neuro Ddx Flashcards
What is the scale for grading reflexes?
0 No response
1+ Diminished
2+ Normal
3+ Brisker than average, increased
4+ Hyperactive, very brisk, with clonus (involuntary rhythmic oscillations between flexion and extension)
Positive pronator drift indicates a lesion where?
contralateral corticospinal tract
note: even in the presence of overall normal strength, the presence of a pronator drift indicates that there is a lesion somewhere along the path of the pyramidal tract.
What does a positive pronator drift test look like?
affected arm starts to pronate and drift downwards, often with flexion at the fingers and elbow
What nerve root/muscle are you testing with strength of shoulder abduction?
C5, deltoid
What nerve root/muscle are you testing with strength of elbow flexion?
C5, C6, biceps
What nerve root/muscle are you testing with strength of elbow extension?
C6, C7, C8-triceps
What nerve root/muscle are you testing with strength of wrist extension?
C6-8, radial nerve
What nerve root/muscle are you testing with strength of wrist flexion?
C6, C7, median nerve
What nerve root/muscle are you testing with strength of finger extension?
C7-8, posterior interosseous nerve
What nerve root/muscle are you testing with strength of finger abduction?
C8, T1, ulnar nerve
What nerve root/muscle are you testing with strength of hand grip?
C7-8, T1
What nerve root/muscle are you testing with strength of thumb opposition?
C8, T1, median nerve
What nerve root/muscle are you testing with strength of hip flexion?
L2-4, iliopsoas
What nerve root/muscle are you testing with strength of hip extension?
S1, gluteus maximus
What nerve root/muscle are you testing with strength of hip adduction?
L2-4, adductors of hip
What nerve root/muscle are you testing with strength of hip abduction?
L4-5, S1, Gluteus medius and minimus
What nerve root/muscle are you testing with strength of knee extension?
L2-4, quadriceps
What nerve root/muscle are you testing with strength of knee flexion?
L4-5, S1-2, hamstrings
What nerve root/muscle are you testing with strength of ankle dorsiflexion?
L4-5, tibialis anterior
What nerve root/muscle are you testing with strength of ankle plantar flexion?
S1, S2, Soleus
What nerve root/muscle are you testing with strength of great toe dorsiflexion?
L5, S1, deep peroneal nerve
Which nerve roots involved in biceps reflex?
*C5*, C6
Which nerve roots involved in brachioradialis reflex?
C5, *C6*
Which nerve roots involved in triceps reflex?
C6, *C7*
Which nerve roots involved in patellar reflex?
L2, *L3*, L4
Which nerve roots involved in achilles reflex?
*S1*, S2
Draw out how to test extraocular movements. Which directions test each muscle? How are they innervated?
LR6SO4
Does CNIII constrict or dilate the pupil?
constrict
In a central CN VII lesion, which part of face is affected?
Lower face affected, upper half relatively spared
In a peripheral CN VII lesion, which part of the face is affected?
both upper and lower face are affected
Which tract carries touch, pain, temperature? Where do they cross?
Carried by the small fibers (c-fibers) which enter the lateral spinothalamic tract of the spinal cord and cross to the opposite side in front of the central canal 1 to 2 segments above the level of entry.
Which tract carries vibration and position sense? Where do they cross?
Carried by the large fibers which enter the posterior columns of the spinal cord and remain ipsilateral until they cross in the medulla.
Light touch tests which tract(s)
tests both the spinothalamic tract and the posterior columns
Pain/sharp testing assesses which tract?
spinothalamic
what physical exam finding is typical of distal stocking glove distribution neuropathies?
In patients with distal stocking glove distribution neuropathies, the sensation will become stronger as you move proximally.
temperature tests which tracts?
spinothalamic tracts
vibration tests which tract?
posterior columns
position sense/proprioception tests which tracts?
posterior columns
Mild distal vibratory loss can be a normal finding in people older than 65 and vibration sense continues to diminish each decade. Position sense should not change unless there is pathology in the dorsal root, dorsal root ganglion or the posterior columns.
what is the pattern of sensory loss for single peripheral nerve?
sensory loss in the distribution of the single nerve
what is the pattern of sensory loss of single nerve root?
sensory loss in a dermatomal distribution of the nerve root
what is the pattern of sensory loss for peripheral nerves (diffuse)?
stocking and glove type distribution
what are the sensory level anatomical landmarks?
- Clavicle: C5
- Nipples: T4-5
- Umbilicus: T10
- Inguinal ligament: L1
what do discriminative sensation tests assess for?
ability of the cortex to analyze and interpret sensations.
impaired stereognosis indicates lesion in ….
parietal and/or occipital lobes
impaired graphesthesia (number identification) implies lesion in …
parietal lobe
monofilament test assesses for …
peripheral neuropathy
The lateral cerebellar hemispheres represent the ________ and the central vermis represents the _______
The lateral cerebellar hemispheres represent the extremities and the central vermis represents the trunk
What findings would you expect on finger-to-nose and heel-to-shin testing in a pt with unilateral cerebellar lesions?
fluctuating velocity of movement and past-pointing on the same side
What findings would you expect in a pt with lesion in the vermis?
truncal and gait ataxia
What is dysdiadochokinesia?
inability to perform rapid alternating movements
what does the Romberg test assess?
posterior columns or proprioceptive function
Abnormalities in which functions may be associated with a positive Romberg test?
vestibular or cerebellar function
What does Spurling’s test assess for?
sensitive test for cervical radiculopathy (impingement on cervical nerve root, ex. impingement by herniated disc)
what does a positive Spurling’s test look like?
pain in affected nerve root distribution due to compression of neuroforaminae
What are the signs of C5 cervical radiculopathy?
Sensory: lateral elbow
Reflex decreased: biceps (C5/6)
Weakness: elbow flexion (biceps)
What are signs of C6 cervical radiculopathy?
Sensory: thumb
Reflex decreased: biceps (C5/6), brachioradialis (C5/6)
Weakness: elbow flexion (biceps), pronation (pronator teres)
What are signs of C7 cervical radiculopathy?
Sensory: 3rd finger
Reflex decreased: triceps (C7/8)
Weakness: elbow extension (triceps)
What are signs of C8 cervical radiculopathy?
Sensory: 5th finger
Reflex decreased: none
Weakness: finger flexion (flexor digitorum profundus)
What are the signs of T1 cervical radiculopathy?
Sensory: medial elbow
Reflex decreased: none
Weakness: 5th finger abduction (abductor digiti minimi)
what does the straight leg raise test assess for?
sensitive test for lumbar radiculopathy (impingement or irritation of a lumbar nerve root, ex. impingement by herniated disc)
what does a positive straight leg raise test look like?
pain in radicular pattern radiating into the ipsilateral lower limb
What are the signs of an L2 lumbosacral radiculopathy?
Sensory: anterior thigh
Reflex decreased: none
Weakness: hip flexion (iliopsoas)
what are the signs of an L3 lumbosacral radiculopathy?
Sensory: medial knee
Reflex decreased: patella
Weakness: knee extension (quadriceps)
what are the signs of an L4 lumbosacral radiculopathy?
Sensory: medial ankle
Reflex decreased: patella
Weakness: ankle dorsiflexion (tibialis anterior)
what are the signs of an L5 lumbosacral radiculopathy?
Sensory: dorsal foot
Reflex decreased: medial hamstring
Weakness: great toe extension (extensor hallucis longus)
what are the signs of an S1 lumbosacral radiculopathy?
Sensory: sole of foot
Reflex decreased: achilles
Weakness: plantar flexion (gastrocnemius)
what are the signs of an S2 lumbosacral radiculopathy?
Sensory: popliteal fossa
Reflex decreased: none
Weakness: none
what are some causes of central CN VII palsies?
stroke
tumor (in CNS from cortex to pons)
what are some causes of peripheral CN VII palsies?
Bell’s palsy (idiopathic or due to activation of HSV/VCV or Lyme or HIV)
otitis media
cholesteatoma
sarcoidosis
sjogren’s syndrome
tumor (in PNS from pons to face, ex. a parotid tumor)
where does the corticospinal tract decussate?
at caudal medulla at the pyramids
what is the function of the dorsal columns? is it ascending or descending?
ascending (sensory) pressure, vibration, fine touch, proprioception
where do the dorsal columns decussate?
in medulla
what is the function of the spinothalamic tract? is it ascending or descending?
ascending (sensory) lateral: pain, temperature anterior: crude touch, pressure
damage to corticospinal tract will cause function reduction/loss [above/below] lesion
below
UMN damage above crossover in medulla causes impairment on [same/opposite] side of body
opposite
UMN damage below crossover in medulla causes impairment on [same/opposite] side of body
same
UMN lesion signs
“everything up” increased: reflexes, tone
pos. Babinski (upgoing toes), spastic paralysis
can also have: weakness (not specific)
LMN lesion signs
“everything lowered” decreased: reflexes, tone
neg Babinski (downgoing toes), flaccid paralysis c
an also have: weakness (not specific), atrophy, fasciculations
