Exam 2 Flashcards
What are multimodal sensations?
Combination of both superficial and deep sensations that are subject to integration with higher cortical functions and memory
Where is the association cortex for somatosensory, visual and auditory functions?
Inferior parietal lobe
The inferior parietal lobe is the association cortex for what 3 multimodal sensations?
Somatosensory, visual, and auditory
Stereognosis test
Patient identifies object in hand
Barognosis test
Patient assess relative weight of similar shape and size object in hands
Topognosis
Touch patient on their skin and ask them to point to the spot you just touched
Graphognosis
Write a letter or number on patients chest, back or palm and have them identify it
2 point discrimination and normal measurements
Determine at what distance a patient can determine 2-point discrimination
Finger tips: 2-4mm
Dorsum of finger: 4-6mm
Palm: 8-12mm
Dorsum of hand: 20-30mm
Somatognosis?
Patients ability to know a body part is their own
Nosognosis:
Ability of patient to know that he is ill
Ex: hemiplegia, patient believes they are healthy
Aka for graphognosis
Graphesthesia
Problems with sterognosis, barognosis, topognosis, graphognosis, 2 point discrimination, somatognosis or nosognosis would indicate an issue where?
Association cortex in the inferior parietal lobe
Somatic sensation is conscious perception of what 5 things?
Touch Pain Temperature Vibration Proprioception
What are the two main somatosensory systems?
Posterior column pathways
Anterolateral pathway
What sensations does the posterior column pathway mediate?
Proprioception
Vibration
Fine, discriminative touch
What sensations do the anterolateral pathways mediate
Pain
Temperature
Crude touch
What sensations does the lateral spinothalamic pathway mediate?
Superficial pain
Temperature
(Pinch your lateral neck it hurts)
What sensations does the anterior spinothalamic tract mediate?
Crude touch
Could be very crude and touch your anterior
Pathway of posterior columns
Stimuli carrie
Posterior columns pathway: stimuli is carried by _____ ____ neurons and enter the ____ ______ via the ____ _____ ____. From here it ____ the spinal cord ______ in _____ _____.
Primary sensory Spinal cord Dorsal root ganglion Ascends Ipsilaterally Posterior columns
After ascending the spinal cord ipsilaterally in posterior columns it synapses in ____ ____ nuclei with secondary axons that then _____ and _____ in the ____ ______. From here it synapses in the _____ and is distributed to ____ ____ _____
Posterior column nuclei
Synapse and ascend in the medial lemniscus
Thalamus and is distributed to primary somatosensory cortex
What kind of findings are seen in posterior column pathway lesions
Ipsilateral
Pain, temperature and crude touch are carried by ___ _____ neurons and enter the spinal cord via ___ ___ ____. From here they synapse with ___ ____ neurons immediately in ___ _____ of the spinal column. From here they _______ and ascend in the ____ _____. Then it synapses in the ____ and is distributed to ____ ____ cortex
Primary sensory
Dorsal root ganglion
Secondary sensory neurons in gray matter
Deccussate and ascend in the spinothalamic tract
Synapse in thalamus and distribute to somatosensory cortex
Sensation with posterior column lesion
Tingling, numb
Sensation with anterolateral lesions
Sharp, burning, or searing pain
Sensory loss can be caused by lesions where
Peripheral nerves Nerve roots Posterior columns Anterolateral pathways Thalamus Primary somatosensory cortex
Sensations in spinothalamic tract
Light touch
Sharp
Temperature
Sensations in dorsal columns
Vibration
2 point discrimination
Proprioception
Superficial sensory examination aka?
Exteroceptive/cutaneous examination
What is part of the superficial sensory examination
Light touch
Pain
Temperature
What is tested in light touch examination
Anterior spinothalamic tract
Tactile disc of merkle
Testing dermatomes
What is a dermotome
Area of skin innervation by a single spinal nerve
What does the sharp touch examination test
Lateral spinothalamic tract
What does temperature examination test
Lateral spinothalamic tract
Unnecessary if pain is fine—why it is rarely performed
-better at localizing area of dysfunction
Allogynia
Painful sensations provoked by normally non-painful stimuli
Anesthesia/analgesia
Absence of all sensation/pain
Dysethesia
Unpleasant, abnormal, or painful sensation
HYPESTHESIA/hypoesthesia
Decreased sensation
Hyperesthesia
Increased sensation
Paresthesia
Abnormal sensation
Myelo-
Spinal cord
Radiculo-
Nerve root
Neuro-
Nerve
General presentation of myelopathy
Pain: neck, arm, lower back, leg
Usually bilateral
Sensation: abnormal pattern
General presentation of radiculopathy
NR
Pain: dermatomal
Usually unilateral
Sensation: dermatomal
General presentation of neuropathy
Pain: follows nerve distribution
Usually unilateral
Sensation: peripheral nerve distribution
Common causes of compression
Disc hernation DJD Trauma Inflammatory changes Tumors
Posterior cord lesion causes and characteristics
Vibration and position sense loss at injury site and distal
Due to: Trauma Compression from tumors MS B12 deficiency and tables dorsalis
Most common cause of radiculopathy
Disc derangement
Pressure from IVF narrowing
Compression of a dorsal nerve root
Radiculopathy
Characteristics of radiculopathy
- Numbness and tingling
- Loss of vibration and position sense
- Hyporeflexia with NO muscle atrophy (NO input of stretch but muscle shortens/lengthening normal)
- sensory loss dermatomally
- LMNL characteristics of reduced strength, reflexes, sensation
What may cause numbness and tingling, loss of vibration or position sense, hyporeflexia, sensory loss in dermatomes, LMNL characteristics of reduced strength, reflexes and sensation?
Compression of dorsal nerve root—Radiculopathy
Mononeuropathy characteristics
Unilateral loss in distribution of peripheral nerve
Sensory lost first (vibration often earliest affected)
DTR depressed
MC causes of mononeuropathy
Trauma
Autoimmune
Polyneuropathy characteristics
Bilateral loss in glove and stocking distribution
- sensory lost first (vibration) & LONGEST nerves affected first
- DTR depressed
MC causes of polyneuropathy
- DM
- malnutrition of alcoholism
- Lyme disease/inflammatory/autoimmune conditions
What tissues are devoid of nociceptos
Articulate cartilage
Inner annulus and nucleus of intervertebral disc
Synovial membranes
What are mechanical noxious stimuli
Acute trauma
Repetitive microtrauma
Subluxation complex
Thermal noxious stimuli
Exposure to excessive heat/cold
Chemical noxious stimuli
- histamine
- prostaglandins
- plasma kinins
- potassium
- serotonin
- substance P—released directly from damaged tissue
Type A Delta fibers characteristics and what they relay?
Lightly myelinated
Relay a sharp, stinging sensation
Type C pain transmission and characteristics
Unmyelinated
Aching, burning type of pain
Common causes of neuropathic pain
Diabetes
Postherpetic neuralgia
Phantom limb
Trigeminal neuralgia
Recurrent meningeal nerve aka?
Sinuvertebral nerve
What does the sinuvertebral nerve/recurrent meningeal nerve innervate?
Outer third of annulus fibrosis posteriorly
PLL
Dura
What is the significance of the sinuvertebral nerve related to neuropathic pain
Nocioceptive nerve endings within annulus fibrosis of disc. Annular tears can cause low back pain, and in buttocks, SI, and lower region
Nerve root irritation cause
No direct compression of NR
Inflammatory response of disc injury that causes pain
Cause of NR compression
Direct compression of NR
Presentation of NR irritation
Dermatomal pattern
Hyperesthesia
Increased sympathetics—> vasoconstriction (hypothermia)
Sensory, motor, DTR often normal
Presentation of NR compression
Pain, numbness in dermatomal pattern
Hypoesthesia
Decreased sympathetics—> vasodilation (hyperthermia)
-sensory, motor and DTR have decreased findings
Particular dermatomal or paraspinal level of ______ often correlates with area of what?
Hyperalgesia
Primary spinal subluxation
Cool info: sharpless demonstrated that minuscule amounts of pressure on a NR equivalent to a feather falling on your hand can cause up to a 50% decrease in electrical transmission down the course of the nerve
Wow!
If compression at c5 IVF….what disc/NR?
C6 NR
C5 disc
If compression at C5 disc…IVF/NR?
C5 IVF
C6 NR
If T7 IVF compressed what NR and disc involved?
T7 NR
T7 disc
If L5 IVF compressed what disc/NR involved?
L4 disc
L5 NR
If L4 disc herniated what IVF/NR involved?
L5 NR/IVF
Motor pathway?
Cortex…..
Brainstem……cerebral peduncle….pyramids (points of crossing)
Spinal cord……lateral corticospinal tract, anterior horn, alpha motor neuron
Peripheral NS…..target muscle
From the motor cortex, the motor pathway descends through the ______ _____ and then through the _____ where they ______. From here they enter the spinal cord and ______ in the ____ ______ _____ and synapse in the ____ ____ with __ ______ neurons. From here the neurons target the ________
Cerebral peduncles
Pyramids where they decussate
Descend in the lateral corticospinal tract
Synapse in the anterior horn with alpha motor neurons
Target the muscle
Motor pathway lesions would show what kind of findings?
Ipsilateral UMN Contralateral LMN (spinal cord)
0/5 grade of muscle
Complete paralysis
1/5 muscle testing
A twitch of muscle
0-10% of movement
Doctor can feel action but no movement
2/5 muscle testing
Active movement available with no gravity
11-25% of normal movement
3/5 muscle test
Active movement against gravity
26-50% of normal movement
4/5 muscle testing
Movement against gravity and mild resistance
51-75% normal movement
-resistance of two fingers
5/5 muscle testing
76-100% normal movement
Increased muscle tone indicates what?
UMNL
Decreased muscle tone indicates what?
LMNL
Hypertonic
Increased muscle tone
TWO TYPES
What are the two types of hypertonia?
Spasticity
Rigidity
Spasticity
Hypertonia most near middle of ROM
Apparent with fast passive ROM
VELOCITY DEPENDENT (seen with rapid movements)
Lesions of pyramidal tract (corticospinal)
—-seen with stroke, spinal cord compression, motor neuron disease
More tone in initial part of movement aka “clasped knife phenomenon”
What type of hypertonia is more apparent with fast passive ROM and is velocity dependent?
Spasticity
Lesions of where lead to spasticity?
Pyramidal tract—aka corticospinal tract
Lesions in the pyramidal tract—corticospinal tract cause what?
Spasticity
What may cause a lesion of the corticospinal tract that may lead to spasticity?
Stroke
Spinal cord compression
Motor neuron disease
Clasped knife phenomenon? Associated with?
More tone in initial part of movement
Spasticity
Characteristics of rigidity
Increased tone throughout passive ROM Same resistance in all directions Independent of speed of movements Seen in extrapyramidal lesions (Parkinson’s) 2 subtypes: cog wheel, lead pipe
What type of hypertonia is seen with increased tone through passive ROM and is independent of speed of movement?
Rigidity
A lesion where may lead to rigidity?
Extrapyramidal lesions
Lesions in extrapyramidal tract may cause what type of hypertonia?
Rigidity
What are the two subtypes of rigidity?
Cog wheel and lead pipe rigidity
What may cause a lesion in extrapyramidal tract that leads to rigidity?
Parkinson’s
Hypotonia? Indicative of?
Decreased muscle tone
Issues at level of reflex arc aka LMNL
What may cause neural shock
Severe upper motor neuron damage in brain or spinal cord
Cerebral shock and spinal shock
What is unique of neural shock in regards to it’s presentation?
Peripheral symptoms first noted even though its an UMNL
Deficit in regards to reflexes
Loss of normal neurological function
Reduced muscle tone, stretch, reflexes, strength, volume
LMNL
Release in regard to reflexes
Exaggerations or perversions of normal function due to loss of cortical inhibition
**inhibition normally there so that you don’t have crazy reflexes and kick people
Hyperreflexia, hypertonia, and pathologic reflexes
Lesions where in reflex deficit?
LMNL
Lesions where in release reflex
UMNL
Findings in deficit reflexes
Reduced muscle tone, strength, reflexes, strength, volume
Findings in release reflexes
Hyper-reflexia, hypertonia, pathologic reflexes
0-1 reflex grade indicative of what?
LMNL
3-4 grade reflex indicative of what?
UMNL
Grading reflexes aka?
Wexler scale
Jendrassik Maneuver
Distractions given such as clenching fist, wiggling toes, etc.
Done when reflexes appear to be diminished or absent with no other neurologic findings
Clonus
Involuntary rhythmic contractions when sudden passive stretch of muscle occurs
Clonus often seen with what other findings
Spasticity and hyperactive DTRs in corticospinal tract disease
Pathway of superficial reflexes
Sensory signal reaches spinal cord, ascend, reach brain, motor limb descends cord to reach neurons
What can cause a + superficial reflex?
Severe LMNL or destruction of sensory pathways from skin that’s stimulated
Spinal cord damage (UMNL)
LMNL cause _____ DTRs, _______ superficial reflexes
UMNL cause _____ DTRs, and ______ superficial reflexes
Decreased, absent
Increased, absent
What are the 10 superficial reflexes
Gag reflex Corneal blink reflex Epigastric Upper abdominal Middle abdominal Lower abdominal Cremasteric reflex Gluteal reflex Plantar reflex Anal
Innervation of cremasteric reflex
L1-L2
Ilioinguinal, genitofemoral nerves
Female version of cremasteric reflex
Geigel reflex
Normal finding in plantar reflex
Plantar flexion of toes and foot
+ finding of plantar reflex
Dorsiflexion of great toes and flaring of the other toes
Anal reflex innervation
S2-S5
Hemorrhoidal
What controls/inhibits pathologic reflexes
Motor cortex
Pyramidal tracts
Timeline of findings in UMNL?
- Increased DTR
- Absent superficial
- Pathological reflex
When are pathological reflexes considered normal?
Infants-6mo
2 years for babinski
What is one of the most significant indications of disease of corticospinal system at any level from motor cortex through descending pathways?
Babinski sign?
What innervations are tested with pupillary light reflex?
Afferent: CN2
Efferent CN3
Accommodation reflex tests what?
CN 3
Ciliospinal reflex tests what?
Afferent: cervical pain fibers c8-t2 and CN5
Efferent: cervical sympathetics
What is normal finding in ciliospinal reflex?
1-2mm dilation
Oculocardiac reflex tests? Normal finding?
Afferent: CN 5
Efferent: CN 10
Decreased heart rate and BP noticed where thumb is pressed on eyeball
Carotid sinus reflex tests, normal?
Afferent: CN 9
Efferent: CN 10
Decreased heart rate and fall in BP when press carotid sinus
Bulbocavernosus reflex tests? Normal?
S3-s4
Contraction of bulbocavernosis muscle and urethral constriction and anal sphincter contraction when stroke, pinch, or prick the dorsum of the glans of the penis?
Reflex dysfunction of the muscle
Stretch reflexes are depressed in parallel to loss of strength
Reflex dysfunction of neuromuscular junction
Stretch reflexes are depressed in parallel to loss of strength
Reflex dysfunction of peripheral nerve
Stretch reflexes are depressed usually out of proportion to weakness
Bc afferent arc is involved early in neuropathy
Reflex dysfunction in nerve root
Stretch reflexes depressed in proportion to contribution that root makes to the reflex
- superficial reflexes are rarely depressed since many overlap
- extensive damage can depress reflex in proportion to amount of sensory loss in dermatomes tested or motor loss in involved muscles
Reflex dysfunction and spinal cord and brainstem
Stretch reflexes are hypoactive at the level of lesion and hyperactive below lesion
Superficial reflexes are hypoactive at and below level of lesion and normal above
Reflex dysfunction in cerebellum
Lesions don’t have large affect on stretch reflexes
Reflex dysfunction and basal ganglia
No consistent DTR or superficial reflex changes
May see “primitive reflexes” associated with diffuse cerebral dysfunction (Dementia)
Reflex dysfunction and cerebral cortex
Unilateral disease affecting motor cortex will give UMN pattern of weakness: hyperactive muscle stretch reflexes and depressed or absent abdominal and cremasteric reflexes on contralateral side
-babinski response possible
-bilateral damage to motor cortex inhibitory control causes emotional expression reflexes to be defective
——-cry or laugh with little cause and don’t understand why they are laughing/crying
————-responses are released in “pseudobulbar” pattern
Presentation of transverse cord lesion
Partial/complete interruptions to all motor/sensory paths
Diminished sensation in all dermatomes below lesion
Weakness/reflex loss pattern helpful to determine location of lesion
Causes: trauma, tumor, MS, transverse myelitis
What may cause transverse cord lesion
Trauma
Tumor
MS
Transverse myelitis
Presentation with hemicord lesion aka?
Brown-square syndrome
Ipsilateral UMN weakness due to lateral corticospinal tract damage
Ipsilateral vibration and joint position (dorsal column)
Contralateral loss of pain and temperature (ant/lat spinothalamic)
Causes: penetrating injuries, MS, lateral compression from tumors
What may cause brown-sequard syndrome?
Penetrating injuries
MS
Lateral compression from tumors
Presentation of central cord lesion-small
- sensory fibers crossing from spinothalamic tract injuries
- pain and temperature loss
- cape distribution in Cervicals
Presentation of central cord lesions-large
Anterior horn cells damaged leading to lower motor findings at level of lesion
Corticospinal tract damaged leaded to UMN signs
Posterior columns: vibration/position affected
Below lesion:
Vibration, position, pain, temp, motor losses with small area of sacral sparing
Causes: syringomyelia, contusion, intrinsic cord tumors
What may cause a large central cord lesion
Syringomyelia
Contusions
Intrinsic cord tumors
Presentation of posterior cord lesion
Vibration and position sense loss at site and distal
Causes of posterior cord lesion
Trauma
Compression from tumor
MS
B12 deficiency and tabes dorsalis
Presentation of anterior cord lesion
Pain and temp loss distal to side (anterolateral)
Lower motor weakness at lesion (anterior horn cells)
UMN findings if lesion is large to impact corticospinal tract
Incontinence common as descending tracts controlling sphincter are primarily ventral cord
Cause: trauma, MS, anterior spinal artery infarct
What may cause an anterior cord lesion?
Trauma, MS, anterior spinal artery infarct
