Neurological assessment Flashcards
Central nervous system (CNS)
- Brain and spinal cord
- Meninges; outer layer that covers the CNS to protect it
- Cerebrospinal fluid; nourish the brain and a cushion
Peripheral nervous system (PNS)
- Cranial nerves, spinal nerves and branches
- Sensory (afferent) messages to CNS
- Motor (efferent) messages from CNS
- 12 cranial nerves
- 31 spinal nerves and many branches
- Some nerves can be both sensory and motor (mixed nerves)
Cerebral cortex
Outer layer in humans, tightly folded, divided into 2 hemispheres (right/left)
Basal ganglia
Deep within the cerebral hemispheres, associated with motor movements (autonomic and occur involuntarily)
Thalamus
Relay station, all sensory information from the periphery to the cerebral cortex
Hypothalamus
Vital section, controlling body temperature, coordination HR, BP, helps regulate sleep , actions happen in the background (not conscious)
Pituitary gland
Regulated by hypothalamus, master gland of the body, below the hypothalamus, released many hormones that direct different processes
Cerebellum
Back of brain, maintains equilibrium, coordination/smoothing out of more complex movements, role in maintaining muscle tone
Brain stem
Part of brain right before the spinal cord, many fibre tracts that send message to/from the brain, coordinated vital centre activity (HR, BP, respirations)
Spinal cord
Long structure that runs down column, continuous with brains stem, down until L1-L2, highway for motor/sensory messages, ascending/descending tract, nerve conduction
Frontal lobe
- Personality
- Behaviour
- Emotion
- Intellectual functions
Broca’s area
- In frontal lobe
- Motor speech
- Expressive aphasia; if injured cannot say words
Temporal lobe
- Hearing
- Taste
- Smell
Wernicke’s area
- Temporal lobe
- Speech comprehension
- Receptive aphasia; if injuired cannot comprehend speech
Occipital lobe
- Visual reception
Parietal lobe
- Sensation
Precentral gyrus
- Primary motor area
- Near frontal and parietal lobe meeting (central sulcus)
Sensory pathways
- Up to brain
- Detect things in peripheral and send it to the brain
- Spinothalamic tract
- Posterior (dorsal) column
- Depends on type of message
Spinothalamic tract
- Pain
- Temperature
- Light (crude) touch
Posterior (dorsal) column
- Proprioception; where body parts are in relation to each other without visual aid
- Vibration
- Stereognosis; ability to identify familiar objects without visual aid
Motor pathways
- Descending path from brain to periphery
- Corticospinal (Pyramidal) tract
- Extrapyramidal tract
- Cerebellar system
Cortiospinal (Pyramidal) Tract
- Skilled, purposeful voluntarily movements
- Higher motor system
- Fine muscles tone
- i.e. playing the piano
Extrapyramidal tract
- Muscle tone
- Gross body movements
- Older more primitive system
Cerebellar system
- Coordinates movement
- Maintains equilibrium
- Posture
- Unconscious level
- Makes things smooth
Motor neurons
Upper motor neurons
- Located in the CNS
- Descending neurons
- Influence LMN
- i.e. stoke is a UMN disorder
Lower motor neurons
- Located in PNS
- Final pathway before innervating a muscle
- i.e. spinal cord lesion is . LMN disorder
Cranial nerces
- 12 Cranial Nerves
- Exit the brain rather than the spinal cord
- Mainly supply the head and neck (with a few exceptions)
- Can be sensory nerves, motor nerves, or both
Spinal nerves
- 31 pairs of spinal nerves
- Named for region of spine with there exit
- All mixed nerves – can sensory and motor impulses
Dermatomes
- Area on the skin that in innervated by one’s spinal nerve
- They overlap a little bit
Reflex arc
- PNS functioning
- Basic defence system of the body
Autonomic nervous system
Sympathetic nervous system - fight or flight
Parasympathetic nervous system - rest and digest
PNS afferent vs. efferent
Afferent
- Sensory division
- From sensory organs to brain
efferent
- Motor divison
- From brain to effectors
Cranial nerves
i - olfactory ii - optic iii - oculomotor iv - trochlear v - trigeminal vi - abducens vii - facial viii - acoustic ix - glossopharyngeal x - vagus xi - spinal accessory xii - hypoglossal
Cranial nerve i
- Olfactory
- Type: sensory
- Function: smell
Cranial nerve ii
- Optic
- Type: sensory
- Function: vision
Cranial nerve iii
- Oculomotor
- Type: mixed
- Function:
motor; most EOM movement, opening of the eyelids
parasympathetic; pupil constriction, lens shape
Cranial nerve iv
- Trochlear
- Type: motor
- Function: down and inward movement of the eye
Cranial nerve v
- Trigeminal
- Type: mixed
- Function:
motor; muscles of mastication
sensory; sensation of face and scalp, cornea, mucous membranes
Cranial nerve vi
- Abducens
- Type: motor
- Function: lateral movement of eye
Cranial nerve vii
- Facial
- Type: mixed
- Function:
motor; facial muscles, close eye, labial speech, close moth
sensory; taste (sweet, salty, sour, bitter) on anterior 2/3 of tongue
parasympathetic; saliva and tear secretion
Cranial nerve viii
- Acoustic
- Type: sensory
- Function: hearing and equilibrium
Cranial nerve ix
- Glossopharyngeal
- Type: mixed
- Function:
motor; pharynx (phonation and swallowing)
sensory; taste on posterior 1/3 of tongue, pharynx (gag reflex)
parasympathetic; parotid gland, carotid reflex
Cranial nerve x
- Vagus
- Type: mixed
- Function:
motor; pharynx and larynx (talking and swallowing)
sensory; general sensation from carotid body, carotid sinus, pharynx, viscera
parasympathetic; carotid reflex
Cranial nerve xi
- Spinal accessory
- Type: motor
- Function: movement of trapezius and sternomastoid muscles
Cranial nerve xii
- Hypoglossal
- Type: motor
- Function: movement of the tongue
Types of reflex arcs
1) Deep Tendon Reflexes (DTRs)
- i.e. hit tendon with a tool
2) Superficial Reflexes
- Exist within the skin
3) Visceral Reflexes
- Involuntary reflex that happen organically
4) Pathologic Reflexes
- Unexpected reflexive response
Neurological developmental considerations: infants
- Dramatic growth and development of neurological system during 1st year of life
- Initially, movements directed primarily by primitive reflexes
- Sensory and motor system develops during process of myelinization (helps transmit signals faster)
- Cephalocaudal (head to toe) and proximal to distal order
Neurological developmental considerations: older adults
- General atrophy; impaired fine coordination and agility, correction, and balance.
- Cranial/spinal nerves; velocity of nerve conduction decreases, slows reaction time in some individuals
- Sensory changes
- Motor system; slowing down of movement (motor system atrophy)
- Progressive decrease in cerebral blood flow and oxygen consumption; may cause dizziness, loss of balance
- Changes in intellectual functioning depend on the individual
Subjective assessment of the neurological system
- Headache
- Head injury
- Dizziness/vertigo/ syncope
- Seizures
- Tremors
- Weakness
- Coordination/balance
- Numbness or tingling; Paraesthesia’s
- Difficulty swallowing; dysphagia
- Difficulty speaking; Dysarthria/dysphasia
- Significant past history
- Environmental and occupational hazards
- Sleep, nutrition, medications, substance abuse can throw off findings; ensure accurate picture
Sequence of complete neurological examination
1) Cranial nerves
2) Motor system
3) Sensory system
4) Reflexes
Testing cranial nerve i
Assess patency and sense of smell
Patency
- Want both nostrils open; not blocked by secretion – occlude one nostril and sniff
Sense of smell
- Use a familiar smell, i.e. mint, coffee, etc.
- Have them let you know when they smell it with eyes closed
Assessing cranial nerve ii
Assess visual acuity, visual fields, fundus
Visual acuity
- Snellen chart – optimistrist, letters on the wall
- Last line the patient can read with 2 or less errors
- 20/20 in healthy visual acuity
- Top number is distance standing from chart/bottom number is the number of letters the patient can read accurately
Visual field
- Peripheral vision
- Confrontation test
- Testing assuming the examiner has healthy peripheral vision
- Very gross assessment of peripheral vision
- Cover same eye and work with finger to see
Assessing cranial nerves iii, iv, and vi
Assess:
Palpebral fissures
- Symmetry, signs of infection, etc.
- Ptosis; drooping of one side of an eyelid, worried about nerve iii
Pupils
- PERRLA; Pupils Equal Round, Reactive to Light, and Accommodate
- Use pen light from side and then in front, pupil will constrict in response to light
- Inspect for roundness
- Accommodation means change in pupil size as someone changes from focusing on something close to something far away
Eye movements (EOM)
- Extra ocular movements
- Both eyes move together in a coordinated, smooth fashion
- Nystagmus – vibration of the eyes
- Test using a 6-points star
- Look straight ahead, with just eyes follow your finger movement
Assessing cranial nerve v
Sensory Function
- Assess light touch; use a wisp of cotton or gauze
3 spots on the face; chin, cheek, and forehead
Corneal reflex – touching the cotton towards the eye, expect the eyes to blink
- Assess corneal reflex only if necessary
Motor Function
- Assess temporal and masseter muscles, lower jaw movement
Assessing cranial nerve vii
Motor Function
- Assess mobility & symmetry with facial expressions
- Have them make faces, blow up cheeks and push air looking for symmetry
Sensory Function
- Assess sense of taste
- Not routinely tested (only when suspect injury)
Parasympathetic Functions
- Saliva and tear production
- Ask if mouth is dry and if they are producing tears or not
Assessing cranial nerve viii
- Assess hearing acuity; ability to hear
- Hear regular conversation; just while talking
- Whispered voice test; stand 2ft behind client, assess one ear at a time
- Occlude the tragus (one at a time)
- Whisper something abscure, then test the other side
Assessing cranial nerves ix and x
Motor Function
- Assess movement of pharynx
- Assess for gag reflex
- Only if observed no movement of the pharynx
Sensory Function
- Difficult to assess posterior
one third of tongue for taste
Assessing cranial nerve xi
- Trapeus and sternomastoid muscles
- Assess against resistance of examinor
- Equal resistance on both side
Assessing cranial nerce xii
- Assess movement of the tongue
- Assess movement of the tongue and person’s ability to articulate “light, tight, dynamite”
- Assessing strength of voice, enunciation
Motor system assessment: muscles
- Gross screening
- GO head to toe
- Size; equal on both sides
- Strength; equal on both sides
- Symmetry
- Tone; engage the client in passive ROM
- Involuntary movements; tremors, twitches, etc.
Motor system assessment: cerebellar function
Balance test
- Gait; smooth, steady, coordinated walking
- Ataxia; uncoordinated, unsteady gait
- Tandem walking; walking on line, heal to toe – any issue of coordination is increased when we decrease base of support
- Romberg test; feet together, arms at side, ask them to close their eyes (20 secs, positive test is if they completely lose balance
Coordination and skilled movements
- Rapid alternating movements; take finger and touch it to thumb, perform smoothly; OR hand son thighs alternate back and forth smoothly
- Finger to finger test; able to mostly do it; your finger, touch their nose then touch tour finger while you move your finger around
- Finger to nose test; eyes close, touching their nose with alternating finger
- Heel to shin test; lying or sitting on bed, have opposite heel touching shin, and slide down; should do smoothly on both sides
Sensory system assessment: spinothalamic tract
- Pain; break tongue blade and have them assess with eyes closed to feel sharp or dull sensation on skin
- Temperature; done if abnormal pain sensation test
- Light touch; points on periphery with light touch to assess
Sensory system assessment: posterior column tract
- Vibration; tuning fork
- Position; close eyes and move limbs in different positions
- Fine touch;
- Stereognosis – eyes closed put something familiar in hand, should be able to detect what it is
- Graphesthesia; use finger to write in hand letter or number
- 2 point discrimination; take paper clip and unfold it (2 pointy ends) and can alter the distance; fingertips can detect that it’s two distinct pints but not in gross areas such as back
Deep tendon reflex testing
- Test the reflex arc at a specific spinal level
- Biceps, Triceps, Brachioradialis, Quadriceps (patellar, knee jerk), Achilles
- Grade the response on a 4 point scale
- To elicit a good response; limb needs to be slightly bent, patient completely relaxed, if they know you will strike them they may tense (good to distract them)
- Examinor needs to be relaxed holding the hammer, relaxed wrist, strike in a quick gentle way
Grading a deep tendon reflex
\+4 - Very brisk, hyperactive with clonus (rhythmic jerking of muscles after reflex is elicited) \+3 - Brisker than average \+2 - Average, normal \+1 - Diminished, low normal 0 - No response
Superficial reflex testing
- Sensory receptors in the skin rather than muscles
- Plantar reflex; bottom of foot with back of hammer, draw and upside down ‘J’
- Expect tickle and toes turn over
- Unexpected finding is a full Babskini fan out of toes (only seen in infants)
