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202 Cards in this Set
- Front
- Back
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What is the most important tool in the neurologic dx?
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The history and physical.
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What should always be your first goal as you approach a pt w/ a neurological problem?
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Making the anatomical dx, then find the etiologic dx.
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What is the etiologic dx?
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It specifies the cause of a lesion and is mainly obtained from information provided by the neurologic history.
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What generally causes lesions of sudden onset
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Typically from the cerebrovasculature such as a stroke.
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What generally causes slowly progressive lesions?
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More likely due to expanding mass lesions such as tumors or abscesses.
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What generally causes lesions w/ exacerbating and remitting courses?
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Demyelination such as w/ multiple sclerosis.
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What generally causes relentlessly progressive lesions involving all areas of the nervous system?
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Degenerative disorders of the nervous system like Alzheimer's disease.
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What is critical and requires great attention to the details when taking the neurologic history?
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An accurate, chronological description of the pts presenting illness. ESPECIALLY for acute spells (such as seizures), where you must obtain a minute by minute account of the event.
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What does assessing cognition imply?
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evaluating higher cortical functions.
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How can you assess mental status in a pt who is unable to communicate (pt has a language problem, or is intubated)?
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Ask the pt to follow commands like: (1) close your eyes (2) close your eyes and point to the ceiling (3) touch both shoulders two times w/ two fingers
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What kind of damage will produce abnormalities of cognition?
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Damage to large areas of the cerebral hemispheres.
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What structures are required for consciousness?
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(1) brainstem reticular activating system - which "wakes up" the cerebral cortex
(2) one cerebral hemisphere. *so a pt will be rendered unconscious if injury has occurred to both cerebral hemispheres or to the brain stem reticular activating system. |
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What categories do pts fit into if they perform poorly on the mental status exam?
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1. dementia
2. encephalopathy |
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What is dementia?
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A slowly progressive intellectual decline, eventually deterioration in many areas occurs: memory, calculation, interersonal communication, motor function, gait and judgement.
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What is encephalopathy?
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An acute or subacute change in the pts mental state. Delirium is another common name.
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What causes encephalopathy?
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Many causes but the most often one is due to medications taken inappropriately, infection or some other reversible process.
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What is the onset, course, pts attention and reversibility of encephalopathy vs dementia?
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*encephalopathy is acute/subacte, it fluctuates in course, it prominently impairs attention and is often reversible.
*dementia: is chronic (slow), the course is chronic progressive, the attention is less impaired and is only rarely reversible. |
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What disorders should be ruled out in the language and speech exam?
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Dysarthria and aphasia.
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What is dysarthria?
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A speech disorder (slurred speech) that can be caused by an infinitely long list of neuro and non-neuro abnormalities.
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What other disorder do pts w/ encephalopathy frequently have that is picked up in the language and speech exam?
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Dysarthria slurred speech.
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What will an abnormality of the vocal apparatus (tongue/facial weakness, etc) cause?
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Results in dysarthria (slurred speech)
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What is aphasia?
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A language abnormality that is an acquired disorder in the production of language due to a lesion involving the dominant cerebral hemisphere.
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When is a great time to evaluate a patients language and speech during a neurologic exam?
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While the pt is describe his/her complaint.
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What is most often the dominant hemisphere in right-handed people? left-handed people?
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left hemisphere is most often the dominant hemisphere in 95% of right handers and 70% of left handers.
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How can you test to see if the pt has an aphasia?
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By asking the patient to repeat a sentence like "now that he is gone, we must go away". As well as observing the pt name objects, read and write.
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What are the three main types of aphasia?
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1. expressive aphasia
2. receptive aphasia 3. conduction aphasia |
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What is expressive aphasia?
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"motor/broca's aphasia"
Usually seen involving the posterior inferior frontal lobe (broca's area); expressive aphasia is marked by significant difficulty producing language but w/ relatively little understanding. |
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What additional symptoms are present in pts w/ expressive aphasia?
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Right hemiparesis due to involvement of the adjacent motor cortex.
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What is a receptive aphasia (sensory or Wernicke's aphasia)?
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Seen w/ a lesion involving the supramarginal and angular gyri in the parietal lobe as well as the posterior superior temporal lobe (wernicke's area).
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What characterizes receptive aphasia?
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fluent speech but w/ markedly impaired understanding, typically the pt makes numerous errors in pronunciation and naming called paraphasic errors.
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What is global aphasia?
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A large left hemisphere lesion that involved both Wernicke's and Broca's are results in global aphasia where the pt cannot understand or speak.
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What is a conduction aphasia?
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Results from a lesion of the arcuate fasciculus (connects wernicke's and broca's areas); since both of these areas are intact, pts are fluent and can understand, however when asked to repeat a sentence the pt will have difficulty.
Very rare! |
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How can you test the olfactory nerve? (CNI)
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By occluding one nostril and presenting a non-volatile stimulus (coffee, spices, etc.) to the other nostril. Then repeat on the other side.
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Why should you never use irritative substance during the olfactory exam? (i.e. ammonia or smelling salts)
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B/c these are a pain reflex stimulator not a smell reflex stimulator and will stimulate the trigeminal nerve rather than olfactory fibers.
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When should you evaluate a pts sense of smell?
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After head trauma, b/c the olfactory nerve may be sheared off as it penetrates the cribriform plate.
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What cancers can affect a pts sense of smell?
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Meningiomas (benign tumors originating form the meninges) b/c they invade the cribriform plate.
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What is the most common cause for a loss of smell?
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non-neurologic and due to inflammation of the nasal mucosa during an upper respiratory infection.
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What are the three components of the optic nerve that are typically evaluated?
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1. visual acuity
2. visual fields 3. ophthalmoscopic exam |
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How is visual acuity checked? what does visual acuity measure?
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Each eye is checked individually and visual acuity is checked by means of a snellen chart or near card.
Visual acuity measures only macular vision, which is the central 5 deg. of the visual field. |
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What dzes affect visual acuity? why?
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ONLY lesions anterior to the optic chiasm; b/c visual information from one eye crosses to both hemispheres at the optic chiasm. SO only a bilateral lesion posterior to the optic chiasm could affect visual acuity.
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What symptoms would a young patient with demyelination of the optic nerve (optic neuritis) present with? what bigger dz is this usually associated with?
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Subacute loss of visual acuity in one. Usually associated w/ multiple sclerosis.
MS causes various areas of the CNS to lose myelin (most often the optic nerve) |
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How are the visual fields evaluated?
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By the confrontation method where the examiner stands directly in front of the pt (2-3 feet away). The pt is asked to cover one eye. With the pt fixating on the examiner's nose, finger counting is then done in all four quadrants (the finger-wiggle technique is sub-optimal) and each eye is checked individually.
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What will a pt w/ a lesion to one optic nerve present with?
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monocular blindness
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What would a pt with a lesion/tumor that wraps around the optic chiasm present with?
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loss of the temporal retina in both eyes or a binasal hemianopia.
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What would a pt with a lesion or pituitary tumor present with on optic exam?
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They would have a loss of vision in the nasal retina or a bitemporal hemianopia or "tunnel vision".
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Where does the optic tract synapse after the optic chiasm?
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The lateral geniculate body.
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What would a lesion to the optic tract on the left side cause? right side?
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left: it would cause visual loss on the right side of both eyes.
right: it would cause vision loss on the left side of both eyes. |
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What would a pt with a lesion to Meyer's loop present with?
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Contralateral superior contranopsia or "pie-in-the-sky", so on the left it would cause the upper right field of vision to be lost.
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What would a pt with a lesion to the visual radiation to the cuneus present with?
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Contralateral homonymous inferior contranopsia or "pizza-on-the-ground". So if the lesion is on the left the bottom right quarter of the visual field is lost.
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What would a pt with a stroke to the PCA present with on optic exam?
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The macular fibers have a dual blood supply from the MCA so the center of the visual field is preserved but other than that it is the same as a lesion to the optic tract where the opposite-lateral field is lost.
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What cranial nerves are tested by the pupillary light reflex?
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CN III and CN II
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What neurological dx'es can be made by examining the retina?
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Increased intracranial pressure, demyelination of the optic nerve.
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How can you dx inc. intracranial pressure on ophthalmologic exam?
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By looking for optic disc swelling or papilledema which occurs w/ mass lesion of the brain.
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How can you dx. demyelination of the optic nerve on eye exam?
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By the pallor of the optic disc; which occurs in multiple sclerosis.
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What's the dx?
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Optic disc pallor which occurs in multiple sclerosis.
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What's the dx?
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Papilledema
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What are the parts to the examination of the oculomotor III, trochlear IV and abducens VI exam?
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1. pupillary light response
2. ocular movements 3. ptosis evaluation |
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What nerve carries PNS fibers that cause constriction during the pupillary light response?
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CNIII or oculomotor.
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What nerves are assessed by the pupillary light reflex?
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CNII and CNIII
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What is the path of the pupillary light reflex?
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light => optic chiasm => both optic tracts to the pretectal nucleus in midbrain => PNS of both CNIIIs (edinger-westphal nucleus) is stimulated => the contralateral nucleus via the posterior commissure.
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What is the sympathetic pathway for pupillary dilation?
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1st order neuron: hypothalamus => brain stem => T1-T2 intermediolateral cell column.
2nd order neuron: T1-T2 intermediolateral cell column => white rami of nerve roots T1-T2 (over apex of lung) to the => superior cervical chain => superior cervical ganglia. 3rd order neuron: Superior cervical ganglia => on the surface of carotid artery => nasociliary br. of CNV => pupil dilator. (the 3rd order neuron also supplies Muller's muscle (eyelid elevation) |
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What would a lesion in either the 1st or second order neurons of the sympathetic pupillary dilation pathway cause?
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Horner's syndrome which is characterized by mild ipsilateral pupillary constriction (miosis) and mild ipsilateral ptosis (drooping of the eyelid).
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If there is a lesion in the SNS pupillary dilation pathway proximal to the superior cervical ganglion what will the pt present with?
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Horner's syndrome as well as decreased ipsilateral sweating (anhydrosis) which may be present due to interruption of sympathetic fibers which supply the blood vessels and sweat glands of the face.
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What could cause a lesion to the 1st order neurons of the SNS pupillary light dilation pathway?
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brain stem stroke or hemorrhage, cervical spinal cord trauma or demyelination.
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What could cause a 2nd order lesion to the SNS pupillary light dilation pathway?
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Pancoast tumor (apical lung tumor).
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What could cause a 3rd order lesion to the SNS pupillary light dilation pathway?
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Carotid artery dissection and some migraine headache variants.
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What does a lesion of CN III (3rd nerve palsy present with?
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Difficulty moving the eye, a marked ptosis and dilation of the pupil (mydriasis)
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How are ocular movements assessed?
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By having the pt follow the examiner's fingers in space.
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What eye muscles are controlled by CNIII?
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Medial, inferior, superior rectus and inferior oblique
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What eye muscles are controlled by CN IV?
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Superior oblique
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What eye muscles are controlled by CN VI?
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Lateral rectus
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What direction will a pt's eye be pointed if they have 3rd nerve palsy? what associated symptoms will they have?
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The eye will be deviated down and out (due to the unopposed pull of the lateral rectus and superior oblique.
They will also have ptosis and mydriasis (dilation of pupil). |
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What's the dx?
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left eye deviated inferolaterally (intact CN IV and VI); is dilated and there is complete ptosis. The intorsion is due to the action of the superior oblique.
dx: 3rd nerve palsy. |
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What symptoms will a pt w/ a lesion to CN VI present with?
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Inward deviation of the eye (due to the unopposed pull of the medial rectus)
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What's the dx? the pt is trying to look at your nose
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CNVI lesion
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What does a lesion to CN IV cause?
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Vertical diplopia
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A pt comes into your clinic complaining that when they walk down stairs or try to read a book results in diplopia. what's the dx?
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A lesion to CN IV; tilting the head to the opposite shoulder minimized the diplopia.
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What is the Vestibulo-Ocular reflex?
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This fixates the image on the retina w/ respect to head motion. Head motion is a form of angular acceleration that stimulates the semicircular canals in the inner ear.
*Basically it acts like a gyroscope for the eyes, when it is not functioning properly it causes the pt to feel like their in an episode of cops where the camera bounces and shakes with every footstep. |
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What does a normal vestibular ocular reflex mean? what pts is it used in?
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Suggests that the brainstem is probably intact and that the cause for the coma does not lie in the brain stem. So this reflex is used to assess whether a coma pt has an intact brainstem.
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What is "visual pursuit"?
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A reflex that fixates the image on the retina w/ respect to image motion.
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What region of the brain senses image motion?
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Image motion is sensed by the occipital cortex which then relays this information in both a crossed and uncrossed manner to the lateral gaze center in the pons (the paramedian pontine reticular formation PPRF) and then via the MLF to CN III, IV and VI
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What is visual saccade?
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The stimulus for this ocular movement originates in the frontal eye fields (saccadic gaze center of middle lobe of frontal cortex). This information then crosses to the lateral gaze center (PPRF) in the pons, and then is related via the MLF to CN III, IV and VI in an analogous fashion as for the other two eye movements.
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If a pt has a cortical lesion that affects the MCA, what will be the pts presenting symptoms in their eyes?
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The eyes will look away from the hemiplagia so if the stroke was to the left MCA the right arms/legs would lose control and the eyes would look to the left. (left gaze preference)
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What would be the presenting symptoms of a pt w/ a right pontine stroke?
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The pt would suffer damage to their right pons, SO they would have left hemiplagia AND left gaze palsy, or the eyes would look AT the hemorrhage.
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If a pt suffered a lesion to the left medial longitudinal fasciculus (an INO - internuclear opthalmoplegia) what would the pt present with?
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They would suffer weakness of the ipsilateral medial rectus. So they would be able to look to the left normally, but when they try to look right their would be nystagmus in the normal right eye (unaffected eye).
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What dx should you make if you find a MLF lesion in a young pt?
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Virtually diagnostic of MS
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How is nystagmus named?
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By the direction of the fast component.
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What are the physiologic causes of nystagmus?
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1. end-position
2. optokinetic 3. kinetic |
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What are the pathologic causes of nystagmus?
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1. vestibular lesions
2. cerebellar lesions 3. brain stem lesions 4. drugs - ESPECIALLY phenytoin, a chemotherapeutic 5. congenital |
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Where does the trochlear nerve emerge?
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From the dorsal surface of the Pons under the colliculi
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What's the dx?
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3rd nerve palsy
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What's the dx?
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Horner's syndrome
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What's the dx? The pt is trying to look directly at you.
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CN VI lesion in left eye, note the inward deviation of the left eye due to the unopposed pull of the medial rectus.
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What are the presenting symptoms of a cortical lesion involving the saccadic gaze center?
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The lesion will result in a lesion to the motor control to the body on the opposite side as the lesion. Also gaze preference where the eyes look away from the hemiplegia. SO a left sided lesion will cause loss of motor control on the right side of the body and the eyes will look to the left.
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What ocular symptoms would a pt w/ a right pontine lesion present w/?
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The pt's eyes would look towards their hemiplegia, so they would have a left side hemiplagia and a left gaze palsy
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What ocular symptoms would a pt with a medial longitudinal fasciculus lesion present with?
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The lesion would result in an internuclear ophthalmoplegia (INO). Pts w/ INO have weakness in their ipsilateral medial rectus, w/ an associated nystagmus in the normal eye.
*In a young pt this is diagnostic of MS. |
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What is nystagmus?
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A rhythmic, oscillatory involuntary movement of one or both eyes that may occur spontaneously or be evoked by a specific duration of gaze.
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How should sensory examination of CNV be carried out?
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Each division should be tested separately for touch, temperature and pinprick sensation.
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How is the corneal reflex tested? what nerves are being tested?
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By touching the cornea w/ a wisp of cotton while observing for any asymmetry of the blink response.
The afferent limb is carried by the ophthalmic br. of CNV which is sensory to the cornea. The efferent limb uses CNVII. |
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What is a normal corneal reflex?
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Both eyes blink symmetrically when the eye is touched by cotton.
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What is the corneal reflex pathway?
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The impulse from the spinal trigeminal nucleus reaches the facial nucleus via interneurons in the reticular formation.
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How are the motor branches of CNV tested? what muscles are tested?
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Temporalis, masseter, lateral/medial pterygoid.
They are tested by testing jaw closure, jaw opening and side-to-side jaw movement. |
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How are the motor branches of CNVII tested?
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By asking the pt to wrinkle the forehead, close the eyes tightly, smile and frown.
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What would the pt pw if they have a lower motor neuron lesion of the facial nerve (Bell's Palsy)? of the facial nucleus in the brain stem?
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The pt would have weakness of both the forehead and face.
*So they couldn't wrinkle the forehead, smile or close the eye tightly. |
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What would the pt pw if they had an upper motor neuron lesion involving the cerebral cortex or the corticobulbar pathway that connects the cortex w/ the facial nerve nucleus? why?
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Weakness of the lower half of the face only. B/c the forehead receives bilateral cortical innervation.
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How is taste assessed?
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By applying different tastes to the anterior 2/3rds of the tongue.
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What symptoms would a pt pw if they had a unilateral lesion in the genu of the internal capsule?
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This is an UMN lesion of the corticobulbar tract that would cause the pt to have one-sided lower facial weakness w/ sparing of the forehead.
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What aberrant regenerations can occur in Bell's palsy?
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Nerve fibers from the orbicularis oris muscle may regrow to supply the orbicularis oculi so when the pt tries to purse their lips the eye squints.
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How can the cochlear division of CNVIII be tested?
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By assessing the pt's ability to hear a ticking watch or by rubbing two fingers held a certain distance from the ear.
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What are the two forms of "hearing loss"?
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Conductive hearling loss and sensori-neural hearing loss.
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What is conductive hearing loss?
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A lesion to the structures in the outer or middle ear which convert air conduction into bone conduction.
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What is sensori-neural hearing loss?
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A lesion of the inner ear or of CNVIII
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What is the Weber test? what does it test for?
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A vibrating tuning fork is placed at the vertex of the skull and the pt is asked to localize the sound. Normally the sound should be heard equally in both ears w/ lateralization being abnormal.
If the sound is localized to the "bad ear" it is conductive hearing loss. If the sound is localized to the good ear" it is a sensori-neural hearing loss. |
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What is the Rinne test?
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The base of a vibrating tuning fork is placed against the mastoid process until the sound is no longer heard. The prongs are moved adjacent to the external ear.
If the sound is no longer heard in this second position, a conductive hearing loss is suspected. If the sound is not or is diminished w/ a normal relationship than it is sensori-neural hearing loss. |
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When should the vestibular division of CNVIII be evaluated?
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In pts complaining of dizziness or vertigo.
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How can the vestibulo-Ocular Reflex (VOR) be tested?
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By having the pt read a Snellen chart while the head is rotated back and forth. Deterioration of MORE than one line is an abnormality. You can also check for nystagmus at rest.
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What is Labyrinthine stimulation? what does it *****?
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Uses the Dix-Hallpike positioning maneuver to test the vestibular division of CN8. The pt is quickly moved from a sitting position to a supine one w/ the head below 45deg. and turned to one side. (repeat for other side) if the pt reports vertigo during the maneuver or if nystagmus develops vestibular dysfunction may be present.
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What is caloric testing?
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An alternative way to stimulate the labyrinth. Hot/cold water is introduced into the external auditory meatus and the pt is observed for development of nystagmus or eye movements.
*BEST in comatose pts to test the brain stem. |
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How is the vagus nerve tested?
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By asking the pt to phonate and observing for a symmetrical rise in the palate and uvula.
*"open your mouth and say ahhh" |
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What is the gag reflex? what does it test?
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The examiner touches the posterior pharyngeal wall w/ a tongue depressor and observes for a symmetric rise in the soft palate and uvula.
The afferent limb is carried by CN9 and the efferent is CN10. |
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How is CN11 tested?
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By asking the pt to rotate the head against resistance (right SCM allows the pt to turn the head left). Trapezius is assessed by asking the pt to shrug.
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How is CN12 tested?
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By asking the pt to protrude the tongue or push into the cheek against resistance.
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What would a lesion to the hypoglossal nerve cause?
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It would cause the tongue to deviate towards the side of the injured nerve.
*the pt would lick their wound! |
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What CNXII Sys would a pt pw if they had a lesion to the genu of the internal capsule?
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can OCCASIONALLY result in deviation of the tongue away from the lesion, but more often the loss is bilateral and the tongue does not deviate.
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What cranial nerves carry the afferent and efferent limbs of the pupillary reflex?
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afferent: II
efferent: V |
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What cranial nerves carry the afferent and efferent limbs of the Jaw jerk reflex?
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afferent: V
efferent: V |
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What cranial nerves carry the afferent and efferent limbs of the corneal reflex?
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afferent: V
efferent: VII |
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What cranial nerves carry the afferent and efferent limbs of the Gag reflex?
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afferent: IX
efferent: X |
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What cranial nerves carry the afferent and efferent limbs of the vestibuloocular reflex?
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afferent: VIII
efferent: III, IV, VI (via MLF) |
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What are the grades for muscle strength on a 5-point scale?
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What are the most important functional tests to assess motor strength?
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Finger tapping and pronator drift.
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How is pronator drift tested?
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By having the pt hold both hands outstretched w/ palms up and eyes closed. The examiner then watches for subtle pronation of the arm which indicates a UMN injury.
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What is the finger tapping test useful for assessing?
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Assesses the basal ganglia and the cerebellum.
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What is the most important UMN pathway?
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The corticospinal tract.
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What is the corticospinal tract pathway?
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Begins in the frontal lobe, crosses in the lower medulla and eventually synapses in the anterior horn cells in the contralateral spinal chord.
*So the right brain controls motor functions on the left side of the body. OR a right-sided lesion will cause left-sided weakness. |
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What muscle weakness will a pt pw if they have a lesion (say a herniated disc) to the right spinal chord?
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The right side of the body will be weak below the lesion (b/c the corticospinal tract has already crossed.
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What are the 1st order neurons in the corticospinal tract? 2nd order? 3rd order?
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What is muscle tone?
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The resistance of a muscle to passive stretching.
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What change in muscle tone will be observed in a UMN lesion?
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What change in muscle tone would be observed in a basal ganglia lesion?
*like Parkinson's dz i.e. |
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What change in muscle tone would be observed in a bihemispheric lesion?
*like a neurodegenerative dz like Alzheimer's i.e. |
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What is muscle atrophy? what are the main causes/kinds of atrophy?
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Loss of muscle bulk.
1. Denervation atrophy - which is a profound form of muscle atrophy seen w/ a LMN lesion. 2. Disuse atrophy - A mild form of muscle atrophy seen in many settings such as a UMN lesion or having a leg in a cast. |
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What are fasciculations?
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Worm-like contractions of muscle due to random discharge of an entire motor unit. Usually benign (eye twitches) but can also be seen in dzes of the LMNs; ESPECIALLY those involving anterior horn cells.
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What dzes affect anterior horn cells?
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1. Amyotrophic lateral sclerosis
2. polio |
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What is the basic cause of movement disorders?
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Pathology in the basal ganglia.
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What dz is characterized by a rest tremor? where is the pathology located?
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Parkinson's dz which is caused by substantia nigra degeneration.
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What dz is characterized by chorea? where is the pathology located?
*chorea is brief, irregular writhing movements |
Huntington's dz which is caused by striatum degeneration.
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What specific kind of nerve fibers carry pain?
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Small unmyelinated fibers.
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What is the spinothalamic tract?
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Used by pain fibers from the left left ascend to the brain in the right spinal chord. These fibers then synapse int eh ventral posterior lateral nucleus of thalamus. They terminate in the post-central thalamus.
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What is the centrum semiovale?
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The area of white matter right underneath the gray matter of the cerebrum.
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What is protopathic sensation?
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Pain and temperature
*remember a new safety pin should be used and discarded after the single examination. |
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How is temperature assessed?
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Using a cool tuning fork.
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What is the spinothalamic tract?
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1st order: Pain is carried by small unmyelinated fibers to the spinal chord. Upon reaching the SC these fibers rise ~2 levels in Lissaeuer's tract then cross through a ventral white commissure.
2nd order: They rise up through the SC on the opposite side they started from in the spinothalamic tract in the lateral medulla. Then they synapse in the VPL (ventral posterior lateral) nucleus of the thalamus. 3rd order: They leave the thalamus and terminate in the post-central gyrus. |
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What is epicritic sensation?
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Vibration and Proprioception (the ability to sense the position and orientation of limbs and body parts)
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What kind of nerve fibers carries epicritic sensation?
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Large, myelinated fibers
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How is proprioception evaluated?
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By assessing position sense at interphalangeal joints w/ slight degrees of motion, the dr grasps the pts joint laterally so as not to provide pressure clues.
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What is the epicritic pathway?
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1st order: DRG travel upwards through the ipsilateral spinal chord in either the fasciculus cuneatus or gracilis untilt hey reach the nucleus cuneatus/gracilis at the border of the medulla and spinal chord.
2nd order: THEN the neurons cross over to the contralateral side of the CNS via the internal arcuate fiber and ascend to the ventral posterior lateral nucleus in the thalamus and synapse. 3rd order: the VPL neurons then synapse in the post-central gyrus. |
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What is the Fasciculus Gracilis?
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Epicritic sensation below the T7 vertebral level (basically from the legs) ascends in the dorsal columns of the spinal chord in the fasciculus gracilis to synapse in the nucleus gracilis.
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What is the fasciculus cuneatus?
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Epicritic sensation from T7 upwards (basically from the arms) ascends in the dorsal columns of the spinal chord int he fasciculus cuneatus to synapse in the nucleus cuneatus.
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What makes up the dorsal columns of the spinal chord?
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The fasciculus cuneatus and the fasciculus gracilis.
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What is the Romberg test?
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A way of assessing posterior column function, this test is performed by asking the pt to stand w/ his/her feet together and then close their eyes. The pt is then observed to see if balance can be maintained. If they fall the test is positive.
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What systems are used in order to maintain balance?
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1. proprioception
2. vestibular apparatus 3. vision |
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What does it mean if a pt is able to maintain balance w/ their eyes closed? if they cannot maintain balance?
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If they CAN maintain balance it implies integrity of both the vestibular apparatus and proprioception.
If they CANNOT maintain balance one of these systems is dysfunctioning. |
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When is it NOT a good idea to perform the Romberg test?
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In pts that are not able to stand well w/ their feet together and their eyes open.
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What are peripheral neuropathies?
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Dz of the peripheral nerves.
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What nerve fibers do most peripheral neuropathies affect?
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Pain and temperature fibers, though some neuropathies preferentially involve the large fibers that carry vibratory and proprioceptive information.
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What movement symptoms are caused by cerebellar dz?
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Poor coordination of voluntary movement (ataxia) but NOT weakness.
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What are the aspects of coordination testing?
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truncal stability and limb coordination.
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How is truncal stability assessed?
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By observing the pts balance when sitting, standing or walking.
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What does truncal ataxia dx? what causes this to occur?
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A midline cerebellar (VERMIS) lesion, which is caused by chronic alcohol abuse.
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How is limb coordination assessed?
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Upper limb: The pt is asked to touch his/her nose w/ the index finger, then the examiner's finger and then back to his/her nose. (finger-to-nose test)
Lower limb: The pt is asked to slide one heel down the opposite shin. (heel-to-shin test) |
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What does an ataxia of limb movement dx?
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A lesion in the cerebellar hemisphere.
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What side of the cerebellum controls what side of the body?
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Unlike the cerebral cortex (the brain) in which one hemisphere controls the opposite side of the body, one cerebellar hemisphere controls the same side of the body (the right cerebellum coordinates the right arm and leg).
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What would ataxia of the right arm/leg dx?
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lesion of the right cerebellum
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What are muscle stretch reflexes (deep tendon reflexes)?
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Muscle stretch reflexes are monosynaptic spinal chord reflexes that are elicited by striking the muscle tendon w/ a percussion hammer
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What is the general monosynaptic muscle stretch reflex pathway?
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Strike the muscle tendon w/ a hammer => stretches muscle spindle and sends afferent sensory info to the dorsal root/dorsal horn of SV => synapses on a corresponding anterior horn cell in the ventral horn of SC => efferent arm originates in the anterior horn cell, exits SC and synapses on same muscle.
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What nerve roots are assessed using the achilles reflex?
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S1-2
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What nerves are assessed by the Patellar reflex?
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L2-4
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What nerve roots are assessed by the Brachioradialis?
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C5-6
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What nerve fibers are assessed by the Biceps reflex?
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C5-6
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What nerve fibers are assessed by the Triceps reflex?
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C6-8
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What are the grades for reflexes? which ones are considered sometimes pathologic? always pathologic?
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Grade 0 is sometimes pathologic w/ LMNs
Grade 4 is ALWAYS pathologic w/ UMNs |
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What is clonus?
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A rhythmic series of involuntary muscle contractions induced by the sudden passive stretching of a muscle. Most easily elicited at the ankle.
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What does Clonus indicate?
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A UMN lesion.
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What is the Babinski sign? how is it produced?
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Performed by striking the lateral aspect of the sole of the foot w/ a painful stimulus, starting at the heel and then crossing the ball of the foot towards the great toe. NORMALLY the toe goes down or does not move.
A positive Babinski response consists of dorsiflexion of the great toe. |
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What does a positive Babinski dx?
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A UMN lesion.
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What are frontal release signs?
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Reflexes that are present in infancy and then lost w/ maturation of the CNS and then regained w/ advanced age or w/ diffuse cortical or bihemispheric dysfunction. (Alzheimer's dz or bihemispheric strokes).
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What are the frontal release signs?
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1. Snout reflex
2. Palmomental reflex 3. Grasp reflex 4. Glabellar sign |
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What is snout reflex?
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Elicited by repeatedly tapping the upper lip and observing for puckering of the lips. One way of eliciting this reflex is to place a tongue blade lightly over the upper lip and then tap the tongue blade w/ a percussion hammer.
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What is the Palmomental reflex?
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Elicited by scratching the thenar eminence of the palm w/ a blunt object and observing for an ipsilateral contraction of the mentalis muscle on the chin.
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What is the Grasp reflex?
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Obtained by having the examiner stroke the skin of the pts palm w/ his/her fingers and observing for a resultant grasping of those fingers by the pt.
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What is a Glabellar sign?
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Elicited by tapping the forehead repeatedly b/e the eyebrows over the glabella and observing for persistent blinking. It is important to note that a normal individual will blink once or twice ONLY w/ this maneuver.
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How is Gait assessed?
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By watching the pt walk normally. Making the gait more difficult by having the pt walk on his/her toes and heels, including tandem gait (heel-to-toe walking) is also performed.
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What lesion causes hemiplegic walking?
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A UMN lesion (stroke)
*so a stroke on the right will cause this on the left |
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What's the dx?
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A hemiplegic lesion caused by a UMN lesion typically a stroke.
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What is a steppage gait? what causes it?
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Where the pt cannot dorsiflex their foot so they step really high to not trip over their foot (far left)
It is caused by a peroneal nerve palsy. |
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What causes a sensory ataxic gait? What is a sensory ataxic gait?
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A lesion to the posterior columns of the SC. It is a wide-based lunging kind of walk where the pt has a hard time maintaining stability.
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What causes a cerebellar ataxic gait? what is a cerebellar ataxic gait?
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A lesion to the cerebellum and is a wide based lunging kind of gait.
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What causes a spastic (scissored) gait? what is this gait?
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Caused by a bilateral UMN (cerebral palsy) and is a gait where the pt is hunched, bent at the knees and swings (scissors) the lower extremity around w/ the upper extremity held at ninety-degrees T-rex style.
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What causes a festinating (shuffled) gait? what is a festinating (shuffled) gait?
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The pt is hunched over and shuffles forward and moves foward very slowly.
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Name the gaits:
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Steppage, scissored, parkinsonian, hemiparetic and hysterical
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How can you differentiate b/e a UMN lesion and a LMN lesion based on reflexes, Babinski, tone, weakness, atrophy and fasciculations/fibrillations?
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