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Neurological Examination Physical Diagnosis Learning Objectives • Select appropriate questions to elicit from the patient with a neurological complaint during a patient interview • Differentiate “normal” from “abnormal” findings on neurological examination • Identify common causes of various cranial nerve palsies • Differentiate conductive hearing loss from sensorineural hearing loss • Determine location of neurological lesion • Differentiate amongst the various movement disorders Learning Objectives • Differentiate atrophy, hypertrophy, and pseudohypertrophy. • Differentiate between spasticity, rigidity, and flaccidity, and identify common causes of each. • Differentiate upper motor neuron lesions from lower motor neuron lesions. • Differentiate CNS disorders from PNS disorders, and identify location of the lesion & common causes. • Compare and contrast the five clinical levels of consciousness. • Given a case study perform the appropriate focused history and physical examination and formulate a differential diagnosis Purpose • Determine if there is a neurological deficit – Sensory – Motor – Behavioral – Coordinative • Localize the site of the problem • Determine the etiology of the problem Terminology • Paresis – slight or incomplete paralysis • Paralysis (plegia) – loss or impairment of motor function • Hemiparesis • Hemiplegia • Paraplegia • Quadriplegia Terminology • Atrophy – a decrease in size • Hypertrophy – enlargement of an organ or part due to an increase in size of its constituent cells • Pseudohypertrophy – increase in size without true hypertrophy • Spasticity – hypertonicity with increased DTRs • Rigidity – stiffness or inflexibility • Flaccidity – loss of tone with diminished DTRs Focuses • Mental status • Cranial nerves • Motor function • Reflexes • Sensory status • Coordination and balance History • • • • • • • • • Chief complaint PQRST Headache? Vertigo? Visual disturbance? Tremors or dyskinesias? Weakness? Dysesthesias/Paresthesias? Loss of consciousness? Key components of H&P Complaint Hx P.E. Altered mental status Vertigo Associated seizure activity; recent trauma or infection; illicit drug use; exposure to toxic substances Mental status exam; pupillary reaction; corneal reflexes; gag reflexes; posturing/motor asymmetry; Babinski Differentiate between true vertigo and lightheadedness! Present at rest; affected by positional changes CN VIII function; Dix-Hallpike maneuver; nystagmus Headache Thorough hx; “worst headache ever?”; associated sx’s; neck pain/stiffness CN function; pupillary reaction; fundoscopic exam; palpate temporal artery; Marcus-Gunn Seizures Previous hx; frequency; motor activity; aura; LOC; post-ictal confusion; external etiology Search for focal deficits; signs of trauma; hyperreflexia Weakness Generalized or focal; loss of strength; pain; progressive or recurrent fatigue Asymmetry7; atrophy; sensory deficits; fasciculations; DTRs Mental Status • Alertness • Attention • Orientation – Person, Place, Time, & Situation • Cognitive function • Perception – Illusions = misinterpretations of real external stimuli – Hallucinations = subjective sensory perceptions in the absence of stimuli • Judgment • Memory – Short-term & long-term • Speech – – – – Rate & rhythm Spontaneity Fluency Simple vs. complex Levels of Consciousness • Alert and Oriented • Disoriented • Obtunded – Drowsy/somnolent – Clouded consciousness – Slow thought, movement, and speech • Stuporous – Marked reduction in mental and physical activity – Vigorous stimuli needed to provoke a response • Comatose – – – – Completely unconscious Cannot be aroused by painful stimuli Absence of voluntary movement +/- reflexes Glasgow Coma Scale Malingering (Nonorganic) • Hand drop • Blindness – EOM/I • Unilateral diplopia • Ammonia reaction (CN V vs. CN I) • Absence of pain or weakness in different positions The “Difficult” Patient • • • • Observation is key! Use ingenuity! Be patient! Agitated – May be threatening or violent • Unresponsive – Fail to participate • Unreliable – Inattentive, preoccupied, inconsistent information • Hysterical – Uncooperative Testing Cognitive Function • Information & vocabulary – Common • Calculating – Simple math – Word problems • Abstract thinking – Proverbs – Similarities/differences • Construction – Copy figures of increasing difficulty (i.e. circle, clock) Abnormalities of Thought Processes Circumstaniality Indirection and delay in reaching a point because of unnecessary detail. Loose Associations Person shifts from one unrelated subject to another. Flight of Ideas Almost continuous flow of accelerated speech with abrupt topic changes. Incoherence Incomprehensible because of illogic, lack of meaningful connections, abrupt topic changes, or disordered word use/grammar. Confabulation Fabrication of facts or events to fill in gaps in impaired memory. Perseveration Persistent repetition of words or ideas. Echolalia Repetition of the words or phrases of others. Neologisms Invented or distorted words. Blocking Sudden interruption in mid-sentence or before completion of an idea. Clanging Person chooses a word based on sound instead of meaning. Abnormalities of Thought Content Obsessions Recurrent, uncontrollable thoughts, images, or impulses that a persons considers unacceptable or strange Compulsions Repetitive acts that a person feels driven to perform to prevent or produce some unrealistic future state of affairs. Delusions False, fixed, personal beliefs that are not shared by other members of the person’s culture. Phobias Persistent, irrational fears; accompanied by a compelling desire to avoid the stimulus. Anxieties Apprehensions, fears, or tensions that may be free-floating or focused (i.e. phobia). Feelings of Unreality A sense that things in the environment are strange, unreal, or remote. Feelings of Depersonalization A sense that one’s self is different, changed, or unreal. Identity is lost. Delirium vs. Dementia • • Although confusion and/or disorientation are signs of both Delirium and Dementia, they are different Delirium is an acute confusional state – It is potentially reversible – Delirium usually occurs over a period of days to months • Dementia is slow and insidious – It progresses slowly over months to years – Dementia is not reversible Condition Onset Pattern Orientation Attention Memory Duration Acute Fluctuating Usually impaired Impaired/ Fluctuating Impaired Hours or days Dementia Insidious Progressive Normal or impaired ~Normal Impaired Months or years Psychosis Variable Variable ~Normal Normal or impaired Normal or impaired Variable Delirium Visual disturbance • • • • • • • Onset? Progression? TIA = brief, intermittent visual loss Migraine = “wavy” Retinal detachment = “drawn curtain” Acute glaucoma = “rainbows” or “halos” Digitalis toxicity = yellow hue Vertigo • A sense of spinning – Person – Environment • Suggests dysfunction of – Vestibular apparatus – Vestibular nerve • Differentiate from “lightheadedness” and “faintness” – Results from impairment of brain oxygenation Dix-Hallpike maneuver Testing for Aphasia Word Comprehension Comprehension of spoken language through recognition (“point to your nose”) or understanding (“Can dogs fly?”). Repetition Repeat items of increasing complexity. Note the fluency and accuracy of the responses. Naming Name a series of objects or colors. Gradually increase difficulty. Note the fluency and accuracy of the responses. Reading Comprehension Have the patient follow several simple written commands. Writing Ask the patient to make up and write a sentence. Localization • CNS vs. PNS – Brain/Brain stem – Spinal cord – Peripheral nerves • Difficult when evaluating: – Radicular pain – Dysesthesia/paresthesia – Tremors – Incoordination Localization • Cerebrum – Impaired intellect, memory, higher brain function • Brain stem – unconsciousness • LMN – paralysis with loss of DTRs – muscle atrophy with fasciculation • LMN + anesthesia – peripheral nerve or spinal root • UMN – – – – involves whole muscle groups increased or spastic muscle tone +/- paralysis with DTR accentuation Positive Babinski Organic Disease • • • • • • • Asymmetric pupillary light reflex Abnormal fundus Ocular divergence Nystagmus Muscular atrophy Fasciculations Multiple complex signs/symptoms explained by a single lesion Headache • 5th most common reason for OP visit • Symptom! (not a disease) • Most important diagnostic clue is a steady, bilateral, nonthrobbing pain that is worse in the a.m. – May awaken patient – Worse with VALSALVA Types of Headaches • Tension • Sinus • Migraine – Classic – Common – Complicated – Cluster • Post-traumatic • Post-LP Types of Headaches • • • • • • • • Temporal Arteritis ICP Subarachnoid hemorrhage Infection Ocular Trigeminal neuralgia (Tic doloureaux) TMJ syndrome Toxic Headache History • Location – – – – Unilateral ~ migraine Periorbital ~ glaucoma/uveitis Parietal/Occipital ~ tension Neck ~ meningitis or Subarachnoid hemorrhage • Quality – “Throbbing” ~ vascular – “Intermittent jabbing” ~ Trigeminal neuralgia – “Pressure” ~ sinus • Radiation? • Severity • Timing – Constant vs. intermittent – Worse in a.m. or p.m. • Worst headache ever????? Headache History • Associated Sx’s – – – – – • • • • Visual disturbance Vertigo N/V Dysesthesias Aura Past medical history Family history Current medication/drug use Suspect an extracranial etiology if pain is the only symptom Physical Examination • Appearance • Behavior/Mannerisms – Gait and Posture – Motor behavior – Facial expressions • • • • Mood vs. Affect MMSE Test Cranial Nerves II through XII Fundoscopic examination Physical Examination • Test motor nerve function – Grip/SAR (Grade 0-5) – Station and gait – ambulate, turn, toes, heels, heel-to-toe, knee bend – Romberg • Test sensory nerve function – Pain +/- Light touch – Two point discrimination (normally <5mm) – Proprioception/Stereognosis/Vibration • Test deep tendon reflexes (0-4+) • Test for meningeal irritation - Kernig’s & Brudzinski’s signs • Straight leg raise – Used to identify potential discogenic injury and nerve root injury • Test Coordination – Finger-to-nose – Rapid alternating movements of hands & feet Reflexes • • • • • • • • • Corneal Pharyngeal Biceps Triceps Brachioradialis Abdominal Patellar (knee jerk) Achilles (ankle jerk) Babinski – Positive suggests UMN lesion Cranial Nerves • • • • • • • • • • • • I II III IV V VI VII VIII IX X XI XII - Olfactory - Optic - Oculomotor - Trochlear - Trigeminal - Abducens - Facial - Vestibulocochlear (Acoustic) - Glossopharyngeal - Vagus - Accessory - Hypoglossal Cranial Nerve I • Responsible for sense of smell • Receptors located in the upper 1/3 of the nasal septum. • Test each nostril separately. • Identify familiar odors. • Avoid noxious substances • Unilateral lesion = ipsilateral anosmia Cranial Nerve II • Responsible for vision • Test visual acuity!!!! • Pupillary size – Swinging-flashlight test • Visual fields – Peripheral vision – Test by confrontation • Fundoscopic examination – Papilledema Cranial Nerves III, IV, VI • CN III involved in: – Pupillary reflex – Opening of the eyelids – Most extraocular movements • CN IV – provides downward/inward eye movement • CN VI – provides lateral eye movement Cranial Nerves III, IV, VI • Check pupillary reaction/reflex – Direct & consensual • Check eye movement through all six Cardinal fields – Unilateral complete paralysis is usually caused by increased ICP or an aneurysm – Neither eye can move to the contralateral side • Eyes “look toward the lesion” – Injury may occur secondary to: • • • • • Infection Orbital fracture Internal carotid aneurysm Mastoiditis Increased ICP • Look for nystagmus* Pupil Abnormalities • Adie’s (Tonic) pupil – sluggish response • Argyll Robertson pupil – irregular/unequal pupils – weak/absent reaction to light – exaggerated contraction to accommodation • Marcus-Gunn pupil – results from reduced afferent input in the affected eye** – pupil fails to constrict fully – rapidly stimulate each eye in succession and observe the direct and consensual light response in each • stimulation of the normal eye produces full constriction in both pupils. • immediate subsequent stimulus of the affected eye produces an apparent dilation in both pupils since the stimulus carried through that optic nerve is weaker Pupil Abnormalities • Asymmetry of pupil size of >1mm suggests CN III compression • Bilateral dilation suggests anoxia or drug affect • Unilateral constriction is seen with sympathetic dysfunction (Horner syndrome) or carotid artery dissection • Bilateral constriction is seen with: – Pontine hemorrhage – Drugs (opiates, Clonidine) – Toxins (organophosphates) Cranial Nerve V • Sensory – Ophthalmic branch (sensory) • Cornea, conjunctiva, ciliary body, nasal cavity, sinuses, skin of eyebrows/forehead/nose – Maxillary branch (sensory) • Side of nose, lower eyelid, upper lip – Mandibular branch (mixed) • Sensory – skin of temporal region, auricles, lower lip/face, anterior 2/3 of tongue, mandibular gums/teeth • Motor - innervates the muscles of mastication • Cerebral lesion causes contralateral paresthesia • Most lesions affect all 3 branches Cranial Nerve V Testing • Inspect for tremor of the lips, involuntary chewing movements, and trismus • Compare muscle tension bilaterally with teeth clenched • Test tactile perception • Test sharp-dull discrimination • Test temperature perception • Test corneal reflex – Tests V & VII directly and VII consensually Cranial Nerve VII • Motor – Muscles of the face, scalp, and ears • Autonomic – Vasodilation – Secretion of submaxillary/sublingual glands • Sensory – Taste in anterior 2/3 of tongue – Ear canal/postauricular • Palsies can occur secondary to: – Polio, ALS, MS, tumors, syphilis, Lyme disease, Guillain-Barré Syndrome Cranial Nerve VII • Inspect for flaccid paralysis • Differentiate UMN vs. LMN – Elevate eyebrows – Close eyes – Show teeth – Whistle – Smile • **Central lesions causes contralateral paralysis to lower half of face (below the eyes) Cranial Nerve VIII • • • • Responsible for sense of hearing and balance Composed of the cochlear and vestibular nerves Sensory Test hearing Conductive loss Sensorineural loss Distortion of sound Minor Present with loss of upper tones Noisy environment Hearing may seem to improve Hearing typically worsens Patient’s voice Generally normal* Loud Ear canal/TM Visible abnormality Normal Weber Lateralizes to the impaired ear Lateralizes to the normal ear Rinne BC > AC AC > BC Cranial Nerve VIII • Look for spontaneous nystagmus • Romberg test/sign – Functional test of position sense • Stand with feet together • Close eyes and maintain for 20-30 seconds – Usually combined with a check for pronator drift • • • • As above Extend arms forward in supinated position Briskly move arms downward (separately) Arms should return smoothly to original position • Lesion causes – Unilateral deafness – Imbalance Cranial Nerve IX • Motor – Muscles of the pharynx • Autonomic – Vasodilation • Sensory – Taste in posterior 1/3 of tongue – Pharynx, tonsils, fauces, TM, posterior ear canal • Test for – Elevation of the uvula – Gag reflex – Mucosal anesthesia Cranial Nerve X • Motor, autonomic, and sensory functions – Palate, pharynx, larynx, neck, thorax, and abdomen • Branches to: – – – – – – – – Pharynx Larynx Esophagus Heart Bronchioles Stomach Liver Celiac • Perform indirect examination of the vocal cords • Lesion cause: – Hoarseness/aphonia – Dyspnea/stridor Cranial Nerve XI • Provides motor to – SCM – upper Trapezius • Testing: – Have patient shrug against resistance – Head rotation and movement against resistance Cranial Nerve XII • Motor to tongue • Testing: – Tongue movement • Midline • Tremors • Involuntary – Atrophy – Lingual speech • Paralysis causes deviation to the weak side Motor Function • UMNs – Transmit impulses from cortical nerve bodies to: • motor nuclei in brainstem (CNs) • Anterior horn cells of spinal cord • LMNs – Transmit impulses from anterior horn cells through anterior root into peripheral nerves – Terminate at the neuromuscular junction Motor Function • Inspection – Symmetry – Muscle bulk; size and contours; flat or concave; unilateral or bilateral; proximal or distal – Atrophy • Palpation – Muscle tone • Percussion – ? Fasciculations • Check motor strength • Body position (during movement and at rest) • Involuntary movements – Location, quality, rate, rhythm, amplitude and relation to posture, activity, fatigue, or emotions • If an abnormality exists: – Identify muscle(s) involved – Central vs. peripheral? – Learn muscle innervations Motor Function • Muscle tone – Slight residual tension in normal relaxed muscle – Feel muscle’s resistance to passive stretch • Muscle strength – – – – Wide variance - stronger dominant side Test by asking patient to actively resist movement If muscles too weak - test against gravity only or eliminate gravity If patient fails to move, watch or feel for weak contraction • Suspect decreased resistance? – Hold forearm and shake hand loosely • Resistance increased? – Varies or persists throughout movement Function and Innervations Muscle(s) Function Primary Nerve Origin DELTOID Shoulder abduction Axillary C5-C6 BICEPS Elbow flexion Musculocutaneous C5, C6 TRICEPS Elbow extension Radial C6, C7, C8 WRIST EXTENSORS Radial C6, C7, C8 WRIST FLEXION Median C6, C7 Median C7, C8, T1 FINGER ADDUCTION Median C7-T1 FINGER ABDUCTION Ulnar C8, T1 THUMB OPPOSITION Median C8, T1 HIP FLEXION Iliopsoas L2, L3, L4 HIP EXTENSION Gluteus maximus S1 HAND GRIP Grasp Fingers Function and Innervations Primary Nerve Origin Motor Function Muscles KNEE EXTENSION Quadriceps L2, L3, L4 KNEE FLEXION Hamstrings L4, L5, S1, S2 FOOT DORSIFLEXION Tibialis Anterior ANKLE PLANTAR FLEXION Gastrocnemius mainly S1 EXTENSION OF GREAT TOE Extensor hallicus longus L5 Deep peroneal L4, L5 Motor function • Always compare symmetry • Note any atrophy • Check muscle tone against resistance – Cogwheel rigidity = jerky, released in degrees – UMN paralysis = spasticity (increased tone) – LMN paralysis = hypotonia • Test muscle strength – Grade 0 to 5 Grading Muscular Response Grade Muscular Response 0 No contraction detected 1 Barely detectable flicker or trace of contraction 2 Active movement with gravity eliminated 3 Active movement against gravity 4 Active movement against gravity and some resistance 5 Active movement against resistance without evident fatigue - “Normal” Sensory Function • Fatigues quickly – Efficiency – Special attention to areas of: • Symptomology • Motor or reflex abnormalities • Trophic changes – Confirm with repeat testing!! • Patterns of testing: – Symmetrical – Distal vs. proximal: scattered stimuli – Vary pace Sensory Function Testing • Look for abnormality – map out boundaries in detail • Source of lesion • Distribution of sensory abnormalities and kinds of sensations affected • +/- motor/reflex abnormality • Demonstrate to patient before testing Spinothalamic Tract • Pain and temperature • Crude touch (light touch without localization) • Fibers cross & pass upward into thalamus Pain Sensation • Sharp safety pin or other tool • Demonstrate sharp & dull • Test by: – Alternating sharp & dull w/ pt’s eyes closed • Ask patient: – Sharp or dull? – Does this feel same as this? – Lightest pressure needed - do not draw blood Temperature • Often omitted if pain sensation normal • Two test tubes – filled with hot & cold water – or tuning fork heated or cooled by water Light Touch • Wisp of cotton • Touch lightly avoid pressure • Ask patient: – To respond when touch is felt – Compare one area with another Posterior Columns • Position and vibration • Fine touch • Synapse in medulla, cross & continue on to thalamus Vibratory Sense • 128 or 256 Hz Tuning fork • If impaired, proceed proximally Proprioception Grasp toe by sides - pull away from other toes Demonstrate “up” & “down” Tactile Localization • Have pt close eyes • Touch pt on R cheek & L arm • Ask patient where touch was felt Discriminative Sensations • Stereognosis, graphesthesia, two-point discrimination • Test ability of sensory cortex to correlate, analyze, & interpret sensations • Dependent on touch & position sense • Screen first with stereognosis - proceed to other methods if indicated Stereognosis • Ability to identify an object by feeling it • Place familiar object in patient’s hand & ask patient to identify it • Normally patient manipulates it skillfully & identifies it correctly Graphesthesia • Perform if inability to manipulate object • Ability to identify numbers written in hand • Use patient’s orientation Two-Point Discrimination • Touch two places simultaneously • Alternate stimuli • Avoid pain • Determine distance Spinal Reflexes: DTRs • Segmental levels of DTRs: – Supinator reflex – Biceps reflex – Triceps reflex – Abdominal reflexes - upper – - lower – Knee (Patellar) – Plantar responses – Achilles reflex C5, 6 C5, 6 C6, 7 T8, 9, 10 T 10, 11, 12 L2, 3, 4 L5, S1 S1 primarily Deep Tendon Reflexes: Grading Grade DTR Response 4+ Very brisk, hyperactive, with clonus Brisker than average, slightly hyperreflexic Average, expected response; normal Somewhat diminished, low normal No response, absent 3+ 2+ 1+ 0 Reflex Hammer - Incorrect Usage Jendrassik’s Maneuver • Reinforcement technique • Upper extremities – clench teeth – squeeze thigh • Lower extremities – lock fingers and pull one against the other Biceps Reflex C5,C6 Elbow Flexion Triceps Reflex C6, C7, C8 Elbow Extension Brachioradialis Reflex C5, C6 Forearm semiflexion/semipronation (NO wrist/hand flexion) Patellar Reflex L2, L3, L4 Knee Extension Achilles Reflex S1, S2 Ankle Plantar Flexion Plantar Reflex L5, S1, S2 Babinski Sign Abdominal Reflexes T8, T9, T10: ABOVE umbilicus T10, T11, T12: BELOW umbilicus Anal Reflex • Superficial reflex • Loss of anal reflex suggests lesion of S2,3,4 reflex arc • Possible lesion of cauda equina Clonus • Rhythmic Oscillation • Flexion/Extension • UMN Lesion Cerebellar Function • Requires integration of: – Motor system – Cerebellar system – Vestibular system – Sensory system • Assessed by: – Rapid alternating movements – Finger-to-Nose / Heel-to-Knee Test – Romberg’s Test – Gait Finger-to-Nose Test • Finger-to-nose with moving target • Stationary finger-to-nose with eyes closed Heel-to-Knee Test Rapid Alternating Movements • • • • First with hands Repeat with feet Diadochokinesia = ability to perform RAM Dysdiadochokinesis = slow, irregular, clumsy movements Station, Stance & Romberg’s Test • Station & Stance – Pt stand with feet together – First, eyes open • Romberg Test – Then, close eyes – If okay with eyes open, but sways w/ eyes closed = + Romberg – Mainly tests position sense • Vision can compensate for loss of position sense Pronator Drift • Often performed in conjunction with Romberg test • Pronator drift – Muscular strength – Coordination – Position sense Gait • Walk across room, turn and walk back • Tandem walking • Heel & toe walking • Hop in place • Shallow knee bend • Rising from sitting position or stepping up on stool Meningeal Irritation • Occur with meningitis & subarachnoid hemorrhage • Brudzinski’s Sign – Flex the head – Marked pain in the neck – Patient flexes hip and BLE • Kernig’s Sign – Pain when raising a straightened LE Lab/X-ray • • • • • CBC, CMP, U/A Specific drug levels Plain films of the spine CT of the brain & head MRI of the brain & spine – Greater resolution then CT for soft tissue/plaques • • • • • Angiography CSF exam EEG EMG & NCT PET/SPECT Spinal Studies Normal Skull Anatomy Normal L-Spine MRI CSF • Obtained through lumbar puncture • Indications: – Suspected CNS infection (i.e. syphilis) – Suspected subarachnoid hemorrhage • Contraindicated if cerebral mass/lesion is suspected • Measure opening pressure • Obtain samples for cell counts, glucose, protein level, and cultures Computed Tomography • • • • Gives adequate information about brain anatomy Used primarily to detect hemorrhage & tumors Can be performed with/without contrast Indications: – – – – – – – – – Focal neurologic deficits Altered mental status Head trauma New-onset seizure Increased ICP Suspected mass lesion Suspected subarachnoid hemorrhage (with contrast) Abscess, intracranial tumor (with contrast) Chronic subdural hematoma, infarct, vascular malformation Review of Neurological Exam • Six categories: – Mental status & speech – Cranial nerves – Motor function – Sensory function – Reflexes – Cerebellar function • Carefully evaluate the hx of the CC • CN assessment is essential! Summary • Select appropriate questions to elicit from the patient with a neurological complaint during a patient interview • Differentiate “normal” from “abnormal” findings on neurological examination – – – – – Identify common causes of various cranial nerve palsies Differentiate conductive hearing loss from sensorineural hearing loss Differentiate amongst the various movement disorders Differentiate atrophy, hypertrophy, and pseudohypertrophy. Differentiate between spasticity, rigidity, and flaccidity, and identify common causes of each. • Determine location of neurological lesion – Differentiate upper motor neuron lesions from lower motor neuron lesions – Differentiate CNS disorders from PNS disorders, and identify location of the lesion & common causes. • Compare and contrast the five clinical levels of consciousness.