Abstract

Neurological examination is the assessment of mental status, cranial nerves, motor function, sensory function, coordination, and gait for the diagnosis of neurological conditions. Findings should always be compared with the contralateral side and upper limb function should be compared to lower limb function to determine the location of the lesion. This learning card provides information about several examination methods and explains a selection of neurological terms used in the evaluation of neurological conditions.

Mental status examination

Levels of consciousness

Types of impaired consciousness
- Somnolence
  - A state of drowsiness; from which a patient can be easily aroused.
  - Patient responds normally; except for a slight delay when addressed.
- Stupor
  - A state of insensitivity bordering on unconsciousness; from which the patient is not easily awoken except if exposed to strong external stimuli; (e.g., if addressed in a loud voice) and into which the patient returns in the absence of further stimuli.
  - Communication is not possible; and painful irritation provokes withdrawal response.
- Coma: Patient cannot be aroused and there is no response to stimuli.
Glasgow Coma Scale (GCS) quantifies the degree of impaired consciousness

Assessment cognitive decline or dementia

Full mental status examination components include:
- Appearance (e.g., groomed, well dressed)
- Behavior (e.g., cooperative, agitated)
- Orientation (e.g., to person, place, time)
- Mood and affect (as well as congruency)
- Thought content (e.g., delusional) and process (e.g., logical thinking)
- Memory (e.g., short-term vs. long-term memory, assessed by asking the patient to recall a number of objects immediately and again after a few minutes)
- Ability to perform simple calculations (e.g, simple multiplication; determine if appropriate for level of education)
- Insight and judgement (ask patient what they would do in a realistic situation, e.g., if they found a stamped envelope)
- Higher cortical function (e.g., ask patients to explain the meaning of well-known idioms)
- Determine levels of consciousness
Mini-mental status examination (MMSE)
Saint Louis University Mental Status Examination (SLUMS)

Findings

Hemineglect
- Inability to respond to unilateral stimuli due to a brain lesion (not due to a primary motor or sensory lesion)
- The lesion is usually contralateral to the stimuli
  - Motor neglect
  - Sensory or perceptual neglect
Amnesia: loss of memory (e.g., time, content)
- Retrograde
- Anterograde
- Global
Aphasia: Inability to communicate (impairment of the ability to either form or understand words)

		Location of lesion	Clinical features
Broca aphasia (motor aphasia, expressive aphasia)		Broca area, frontal lobe	Telegraphic and grammatically incorrect speech Comprehension is largely spared (difficulty understanding complex language may occur)
Wernicke aphasia (sensory aphasia, receptive aphasia)		Wernicke area, temporal lobe	Word salad (neologisms, meaningless speech) Comprehension is impaired The patient is unaware of these deficits
Global aphasia		Broca area, Wernicke area, and arcuate fasciculus	Severe impairment of speech expression and comprehension Patient may be mute Patient may only utter sounds Inability to comprehend verbal commands
Conduction aphasia (associative aphasia)		Arcuate fasciculus of the parietal lobe	Preserved comprehension but cannot encode phonological information for production Impaired repetition with paraphasia (they substitute or transpose sounds), which patients try to correct
Anomic aphasia		Usually, pinpointing the localization of the lesion is not possible.	Difficulty finding words Paraphrasing occurs when patients cannot find the word they seek.

Transcortical aphasia	Motor	Supplementary motor area (SMA) in the cortex, with Broca area intact (exception: may occur during recovery phase of Broca aphasia)	Difficulty initiating speech Difficulty in expressing a thought process Difficulty producing own phrases
Transcortical aphasia	Sensory	Various areas of the temporal lobe, with Wernicke area intact	Impaired speech expression and comprehension Intact echolalia Errors in paraphrasing Poor comprehension

Apraxia: difficulty performing targeted, voluntary movements despite intact motor function
- Ideomotor apraxia: difficulty imitating actions; intended expression and gestures do not match
- Ideational apraxia: difficulty completing multistep actions.
- Visual motor apraxia: difficulty picking up objects placed in the contralesional visual field.
Agnosia: Visual and auditory recognition is impaired (no elementary deficits in the sensory system)
- Tactile agnosia (astereognosis): Impaired ability to recognize or identify objects by touch alone; visual recognition is unimpaired.
- Visuospatial dysgnosia: inability to orient oneself in space
- Prosopagnosia: inability to recognize familiar faces
- Autotopagnosia
Anosognosia: inability to recognize neurologic impairment
Pure alexia: : form of visual agnosia with severe reading problems; , as a result of interrupted connections between the visual cortex and language‑related areas.
Acalculia: inability to perform simple calculations (parietal lobe lesion)
Agraphia: inability to write

References:^[1]^[2]^[3]

Cranial nerve examination

For information on disorders of the cranial nerves, see cranial nerve palsies.

Cranial nerve		What is examined?	How is the test performed?
Olfactory nerve	I	Olfaction	The patient is exposed to aromatic substances (e.g., coffee) and asked to identify the odor
Optic nerve	II	Vision	The patient is asked to identify objects/letters from predefined distances.
		Visual field	The examiner wags a finger towards the patient's visual field from all sides.
		Pupillary light reflex	The examiner shines a light into the patient's eye (e.g., a penlight). A prompt, consensual response should normally be observable. Pupillary shape and width: Healthy pupils are isocoric and of medium width; anisocoric and/or narrow/wide are suggestive of a disorder (see pupillary disorders).
		Papilla	Fundoscopic examination (e.g., a pale optic disk is indicative of optic nerve atrophy)
Oculomotor nerve, trochlear nerve, abducens nerve	III, IV, VI	Eye movement	Patients are asked to follow a finger moving up, down, laterally, and diagonally with they eyes. Observe if paresis, nystagmus, or alterations of smooth pursuit appear.
		Visual accommodation	The physician moves a finger towards the patient. If visual accommodation is intact, the finger is clearly visualized by the patient at all times.
		Eyelid ptosis (Levator palpebrae superioris muscle dysfunction)	The patient is asked to open and close the eyes.
Trigeminal nerve	V	Facial sensation	The examiner lightly touches three distinct facial areas (the forehead, cheek, and jaw ). Normally, light touch should be felt by the patient in all three areas. If this is not the case, tests for abnormalities of other sensory modalities (e.g., pain, temperature) should be performed.
		Muscle function (muscles of mastication)	The patient is asked to open and close his/her mouth; at the same time, the examiner palpates the masseter muscle.
		Reflexes	Masseter reflex (jaw jerk reflex) A finger is placed on the patient's chin, while the patient's mouth remains slightly open Tapping with a reflex hammer normally induces jaw closure If jaw closure is increased, suspect an UMN lesion Corneal reflex The cornea is lightly touched with a cotton swab (approaching slowly and sideways from the lid edge) → Touch normally induces closing of the eyelid.
Facial nerve	VII	Motor function (muscles of expression)	If motor function is intact, the patient should be able to perform the following: Forehead wrinkling Closing the eyes tightly Nose wrinkling Inflate the cheeks Smiling (showing teeth) Whistling
Facial nerve	VII	Sense of taste	If the sense is intact, the patient should be able to taste sweet, salty, and sour food/drinks.
Vestibulocochlear nerve	VIII	Hearing	Basic hearing test: normally, the patient should be able to hear two fingers rubbing together before the external acoustic meatus (ear canal). The Weber test and Rinne test allow sensorineural hearing loss to be differentiated from conductive hearing loss (see ENT diagnostic testing).
Glossopharyngeal nerve and vagus nerve	IX, X	Palatal movement	The physician performs a visual inspection of the uvula and soft palate: asymmetry and uvula deviation indicate impaired innervation Gag reflex (pharyngeal reflex): Normally, evoked by approaching the uvula quickly and carefully with a spatula/long cotton swab on each side. Absence of the gag reflex is indicative of nerve damage
		IX only: sense of taste	The patient patient is given a bitter substance to taste: no sense of taste indicates impaired innervation.
		X only (recurrent laryngeal nerve): vocalization	In case of lesion, the patient would have hoarseness or bovine cough.
Accessory nerve	XI	Trapezius muscle and sternocleidomastoid muscle (motor function)	Trapezius muscle: the patient's shoulder is elevated against resistance Sternocleidomastoid muscle: the patient's head is rotated against resistance
Hypoglossal nerve	XII	Tongue muscles (motor function)	The tongue should be pressed against the cheek from the inside, while the examiner tests the strength by pushing from the outside. Hypoglossal nerve paralysis: when the patients stick out the tongue, it moves towards the impaired side

References:^[2]

Motor function

Upper motor neuron (UMN) injury vs. lower motor neuron (LMN) injury
	Upper motor neuron lesion (UMN damage)	Lower motor neuron lesion (LMN damage)
Definition	Lesion along the descending motor pathways (corticospinal tract or pyramidal tract) Typically before the anterior horn cell of the spinal cord or motor nuclei of the cranial nerves (e.g., along motor cortex, brain stem)	Lesion anywhere along the nerve fibers between the ventral horn of the spinal cord and relevant muscle tissue
Muscle appearance	Atrophy is absent	Atrophied Fasciculations
Characteristics	Central paresis (spastic paresis): pyramidal tract signs ↑ Tone, spasticity, and clonus ↓ power in muscle groups ↑ reflexes	Peripheral paresis (flaccid paresis): absent pyramidal tract signs ↓ Tone ↓ Power in single muscle fibers ↓ reflexes/areflexia
Bladder function	Detrusor hyperreflexia and detrusor/external urethral sphincter dyssynergia	Overflow incontinence
Special tests	Positive Babinski sign (toes point upward, abnormal) Pronator drift test The patient is asked to raise both arms horizontally up to shoulder level, palms facing upwards, with the eyes closed (for 30 seconds) Lowering or pronation of one arm is indicative of paresis. Mingazzini test The patient is asked to lie in the supine position, with eyes closed, and is asked to raise and hold both legs for 30 seconds (90° angle at knee and hip). Lowering of one leg is indicative of paresis	Absent Babinski sign (toes neutral or point downward, normal)
Common etiologies	Multiple sclerosis, tumor, stroke, Vitamin B₁₂ deficiency, ALS (both UMN and LMN signs)	Peripheral neuropathies, poliomyelitis (poliovirus), ALS (both UMN and LMN signs)

Muscle appearance

Assessment: inspection and palpation of muscle groups
Findings
- Fasciculation: involuntary, asynchronous contraction of muscle fascicles within a single motor unit; usually benign but can signify a lower motor neuron lesion
- Tenderness
- Abnormal movements (e.g., tremor, tic, myoclonus)
- Abnormal posture
- Atrophy or hypertrophy (examined bilaterally)
  - Muscle groups are measured to compare specific differences in size.
  - In neurologic disorders, the small hand muscles are often affected by atrophy.

References:^[2]

Power

Definition: maximal effort a patient is able to exert from an individual muscle or group of muscles
Assessment
- The patient is asked to flex and extend extremities against resistance
- Muscle power tests should be performed bilaterally for comparison
Muscle power grading
- 0 = no contraction (paresis)
- 1 = flicker or trace of contraction
- 2 = active movement, with gravity eliminated
- 3 = active movement against gravity
- 4 = active movement against gravity and resistance
- 5 = normal power

References:^[4]

Reflexes

Tendon reflexes

Definition: : stretch, monosynaptic reflexes
Assessment
- During reflex testing, the patient should be relaxed (at least the muscles involved in the reflex test should be relaxed). (→ also see: radiculopathy)
- Elderly patients may have reduced or absent lower deep tendon reflexes due to normal aging-related changes in muscles and tendons

Nerve root		Tendon reflex	Test
Upper limbs	C5–C6	Biceps reflex	First, the examiner places his/her thumb on the patient's biceps tendon, then the examiner strikes his/her thumb with a reflex hammer and observes the patient's forearm movement.
	C5–C6	Brachioradialis reflex	Striking the lower end of the radius with a reflex hammer elicits movement of the forearm.
	C7–C8	Triceps reflex	The examiner holds the patient's arm (forearm hanging loosely at a right angle) and taps the triceps tendon with a reflex hammer to induce an extension in the elbow joint.
	C7–C8	Finger flexor reflex	This reflex is induced by tapping the terminal phalanx of a relaxed finger on the palmar side, while the examiner holds the patient's hand in level with the proximal phalanges. The test is positive when there is significant flexion in the terminal phalanx of the tapped finger and the thumb, or when the flexion is very asymmetrical comparing both hands.
Lower limbs	L2–L4	Adductor reflex	Tapping the tendon above the medial condyle of femur elicits the adductor reflex.
	L2–L4	Knee reflex	Striking the tendon just below the patella (leg is slightly bent) induces knee extension.
	L5	Posterior tibial reflex	The tibialis posterior muscle is tapped with a reflex hammer, either just above or below the medial malleolus. The reflex is positive when an inversion of the foot occurs.
	S1–S2	Ankle reflex	Striking the Achilles tendon with a reflex hammer elicits a jerking of the foot towards its plantar surface. Alternatively, the reflex is triggered by tapping the ball of a foot from the plantar side.

Superficial reflexes

Definition: polysynaptic reflexes elicited by stimulation of the skin
Superficial reflexes are divided into two subgroups:
- Physiological reflexes
- Pathological superficial reflexes: in case of central motor neuron damage, the reflex response decreases.

Nerve root	Reflex	Test
T6–T12	Abdominal reflex	Abdominal reflexes are tested with the patient lying down. The anterior abdominal wall is lightly stroked with a spatula from lateral to medial (bilaterally) in following areas: below the coastal arch around the umbilicus above the inguinal ligament A normal response is a contraction of the abdominal muscles, while the absence of contractions is indicative of nerve root damage.
L1–L2	Cremasteric reflex	The reflex is elicited by stroking the medial, inner part of the thigh. A normal response is a contraction of the cremaster muscle that pulls up the testis on the same side of the body.
S3–S5	Anal reflex	Stroking the skin around the anus with a spatula elicits the anal reflex, which results in a contraction of the anal sphincter muscles.
S3–S5	Bulbocavernosus reflex	The reflex is elicited by squeezing the glans penis or clitoris, resulting in contractions of the pelvic floor muscles.

Primitive reflexes

Brief description: Reflexes that are are normal in newborns and infants, but not in adults, where they may appear in case of diffuse brain injury due to lack of common inhibiting factors

	Test
Sucking reflex	Stroking the mouth induces sucking activity.
Palmar grasp reflex	Stroking the palms elicits finger flexion.
Palmomental reflex	Stroking the ipsilateral thenar eminence from proximal to distal induces a short involuntary contraction of the mentalis muscle.

Corticospinal tract signs

Brief description
- Corticospinal tract signs are indicative of damage to the pyramidal tract.
- Babinski sign is the most common and thus most reliable pyramidal tract sign.
- These reflexes occur physiologically in healthy infants

	Test	Sign
Babinski sign	The examiner strokes the sole of a patient's foot on the lateral edge using, e.g., the handle of a reflex hammer	The sign is positive (pathological) when the big toe extends (dorsiflexes), while the other toes fan out. The test is inconclusive when only the big toe responds.
Gordon sign	The examiner compresses the calf muscles

Babinski sign, although normal in newborns and infants, is always pathological in adults!

Do not confuse clonus with myoclonus! Myocloni are arrhythmical and sudden jerks of a muscle or group of muscles while cloni are rather rhythmic and repetitive contractions and relaxations of a muscle group!

Tone

Definition: resistance of an individual muscle (or a group of muscles) to passive stretching
Assessment: passive movement of the extremities

Tests
	Upper limb	Lower limb
Tone	Elbow: The examiner flexes and fully extends the patient's elbow. Forearm: (while elbow in 90° position) The examiner supinates and pronates the patient's hand. Wrist: The examiner flexes and extends and then twist the patient's wrist from side to side.	The patient is asked to relax the limbs while lying in the supine position and then roll the legs from side to side.
Spasticity	Velocity-dependent phenomenon The clasp-knife phenomenon: initial resistance due to increased muscle tone is followed by a sudden decrease in resistance.	The arm of the examiner is placed under the patient's knee and the examiner briskly lifts the patient's limb → increased muscle tone in limb
Rigidity	Velocity-independent phenomenon Cogwheel rigidity: A resistance resembling a cogwheel movement is observed when the joint of a patient's extremity is moved by the examiner.	Stiffness and/or inflexibility regardless of movement
Clonus	Wrist: The examiner hyperextends the patient's wrist.	Patellar clonus: The examiner grasps the patient's patella between the index finger and the thumb, quickly pushes it down distally, and then holds it in this position. Foot clonus The examiner holds the patient's leg, with both knee and ankle resting in a 90° flexion. Then the examiner proceeds to dorsiflex and partially evert the foot forcefully multiple times while sustaining the pressure. Clonus is seen as a set of involuntary contractions.

Sensation

	Pathway	Assessment	Finding
Light touch	Dorsal columns	To test for symmetry of touch sensation, the examiner touches the patient's body at different locations bilaterally. In cases of suspected radicular lesions, the particular dermatome should be examined individually. . In cases of suspected peripheral nerve lesions, diagnostics should involve checking the areas innervated by the corresponding sensory nerves.	Paresthesia Dysesthesia Allodynia
Pain and temperature	Spinothalamic tract	Implements such as a broken spatula can be used to test pain sensation bilaterally (e.g., by gently prodding the patient with the object). Temperature sensation is tested using two objects of different temperatures (e.g., two test tubes with cold and warm water).	Decreased (hypoalgesia) or increased (hyperalgesia) sensitivity to nociceptive stimuli
Pallesthesia (vibration sense)	Dorsal columns	A tuning fork is hit and placed on a bony projection (e.g., medial malleolus). The vibration amplitude and thus the vibration intensity decrease over time. The patient reports when the vibration stops.	Abnormalities of vibration are described as mild, moderate, or severe loss of vibration sense. Loss of vibration sense may also indicate a peripheral neuropathy or myelopathy.
Proprioception (joint position)	Dorsal columns	To test proprioception, the most distal joint of the big toe or the distal interphalangeal joint of the thumb are held by its sides and moved up and down. The patient should be able to identify the positional change with eyes closed.	Abnormalities of proprioception suggest peripheral polyneuropathy or myelopathy.

See also “Overview” in incomplete spinal cord syndromes.

References:^[2]^[5]

Coordination

Definition: ability to coordinate fluid movements
Assessment
Findings
- Dysmetria
- Dysdiadochokinesia
- See also cerebellar syndromes.

References:^[2]

Gait assessment

Evidence for vestibular disorders, sensory or cerebellar ataxia (see “Diagnostics” in cerebellar syndromes)
Assessment
- Observation of casual gait: The patient is asked to walk a few steps forwards and backwards.
  - Normal gait: steady, natural arm swing
  - Abnormal gait: broad-based or unsteady gait, short-stepping gait
- Balance test: The patient is asked to place one foot directly in front of the other as if walking on a tightrope
- Foot drop test: The patient is asked to walk on their heels (impossible in the case of deep fibular nerve lesions)
- Walking on tiptoes (impossible in the case of tibial nerve lesions)

	Description	Examination	Result
Romberg test	Test for assessing ataxia (vestibular, sensory, or cerebellar ataxia) May help to distinguish between sensory and cerebellar ataxia.	The patient is asked to stand with both feet together, raise the arms, and close the eyes.	Positive Romberg: closing the eyes impairs coordination (patient starts swaying, or swaying increases), which is indicative of sensory ataxia. Negative Romberg Closing the eyes does not affect patient's balance (patient's swaying does not increase). Uncontrollable swaying, even with eyes open, is indicative of cerebellar ataxia. An increased tendency to fall sideways after closing the eyes indicates a vestibular disorder.
Unterberger test	Test for vestibular or cerebellar lesions	The patient is asked to walk on the spot with their eyes closed for 50 paces.	The test is positive when the patient rotates more than 45° around his/her central axis, which is indicative of a cerebellar lesion or vestibular impairment.
Trendelenburg sign	Tests for neurological insufficiency of the gluteus medius and gluteus minimus muscles, which are innervated by the superior gluteal nerve	The patient is asked to stand on one leg	Physiological: when standing on one leg, the pelvis remains level (no compensatory movements of the upper body) → Negative Trendelenburg sign Pathological: pelvic drop towards the unimpaired, unsupported side → Positive Trendelenburg sign Duchenne sign: torso tilting towards the contralateral side compensates the pelvic drop on the unimpaired side. Duchenne limp: the Duchenne sign (frequently occurs bilaterally) results in a compensatory to‑and‑fro movement of the torso during walking

Signs of meningeal or nerve root irritation

Meningism

Definition: triad of nuchal rigidity; , headache; , and photophobia, associated with irritation of the inflamed meninges and/or spinal nerves
Examination: The examiner passively flexes the neck of the patient lying in the supine position.
Causes: subarachnoid hemorrhage; (SAH), bacterial meningitis, etc.

Additional signs of meningeal or nerve root irritation

Lasègue sign (root L5–S1)
Kernig sign: : in a supine patient, painful passive extension of the knee when the thigh is flexed at the hip (knee at a 90° angle)
Brudzinski sign
- Involuntary lifting of the legs provoked by passive flexion of the neck in a patient in supine position
- Lifting of the legs reduces pain associated with tension of the irritated meninges and, especially, the lumbosacral spinal nerves during neck flexion