Short Course       [Return to MD Home Page]

How to Think Like a Neurologist.

Part 1: Pearls of the Neurological Examination

By

Martin L. Kutscher, MD. Departments of Pediatrics and Neurology,
New York Medical College, Valhalla, NY

Introduction

This brief course starts with the physical examination, with emphasis on useful "pearls." Tests of particular utility are printed in italics; they are summarized in Table 1 below. A full pediatric neurological examination is summarized in Table 2.


Table 1. Some of the Best Screening Tests in the Pediatric Neurological Examination.

  • Mental state: level of consciousness
  • Cranial N.: fundoscopic examination
  •     pupils
  •     extraocular movements
  • Motor: drift and triceps
  •     (for upper extremities) extensor hallicus and dorsiflexors
  •     (for lower extremeties)
  • Reflexes: deep tendon reflexes
  • Cerebellar: rapid alternating movements
  • Gait:  regular, toe, heel, tandem
  •     running and turning

 The Neurological Examination

Mental Status

The child’s level of consciousness is probably the most important part of the neurological examination of the acutely ill child, as alterations in the level of consciousness will often be the first manifestation of a problem.

A great way to awaken people is to get them upright. The standing position is even better than sitting. Humans have an alerting reflex in the vertical position—the same reflex we utilize in newborns when we tilt them upwards so that they open their eyes. Conversely, when people are in the reclining position, they are ready to sleep.

 

 

Describe level of consciousness. Amplify on words like "lethargic" which mean different things to different examiners. I like to use a sentence which describes four states:

  • Patient’s activity as you enter the room, such as chatting, sleeping, posturing, etc.
  • Stimulus required to awaken patient, such as calling her name, pinching, etc.
  • Patient’s best mental state seen, such as chatty conversation, sluggish answers, semi-purposeful movements, etc.
  • Patient’s activity when you stop stimulating her.

Ask, "Is your child acting like him/herself?" Always listen to the mother. It is okay to assess the child as sicker than the mother feels, but it may be risky for the doctor to assess the child as less sick than the mother thinks.

Spell "WORLD" backwards. This activity taps into large areas of cortex, including language, memory, and executive function. Seeing a child groaning on a stretcher, yet able to do this, is a reassuring sign that cognitive abilities are largely preserved—at least at present.

Four Part Command. Say: "When I say ‘go,’ then I want you to close your eyes, stick out your tongue, and put your left hand on your right ear." Many children will still have some left/right confusion with this test (especially children less than ten years old).

Oriention. Usually orientation to person, place and time are lost in the opposite order.

Memory. Age appropriate tests might include immediate (digit span forwards and backwards), short term (food for breakfast), and long term (name of teacher or school).

Developmental, speech, academic, and psychiatric mental status exams are covered in appropriate textbooks. Here, we have focused on evaluation of the mental status in the acute setting.

Cranial Nerves

Avoid "2-12 intact" as well as "WNL," both of which frequently mean "We Never Looked." Rather, document what was explicitly observed.

I (Olfactory) nerve. Not routinely tested.

II (Optic) nerve

Fundoscopic Exam. The key to seeing the optic disc is the child’s visual fixation at a point straight ahead and 15 degrees up. Have the young child fixate on the mother, who often needs to be exceptionally animated in order to get the youngster’s attention. Sometimes, it helps for the child to point at the target with their finger or a flashlight. If you are having trouble finding the disc, do not despair. First, examination of the rest of the fundus is important anyway, especially to look for retinal hemorrhages. Second, be patient. If you got a brief but incomplete look, stay where you are. When the child re-fixates, the disc will come back into view. Third, when you find a vessel, just follow it. If it is getting smaller, you are going in the wrong direction. Otherwise, all vessels lead to the optic discs.

Describe:

Disc sharpness refers to the sharpness of the distinction between the yellow optic disc and the pink retina.

Disc flatness refers to whether or not the optic disc is mounded up when it comes out of the retina. When the disc is elevated, the vessels may be noted to course downwards as they traverse over the optic disc.

Disc color and retinal vessels.

Spontaneous venous pulsations (SVPs.) While acute papilledema may take 48 hours or more to manifest itself, the first sign is usually loss of SVPs. Their presence is reassuring that there is probably no significant elevation of intracranial pressure at this moment. This does not mean that there is no serious intracranial pathology, nor that there will not be signs and symptoms of raised pressure later. Note that SVPs may not be detected in many normal patients.

PERRL means Pupils Equal, Round, Reactive to Light. If you also can also check the response to Accommodation, write PERRLA. While Cr. N. II is the sensory limb of this reflex, Cr.N. III is the motor limb. [Although pupil reactivity is a critical part of the exam, "blowing a pupil" is a late sign! Mental status changes are much more likely to be useful early warning signs.]

Visual acuity. If the visual acuity can be demonstrated to be normal through a pinhole, glasses, the near card, or the distant chart, then the acuity disturbance it is unlikely to be of primary neurological origin.

Visual fields

 

Normal optic disc.
Alternate moving your cursor over the picture, and then off again.
This will simulate "spontaneous venous pulsations" ( just below the black circle marker).

 

papill.jpg (13653 bytes)

Severe Papilledema.
Note retinal hemorrhages.

 

III (oculomotor), IV (trochlear), and VI (abducens) nerves are involved in the extraocular movements (EOMs). VI controls the lateral rectus (abducts the eye), IV controls the superior oblique (pulls the eye down and in), and III does all other extraocular movements. There are 9 directions of gaze: left: up, horizontal, down;  straight: up, horizontal, down;   &right: up, horizontal, down.

Eye Palsy simulation page. Very cool demonstration of any extraoccular palsy.

 

V (trigeminal) nerve function includes:

Facial sensation

Corneal sensation (the afferent limb of the corneal reflex)

Muscles of mastication (masseter)

VII (facial) nerve includes:

Facial movement. Upper motor neurons send innervation to both sides of the upper face (eye closure and forehead wrinkling) but only to the contralateral part of the lower face. Thus a "central 7th" tends to spare the upper part of the face. In contrast, lower motor neuron lesions (such as Bell’s palsy) affect the final common pathway and thus involve muscles of both the lower face and upper face.

Taste on anterior 2/3 of tongue

Chordae tympani which dampens loud sounds. Loss of this function causes hyperaccusis, which is the symptom of sounds seeming too loud. Test for this by placing a stethescope in the patient’s ears and then asking if one side seems too loud when you scratch the stethescope’s diaphragm. Hyperaccusis should not be confused with tinnitus (ringing in the ears) or hearing loss, which are VIII nerve symptoms.

 

VIII (cochlear) nerve

Hearing testing

IX (glossopharyngeal), X (vagal) nerves

Gag reflex

XI (spinal accessory) nerve

Sternocleidomastoid (turns head to the opposite side)

Trapezius (shrugs shoulder)

XII (hypoglossal) nerve

Tongue protrusion forward and to the sides.

Tongue fasciculations seen in anterior horn cell disease.

Motor Examination

Careful observation of the child’s activity.

Pronator Drift. This is a superb and sensitive test for upper motor neuron weakness. It will often detect weakness missed on manual motor testing—and it is quick. Use this test all of the time. First, the child extends his arms palms down. Then, the eyes are closed, and a few seconds later, the child turns his arms palms up. During this turning maneuver, a child with upper motor neuron weakness may pull the elbow down and in. Finally, observe the arm position when the palms are up. The eyes should remain closed. Observe for any asymmetric pronation, drift, or finger flexion. Mild symptoms may be provoked by asking the patient to shake his head "no."

                                       PEdrift24.jpg (14505 bytes)    PEdrift14.jpg (16028 bytes)

Pronator Drift:   Start with hands palm down, then turn palms up.

 

Manual motor testing can usually be done with children starting around five years of age. Test flexion and extension at each joint. In a central lesion, the weakest muscles will be the extensors in the upper extremities and the flexors in the lower extremities. So, rather than focusing on the grip, screen for upper extremity weakness by testing the triceps and drift. For the lower extremities, the extensor hallicus (great toe extensor) and ankle dorsiflexors (pulling the foot up at the ankle by asking the child to "reel in the fish") are the best screening tests for upper motor neuron lesions. Muscle weakness can best be detected if the muscles are tested at mechanical disadvantage, i.e., starting with the muscle fibers stretched. For example, test the triceps starting with the elbow flexed, and then asking the patient to push away.

 

PEtriceps4.jpg (9438 bytes)              PEwrist4.jpg (8763 bytes)              PEankle4.jpg (7266 bytes)

Triceps Testing                              Wrist Extensor Testing                 Ankle Dorsiflexion Testing

 

Functional motor tests, such as getting up from the ground, using stairs, and gait testing have several uses. First, they may be the best way to pick up proximal weakness, such as seen in myopathies. Second, they may be the only way to gain the cooperation of younger children. Third, functional tests can often be used as developmental landmarks. These include the parachute (child puts arms out when tilted forward by 12 months age), and then the wheelbarrow. Asymmetry of these reflexes may indicate focal weakness.

Muscle tone and bulk. Distinguish between the peripheral muscle tone (the tone of the extremities) vs. truncal tone (which includes pelvic tilt, posture, tendancy to fall through the examiner’s hands, and jaw tone). A common pattern in static motor encephalopathy is hypertonia in the extremities (especially the legs) and truncal hypotonia including lax jaw tone.

Sensory Testing

Light touch is the most commonly tested sensation but least reliable screen since it is carried by multiple spinal cord columns.

Pain and temperature are carried by the spinothalamic tract in the spinal cord.

Position sense and vibration are carried by the posterior columns.

Cortical sensation by the parietal cortex can be tested if the above primary sensory modalities are intact. Double simultaneous distinction, graphesthesia, and stereognosis are most commonly checked.

Reflexes

Deep tendon reflexes.

Babinski response can be present (toes up with flaring) or absent. They should always be symmetric, but can be present or absent up to one year of age. Primary reflexes such as the Moro, root, and atonic neck should not be present after six months of age.

Cerebellar

Rapid alternating movements may be awkward with both cerebellar and upper motor neuron problems. They should be tested each side individually. Otherwise, the good side may slow down to match up with the problem side, masking the difficulty.

Finger to nose

Heel to shin

Rhomberg

Gait

Along with fundoscopy and the drift, this is an essential test in medically stable patients. Gait testing not only checks for midline cerebellar dysfunction, but it is also a fantastic screening test for weakness. Watch the arm swing, hip movement, broadness of gait, and heel strike.

Regular walking. A young child is more likely to cooperate if expected to walk towards the mother first, rather than towards yourself. If the mother puts her arms out, then the child will put out her arms also, eliciting a type of drift test.

Heel walking. (This is particularly difficult in upper motor neuron diseases.) It is easier to observe if done while the child walks towards you.

Toe walking is easier to observe if done while the child walks away from you.

Tandem walking.

Running, including rapid turns, is an even better test.

The General Examination

Certain elements of the general physical examination are of particular interest. These include examination of the:

Skull (including bruits over the temples, mastoids, and orbits. Hemotympanum may be found in head trauma.)

Head circumference

Sinuses and mastoids

Neck (including carotid thrills and bruits, especially in trauma.)

Liver/Spleen

Spine (including dimples, birthmarks, or hair tufts. These lesions may signify underlying tracts or spinal cord pathology.)

Skin


Table 2. Summary of the Pediatric Neurological Examination

General: Skull (bruits)

Head Circumference

Mastoids/sinuses

Neck

Liver/spleen

Spine

Skin

Neuro: Mental Status: Level of consciousness (incl. 4 part commands; spell world backwards)

Orientation

Memory

Intellect

Speech and language

Cranial Nerves

II Visual acuity; visual fields; PERRLA, pupils; disc; SVPs; fundus

III, IV, VI EOMs in 9 fields of gaze

V Facial sensation; chewing

VI I Facial movement [peripheral 7th involves forehead]

VIII Hearing

IX, X Gag

XI Trapezius/SCM

XII Tongue [fasciculations in anterior horn cell disease]

Motor: Manual motor testing (> 5 years old)

drift

flexion/ext. at each joint, starting with muscle at disadvantage

especially triceps, ankle and toe dorsiflexors

tone

Functional testing

observation

walking/crawling (having mother extend arms elicits drift)

stairs

Gower's

parachute/wheelbarrow

Sensory: Light touch (least reliable)

pinprick/temperature

position sense/vibration

cortical sensation (2 pt discrimination; graphesthesia, stereognosis)

Reflexes: DTRs

Babinski response

Cerebellar: Finger to nose

Heel to shin

Rapid alternating movements (test each side separately)

Gait: Regular, toe, heel, tandem, running, turning

 

 

Detailed descriptions of the (adult) neurological exam can be found at:

http://www.neuroexam.com/ which has videos of each part of the exam!

http://www.medinfo.ufl.edu/year1/bcs/clist/neuro.html#AA22

 


Return to MD Home Page

Up ] [ Neuro Exam ] Approach to Diagnosis ] Acute Hemiparesis ] ADHD Spectrum ] AutisticSpectrum ] Headaches ] Psych Sx: Causes ] Seizures ] Status Epilepticus ] Seizures: Febrile ] Infantile Spasms ] JME of Janz ] Elective Schedule ] Syllabus ] Sleep Disorders ]

 

 

 

 

 

 

Hit Counter