CALDERON, GARCIA, HARDIN, MANABAT, SOLIS 1 of 5

REFLEX TESTING

2.3-C August 11, 2014

PLM CM Dr. Guzman

Legend: normal text lecture/old trans; Bates italics; transers notes red text.

THE NEUROLOGIC EXAM

Steps in the Diagnosis of Neurologic Diseases: 1. Mental Status Exam 2. Gait and Station

3. Cranial Nerves 4. Motor System 5. Coordination 6. Reflexes 7. Sensation 8. Head and Neck

9. Spine and Skin

DEEP TENDON REFLEXES

Also muscle stretch reflex Monosynaptic (e.g., DTR of arms and legs) involves one

afferent (sensory) and one efferent (motor) neuron across a single synapse

Simplest unit of sensory and motor function

Relayed over structures of both central and peripheral nervous systems

SEGMENTAL LEVELS

You can remember them easily by their numerical sequence in ascending order from ankle to triceps: S1-L2, L3, L4-C5, C6, C7.

Ankle reflex Sacral 1 primarily

Knee reflex Lumbar 2,3,4

Supinator (brachioradialis) reflex

Cervical 5,6

Biceps reflex Cervical 5,6

Triceps reflex Cervical 6,7

ELICITING THE DEEP TENDON REFLEX

1. Briskly tap tendon of partially stretched muscle 2. Activation of Special Sensory Fibers 3. Sensory impulse travels to spinal cord via a peripheral

nerve 4. Stimulated sensory fiber synapses with anterior horn cell

that innervates the same muscle 5. Impulse crosses neuromuscular junction 6. Muscle contraction

For the reflex to occur, all components of reflex arc must be intact: sensory nerve fibers, spinal cord synapse, motor nerve fibers, neuromuscular junction, and muscle fibers.

PRINCIPLES AND RELATIONSHIPS

Tendons: connects muscles and bones, usu. crossing a joint

Muscle contracts tendon pulls on bone attached structure moves

Striking of tendon by reflex hammer stretch receptors sends impulse to spinal cord via sensory nerves impulse transmitted across a synapse to a lower motor neuron impulse travels down from LMN to target muscle

USING THE REFLEX HAMMER

Pointed end: for striking small areas

Flat end: for larger areas

Larger hammers have weighted heads. Raise approximately 10cm from the target then release to hit tendon with adequate force

Smaller hammers should be swung loosely bet. forefinger and thumb

Striking the area should not elicit pain

REINFORCEMENT

Used if reflexes are symmetrically diminished or absent

Involves isometric contraction of other muscles for up to 10 secs

Increases reflex activity o In testing arm reflexes: ask pt to clench teeth or

squeeze one thigh with the opposite hand.

o JENDRASSIK MANEUVER: In leg reflexes: ask to lock fingers and pull one hand against the other. Tell patient to pull just before you strike the tendon.

1. Have patient relax. Position limbs properly and symmetrically (Neutral Position: not stretched or relaxed)

2. Hold reflex hammer loosely bet. thumb and index finger, so it swing freely in an arc.

3. Relax your wrist, strike briskly using a rapid movement.

4. Note speed, force and amplitude of the reflex response. Grade the response using the scale below.

5. Always compare the response of both sides/extremities.

If having trouble locating tendon ask patient to contract the muscle to which it is attached muscle contracts look and feel for the cord-like tendon (e.g., In identifying the Biceps tendon: ask to flex the forearm to contract the Biceps muscle)

GRADING THE RESPONSE

Bates: 4+ Very brisk, hyperactive, with clonus (rhythmic

oscillations between flexion and extension)

3+ Brisker than average; possibly but not necessarily indicative of disease

2+ Average; normal

1+ Somewhat diminished; low normal

0 No response

Lecture: Sabi ni Doc di raw ito gagamitin, para lang daw aware tayo na meron ding scale na hanggang 5+ 5+ Markedly hyperactive with sustained clonus

4+ Markedly hyperactive with transient clonus

3+ Increased; maybe normal or pathologic

2+ Normal

1+ Decreased but present (hyporeflexia)

0 Absent; no evidence of contraction

Hyperactive reflex (Hyperreflexia): seen in CNS lesions along descending corticospinal tract o Look for associated UMN findings of weakness,

spasticity and (+) Babinski sign

Hypoactive or absent reflexes (hyporeflexia/areflexia): diseases of spinal nerve roots, spinal nerves, plexuses, or peripheral nerves. o Look for associated findings of lower motor unit

disease weakness, atrophy, fasciculations

REFLEX LOCATIONS

Ankle Reflex (S1-2 Sciatic Nerve)

Also Achilles reflex Achilles tendon: taut, discrete, cord-like structure from

heel to muscles of the calf

Primarily S1

1. Best position: Seated, feet dangling over edge of exam table

2. Other positions: Supine, Crossing one leg over the other (figure of 4/frog-type)

3. If unable to locate tendon, ask patient to plantar flex the foot

4. Strike. 5. Calf must be exposed to see muscle contraction

Normal response: Plantar Flexion (Gastrocnemius Contraction)

CALDERON, GARCIA, HARDIN, MANABAT, SOLIS 2 of 5

REFLEX TESTING

2.3-C August 11, 2014

PLM CM Dr. Guzman

If pt is sitting: dorsiflex foot at the ankle

Note speed of relaxation after muscular contraction

Slowed relaxation phase of reflexes in hypothyroidism is oftenly seen and felt in ankle reflex

CLONUS. If reflexes seem hyperactive, test for ankle clonus

1. Support knee in partly flexed position. 2. With your other hand, dorsiflex and plantar flex

the foot a few times while encouraging the patient to relax

3. Sharply dorsiflex the foot and maintain it in dorsiflexion.

4. Look and feel for rhythmic oscillations between dorsiflexion and plantar flexion.

o In most normal people, the ankle does not react to this stimulus. A few clonic beats may be seen and felt, especially when the patient is tense or has exercised

o Clonus may also be elicited at other joints. A sharp downward displacement of the patella, for example, may elicit patellar clonus in the extended knee.

o Sustained clonus indicates central nervous system disease. The ankle plantar flexes and dorsiflexes repetitively and rhythmically.

o When clonus is present, the reflex is graded 4+

Knee/Patellar Reflex (L3-4 Femoral Nerve)

Bates: Knee reflex (L2, L3, L4)

1. Position: Seated feet dangling 2. Identify tendon: thick, broad band of tissue

extending down the knee cap 3. If unable to locate, ask to extend the knee to

contract quadriceps. Or place index finger on top of the knee, then strike the finger to transmit the impulse

4. If in supine, support the back of thigh with hands so the knee is flexed and quads are relaxed

Normal response: Extension of knee (contraction of Quads)

Pt may be sitting or lying down as long as knee is flexed

Hand on pts anterior thigh lets you feel this reflex Two methods when examing supine pt:

o Supporting both knees at once (left picture below)- to assess small differences between knee reflexes by repeatedly testing one reflex and then the other

o Rest supporting arm under the pts leg (Right picture below)

Brachioradialis Reflex (C5-6 Radial Nerve)

Supinator reflex

1. Position: Seated, lower arm resting on pts lap

2. Tendon cant be seen or well palpated. It crossed the radius approx. 10cm proximal to the wrist.

3. Strike. Normal response: Elbow flexion and supination of forearm (palm upward)

Pts hand should rest on abdomen or lap, w/ forearm partly pronated -> strike radius with point or flat edge of reflex hammer, about 1 to 2 inches above the wrist.

Biceps Reflex (C5-6 Musculocutaneous Nerve)

1. Two ways of positioning: pts arm in his/her lap to form an angle slightly >90 at elbow OR support pts arm in yours. Your thumb must be directly over the biceps tendon.

2. If arm is supported, place thumb on the tendon and strike it.

3. If unsupported, place index or middle finger firmly against tendon, then strike.

Normal response: Elbow flexion

Pts arm should be partially flexed at the elbow with palm down

Triceps Reflex (C7-8 Radial Nerve)

Bates: triceps reflex (C6, C7)

1. Two possible positions: form a right angle at the shoulder. Lower arm should be dangling directly downward. OR. Have pt place hands on hips

2. Triceps tendon extends across elbow to the back of the upper arm

3. If arms are on hips: arm will not move, but muscle should shorten vigorously

Normal response: lower arm to extend at elbow and swing away from body

pt may be sitting or supine flex pts arm at elbow, w/ palm toward the body, and pull it slightly across the chest

CALDERON, GARCIA, HARDIN, MANABAT, SOLIS 3 of 5

REFLEX TESTING

2.3-C August 11, 2014

PLM CM Dr. Guzman

OTHER DTRs

Reflex Segment How to Elicit Normal Response

Pectoralis reflex

C5-T1 Have pt elevate arm place fingers of your left hand upon pts shoulders with your thumb extended downwards strike your thumb directly slightly upward toward pts axilla

Muscle contraction seen or felt

Pronator reflex

C6-C7 Grasp pts hand hold it vertically so the wrist is suspended from the medial side strike distal end of radius directly with horizontal blow

Pronation of forearm

Upper abdominal

muscle reflex

T8-T9 Tap muscles directly near their insertions on the costal margins and xiphoid process

Contraction

Mid- abdominal

muscle reflex

T9-T10 Tapping an overlaid finger

Contraction

Lower abdominal

muscle reflex

T11-T12 Tap muscle insertion directly near symphysis pubis

Adductor reflex

L2-L4 Supine, lower limbs slightly abducted Tap directly the Adductor magnus just proximal to its insertion on the medial epicondyle of the femur

Thigh adduction

Hamstring reflex

L4-S2 Supine, hips and knees flexed at

90, thigh rotated slightly outward Place left hand under popliteal fossa to compress medial hamstring

Knee flexion, contraction of medial mass of hamstring

MAKING CLINICAL SENSE OF REFLEXES

Disorders of the Sensory

limb

Prevent or delay transmission of impulse to the spinal cord

causes hyporeflexia or arreflexia

Clinical example: Diabetes-induced peripheral neuropathy

Abnormal LMN

function

hyporeflexia to arreflexia

example: transection of peripheral motor

neuron 2 to trauma reflexes dependent on this nerve will be absent

Complete resection of

UMN

traumatic spinal cord injury

arc receiving input from this nerve

becomes disinhibited hyperreflexia immediately after such injury

hyporeflexia, hyperreflexia develops after several weeks

also seen in death of the cell body of the UMN (located in the brain), as occurs with a stroke affecting motor cortex of brain

Primary disease of NMJ or the

muscle itself

results to loss of reflexes, disease at target organ/muscle precludes movement

Systemic disease states

direct toxicity to a specific limb of the system

poorly controlled diabetes peripheral sensory neuropathy

extremes of thyroid disorder also affects reflexes (mechanism unknown)

Hyperthyroidism hyperreflexia Hypothyroidism hyporeflexia

Detection of an abnormal reflex (hyper/hypo/arreflexia) does not necessarily tell which limb of the system is broken or what might be causing the dysfunction.

Impaired sensory input or abnormal motor nerve function decreased reflexes

Only by considering all of the findings, together with the rate of progression, pattern of distribution (unilateral, bilateral, etc.) and other medical conditions can the clinician make educated diagnostic inferences about the results generated during reflex testing

TROUBLESHOOTING

If unable to elicit reflex: consider the following: o Are you striking the correct place? confirm by

observing and palpating the appropriate region while asking pt to perform an activity that causes the muscle to shorten to make the tendon more apparent

o Make sure that the hammer strike is falling directly on the appropriate tendon if plenty of surrounding soft tissue (dampens force of strike), place a finger firmly on the tendon and use that as target

o Make sure that the muscle is uncovered so that you can see any contraction occasionally, the force of the reflex is not sufficient to move the limb

o Sometimes, the patient is unable to relax inhibits the reflex even if pt is neurologically intact. If this occurs, use REINFORCEMENT.

o Occasionally, it will not be possible to elicit reflexes, even when no neurological disease exists most commonly due to inability to relax. Absence of reflex is of no clinical consequence, assuming that you were thorough in the history taking, used appropriate examination techniques, and identified no evidence of disease

BRAINSTEM REFLEXES

Direct Pupillary Reaction to Light

bright light is shone upon the retina iris constricts

Consensual Pupillary Reaction to Light

stimulation of one retina contralateral constriction of the pupil

Ciliospinal Reflex pinching the skin of the back of neck papillary dilatation

Corneal Reflex touching the cornea blinking of the eyelids

Orbicularis Oculi Reflex retina is exposed to bright light eyelids close

Auditocephalogyric Reflex

loud sound head and eyes turn to source

Jaw Reflex mouth is partially opened and the muscles relaxed + tapping the chin the jaw to close.

CALDERON, GARCIA, HARDIN, MANABAT, SOLIS 4 of 5

REFLEX TESTING

2.3-C August 11, 2014

PLM CM Dr. Guzman

The reflex center is in the midpons

Gag Reflex pharynx is stroked gagging. The reflex center is in the

medulla

SUPERFICIAL REFLEXES/ CUTANEOUS STIMULATION REFLEXES

Have reflex arcs whose receptor organs are in the skin rather than in the muscle fibers

Adequate stimulus is stroking, scratching, or touching

These reflexes are lost in disease of the pyramidal tract

Superficial Reflexes

Reflex Segment Procedure &

Expected Response

Upper abdominal skin

reflex

T5-T8 Bates: T8-T10

With patient supine, stroke the

skin with blunt handle towards

the midline

Ipsilateral contraction of

muscles or umbilical deviation

towards the stimulated side

Mid abdominal skin reflex

T9-T11

Lower abdominal skin

reflex

T11-T12 Bates: T10-T12

Cremasteric reflex

L1-L2

Stroke the inner aspect of the thigh

from the pubis distad

Prompt elevation of the testis on the

ipsilateral side

Plantar reflex L4-S2

Bates: L5, S1

Stroke the sole near its lateral

aspect from the heel towards toes

Plantar flexion of

the toes

Superficial anal reflex

L1-L2 Bates: S2-S4

Stroke the skin of the perianal region

External anal

sphincter contracts

Glabellar reflex Corticopontine

Lightly tap the forehead between the eyebrows with

the fingers

(ABNORMAL) Persistent

blepharospasm and closing of the

eyes

Snout reflex Corticopontine

Tap the nose

(ABNORMAL) Excessive

grimace of the face

Sucking reflex Frontal cortex

Stroke the lip with the finger or a

tongue depressor

(ABNORMAL) Lips pout and make sucking movements

*Present in infants

but disappears after weaning; reappears in

diffuse lesions of

the frontal lobe and commonly

noted in dementias

Chewing reflex Frontotemporal

cortex

Place a tongue depressor in the

mouth

(ABNORMAL) Chewing

movement of the teeth and jaw

*Seen in

dementia, general paresis, and

anoxic encephalopathy

ABNORMAL REFLEXES IN PYRAMIDAL TRACT DISEASE

BABINSKI SIGN

A.k.a hallucal dorsiflexion reflex

Test used to assess upper motor neuron dysfunction

1. The patient may either sit or lie supine. 2. Start at the lateral aspect of the foot, near the heel.

Apply steady pressure with the end of the hammer as you move up towards the ball (area of the metatarsal heads) of the foot.

3. When you reach the ball of the foot, move medially, stroking across this area.

4. Test the other foot.

Normal response: the first movement of the great toe should be downwards (i.e., plantar flexion) Upper Motor injury: (e.g., spinal cord injury or stroke): great toe will dorsiflex and the remainder of the other toes will fan out

Some patients find this test to be particularly noxious/uncomfortable. Tell them what you are going to do and why. If its unlikely to contribute important information (e.g., screening exam of the normal patient) and they are quite averse, simply skip it.

Newborns normally have a positive Babinski which usually goes away after about 6 months

Sometimes you will be unable to generate any response, even in the absence of disease. Responses must, therefore, be interpreted in the context of the rest of the exam.

For reasons of semantics, Babinski is not recorded as + or -

Withdrawal of the entire foot (due to unpleasant stimulation), is not interpreted as a positive response

GRASP REFLEX

Stroke the patients palm so he/she grasps your index finger

If present, the patient cannot release the fingers; lesions of the premotor cortex

HOFFMANS SIGN

Have patient present pronated hand with fingers extended and relaxed

With your thumb, press his/her fingernails to flex the terminal digit and stretch the flexor

CALDERON, GARCIA, HARDIN, MANABAT, SOLIS 5 of 5

REFLEX TESTING

2.3-C August 11, 2014

PLM CM Dr. Guzman

Abnormal response: flexion and adduction of thumb

MAYERS REFLEX

Have patient present his/her supinated hand with thumb relaxed and abducted

Grasp the ring finger and firmly flex the metacarpophalangeal joint

Normal response: adduction and apposition of the thumb

PALM-CHIN REFLEX

Aka Radovicis sign Vigorous scratching or pricking of the thenar eminence

causes ipsilateral contraction of the muscles of the chin

SPECIAL TECHNIQUE: MENINGEAL SIGNS

Testing for these signs is important if you suspect meningeal inflammation from meningitis or subarachnoid hemorrhage

Nuchal rigidity

Patient cannot place the chin upon the chest

Passive flexion of the neck is limited by involuntary muscle

spasm

Spinal rigidity Movements of the spine are limited by spasms of erector

spinae

Kernigs sign

With patient supine, passively flex the hip to 90 while the knee is flexed at

about 90

Attempts to extend the knee produce pain in the

hamstring and resistance

Bates: pain and increased resistance to extending the knee are a positive Kernigs

sign

Brudzinskis sign

With patient supine and the limbs extended, passively

flex the neck

Produces involuntary flexion of the hips

Bates: flexion of both the

hips and knees is a positive Brudzinkis sign

^Parang hindi naman lahat ito Reflex? :/ Pero dito siya included sa lecture, so

MAKING SENSE OF NEUROLOGICAL FINDINGS

While compiling information generated from the motor and sensory examination, the clinician tries to identify patterns of dysfunction the will allow him/her to determine the location of the lesion(s). What follows is one way of making clinical sense of neurological findings.

Is there evidence of motor dysfunction (e.g., weakness, spasticity, tremor)?

o If so, does the pattern follow an upper motor neuron or lower motor neuron pattern?

o If its consistent with a UMN process (e.g., weakness with spasticity), does this appear to occur at the level of the spinal cord or the brain?

- Complete cord lesions: affect both sides of the body

- Brain level problems: affect one side

- It is, of course, possible for a lesion to affect only one part of the cord, leading to findings that lateralize to one side.

o Is it consistent with a LMN process (e.g., weakness with flaccidity)? Does the weakness follow a specific distribution (e.g., following a spinal nerve root or peripheral nerve distribution)? Bilateral? Distal?

Do the findings on reflex examination support a UMN or LMN process (e.g., hyperreflexic in UMN disorders and hyporeflexic in LMN disorders)?

Do the findings on Babinski testing (assuming the symptoms involve the lower extremities) support the presence of a UMN lesion?

Is there impaired sensation? Some disorders, for example, affect only the upper or lower motor pathways, sparing sensation.

Which aspects of sensation are impaired? Are all of the ascending pathways (e.g., spinothalamic and dorsal columns) affected equally, as might occur with diffuse/systemic disease?

Does the loss in sensation follow a pattern suggestive of dysfunction at a specific anatomic level? For example, is it at the level of a spinal nerve root? Or more distally, as would occur with a peripheral nerve problem?

Does the distribution of the sensory deficit correlate with the correct motor deficit, assuming one is present? Radial nerve compression, for example, would lead to characteristic motor and sensory findings.

SUMMARY OF SPINAL LEVELS

This is just Bates based. Please refer to preceding pages for those from the lecture/ those not found here.

Deep Tendon Reflex Spinal Levels

Biceps reflex C5-C6

Supinator/Brachioradialis

Reflex

C5-C6

Triceps Reflex C6-C7

Knee Reflex L2-L4

Ankle Reflex Primarily S1

Cutaneous Stimulation

Reflex

Spinal Levels

Abdomen above umbilicus T8-T10

Abdomen below umbilicus T10-T12

Plantar Response L5-S1

Anal Reflex S2-S4

o