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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