DEMONSTRATION- reflex.ppt

reflex

1. DEMONSTRATION
OBJECT –
ELICITATION OF SUPERFICIAL
REFLEXES
REFLEXES
By-Nikita Jain
(Tutor) Physiology

2. Reflex–
Itisanrapid,predictable,unconsciousand
involuntaryresponse(i.e.contractionofa
muscleorsecretionofglands)toaspecific
stimulus.

3. Diagram showing the pathway of reflex arc with its different components
Stimulus
1-Receptor
In skin
stimulated
2-sensory
neuron
3-integration
center
interneuron
4 –Motor
neuron
5–Effector

4. APPARATUS–
Patellar Hammer, Examination couch, torch, cotton etc.

5. Parts of knee hammer
1-Itconsistofalongmetallichandle
Atoneendonwhichatriangularshapedsoftrubber
pieceisattached.
Thisrubberpieceisusedtogiveasharpblowtomuscle
tendon,inordertogetsuddenstretchingofitsmuscle.
Onotherendofhandleisalsoprovidedwithbrushof
nylonhairsandapointerfortestingsensorycomponents
ofneurologicalexamination.

6. 2-Therubberpiecehastwoend–
-Thebroaderend
-Pointedornarrowend.
Thebroaderendisusedwhenthemusclebellyis
broaderandthin(liketendonoftricepsmuscle),
whilethepointedendisusedwhenthetendonis
stoutandnarrow(asofbicepsmuscletendon)

7. Thespecificnerverootsthatcomprisethearcsarelistedforeach
ofthemajorreflexesdescribedbelow.
CLINICALLY TESTED REFLEXES -
A-Superficial reflexes B-Deep reflexes
1-Planter reflex,
2-Abdominal reflex
1-Conjunctival reflex
2-Corneal reflex
3-Pupillaryreflex
1-Knee Jerk
(Or Patellar)
Or Qudericeps
Femoris Jerk
2-Ankle Jerk
(Or
Gasterocnemuis
Jerk)-
3-Triceps Jerk4-BicepsJerk
5-Brachioradialis jerk
6-Jaw Jerk

8. Pre-requisites-
1-makesurethatthesubjectiswarmandcomfortable
2-explaintheproceduretothesubjectbeforeeliciting
thereflexinordertomakehimrelax,reassureand
decreaseanxietyandapprehensionassociatedwiththe
test.
3-subjectattentionshouldbedivertedfromthetestto
obtainbetterresponsetothestimulusapplied.

9. A-Superficialreflexes-
Ifastimulusisappliedonsuperficialstructuresofthebody
likeskinormucousmembrane,itresultsincontractionof
underlyingmuscles.Thisgroupofreflexesispolysynaptic.
Following are superficial reflexes -
Reflexes based on cranial nerves-
1-Conjunctival reflex
2-Corneal reflex
3-Ciliospinal reflex
4-Pupillary reflex
Reflexes based on spinal nerves
1-Planter reflex, 2-Abdominal reflex,
Cremestric, Bulbocavernosus, Anal, Scapular reflex

10. CORNEAL REFLEX
•Take a wisp of cotton
and ask the subject to
look to one side and
bring the wisp just to
touch the cornea.
•Obsevation-Closure of
the lids.
•Afferent nerve-Vth
•Efferent nerve-VIIth

11. CONJUCTIVAL REFLEX
•Touch the conjuctiva
with a cotton wool
swab.
•Observation-Closure of
the lids.
•Afferent nerve-Vth
•Efferent nerve-VIIth

12. CILIOSPINAL REFLEX
•Pinch the skin of
neck.
•Observation-
Dilatation of pupil.

13. 1-PLANTERREFLEX-toelicititthesoleshouldbewarmandclean,withleg
completelyrelaxed.
Procedure–gentlyscratchtheouteredgeofthefootwithabluntobject(say
keyorbluntendofkneehammerhandle)fromheeltowardsthelittletoe
andthenmediallyalongthebaseoftheothertoesupto2
nd
toe.
Babinski Response Present

15. Interpretation:
Inthenormalpatient,thefirstmovementofthegreattoe
shouldbedownwards(i.e.plantarflexion).Ifthereisanupper
motorneuroninjury(e.g.spinalcordinjury,stroke),thenthe
greattoewilldorsiflexandtheremainderoftheothertoeswill
fanout.
NormalResponse:
PlantarFlexionOfTheFootAndToes.
Babinski sign negative
AbnormalResponse:
Babinski sign positive-
Dorsiflexion Of Great Toe and
Fanning Of Other Toes and
Dorsiflexion Of Ankle

16. LevelofSpinalcordinvovles:
L5,S1,S2afferentandefferentnerveistibialnerve
Importance-
Theplantarreflex(theBabinskiresponsefirstdescribedby
Babinskiin1896)isimportantinidentifyingaUMNlesion;
Examples–
normallyininfantsbelow1-2yearsanddeepsleep
PathologicallyinUppermotorneuronlesion,spinalcord
tumour,comaduetoanycauseetc.

17. 2-ABDOMINALREFLEX-
SegmentalInnervation:T7-12
PROCEDURE-Toelicittheabdominalreflex,patientliesrelaxedand
supine,withtheabdomenuncovered.Akeyorthereverseendofthe
tendonhammerisdraggedquicklyandlightlyacrosstheabdominalskin
lightlyinamedialdirectionacrosstheupperandlowerquadrantsofthe
abdomenparalleltocoastalmarginandinguinalligament.
Fig:-abdominal reflex

19. NORMAL RESPONSE-Arippleofcontractionofthe
underlyingabdominalmusculaturefollowsthestimulus.
Abdominalreflexesaredifficulttoelicitinobeseormultiparous
womenandinanxiouspatients.
AbnormalResponse:areabsentinUMNlesionsabovetheir
spinallevel,aswellasinlesionsofthelocalsegmentalthoracic
rootorthespinalcord.

20. Thank you

21. DEEP(ORTENDON)REFLEXES-
Atendonreflexistheinvoluntarycontractionofamusclein
responsetostretch.
Itismediatedbyareflexarcconsistingofanafferent
(sensory)andanefferent(motor)neuronwithonesynapse
between:thatis,amonosynapticreflex.
Musclestretchactivatesthemusclespindles,whichsenda
burstofafferentsignalsthatinturnleadtodirectefferent
impulses,causingmusclecontraction.
Thesestretchreflexarcsareservedbyaparticularspinalcord
segmentwhichismodifiedbytheinfluenceofdescending
uppermotorneurons.

22. Followingdeepreflexeswillbeexaminedintheclinicallab-
1-KNEEJERK(ORPATELLAR)ORQUDERICEPSFEMORISJERK
Procedure-
Insupineposition–theexaminer'shandispassedunder
thekneetobetestedandplacedontheoppositekneeor
thetestkneerestsonthedorsumoftheexaminerswrist.
Strikethepatellartendonmidwaybetweenitsoriginand
insertion.
Insittingposition-Alternately,itcanbealsomoreeasily
elicitedwiththesubjectssittingup,theleghangingfreely
orcrossedlegsontheedgeofbed.

23. Fig: sitting position
Fig: supine position
Response-Abriefcontractionof
thequadricepsfemorismuscle
resultsinextensionoftheknee.
Afferentandefferentpathsare
femoralnerve,levelofspinal
cordinvolves–L2,3,4
Clinicalsignificance-pendullar
inacutecerebellardiseaseand
presentonthesideoflesion.In
hypothyroidtheyareweek
whileinhyperthejerksare
brisk.

26. 2-ANKLEJERK(orgasterocnemuisjerk)-
PROCEDURE-
Insupineposition-subjectliesinsupine,withsemiflexedkneeandexternally
rotatedhip.Thenwithonehandtheexaminerslightlydorsiflexedthefootso
astostretchtheAchillestendonandwithotherhand,tendonisstruckonits
posteriorsurface.
Insittingposition-Anothermethodistoaskthesubjecttokneeloverchairso
thatthehefacesthebackofthechairandhisankleslie,overitsedge.
RESPONSE-planterflexionofthefootduetocontractionof
thecalfmuscle.
Afferentandefferentnerve–tibalnerveandcentreissacral
1,2segments.

28. 3-TRICEPS JERK-
PROCEDURE-
Instanding/sitting-thearmisflexedtorightangleandis
supportedontheexaminer’sarm.thetricepstendonisthen
struckjustproximaltothepointoftheelbowwithbroaderendof
patellarhammer.
Insupineposition-flextheelbowandallowittorestacrossthe
subject’chest.Tapthetendonwithhammer.
RESPONSE-
Contractionoftricepsmusclewithextensionatelbow.
Afferentandefferntpath-radialnerve;centreisC-6,7

30. 4-BICEPSJERK–
PROCEDURE-
Instandingposition-Thesubject’sarmisflexedtoarightangleand
theforearmsemipronatedandsupportedontheexaminer’shand.
-Theexaminerthenplaceshithumbonthebicepstendonand
strikesitwiththenarrowendofhammer.
Insupineposition-Thesubject’sarmisflexedtoarightangleand
theforearmsemipronated,restoverthechestofthesubject.
-Theexaminerthenplaceshithumbonthebicepstendonand
strikesitwiththenarrowendofhammer.

31. Biceps Reflex Testing, armsupported
Biceps Reflex Testing, in supine
position

32. RESPONSE-
Contractionofbicepsmusclewithflexionatelbowandslightly
pronationoftheforearminstandingposition.
Ifthepatientisinsupinepositionthenbicepsmuscle
contractionisobserved.
Afferentandefferentpath-musculocutaneousnerve;centreis
C-5,6.

33. 5-SUPINATORJERKORBRANCIORADIALISJERK
Procedure–sameasthebicepsprocedureforsupine
position.tapthebrachioradialistendonuponstyloidprocess
ofradius.
ThetendonoftheBrachioradialismusclecannotbeseenor
wellpalpated,whichmakesthisreflexabittrickytoelicit.The
tendoncrossestheradius(thumbsideofthelowerarm)
approximately10cmproximaltothewrist.
Response-Contractionofbrachioradialismusclewith
supinationofelbow.
Afferentandefferentpath-radialnerve;centreisC-5,6.

35. 6-JAWJERK–
Procedure–Askthesubjecttoopenmouthbutnottoowidely.
Placeonefingerfirmlyonchinandtapsuddenlywiththeother
hand(likepercussion).
Response-contractionofmassatermuscleresultinginclosingof
jaw.Sometimethisjerkcannotelicitinthehealthysubjects.

36. Note-
ifunabletoelicitanytypeofreflex
thenapplyreinforcement;Jenderassik’s
manoeuvre.
Inthissubjectisaskedtoperform
somemusculareffort,suchasclenching
theteethorlockingthefingersofthe
handsashardaspossibleandthentrying
topullthemapartwhiletheexaminer
strikesthetendonfoeexamplepatellar
tendon.
Itresultsinincreasingexcitabilityofthe
anteriorhorncellsforimpulsesandalso
increasesofgammamotorneuron
activitywhichincreasethesensitivityof
thespindlecellstostrech.

37. ClinicalSenseofReflexes:
Normalreflexesrequirethateveryaspectofthesystem
functionnormally.Breakdownscausespecificpatternsof
dysfunction.Theseareinterpretedasfollows:
•Disordersinthesensorylimbwillpreventordelaythe
transmissionoftheimpulsetothespinalcord.Thiscausesthe
resultingreflextobediminishedorcompletelyabsent.Diabetes
inducedperipheralneuropathy(themostcommonsensory
neuropathyseenindevelopedcountries),forexample,isa
relativelycommonreasonforlossofreflexes.
Abnormallowermotorneuron(LMN)functionwillresultin
decreasedorabsentreflexes.If,forexample,aperipheralmotor
neuronistransectedasaresultoftrauma,thereflexdependent
onthisnervewillbeabsent

38. Iftheuppermotorneuron(UMN)iscompletelytransected,as
mightoccurintraumaticspinalcordinjury,thearcreceiving
inputfromthisnervebecomesdisinhibited,resultingin
hyperactivereflexes.
Note,immediatelyfollowingsuchaninjury,thereflexesare
actuallydiminished,withhyper-reflexiadevelopingseveral
weekslater.
Asimilarpatternisseenwiththedeathofthecellbodyofthe
UMN(locatedinthebrain),asoccurswithastrokeaffectingthe
motorcortexofthebrain.
Primarydiseaseoftheneuro-muscularjunctionorthemuscle
itselfwillresultinalossofreflexes,asdiseaseatthetargetorgan
(i.e.themuscle)precludesmovement.

39. •Anumberofsystemicdiseasestatescanaffectreflexes.
•Somehavetheirimpactthroughdirecttoxicitytoaspecificlimbofthesystem.
•Poorlycontrolleddiabetes,asdescribedabove,canresultinaperipheralsensory
neuropathy.
•Extremesofthyroiddisordercanalsoaffectreflexes,thoughtheprecise
mechanismsthroughwhichthisoccursarenotclear.Hyperthyroidisimis
associatedwithhyperreflexia,andhypothyroidismwithhyporeflexia.
•Detectionofabnormalreflexes(eitherincreasedordecreased)doesnot
necessarilytellyouwhichlimbofthesystemisbroken,norwhatmightbecausing
thedysfunction.
•Decreasedreflexescouldbeduetoimpairedsensoryinputorabnormalmotor
nervefunction.
•Onlybyconsideringallofthefindings,togetherwiththeirrateofprogression,
patternofdistribution(bilateralvunilateral,etc.)andothermedicalconditionscan
theclinicianmakeeducateddiagnosticinferencesabouttheresultsgenerated
duringreflextesting.

40. Note-thetendonreflexarediminisedorabsent,onbothoronesides,in
lesioninvolvingtheafferntpathways(e.gtabesdoralis),theanteriorhorn
cells(poliomyelitis),ortheefferentpathways,andalsoinspinalshock.
Tendonreflexexaggeratedinfollowingconditions-
-UMLabovetheanteriorhorncells
-Anxiety
--hyperexcitibilityofnervoussystem,asinhyperthyroidismandtetanus
Observation and result-
Tabulated your result as under:
REFLEXES RIGHT SIDE LEFT SIDE REMARK/
GRADING