Limb Weakness: Radiculopathies and Compressive Disorders · Myotome Definition: Muscles innervated by a single nerve root = myotome Nerve ... • Sensory parethesiaor hypoesthesia

LimbWeakness:RadiculopathiesandCompressiveDisorders

SpotthebraincellDr.TheoMobachPGY-4Neurology

[email protected]

Image:Felten,Shetty.Netter’sAtlasofNeuroscience.2nd Edition.

Objectives• Basicneuroanatomyofperipheralnervoussystem

• Physicalexam:motorandsensorycomponents

• Commonentrapmentneuropathies– MedianNeuropathyattheWrist– UlnarNeuropathyattheElbow– FibularNeuropathy

• Radiculopathies

UMNvs LMNUpperMotorNeuron Lower MotorNeuron

• Spasticity• Hyperreflexia• Pyramidal patternofweakness

• Babinskisign

• Atrophy• Hypotonia• Decreasedorabsentreflexes

• Fasciculation's

MotorUnit

Motorneuron SkeletalMuscleFibers

Oftenseveralmotorunitsworktogethertocoordinatecontractionofasinglemuscle

SpinalRoots

Image:Olson,Pawlina.StudentAtlasofAnatomy.2ndEdition


Dermatome

Definition:

Asensoryregionofskininnervatedbyanerveroot=dermatome


SensoryInnervationCutaneous

NerveBranches

Images:Felten,Shetty.Netter’sAtlasofNeuroscience.2nd Edition.

Myotome

Definition:

Musclesinnervatedbyasinglenerveroot=myotome

NerveRoot

Muscle PeripheralNerve

C5 DeltoidsInfraspinatusBiceps

AxillaryN.SuprascapularN.Musculocutaneous

C6 BicepsWristextensors (ECR)

MusculocutaneousRadialN.

C7 TricepsFingerextensors(EDC)

RadialN.PIN(RadialN.)

C8 Extensor indicis proprius (EIP)Medianinnervatedintrinsichandmuscles(LOAF)

PIN(RadialN.)Median

L4 Quadriceps Femoral

L5 FootdorsiflexionFootinversionFoot eversionHip abduction

Fibular N.FibularN.Tibial N.Gluteal N.

S1 Foot plantarflexion,Hipextension

Tibial N.GlutealN.

Recall

• Writedown2muscleforeachofthefollowingmyotomes,themusclesMUSTbefromdifferentperipheralnerves:– C6– C8– L5– S1

AnswerNerveRoot

Muscle PeripheralNerve

C6 BicepsWristextensors (ECR)

MusculocutaneousRadialN.

C8 Extensor indicis proprius (EIP)Medianinnervatedintrinsichandmuscles(LOAF)

PIN(RadialN.)Median

L5 FootdorsiflexionFootinversionFoot eversionHip abduction

Fibular N.FibularN.Tibial N.Gluteal N.

S1 Foot plantarflexion,Hipextension

Tibial N.GlutealN.

PeripheralNerve


MuscleFibers

Pneumonic:Type1:1slowfatredoxType2:2fastskinnywhitebreasts

Attribute Type1Fiber Type2Fiber

Grosscolour Dark Light

Oxidativeenzymes High Low

Lipid High Low

Mitochondria High Low

Glycogen Low High

Function Sustainedcontraction Briefcontraction

TwitchSpeed Slow Fast

Metabolism Aerobic Anaerobic

Fatigue Resistant Sensitive

MotorExam• Bulk

– Observeforfasciculation's– Assessforatrophy

• Tone– Determinerelationshipwith

velocity(rigidityvs spasticity)

• Strength– MRCscale

• Reflexes– Gradeusinga0-4scale– Babinski,clonus

MRCSCALE0 No movement

1 Flicker2-

2

NotfullROM

Gravityeliminated

3-

3

Not fullROM

AgainstGravity

4-44+

MildresistanceMod.resistanceGoodresistance

5-

5

Questionably full

FullStrength

MotorExamPearls

• Alwaysexplainbeforetestingstrength

• Adjuststrengthtestingbasedonpatient

• Rememberneckflexionandextension– Usefulcorrelateforrespiratoryweakness

• Screenforbulbar,facial,andeyeweakness

MotorExamPearls• Whenexaminingsmallmusclesofthehand,uselikeagainstlike,matchingyourcorrespondingmuscle

• Musclearemostpowerfulwhenmaximallyshortened

• Forunilateralweaknessusethecontralateralsideasacontrol

• Alwaysassessthelowerextremitiesevenwhensymptomsareonlyupperextremity.MotororsensorychangesplusUEradiculopathycouldindicatemyelopathyintheC-spine

SensoryExamSpinothalamic• Standardizedmethodofstarting

withC2andgoingdownthelateralaspectofthearmandupthemedialaspectwithpinprick,thenlighttouch.

DorsalColumn• Vibrationrarelyaffectedinthe

hands,screenwithfeet• Jointpositionsense

Corticalsensation:considerintheappropriatesetting


Non-neurologicexamination

• NeckROMandSpurling• Jointexamasindicated(shoulder)• Medialorlateralepicondylitis• PIP/DIPs/CMPsforarthritis• Pressurepointsformyofascialpain

Non-organicweakness• Effortiserraticandvariable

• Iftheexaminerdecreasesresistancethepatientwithnon-organicweaknessstopstrying

• Non-organicflaccidlimbmayfallslowlywhendroppedtoavoidinjury

• Patientwithnon-organicweaknessmaynotbecalmorindifferenttowardstheweakness

• Hoover’ssign

MedianNervevsC6Radiculopathy

Preston,Shupiro.ElectromyographyandNeuromuscularDisorders.3rd Edition

MedianNerveAnatomy

Image:Preston,Shupiro.ElectromyographyandNeuromuscularDisorders.3rd Edition

MedianinnervatedmusclesintheHand

LOAF• Lumbricals 1and2• Opponens pollicus• Abductorpollicus brevis• Flexorpollicus brevis

MedianNeuropathySensory


MedianNeuropathyattheWristClinical• Common:1-5%ofthepopulation• Women>men• Dominanthand>non-dominant

• Sensory paresthesiafirst3.5digits– Nocturnalparesthesiacommon

• Pain:wrist,mayradiateintotheforearmorarm,rarelyshoulder

• Provokingfactors:wristflexionorextension,activitiesrequiringprolongedhandgrip

• Relievingfactors:shakingtheirhand,wringingitout,warmwater

• Motor:functionallimitationtoMNWisuncommon

Table:Preston,Shupiro.ElectromyographyandNeuromuscularDisorders.3rd Edition

MedianNeuropathyattheWrist

ProvocativeTesting• Tinel’s Test(50%/77%)• Phalen’s Test(68%/73%)• Manualcarpalcompression(64%/83%)

• Handelevationtest(similarsensitivityandspecificitytotinel andphalen)


MNWDdxPeripheralNervousSystem• Proximalmedianneuropathy• Medialcordorlowertrunklesion• C6radiculopathy

CentralNervousSystem• Stroke:lacunar,corticalhand• Myelopathy• Demyelinatinglesion


MNWTreatment• Conservative– NocturnalCarpelTunnelSplints– Avoidaggravatingactivities– ScreenforDMandHypothyroidism

• CarpelTunnelSurgicalRelease

• Othertherapies– Hydrodissection (mild-moderateseverityCTS)

– Steroidinjection

Image:https://commons.wikimedia.org/wiki/File:Carpal_tunnel_splint.jpg

Image:https://commons.wikimedia.org/wiki/File:Carpal_Tunnel_Syndrome.png

CervicalRadiculopathyClinical• Painandparesthesia inthedistributionofanerveroot• Associatedparaspinal musclespasmtypicallylimits

movementsthatexacerbatesymptoms

Examination• Sensoryparethesia orhypoesthesiainvolvingadermatome• Weaknessinvolvinganerverootmyotome• Reflexesmaybedepressed• Spurling Test• Horner’ssyndrome

CervicalRadiculopathyEtiology• Discogenic• Spondylosis• Masslesionssuchasbone

mets orepiduralabscess

Lesscommonetiologies• Leptomeningeal

carcinomatosis• Infection(HSV,VZV,CMV)• Vasculitis• GBS

Image:https://commons.wikimedia.org/wiki/File:728_Herniated_Disk.jpg

CervicalRadiculopathyTreatment• Conservative

– Physicaltherapy• ROM,stretching,strengthening

– Oralanalgesia:• simpleanalgesia+/- musclerelaxant

– Shorttermsoftcollar– Oralsteroids

• Shortcourseifpainissevere– Avoidanceofprovocativeactivities

• Epiduralsteroidinjections• SurgeryIndication

– Myelopathy– Progressiveweakness– Unremittingradicularpaindespite6-8weeksofconservativetherapy

MNWvs C6MNW C6radiculopathy

History Noctornal paresthesia NeckpainRadicularpainSx worsewithneckmotion

Sensory PalmarsparingInvolvesdigit3(C7)

Sensorychanges extendpastthewrist

Motor Lumbricles 1&2, FPB,APB,OP

Biceps, brachialis,brachioradialis,wristextension

Reflexes None Biceps,brachioradialis

SpecialTests CarpeltunnelcompressiontestPhalen’sTinel’s

Spurling’sHorner’s

UlnarNervevsC8Radiculopathy


UlnarNerveAnatomy• DerivedfromC8/T1

Nerveroots

• Nobranchesinthearm

• Ulnargroove:formedbetweenmedialepicondyleandolecrenon

• TravelsthroughthewristviaGuyon’s canal


• Etiology:– CompressionorStretch– Trauma

• Clinical– Motorsymptomsarecommon:lossofdexterityanddecreasedhandgrandpinchstrength– Atrophyofthenar andhypothenar eminence– Sensory:paresthesia orhypoesthesiamedialaspectofthehand– Reflexes:normal

• DifferentialDiagnosis– Medialcord,lowertrunkorC8/T1lesion

• Treatment:– Conservative:

• avoidcompressionandstretch,• helbow pad

– Surgery

UlnarNeuropathyattheElbow


UlnarNeuropathyExam

BenedictssignFroment sign

Wartenberg sign


Ulnarneuropathyexam


Ulnarvs C8/T1Ulnar C8/T1radiculopathy

History Compressionorstretchmechanismof injury

NeckpainRadicularpainSx worsewithneckmotion

Sensory Medial dorsalandvolaraspectofthehand


Motor ADM,dorsal andpalmarinterossei,lumbricles 3&4,adductorpollicus,

Extensor indicespropriusMedianintrinsichandmuscles

Reflexes None FingerFlexor

SpecialTests Tinel’s Spurling’sHorner’s

FingerFlexorReflex=C8/T1

Image:http://www.sciencedirect.com/topics/page/Hyperreflexia

Image:Preston,Shupiro.ElectromyographyandNeuromuscularDisorders.3rd EditionImage:http://www.aafp.org/afp/2013/0415/p568.html

FibularNervevsL5Radiculopathy


FibularNerveAnatomy


Fibularneuropathy• FibularnerveispredominantlyL5(L4-S1)

• Clinical– Weaknessofankleandtoedorsifexion– Presentswithfootdrop,slapfoot,tripping– Sensorychangesovermidandlowerlateral

calfanddorsumofthefoot

• Etiology– Trauma– Forciblestretchinjury– Compressionfromprolonged

immobilization– Positions:Legcrossing,squating– Tightfittingboots(skiboots)

Image:https://bluestarr.wordpress.com/2011/12/28/230/

Fibularvs L5Fibular L5Radiculopathy

History Mechanismoftrauma,stretchorcompressionatthefibularhead

BackpainRadicularpainBladderorbowelsymptoms

Sensory Midandlowerlateralcalfanddorsumofthefoot

L5 dermatomeandsymptomsmayextendabovetheknee

Motor Dorsiflexion andeversion Hip abductionAnkleinversion

Reflexes None None

SpecialTests Tinel’s StraightlegraiseCrossedlegraise

Radiculopathies


Radiculopathies• Sensoryormotordysfunctiondue

topathologyofanerveroot

• Clinical– Pain– Weaknesswithinamyotome– Sensorychangeswithina

dermatome– Antecedentevents:trauma,heavy

lifting,physicalexertion• Onset

– Acute:suggestsdiscogenic etiology(youngerage,20%)

– Subacute/chronic:suggestsspondylosis (olderage,70%)


RadiculopathiesCommonCausesofRadiculopathy– Discherniation– Osteophytes– Spinalstenosis– Trauma– Diabetes– EpiduralAbscess– EpiduralMetastases– NerveSheathTumor– Guillain-BarreSyndrome– HerpesZoster– LymeDisease– Cytomegalovirus– IdiopathicNeuritis


Radiculopathies

CommonLocations– C6andC7mostcommon

cervicalradiculopathies

– L5andS1mostcommonlumbosacralradiculopathies

– 2/3ofdiscogenicradiculopathiesoccurinthelumbosacralregion


RadiculopathiesredFlags

• Signs/symptomstosuggestinflammatory,neoplasticorinfectiousetiology– Age>50– Historyofcancer– Fever– Unexplainedweightloss– Immunosuppression– Painthatdoesn’timproveintherecumbentposition– Symptomsthatdon’timprove1monthafterconservativetherapy

LumbosacralRadiculopathyTreatment• Conservative

– Physicaltherapy• ROM,stretching,strengthening

– Oralanalgesia:• simpleanalgesia• Musclerelaxants• Opioidanalgesia(shortterm)

– Oralsteroids• Shortcourseifpainissevere(5-7days)

– Avoidanceofprovocativeactivities

• Epiduralsteroidinjections– Moderateshorttermbenefit

• SurgeryIndication– Persistentorprogressiveneurologicdeficits– Unremittingradicularpaindespite6-8weeksof

conservativetherapy– Benefitsofsurgeryseemtodecreaseovertime

comparedtonon-surgicalgroups


AlternativeEtiologies

• Whiplashinjury• Rheumatoidarthritisofthespine• Fibromyalgia/myofascial syndrome• Polymyalgiarhuematica• Tendonitis,bursitis,arthritis

Review

QuizCases


Quiz


QuizCase1:

48yearoldmarriedfemaleworksfulltimeasaadministrativeassistantpresentswith3monthsofnumbnessinD4&5anddecreasedgripstrength.

1. MainDdx:list4anatomicallocations2. Specificexamtests3. Treatment

AnswertoCase1Ddx:• Ulnarneuropathy• medialcordlesion• lowertrunklesion• C8radiculopathyExamination• Sensory:

– istheresensorylossonthedorsumofthehand(UNE)– doesthesensorylossextendpastthewrist(C8radiculopathy)

• Motor:– isthereweaknessofulnarinnervatedhandmuscles(FLOAD)?– IsthereweaknessofC8musclesbyotherperipheralnerves(EIP

=radial,medianintrinsichandmuscles)• SpecialTests:

– Handpositions(benedicts,wartenberg,

QuizCase• 64yo malewith4monthhistoryofweaknessandwastingofhisrighthand.Noassociatedpain.Recentlynotedsomelefthandweakness.

• Examshowsatrophyrighthand(thenar,hypothenar,andflexorcompartment),fasciculations,reflexes3+,bilateralhoffmans.Normalsensation.

Muscle Right Left

SA 5 5

EF 5 5

EE 5 5

WF 4+ 5

WE 4+ 5

FDI 4 4+

ADM 4 4+

ABP 4 4+

FDS 4 4+

FDP 2-5 4 4+

AnswerCase2

ThepatternofprogressiveweaknessandatrophywithbothUMNandLMNfeaturesisconcerningforamotorneuronlocalization.

UMN:• IncreasedreflexesLMN:• Atrophy,fasciculations,weakness

Image:http://slideplayer.com/slide/2465604/

CaseQuiz357yo Mwithlowbackpainfor20years.Trippedoveradoorledgeanddevelopedsuddenincreaseinright-sidedlowbackpainradiatingdownhislegintotherightbigtoe.

Exam:• Motor:

– 3/5rightextensorhallicus longusandtibialisanterior– 4+/5rightinvertorsandevertors

• Sensory– Decreasedpinprickoverrightanterolateralcalfanddorsumofthefoot

• Positiverightstraightlegraise

Whereisthemostlikelylocalization?Listthefeaturesonhistoryandexamtosupportyourlocalization?Howwouldyoumanagethispatient?

AnswerQuiz3

Whereisthemostlikelylocalization?• RightL5nerveroot

Listthefeaturesonhistoryandexamtosupportyourlocalization?

• History:traumaticincitingevent,priorhistoryoflowbackpain,radicularsymptoms

• Exam:L5weaknessoutsideofthefibularnerve(namelyinnvertors withweaknessoftibalis posteriorinnervatedbythetibial nerve.

Howwouldyoumanagethispatient?• Conservativetherapy:analgesia,physicaltherapy,avoidprovocative• Surgicalconsiderationifsymptomspersistorprogressorpainisrefractory

QuizCase4

30yo Mwith4weekstinglingandpaininhisfirstandsecondfinger.Fillintheblanksbelow.

MNW C6radiculopathyHistory

Sensory

Motor

ReflexesSpecialTests

AnswerCase4MNW C6radiculopathy

History Noctornal paresthesia NeckpainRadicularpainSx worsewithneckmotion

Sensory PalmarsparingInvolvesdigit3(C7)


Motor Lumbricles 1&2, FPB,APB,OP

Biceps, brachialis,brachioradialis,wristextension

Reflexes None Biceps,brachioradialis

SpecialTests CarpeltunnelcompressiontestPhalen’sTinel’s

Spurling’sHorner’s

References:Blumenfeld Hal.NeuroanatomythroughClinicalCases.SecondEdition.2010.

PrestonDavid,ShapiroBarbara.ElectromyographyandNeuromuscularDisorders,3rd Edition.2013

DavidFelten,AnilShetty.Netter’sAtlasofNeuroscience.2ndEdition.2003

ToddOlson,Wojchiech Pawlina.StudentAtlasofAnatomy.2nd Edition

Uptodate.comhttp://www.uptodate.com/contents/treatment-and-prognosis-of-cervical-radiculopathy?source=search_result&search=cervical+radiculopathy&selectedTitle=2~32

http://www.uptodate.com/contents/clinical-features-and-diagnosis-of-cervical-radiculopathy?source=search_result&search=cervical+radiculopathy&selectedTitle=1~32

http://www.uptodate.com/contents/ulnar-neuropathy-at-the-elbow-and-wrist?source=search_result&search=median+neuropathy+at+the+wrist&selectedTitle=3~150

http://www.uptodate.com/contents/carpal-tunnel-syndrome-etiology-and-epidemiology?source=search_result&search=median+neuropathy+at+the+wrist&selectedTitle=12~150

http://www.uptodate.com/contents/carpal-tunnel-syndrome-treatment-and-prognosis?source=search_result&search=median+neuropathy+at+the+wrist&selectedTitle=11~150

http://www.uptodate.com/contents/acute-lumbosacral-radiculopathy-pathophysiology-clinical-features-and-diagnosis?source=search_result&search=lumbar+radiculopathy&selectedTitle=1~39

Documents

Limb Weakness: Radiculopathies and Compressive Disorders · Myotome Definition: Muscles innervated by a single nerve root = myotome Nerve ... • Sensory parethesiaor hypoesthesia