Limb Weakness: Radiculopathies and Compressive Disorders · Myotome Definition: Muscles innervated...

LimbWeakness:RadiculopathiesandCompressiveDisorders

SpotthebraincellDr.TheoMobachPGY-4Neurology

tmmobach@gmail.com

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

Image:Olson,Pawlina.StudentAtlasofAnatomy.2ndEdition

Dermatome

Definition:

Asensoryregionofskininnervatedbyanerveroot=dermatome

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

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

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

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

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

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

Image:Preston,Shupiro.ElectromyographyandNeuromuscularDisorders.3rd Edition

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)

Image:Preston,Shupiro.ElectromyographyandNeuromuscularDisorders.3rd Edition

MNWDdxPeripheralNervousSystem• Proximalmedianneuropathy• Medialcordorlowertrunklesion• C6radiculopathy

CentralNervousSystem• Stroke:lacunar,corticalhand• Myelopathy• Demyelinatinglesion

Image:Preston,Shupiro.ElectromyographyandNeuromuscularDisorders.3rd Edition

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

Image:Preston,Shupiro.ElectromyographyandNeuromuscularDisorders.3rd Edition

UlnarNerveAnatomy• DerivedfromC8/T1

Nerveroots

• Nobranchesinthearm

• Ulnargroove:formedbetweenmedialepicondyleandolecrenon

• TravelsthroughthewristviaGuyon’s canal

Image:Preston,Shupiro.ElectromyographyandNeuromuscularDisorders.3rd Edition

• 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

Image:Preston,Shupiro.ElectromyographyandNeuromuscularDisorders.3rd Edition

UlnarNeuropathyExam

BenedictssignFroment sign

Wartenberg sign

Image:Preston,Shupiro.ElectromyographyandNeuromuscularDisorders.3rd Edition

Ulnarneuropathyexam

Image:Preston,Shupiro.ElectromyographyandNeuromuscularDisorders.3rd Edition

Ulnarvs C8/T1Ulnar C8/T1radiculopathy

History Compressionorstretchmechanismof injury

NeckpainRadicularpainSx worsewithneckmotion

Sensory Medial dorsalandvolaraspectofthehand

Sensorychanges extendpastthewrist

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

Image:Preston,Shupiro.ElectromyographyandNeuromuscularDisorders.3rd Edition

FibularNerveAnatomy

Image:Preston,Shupiro.ElectromyographyandNeuromuscularDisorders.3rd Edition

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

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

Radiculopathies• Sensoryormotordysfunctiondue

topathologyofanerveroot

• Clinical– Pain– Weaknesswithinamyotome– Sensorychangeswithina

dermatome– Antecedentevents:trauma,heavy

lifting,physicalexertion• Onset

– Acute:suggestsdiscogenic etiology(youngerage,20%)

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

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

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

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

Radiculopathies

CommonLocations– C6andC7mostcommon

cervicalradiculopathies

– L5andS1mostcommonlumbosacralradiculopathies

– 2/3ofdiscogenicradiculopathiesoccurinthelumbosacralregion

Image:Olson,Pawlina.StudentAtlasofAnatomy.2ndEdition

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

Image:Olson,Pawlina.StudentAtlasofAnatomy.2ndEdition

AlternativeEtiologies

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

Review

QuizCases

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

Quiz

Image:Preston,Shupiro.ElectromyographyandNeuromuscularDisorders.3rd Edition

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)

Sensorychanges extendpastthewrist

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

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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