SensorySensory--MotorMotor ControlControl ofof thethe UpperUpper Limb:Limb: EffectsEffects ofof ChronicChronic PainPain

Dr.Dr. VictoriaVictoria Galea,Galea, PhDPhD AssociateAssociate ProfessorProfessor SchoolSchool ofof RehabilitationRehabilitation ScienceScience McMasterMcMaster University,University, CANADACANADA ObjectivesObjectives •• ReviewReview ofof neuralneural innervationinnervation ofof thethe upperupper limblimb (UL)(UL) –– BrachialBrachial Plexus.Plexus.

•• SensorySensory--motormotor connectionsconnections betweenbetween thethe centralcentral nervousnervous systemsystem andand upperupper limb.limb.

•• InternalInternal ModelsModels ofof motormotor control:control: ForwardForward Models.Models. BasisBasis forfor MotorMotor Coordination.Coordination.

•• FunctionalFunctional compromisecompromise ofof thethe ULUL duedue toto chronicchronic neckneck pain.pain. – Recent studies on Upper Limb coordination during a functional task. ReviewReview ofof neuralneural innervationinnervation ofof thethe upperupper limblimb (UL)(UL) –– BrachialBrachial Plexus.Plexus. NeuralNeural InnervationInnervation

•• TheThe brachialbrachial plexusplexus isis formedformed fromfrom 55 ventralventral ramirami (C5(C5 -- T1)T1) •• 66 divisionsdivisions – 3 anterior divisions – 3 posterior divisions •• 33 TrunksTrunks •• 33 CordsCords •• 55 PeripheralPeripheral NervesNerves – Branches • Important neural structures for shoulder girdle and joint: – Dorsal Scapular N. • Levator S; Rhomboids – Suprascapular • Supraspinatus, Infraspinatus – Long Thoracic N. • Serratus Anterior – U and L Subscapular N. • Subscapularis, Teres Major – Thoracodorsal N. • Lat. Dorsi – Lat and Med Pectoral • Pec. Major (LP), Pec Minor (LP, MP)

• Important Neural structures for the arm: – Axillary N. • Deltoid; Teres Minor – Musculocutaneous N. • Coracobrachialis; Biceps, Brachialis – Radial (P. Cord) • Triceps, brachioradialis, supinoator, all extrinsic extensors – Median (Med & Lat Cord) • Pronator Teres, Most Extrinsic Flexors, Thenar muscles and 1st 2 lumbricals – Ulnar (Med. Cord) • Flexor Carpi Ulnaris, FDP III & IV, all other intrinsic hand muscles. SensorySensory--motormotor connectionsconnections betweenbetween thethe centralcentral nervousnervous systemsystem andand upperupper limblimb MotorMotor SystemsSystems StructuralStructural ReminderReminder

From “Raise MR Peripheral nerve injuries in the dog, Part II Compendium on Continuing Education for the Small Animal Practitioner 1 269 276, 1979) CorticospinalCorticospinal TractTract ((AKAAKA PPyramidalyramidal Tract)Tract) •• TwoTwo groupsgroups ofof fibersfibers – Corticospinal tract – Corticobulbar tract •• FibresFibres originateoriginate inin bothboth thethe frontalfrontal andand parietalparietal lobeslobes •• LateralLateral CSPtCSPt decussatesdecussates atat thethe medullarymedullary pyramidspyramids SensorySensory SystemsSystems StructuralStructural ReminderReminder

From “Raise MR Peripheral nerve injuries in the dog, Part II Compendium on Continuing Education for the Small Animal Practitioner 1 269 276, 1979) AfferentAfferent EventsEvents ImportantImportant toto thethe ControlControl ofof MovementMovement

•• ExteroceptionExteroception

•• ProprioceptionProprioception ExteroceptionExteroception CutaneousCutaneous MechanoreceptorsMechanoreceptors SegmentalSegmental signalingsignaling ofof sensorysensory ReceptorsReceptors

•• AfferentAfferent informationinformation isis carriedcarried viavia myelinatedmyelinated fibersfibers toto thethe dorsaldorsal hornhorn

•• AxonsAxons havehave varyingvarying propertiesproperties ProprioceptionProprioception ProprioceptionProprioception

•• , is mediated via proprioceptors.

•• Proprioceptive feedback provides information from stimuli generated by the system itself. Examples are the mechanical variables associated with activation of muscle (length, velocity, tension).

•• Proprioceptors are involved in the moment-to- moment control of movement and include, muscle spindles, tendon organs and joint receptors (e.g. deep joint receptors in cervical vertebral joints). TheThe StretchStretch ReflexReflex

•• TheThe stretchstretch reflexreflex isis aa reflectionreflection ofof thethe ““phasicphasic”” componentscomponents ofof musclemuscle spindlesspindles

•• TonicTonic componentscomponents conveyconvey importantimportant staticstatic informationinformation aboutabout musclemuscle lengthlength TheThe DorsalDorsal ColumnsColumns MajorMajor PathwayPathway forfor TouchTouch andand ProprioceptionProprioception The peripheral sensing of the joint angles and skin deformation. The peripheral sensing of muscle lengths and their changes by muscle spindles. The peripheral sensing of muscle forces generated by Golgi tendon organs. The reference (corollary) copies of the instructions sent by the CNS middle level to alpha and gamma motor neurons. The peripheral sensing of the joint angles and skin deformation. The peripheral sensing of muscle lengths and their changes by muscle spindles. The peripheral sensing of muscle forces generated by Golgi tendon organs. The reference (corollary) copies of the instructions sent by the CNS middle level to alpha and gamma motor neurons. • • • • • • • •

The CNS knows what a muscle is actually doing The CNS knows what a muscle is actually doing from decoded information four input sources: from decoded information four input sources: CorticalCortical StructuresStructures InvolvedInvolved inin MotorMotor CoordinationCoordination AreasAreas ofof BrainBrain involvedinvolved inin MotorMotor ControlControl

• Lots of “traffic” involved in the planning, execution and shaping of movement

• Areas of the frontal lobe are involved in the planning and execution of movement . Areas of the are involved in the ongoing performance and shaping of movement.

• Many sources of communication between cortical areas and sub- cortical areas such as the . InternalInternal ModelsModels ofof MotorMotor Control.Control. ForwardForward Models:Models: BasisBasis forfor MotorMotor CoordinationCoordination InternalInternal ModelsModels ofof MotorMotor ControlControl

TheThe acquisitionacquisition ofof complexcomplex motormotor skillsskills isis facilitatedfacilitated byby thethe formationformation ofof internalinternal modelsmodels whichwhich areare neuralneural representationsrepresentations ofof thethe inputinput-- outputoutput characteristicscharacteristics ofof thethe motormotor systems.systems.

TheThe cerebellumcerebellum containscontains inverseinverse oror forwardforward modelsmodels ofof thethe motormotor system.system. InternalInternal ModelsModels ofof MotorMotor ControlControl • Mathematically, the term internal model refers to two transformations:

– Forward model – the set of operations that change a motor command into motor behaviour.

• Forward Internal Models can predict sensory consequences from efference copies of issued motor commands

– Inverse Model – The set of operations needed to retrieve a motor command from motor behaviour.

• Inverse Internal Models – Can calculate necessary feedforward motor commands from desired trajectory information CoordinationCoordination ofof GripGrip--ForceForce LoadLoad--ForceForce CouplingCoupling • When holding an object with the tips of the fingers there is a frictional force exerted to keep the object from slipping.

• This is precisely controlled so that it is just slightly greater than the minimum force needed to prevent slip.

• This coupling is explained by a framework that contains both inverse and forward models of the arm. InternalInternal ModelsModels ofof MotorMotor ControlControl

fMRIfMRI studiesstudies havehave revealedrevealed cerebellarcerebellar activityactivity specificspecific toto gripgrip--forceforce –– loadload--forceforce coupling,coupling, suggestingsuggesting thethe existenceexistence ofof forwardforward modelsmodels inin thethe cerebellumcerebellum CervicalCervical MuscleMuscle CoordinationCoordination WhiplashWhiplash AssociatedAssociated DisorderDisorder NeuromuscularNeuromuscular ActivationActivation ModelModel

•• TheThe presencepresence ofof pain:pain: – Alters the activity of muscles during functional movement. – Specifically – inhibition or delayed activation of muscles. – There are suggestions that this occurs in the deep muscles involved in joint stability. – The action of the superficial muscles is reflective of a compensation for loss of joint stability. – SterlSterling,ing, Jull & Wright, 2001 DisruptionDisruption inin MuscleMuscle ActivationActivation withwith NeckNeck PainPain duringduring ULUL Flexion/Extension.Flexion/Extension.

•• Note pattern of activation in controls. – This is a feedforward neural strategy pre-planned by CNS structures. •• Note delayed activation in Neck Pain Patients.

•• Automatic Neuromuscular control may not be optimal. – Falla et al, 2004 ClinicalClinical ImplicationsImplications

•• DeepDeep CervicalCervical FlexorsFlexors havehave toto bebe broughtbrought backback ““onon--lineline”” forfor properproper posturalpostural adjustmentsadjustments toto taketake place.place.

•• TheThe actionaction ofof thethe superficialsuperficial neckneck flexorsflexors andand extensorsextensors isis notnot sufficientlysufficiently ““finefine”” forfor stabilitystability ofof thethe cervicalcervical spinespine duringduring upperupper limblimb movements.movements. TestTest forfor CervicoKinestheticCervicoKinesthetic Ability:Ability:

““TheThe FlyFly””.. Kristjanssen et al, 2004 ClinicalClinical ImplicationsImplications

•• ProprioceptiveProprioceptive acuityacuity isis disrupted.disrupted.

•• FurtherFurther compoundingcompounding thethe problemproblem inin motormotor controlcontrol ofof thethe neckneck andand armarm

•• TheseThese teststests maymay bebe usedused toto traintrain proprioceptiveproprioceptive functionfunction inin patientspatients withwith Neck/ArmNeck/Arm painpain andand functionalfunctional disability.disability. UpperUpper LimbLimb CoordinationCoordination StudiesStudies inin PatientsPatients withwith MechanicalMechanical NeckNeck DisorderDisorder (MND)(MND) MND:MND: ImplicationsImplications toto CervicalCervical FunctionFunction

•• WithWith neckneck painpain andand headache:headache: – Upper and deep cervical flexors lose their endurance. Watson & Trott, 1993; Beeton & JuJulll,l, 1994 – Superficial muscles (such as scalenes and sternocleidomastoid) have to compensate. – Atrophy of posterior suboccipital muscles has been noted. – Compensation via upper trapezius and levator scapulae. – Decreased proprioceptive acuity in cervical spine structures. ReveRevell et aall , 1994 FunctionalFunctional ImplicationsImplications •• IfIf thethe deepdeep musclesmuscles areare dysfunctionaldysfunctional thenthen stabilizationstabilization ofof articulararticular segmentssegments duringduring movementmovement isis compromised.compromised.

•• SuperficialSuperficial musclesmuscles primarilyprimarily concernedconcerned withwith thethe performanceperformance ofof thethe tasktask areare beingbeing calledcalled uponupon toto performperform functionsfunctions thatthat theythey werewere notnot designeddesigned for.for.

•• AlteredAltered patternspatterns ofof musclemuscle activationactivation seemseem toto bebe sustainedsustained beyondbeyond thethe acuteacute stagestage andand maymay contributecontribute toto thethe chronicitychronicity ofof thethe problem.problem. CyclicalCyclical ReachReach andand GraspGrasp TestTest (CRGT)(CRGT)

Dr.Dr. VictoriaVictoria Galea,Galea, PhDPhD Dr.Dr. MichaelMichael PierrynowksiPierrynowksi,, PhDPhD Dr.Dr. JoyJoy MacDermid,MacDermid, PhD,PhD, PTPT AnitaAnita Gross,Gross, MScMSc,, BScBSc (PT),(PT), FCAMTFCAMT QuestionsQuestions ??????

•• DoDo patientspatients withwith MNDMND exhibit:exhibit: •• DifferentDifferent neuralneural strategies?strategies? •• AlteredAltered kinematics?kinematics? •• HowHow doesdoes thisthis affectaffect thethe patientpatient’’ss abilityability toto formform internalinternal models?models? ToTo updateupdate thethe forwardforward model?model? DifferentDifferent NeuralNeural StrategiesStrategies ShoulderShoulder GirdleGirdle (and(and Joint)Joint) ActivationActivation

80 80 60 60 40 40 20 20 0 80 80 60 60 40 40 20 20 UTrap 0 UTrap 80 80 60 SerAnt 60 SerAnt 40 40 20 20 ADel 0 ADel 80 80 60 PDel 60 PDel 40 40 20 InfSp 20 InfSp 0 80 LTrap 80 LTrap 60 60 40 40 20 20 0 80 80 60 60 40 40 20 20 0 10000 20000 30000 40000 50000 60000 70000 10000 20000 30000 40000 50000 60000 70000 Patient MND 2 Control MND 0 GroupGroup DataData

0.9 X-Correlation Pairs 0.88

0.86 ) 0.84 orrel ati on (r

C 0.82

0.8 C1 C2 C3 C4 C5 C6

0.78

Muscle pairs Muscle X-Correlations P's Muscle X-Correlations C's MND: U TRAP vs Ser ANT Typical: U TRAP vs Ser ANT

1 1

0.95 0.95 )

0.9 ) 0.9 r r ( (

0.85 0.85 Correlation Correlation 0.8 Correlation 0.8

0.75 0.75

0.7 0.7

BEG MID END BEG MID END

PAT PAD PUD PUT CAD CAT CUD CUT

P/C = Patient/Control; A/U = Affected/Unaffected Side; D/T = Standing/Sitting ConclusionsConclusions •• TheThe relationshiprelationship betweenbetween UpperUpper TrapeziusTrapezius andand SerratusSerratus AnteriorAnterior isis importantimportant toto shouldershoulder girdlegirdle stabilization.stabilization.

•• WeWe proposepropose thatthat thesethese resultsresults areare evidenceevidence ofof aa disruptiondisruption ofof thethe neuromuscularneuromuscular controlcontrol ofof thethe shouldershoulder girdle.girdle. AnAn inabilityinability toto updateupdate thethe forwardforward model.model.

•• ThisThis hashas implicationsimplications toto upperupper limblimb coordinationcoordination particularlyparticularly duringduring challengingchallenging taskstasks requiringrequiring patientspatients withwith MNDMND toto reachreach aboveabove theirtheir heads.heads. AlteredAltered Kinematics?Kinematics? TheThe Challenge!!Challenge!!

•• HowHow dodo youyou taketake aa structurestructure withwith 33 jointsjoints eacheach withwith 6df6df attachedattached toto aa movingmoving trunktrunk controlledcontrolled byby manymany musclesmuscles (many(many ofof themthem multimulti--joint)joint) andand reducereduce itit toto aa singlesingle number!!!number!!! ShoulderShoulder DuringDuring SittingSitting Trial.Trial.

Shoulder Sitting P vs C

0.60

0.50

0.40

Variance 0.30

0.20

0.10

0.00

A Group Side UA Patients Controls ElbowElbow DuringDuring SittingSitting Trial.Trial.

Elbow Sitting P vs C

0.60

0.50

0.40

Variance 0.30

0.20

0.10 Patients 0.00 Controls A UA Group Side CRGTCRGT

•• CRGTCRGT differentiatesdifferentiates

– Patients from Controls – Seated from Standing – Shoulder from elbow

•• ShowingShowing promisepromise asas aa clinicalclinical tool.tool. ObservationsObservations

•• SignificantSignificant CorrelationCorrelation betweenbetween UpperUpper TrapeziusTrapezius andand SerratusSerratus Anterior.Anterior. (p(p ≤≤0.10).0.10).

•• TrendsTrends inin UpperUpper TrapeziusTrapezius andand LowerLower TrapeziusTrapezius (C1)(C1) andand SerratusSerratus AnteriorAnterior andand InfraspinatusInfraspinatus (C6).(C6).

•• ThereThere werewere nono significantsignificant groupgroup effectseffects inin thethe otherother correlationscorrelations howeverhowever significantsignificant interactionsinteractions betweenbetween postureposture andand sideside werewere observed.observed. ClinicalClinical ImplicationsImplications •• Over-activity in large superficial muscles compound the problem for the deep postural muscles.

•• The shoulder girdle requires the coordinated action of several muscles in order to function “rhythmically” with the upper limb in complex movements.

•• Rehabilitation should include testing using functional tasks and re-training with the integration of sensory- motor systems in mind – i.e. task related therapy. ConclusionsConclusions ((basedbased onon InternalInternal ModelsModels).).

WeWe proposepropose thatthat therethere waswas aa disruptiondisruption ofof thethe neuromuscularneuromuscular controlcontrol ofof thethe shouldershoulder girdlegirdle leadingleading toto possiblepossible disruptiondisruption inin upperupper limblimb coordinationcoordination duringduring thesethese tasks.tasks.

ThisThis maymay representrepresent aa disruptiondisruption ofof thethe dynamicdynamic forwardforward modelmodel thatthat informsinforms thethe internalinternal modelmodel responsibleresponsible forfor posturalpostural stabilitystability ofof thethe shouldershoulder girdlegirdle duringduring (high)(high) reachreach andand graspgrasp tasks.tasks. ProjectsProjects inin thethe HumanHuman MovementMovement LaboratoryLaboratory

• Basic – Neural strategies during performance of hypnoticomotor tasks. Effect on cerebellar activity – Developmental reach and grasp tasks. • Applied studies: Adult – Upper limb coordination in chronic pain patients with mechanical neck disorder – Cervical proprioception and postural control after induced perturbations of cervical spine – Effects of interferential current on chronic neck pain: InterX device clinical trial. • Applied Studies: Paediatric – Upper limb function in children with cerebral palsy – Assessment of in children with cerebral palsy – Effects of Artane on upper limb function in children with dyskinetic cerebral palsy – Upper limb motor control in children born with Obstetrical Brachial Plexus Injury – Upper limb coordination in children with Developmental Coordination Disorder. ContactContact InformationInformation Dr.Dr. VictoriaVictoria Galea,Galea, PhDPhD AssociateAssociate ProfessorProfessor SchoolSchool ofof RehabilitationRehabilitation ScienceScience FacultyFaculty ofof HealthHealth SciencesSciences McMasterMcMaster UniversityUniversity 14001400 MainMain StreetStreet WestWest Hamilton,Hamilton, OntarioOntario CANADACANADA L8SL8S 1C71C7 Phone:Phone: 001001 905905 525525 91409140 #22189,#22189, lablab #24174#24174 Email:Email: [email protected]@mcmaster.ca