Re-establishing Re-establishing Neuromuscular ControlNeuromuscular Control

Why is it critical to the Why is it critical to the rehabilitation process?rehabilitation process?

Refocuses the athlete’s awareness of peripheral Refocuses the athlete’s awareness of peripheral sensation & guides them into more coordinated sensation & guides them into more coordinated motor strategiesmotor strategies

Required to:Required to: Protect joints from excessive strainProtect joints from excessive strain Provide prophylactic mechanism to recurrent injuryProvide prophylactic mechanism to recurrent injury

Complements traditional components of Complements traditional components of rehabilitationrehabilitation

We rely on sensory information from the periphery We rely on sensory information from the periphery from our visual, vestibular, & somatosensory from our visual, vestibular, & somatosensory systems.systems.

Primary role of articular structuresPrimary role of articular structures Stabilize & guide body segmentsStabilize & guide body segments Provide mechanical restraint to abnormal joint Provide mechanical restraint to abnormal joint

motionmotion Dynamic restraint systemDynamic restraint system Capsuloligamentous tissue & musculotendon Capsuloligamentous tissue & musculotendon

receptor sensory rolereceptor sensory role Detect joint motion & positionDetect joint motion & position Detect changes in muscle lengthDetect changes in muscle length Implicated in regulating muscle stiffness prior to loadingImplicated in regulating muscle stiffness prior to loading

Injury results in damage to microscopic nerves Injury results in damage to microscopic nerves associated with peripheral mechanoreceptorsassociated with peripheral mechanoreceptors Disrupts sensory feedback Disrupts sensory feedback Alters reflexive joint stabilization & neuromuscular Alters reflexive joint stabilization & neuromuscular

coordinationcoordination

Four critical elements of neuromuscular control Four critical elements of neuromuscular control in rehabin rehab Joint sensation (position, motion, force)Joint sensation (position, motion, force) Dynamic stability Dynamic stability Preparatory & reactive muscle characteristicsPreparatory & reactive muscle characteristics Conscious & unconscious functional motor patternsConscious & unconscious functional motor patterns

Rehabilitation should address feedback systemsRehabilitation should address feedback systems Preparatory (feed-forward)Preparatory (feed-forward) Reactive (feed-back)Reactive (feed-back)

Muscle sense is divided into 4 sensory functions:Muscle sense is divided into 4 sensory functions: Sensation of passive movementSensation of passive movement Sensation of active movementSensation of active movement Sensation of positionSensation of position Sensations of heaviness & resistanceSensations of heaviness & resistance

What is neuromuscular control?What is neuromuscular control? Signal transmission through afferent sensory pathways Signal transmission through afferent sensory pathways

ProprioceptionProprioception Conscious & unconscious appreciation of joint positionConscious & unconscious appreciation of joint position Awareness of position & movement Awareness of position & movement Any postural, positional or kinetic info provided to the CNS by Any postural, positional or kinetic info provided to the CNS by

sensory receptors in muscles, tendons or jointssensory receptors in muscles, tendons or joints

KinesthesiaKinesthesia Sensation of joint motion or accelerationSensation of joint motion or acceleration Sensation of Sensation of ACTIVEACTIVE movement (contracting muscle)movement (contracting muscle)

Neuromuscular controlNeuromuscular control Efferent motor responseEfferent motor response to sensory information to sensory information Proprioception & kinesthesiaProprioception & kinesthesia

Motor control mechanismsMotor control mechanisms Feed-forward neuromuscular controlFeed-forward neuromuscular control

Planning movements based on sensory information from Planning movements based on sensory information from past experiencespast experiences

Preparatory muscle activityPreparatory muscle activityOperates on premise of initiating a motor response in Operates on premise of initiating a motor response in

anticipation of a load or activityanticipation of a load or activity

Feed-back neuromuscular controlFeed-back neuromuscular controlContinuously regulates muscle activity through reflexive Continuously regulates muscle activity through reflexive

pathwayspathwaysReactive muscle activityReactive muscle activityOperates directly in response to a potentially Operates directly in response to a potentially

destabilizing event, using a normal reference pointdestabilizing event, using a normal reference point

Muscle stiffnessMuscle stiffness Ratio in change of force to change in lengthRatio in change of force to change in length Stiffer muscles resist stretching = more effective restraint to Stiffer muscles resist stretching = more effective restraint to

joint displacementjoint displacement Modified by muscle activationModified by muscle activation

Activities for Inducing Activities for Inducing AdaptationsAdaptations

Open & closed kinetic chain activitiesOpen & closed kinetic chain activities Balance trainingBalance training Eccentric & high repetition low load Eccentric & high repetition low load

exercisesexercises Reflex facilitationReflex facilitation Stretch-shorteningStretch-shortening Biofeedback trainingBiofeedback training Controlled positions of vulnerabilityControlled positions of vulnerability

Physiology of MechanoreceptorsPhysiology of MechanoreceptorsArticular MechanoreceptorsArticular Mechanoreceptors

Specialized nerve endings that transduce Specialized nerve endings that transduce mechanical tissue deformation into frequency mechanical tissue deformation into frequency modulated neural signalsmodulated neural signals

Increased tissue deformation results in increased afferent Increased tissue deformation results in increased afferent firing rate or rise in quantity of mechanoreceptors firing rate or rise in quantity of mechanoreceptors activatedactivated

TypesTypesPacinian corpusclesPacinian corpuscles – (Type II) sensitive to high-frequency – (Type II) sensitive to high-frequency

vibration; compression sensitivevibration; compression sensitiveRuffini endingsRuffini endings – (Type I) sensitive to stretching of the – (Type I) sensitive to stretching of the

joint capsulejoint capsuleGolgi-Mazzoni corpusclesGolgi-Mazzoni corpuscles – (Type III) sensitive to joint – (Type III) sensitive to joint

compression, not joint motioncompression, not joint motionFree nerve endingsFree nerve endings – (Type IV) stimulated by pain & – (Type IV) stimulated by pain &

inflammation when a joint is placed in an end positioninflammation when a joint is placed in an end position Normally not active in normal joint movementNormally not active in normal joint movement

Quick adapting (QA)Quick adapting (QA)Cease discharging shortly after onset of Cease discharging shortly after onset of

stimulusstimulusProvide conscious & unconscious kinesthetic Provide conscious & unconscious kinesthetic

sensation in response to joint sensation in response to joint movement/accelerationmovement/acceleration

Type IIType II

Slow adapting (SA)Slow adapting (SA)Continue to discharge as long as stimulus is Continue to discharge as long as stimulus is

presentpresentContinuous feedback & proprioceptive Continuous feedback & proprioceptive

information relative to joint positioninformation relative to joint positionType I, IIIType I, III

Articular Articular MechanoreceptorsMechanoreceptors

Musculotendon MechanoreceptorsMusculotendon MechanoreceptorsMuscle spindlesMuscle spindles – located in the muscle – located in the muscle

Responds to stretch of a muscleResponds to stretch of a muscle Detects length & rate of length changes Detects length & rate of length changes

Its stimulation leads to a contractionIts stimulation leads to a contraction Transmit information via afferent nervesTransmit information via afferent nerves Innervated by small motor fibers (gamma efferents)Innervated by small motor fibers (gamma efferents) Project directly on motoneurons (monosynaptic Project directly on motoneurons (monosynaptic

reflexes)reflexes) Stretch reflexStretch reflex

Stimulation results in reflex contractionStimulation results in reflex contraction Continued stimulation (gamma motor nerves) heighten Continued stimulation (gamma motor nerves) heighten

stretch sensitivitystretch sensitivity Muscle activity mediationMuscle activity mediation

Musculotendon Musculotendon MechanoreceptorsMechanoreceptors

Golgi Tendon Organs (GTO)Golgi Tendon Organs (GTO) – located – located in tendon & musculotendon junctionin tendon & musculotendon junction Detects tension within a muscle & responds to Detects tension within a muscle & responds to

both the contraction & stretching of a muscleboth the contraction & stretching of a muscleRegulate muscle activity & tensionRegulate muscle activity & tension

Its stimulation results in muscle relaxationIts stimulation results in muscle relaxation

GTO’s have opposite effect of muscle GTO’s have opposite effect of muscle spindles by producing a relaxation in spindles by producing a relaxation in the muscle being loadedthe muscle being loaded

Neural Pathways of Peripheral Neural Pathways of Peripheral AfferentsAfferents

Encoded signalsEncoded signals - transmitted from peripheral receptors via - transmitted from peripheral receptors via afferent pathways (interneurons) to CNSafferent pathways (interneurons) to CNS

Brain Stem = BalanceBrain Stem = Balance Primary proprioceptive correlation centerPrimary proprioceptive correlation center

Cerebral CortexCerebral Cortex – location of conscious movement – location of conscious movement

Monosynaptic reflex pathway -Monosynaptic reflex pathway - links muscle spindles links muscle spindles directly to motor nervesdirectly to motor nerves

BalanceBalance Influenced by peripheral afferent mechanism mediating joint Influenced by peripheral afferent mechanism mediating joint

proprioceptionproprioception Partially dependent on inherent ability to integrate joint position Partially dependent on inherent ability to integrate joint position

sense, vision & vestibular apparatus with neuromuscular controlsense, vision & vestibular apparatus with neuromuscular control

Re-establishing Neuromuscular Re-establishing Neuromuscular ControlControl

Injuries result in decreases in neuromuscular Injuries result in decreases in neuromuscular controlcontrol

Pathoetiology Pathoetiology Injury results in deafferentation of ligament & Injury results in deafferentation of ligament &

capsular mechanoreceptorscapsular mechanoreceptors Joint inflammation & pain compound sensory deficitsJoint inflammation & pain compound sensory deficits Congenital/pathological joint laxity have diminished Congenital/pathological joint laxity have diminished

ability to detect joint motion & positionability to detect joint motion & positionProprioceptive, kinesthetic deficits & mechanical instability Proprioceptive, kinesthetic deficits & mechanical instability

lead to functional instabilitylead to functional instability

Objectives for Neuromuscular RehabilitationObjectives for Neuromuscular Rehabilitation Develop/re-establish Develop/re-establish afferent & efferent afferent & efferent

characteristicscharacteristics that enhance dynamic stability that enhance dynamic stability ElementsElements

Proprioceptive & kinesthetic sensationProprioceptive & kinesthetic sensation Dynamic joint stabilizationDynamic joint stabilization Reactive neuromuscular controlReactive neuromuscular control Functional motor patternsFunctional motor patterns

Afferent & Efferent CharacteristicsAfferent & Efferent Characteristics Sensitivity of peripheral receptorsSensitivity of peripheral receptors Facilitation of afferent pathwaysFacilitation of afferent pathways Muscle stiffnessMuscle stiffness Onset rate & magnitude of muscle activityOnset rate & magnitude of muscle activity Simultaneous activation of agonist/antagonistSimultaneous activation of agonist/antagonist Reflexive & discriminatory muscle activation Reflexive & discriminatory muscle activation

Neuromuscular Neuromuscular CharacteristicsCharacteristics Peripheral Afferent ReceptorsPeripheral Afferent Receptors

Altered peripheral afferent information may disrupt motor Altered peripheral afferent information may disrupt motor control & functional stabilitycontrol & functional stability

Repetitious athletic activity enhances proprioceptive & Repetitious athletic activity enhances proprioceptive & kinesthetic acuity = facilitated afferent pathwayskinesthetic acuity = facilitated afferent pathways

Enhanced joint motion awareness improves feed-forward & Enhanced joint motion awareness improves feed-forward & feedback mechanismsfeedback mechanisms

Muscle StiffnessMuscle Stiffness Significant role in preparatory & reactive dynamic restraintsSignificant role in preparatory & reactive dynamic restraints Exercises that encourage muscle stiffness should be Exercises that encourage muscle stiffness should be

incorporated into rehabilitation programsincorporated into rehabilitation programs Eccentric exercisesEccentric exercises Chronic overload results in connective tissue proliferation, Chronic overload results in connective tissue proliferation,

desensitizing GTO’s & increase muscle spindle activitydesensitizing GTO’s & increase muscle spindle activity Power trained vs. Endurance trained athletesPower trained vs. Endurance trained athletes

Power athlete = Faster muscle pre-activation (EMG)Power athlete = Faster muscle pre-activation (EMG) Endurance athlete = Increased baseline motor toneEndurance athlete = Increased baseline motor tone

Reflexive Muscle ActivationReflexive Muscle Activation Reflex latency times may be dependent on Reflex latency times may be dependent on

types of training (endurance vs. power)types of training (endurance vs. power) Preparatory & reactive muscle activation might Preparatory & reactive muscle activation might

improve dynamic stability & function if muscle improve dynamic stability & function if muscle stiffness is enhanced in deficient jointsstiffness is enhanced in deficient joints

Decreasing electromechanical delay between Decreasing electromechanical delay between joint loading & protective muscle activation joint loading & protective muscle activation can increase stability & functioncan increase stability & function

Discriminate Discriminate Muscle ActivationMuscle Activation Unconscious control Unconscious control

of muscle activity is of muscle activity is critical in balance & critical in balance & coordination coordination

May initially require May initially require conscious activation conscious activation prior to unconscious prior to unconscious controlcontrol

Use of biofeedback Use of biofeedback can aid in this can aid in this processprocess

Help eliminate Help eliminate imbalances & re-imbalances & re-establish preparatory establish preparatory & reactive muscle & reactive muscle activityactivity

Elements for Neuromuscular Elements for Neuromuscular ControlControl

Proprioception & Kinesthesia TrainingProprioception & Kinesthesia Training Restore neurosensory propertiesRestore neurosensory properties Enhance sensitivity of uninvolved peripheral Enhance sensitivity of uninvolved peripheral

afferentsafferents Joint compression is believed to maximally stimulate Joint compression is believed to maximally stimulate

articular receptorsarticular receptors Closed chain exercises through available ROMClosed chain exercises through available ROM

Early repositioning tasks are criticalEarly repositioning tasks are critical Conscious to unconscious joint awarenessConscious to unconscious joint awareness

Applying neoprene sleeve or ace wrap stimulates Applying neoprene sleeve or ace wrap stimulates cutaneous receptors – additional proprioception & cutaneous receptors – additional proprioception & kinesthesiakinesthesia

Dynamic StabilizationDynamic Stabilization Encourage preparatory agonist/antagonist Encourage preparatory agonist/antagonist

coactivationcoactivation Restores force couples & balances joint forcesRestores force couples & balances joint forces

Results in decreased loads on static structuresResults in decreased loads on static structures Activities that require anticipatory & reactive Activities that require anticipatory & reactive

adjustments to imposed loadsadjustments to imposed loads Combination of balance & stretch shortening Combination of balance & stretch shortening

exercisesexercises Encourages preparatory & reactive muscle activityEncourages preparatory & reactive muscle activity

Closed chain exercises induce coactivation & Closed chain exercises induce coactivation & compressioncompression

Reactive Neuromuscular ControlReactive Neuromuscular Control Stimulates reflex pathwaysStimulates reflex pathways Object is to impose perturbations that stimulate Object is to impose perturbations that stimulate

reflex stabilizationreflex stabilization Can resultCan result in decreased response time & develop in decreased response time & develop

reactive strategies to unexpected joint loadsreactive strategies to unexpected joint loads Perturbations should be unexpected in order to facilitate Perturbations should be unexpected in order to facilitate

reflexive activityreflexive activity Functional ActivitiesFunctional Activities

Objective is to return athlete to pre-injury activityObjective is to return athlete to pre-injury activity Involves sports specific movement patterns Involves sports specific movement patterns

designed to restore functional abilitydesigned to restore functional ability Can be utilized to assess readiness for return to Can be utilized to assess readiness for return to

playplay Stresses peripheral afferents, simultaneous Stresses peripheral afferents, simultaneous

muscle activation, reflexive activitymuscle activation, reflexive activity Progress from conscious to unconsciousProgress from conscious to unconscious Develop functionally specific movement patterns, Develop functionally specific movement patterns,

ultimately decreasing risk of injuryultimately decreasing risk of injury

Lower Extremity Lower Extremity TechniquesTechniques

Techniques should focus on muscle Techniques should focus on muscle groups that require attention groups that require attention Progress from no weight to weight Progress from no weight to weight

assistedassisted Use of closed-chain activities is Use of closed-chain activities is

encouraged encouraged Replicates environmental demandsReplicates environmental demands Plays on principles of neuromuscular Plays on principles of neuromuscular

controlcontrol Joint stabilization exercisesJoint stabilization exercises

Balance & partial weight bearing Balance & partial weight bearing activitiesactivities

Progress non-weight bearing to full Progress non-weight bearing to full weight-bearingweight-bearing

Balance on unstable surfaces can begin Balance on unstable surfaces can begin once full-weight bearingonce full-weight bearing

Slide board exercisesSlide board exercises Stimulates coactivation with increasing muscle force & Stimulates coactivation with increasing muscle force &

enduranceendurance Stimulating dynamic stability & stiffnessStimulating dynamic stability & stiffness

Stair climbing (forward & backward)Stair climbing (forward & backward) Emphasis on eccentric strengthEmphasis on eccentric strength

BiofeedbackBiofeedback Used to develop agonist/antagonist coactivationUsed to develop agonist/antagonist coactivation Encourages voluntary muscle activationEncourages voluntary muscle activation

Stretch-shortening exercisesStretch-shortening exercises Eccentric deceleration & explosive concentric Eccentric deceleration & explosive concentric

contractionscontractions Incorporate early in process (modified loads)Incorporate early in process (modified loads) Involves preparatory & reactive muscle activityInvolves preparatory & reactive muscle activity Hopping progressionHopping progression

Double Double Single leg Single leg Sagittal Sagittal Lateral Lateral Rotational hopping Rotational hopping Surface modificationSurface modification

Rhythmic stabilizationRhythmic stabilization React to joint React to joint

perturbations perturbations preparatory & reactive preparatory & reactive muscle activitymuscle activity

Alterations in loads & Alterations in loads & displacementdisplacement

Unstable surfacesUnstable surfaces Linear & angular Linear & angular

perturbations, altering perturbations, altering center of gravitycenter of gravity

Facilitate reflexive activityFacilitate reflexive activity Ball tossBall toss

Disrupt concentration, Disrupt concentration, induce unconscious induce unconscious response & reactive response & reactive adaptationadaptation

Trampoline HoppingTrampoline Hopping Hopping & landing (double Hopping & landing (double

support, single support, support, single support, rotation)rotation)

Challenge athleteChallenge athlete Hopping & catchingHopping & catching Hopping & landing on Hopping & landing on

varying surfacesvarying surfaces Functional activitiesFunctional activities

Restore normal gaitRestore normal gait Athlete must internalize Athlete must internalize

normal kinematics (swing normal kinematics (swing & stance)& stance)

Utilize retro walking Utilize retro walking (hamstring activity), pool (hamstring activity), pool or unloading devicesor unloading devices

Cross over walking, figure Cross over walking, figure 8’s, cutting, carioca, 8’s, cutting, carioca, changes in speedchanges in speed

Functional activities that Functional activities that simulate demands of sportsimulate demands of sport

Upper Extremity TechniquesUpper Extremity Techniques Work to maintain joint congruency & Work to maintain joint congruency &

functional stabilityfunctional stability Requires dynamic restraint via coordinated Requires dynamic restraint via coordinated

muscle activationmuscle activation Injury to static stabilizersInjury to static stabilizers Failure of dynamic restraint systemFailure of dynamic restraint system

Could result in repetitive loads, compromising Could result in repetitive loads, compromising joint integrity & predisposing athlete to re-injury joint integrity & predisposing athlete to re-injury

Adapt lower extremity exercise for upper Adapt lower extremity exercise for upper extremityextremity

Muscle stiffnessMuscle stiffness Enhance using elastic resistance (focus on Enhance using elastic resistance (focus on

eccentrics)eccentrics) High repetitions & low resistanceHigh repetitions & low resistance Upper extremity ergometers should be Upper extremity ergometers should be

incorporated for enduranceincorporated for endurance

Dynamic stabilizationDynamic stabilization Stability platformsStability platforms Push-ups, horizontal abduction, tracing circles Push-ups, horizontal abduction, tracing circles

on slide board with dominant & non-dominant on slide board with dominant & non-dominant armsarms

Plyometric exercisePlyometric exercise

Reactive Reactive Neuromuscular Neuromuscular ExercisesExercises Manual perturbations Manual perturbations Rhythmic stabilization Rhythmic stabilization

with gradual progressionwith gradual progression Placing joint in inherently Placing joint in inherently

unstable positionsunstable positions Functional TrainingFunctional Training

Developing motor Developing motor patterns in overhead patterns in overhead positionposition

Reproduce demands of Reproduce demands of activityactivity

Emphasis on techniqueEmphasis on technique Re-education of Re-education of

functional patternsfunctional patterns Speed & complexity in Speed & complexity in

movement require rapid movement require rapid integration of sensory integration of sensory informationinformation