ChiroCredit.com presents Biomechanics 310Biomechanics 3101 ChiroCredit.com presents Biomechanics...
Transcript of ChiroCredit.com presents Biomechanics 310Biomechanics 3101 ChiroCredit.com presents Biomechanics...
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ChiroCredit.com presentsChiroCredit.com presentsBiomechanics 310Biomechanics 310Biomechanics 310Biomechanics 310
Presented byPresented byIvo F Waerlop DC, DABCNIvo F Waerlop DC, DABCNShawn Allen, DC, DABCOShawn Allen, DC, DABCO
Advanced Gait EvaluationAdvanced Gait Evaluation
Differences between walking and Differences between walking and running gaitrunning gait
Stance and swing % reversedStance and swing % reversedFaster running gait = less stance phaseFaster running gait = less stance phase
No double support phaseNo double support phaseStride length increasedStride length increasedStride length increasedStride length increasedFaster cadenceFaster cadenceOften no heel strikeOften no heel strikeActions must occur much quickerActions must occur much quickerMore deceleration/accelerationMore deceleration/acceleration
Depending on gaitDepending on gait
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Walking Gait SummaryWalking Gait Summary
Stance Stance –– 62%62%Weight acceptanceWeight acceptance
Initial contactInitial contactLoading responseLoading response
Swing Swing -- 38%38%Swing limb advancementSwing limb advancement
PreswingPreswingLoading responseLoading response
Single limb supportSingle limb supportMid stanceMid stanceTerminal stanceTerminal stance
Swing limb Swing limb advancementadvancement
preswingpreswing
Initial swingInitial swingMid swing Mid swing Terminal swingTerminal swing
Initial ContactInitial Contact
FootFootsupinatedsupinated
AnkleAnkleNeutral or dorsiflexedNeutral or dorsiflexed
KneeKneeNeutral or slightly Neutral or slightly flexedflexed
HipHipFlexed 20Flexed 20--3030°°
Loading ResponseLoading Response
FootFootPronation beginning:Pronation beginning:
Talus slides anterior/flexes/evertsTalus slides anterior/flexes/evertsCalcaneal eversion 5Calcaneal eversion 5°°
Both initiate internal rotation of tibiaBoth initiate internal rotation of tibiaPronation 4Pronation 4--1212°°
AnkleAnkle
PCG
Plantar flexion to 5Plantar flexion to 5--10 10 °°Ankle rockerAnkle rocker
Eccentric contraction of anterior Eccentric contraction of anterior compartmentcompartment
Absorb shock/ limit stress to plantar Absorb shock/ limit stress to plantar tissuestissues
KneeKneeFlexion to 20Flexion to 20°°
Eccentric contraction of quadricepsEccentric contraction of quadricepsHipHip
Begins to extendBegins to extend
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Pronation as a shock absorberPronation as a shock absorber
Talus adducts and plantar flexesTalus adducts and plantar flexesLowers ankle mortiseLowers ankle mortiseInternally rotates kneeInternally rotates kneeIncreases subtalar joint ROMIncreases subtalar joint ROMIncreases subtalar joint ROMIncreases subtalar joint ROM
Pronation as a shock absorberPronation as a shock absorberLowers ankle mortiseLowers ankle mortise
Allows muscles to absorb force over a longer time Allows muscles to absorb force over a longer time frameframe
Pronation as a shock absorberPronation as a shock absorber
Internally rotates kneeInternally rotates kneeAllows knee to flexAllows knee to flexQuads dampen action eccentricallyQuads dampen action eccentrically
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Pronation as a shock absorberPronation as a shock absorber
Increases range of subtalar motionIncreases range of subtalar motionTalonavicular and calcaneocuboid axes Talonavicular and calcaneocuboid axes parallelparallel
The 3 RockersThe 3 Rockers
heel rockerheel rocker: the heel is the fulcrum as the foot rolls into plantar flexion. The : the heel is the fulcrum as the foot rolls into plantar flexion. The pretibial muscles eccentrically contract to decelerate the foot drop and pull pretibial muscles eccentrically contract to decelerate the foot drop and pull the tibia forwardthe tibia forwardankle rockerankle rocker: the ankle is the fulcrum and the tibia roll forward due to : the ankle is the fulcrum and the tibia roll forward due to forward momentum. The soleus eccentrically contracts to decelerate the forward momentum. The soleus eccentrically contracts to decelerate the forward progressionforward progressionforefoot rockerforefoot rocker: tibial progression continues and the gastroc/soleus groups : tibial progression continues and the gastroc/soleus groups contract to decelerate the rate of forward limb movement. This, along with contract to decelerate the rate of forward limb movement. This, along with forward momentum, passive tension in the posterior compartment muscles, forward momentum, passive tension in the posterior compartment muscles, and windlass effect of the plantar fascia results in heel lift. and windlass effect of the plantar fascia results in heel lift.
Heel rocker revisitedHeel rocker revisited
Tibialis anterior dorsiflexes and inverts Tibialis anterior dorsiflexes and inverts EDL and peroneus tertius dorsiflexes and EDL and peroneus tertius dorsiflexes and evertsevertsB th h l t i t i idt l j i tB th h l t i t i idt l j i tBoth help to maintain midtarsal joint Both help to maintain midtarsal joint pronated about oblique axispronated about oblique axisFoot strikes in 8Foot strikes in 8°° inversion and is brought inversion and is brought to ground through continued subtalar to ground through continued subtalar pronationpronation
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Heel rocker revisitedHeel rocker revisited
Tibialis anterior Tibialis anterior dorsiflexes and dorsiflexes and inverts inverts
Tibialis Anterior VideoTibialis Anterior VideoTibialis Anterior VideoTibialis Anterior Video
Heel rocker revisitedHeel rocker revisitedEDL and peroneus tertius dorsiflexes and evertsEDL and peroneus tertius dorsiflexes and everts
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Heel rocker revisitedHeel rocker revisitedBoth help to maintain midtarsal joint Both help to maintain midtarsal joint pronated about oblique axispronated about oblique axis
PCG
Heel rocker revisitedHeel rocker revisited
Foot strikes in 8Foot strikes in 8°° inversion and is brought inversion and is brought to ground through continued subtalar to ground through continued subtalar pronationpronation
Rockers VideoRockers VideoRockers VideoRockers Video
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Polling Question 1Polling Question 1Polling Question 1Polling Question 1
midstancemidstanceFootFoot
Subtalar joint fully Subtalar joint fully pronatedpronated
AnkleAnkleNeutralNeutralNeutralNeutralAnkle rockerAnkle rocker
KneeKnee1010°° flexionflexion
HipHipneutralneutral
Terminal stanceTerminal stance
FootFootSubtalar joint supinates to neutralSubtalar joint supinates to neutral
AnkleAnkle55°° d ifl dd ifl d55°° dorsiflexeddorsiflexed
KneeKneeNear full extensionNear full extension
HipHipExtended 10 Extended 10 °°
Actually pre swing
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Terminal stanceTerminal stanceFootFoot
Subtalar joint supinates to neutralSubtalar joint supinates to neutralSwing phase of opposite leg assists in Swing phase of opposite leg assists in supinationsupination
Calcaneocuboid locking mechanismCalcaneocuboid locking mechanism
Locks lateral columnLocks lateral columnMinimizes muscular strainMinimizes muscular strain
Muscles insufficient to perform job on their ownMuscles insufficient to perform job on their ownS l h l t i t i thi d i l iS l h l t i t i thi d i l iSoleus helps to maintain this during propulsionSoleus helps to maintain this during propulsion
Plantar flexes ankle and inverts subtalar jointPlantar flexes ankle and inverts subtalar jointThis allows dorsiflexion of 4This allows dorsiflexion of 4thth and 5and 5thth metatarsals and metatarsals and locks locks lateral columnlateral column
Assisted by peroneus longus/brevis Assisted by peroneus longus/brevis
Calcaneo cuboid locking mechanism Calcaneo cuboid locking mechanism and peroneus brevis and longusand peroneus brevis and longus
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Peroneus longus function and Peroneus longus function and subtalar joint positionsubtalar joint position
lateral medial
Medial cunieform
Cuboid
Force lateral
Abducts forefoot
Force equal Force downward
Determining the calcaneocuboid Determining the calcaneocuboid locking mechanismlocking mechanism
this simulates ground reactive forcesthis simulates ground reactive forces
Ankle dorsiflexionAnkle dorsiflexion
Gaps and deepens distal tib/fib jointGaps and deepens distal tib/fib jointFibula drops inferior and externally rotates Fibula drops inferior and externally rotates to deepen mortiseto deepen mortise
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preswingpreswingPropulsionPropulsionHeel lift and toe offHeel lift and toe offForefoot rockerForefoot rocker
PCG
4 factors causing heel lift4 factors causing heel lift
Forward momentum of torsoForward momentum of torsoMoves center of mass forwardMoves center of mass forward
Contraction of soleus and deep mmContraction of soleus and deep mmD l t f d t f tibiD l t f d t f tibiDecelerates forward momentum of tibiaDecelerates forward momentum of tibia
Contraction of gastroc Contraction of gastroc Flexes knee and plantarflexes ankleFlexes knee and plantarflexes ankle
Increased tension in plantar fasciaIncreased tension in plantar fasciaWindlass effectWindlass effect
4 factors of Heel lift4 factors of Heel lift
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Heel rise videosHeel rise videosHeel rise videosHeel rise videos
Peroneus Longus FunctionPeroneus Longus FunctionAnkle plantar Ankle plantar flexion decreases flexion decreases action of soleusaction of soleusPeroneus longus Peroneus longus dorsiflexes anddorsiflexes anddorsiflexes and dorsiflexes and everts cuboid, everts cuboid, locking lateral locking lateral columncolumn
Helps to maintain Helps to maintain 11stst met contact met contact with groundwith ground
Peroneus Longus FunctionPeroneus Longus FunctionPeroneus Peroneus longus longus dorsiflexes and dorsiflexes and everts cuboid, everts cuboid, l ki l t ll ki l t llocking lateral locking lateral columncolumn
Helps to Helps to maintain 1maintain 1stst met met contact with contact with groundground
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Peroneus videoPeroneus videoPeroneus videoPeroneus video
Polling question 2Polling question 2Polling question 2Polling question 2
initial swinginitial swing
Contraction of mm. to Contraction of mm. to assist in ground assist in ground clearance of foot in clearance of foot in midswingmidswingmidswingmidswing
ankle dorsiflexors, ankle dorsiflexors, knee flexors, and hip knee flexors, and hip flexorsflexors
Acceleration of limbAcceleration of limb
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midswingmidswing
Largely passiveLargely passiveSustained by inertia Sustained by inertia of limbof limb
Terminal swingTerminal swing
Deceleration of limbDeceleration of limbFlexion of hipFlexion of hipExtension of kneeExtension of kneeDorsiflexion of ankleDorsiflexion of ankleInversion of footInversion of foot
BrainFBrainFull?ull?ull?ull?
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Running Stride EvaluationRunning Stride Evaluation
Running stride can be divided into a Running stride can be divided into a support or contact phase support or contact phase ((~40%)~40%) and and recovery phaserecovery phase ((~60%)~60%)
similar to stance and swingsimilar to stance and swing
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The The support or contact phasesupport or contact phase can be divided can be divided into 3 parts:into 3 parts:
Foot stanceFoot stance: weight acceptance by the supporting : weight acceptance by the supporting limblimbMid supportMid support: support as the body passes over the : support as the body passes over the weight bearing extremityweight bearing extremityToe offToe off: the beginning of propulsion: the beginning of propulsion
Support /Recovery videoSupport /Recovery videoSupport /Recovery videoSupport /Recovery video
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Polling question 3Polling question 3Polling question 3Polling question 3
Foot stanceFoot stanceSimilar to Similar to wt acceptance wt acceptance and loading responseand loading responseActions must occur Actions must occur quicker!quicker!
Foot must initiateFoot must initiateFoot must initiate Foot must initiate pronation to absorb pronation to absorb shockshockKnee flexes to absorb Knee flexes to absorb shockshockFoot mechanics depend Foot mechanics depend on area of strikeon area of strike
Muscles active at foot stanceMuscles active at foot stanceTA, EDL, EHL, Peroneus TertiusTA, EDL, EHL, Peroneus Tertius
Eccentric lowering of footEccentric lowering of footTP, FDL, FHLTP, FDL, FHL
To slow pronationTo slow pronationQuadracepsQuadraceps
Eccentric flexion of kneeEccentric flexion of kneePopliteusPopliteus
Assists pclAssists pclHamstringHamstringHamstringHamstring
Decelerates legDecelerates legTFLTFL
Counterbalances glutealsCounterbalances glutealsGlutealsGluteals
Decelerates legDecelerates legIliocostalisIliocostalis
Maintains frontal stabilityMaintains frontal stabilityContracts to decelerate leg if gluts Contracts to decelerate leg if gluts not activenot active
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midsupportmidsupportAnalogous to Analogous to midstancemidstanceFoot in maximal pronationFoot in maximal pronation
Muscles active at mid supportMuscles active at mid supportAnterior compartmentAnterior compartment
Quiescent in walking gaitQuiescent in walking gaitRunning: to Running: to accelerateaccelerate anterior anterior translation of tibiatranslation of tibia
TP, FDL, FHLTP, FDL, FHLTo To deceleratedecelerate pronation pronation
Peroneus longus/brevisPeroneus longus/brevisDeceleratesDecelerates supination at endsupination at endStabilizes midfoot Stabilizes midfoot
PopliteusPopliteusAssists gastroc/soleus to decrease Assists gastroc/soleus to decrease knee extensionknee extension
Gastroc/soleusGastroc/soleusDecelerates knee extension and Decelerates knee extension and anterior translation of tibiaanterior translation of tibiaDecelerate internal rotation of femur Decelerate internal rotation of femur and tibiaand tibia
HamstringHamstringDecelerate/accelerate Decelerate/accelerate
QuadracepQuadracepStabilize kneeStabilize knee
Toe offToe offAnalogous to Analogous to terminal stance and terminal stance and pre swingpre swingFoot must supinate Foot must supinate to provide a rigid to provide a rigid leverlever
Aided by Aided by contralateral limbcontralateral limb
Propulsion from Propulsion from posterior posterior compartment compartment and/or momentumand/or momentum
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Muscles active at toe offMuscles active at toe offFHL/abductor/adductor hallicusFHL/abductor/adductor hallicus
Stabilizes hallux for propulsionStabilizes hallux for propulsionPeroneus longus/brevisPeroneus longus/brevis
Calcanoecuboid locking mechanismCalcanoecuboid locking mechanismPlantar flexes 1Plantar flexes 1stst ray and improves ground ray and improves ground contactcontact
TP, FHL, FDLTP, FHL, FDLMaintain digits against groundMaintain digits against groundDecelerate forward movement of tibiaDecelerate forward movement of tibiaHelps supinate subtalar jointHelps supinate subtalar joint
Gastroc/soleusGastroc/soleusGastroc/soleusGastroc/soleusKnee flexion, heel liftKnee flexion, heel liftSoleus helps to supinate subtalar joint and Soleus helps to supinate subtalar joint and stabilize lateral columnstabilize lateral column
TA, EHL, EDL, PTTA, EHL, EDL, PTAssist in ankle dorsiflexion and maintaining Assist in ankle dorsiflexion and maintaining 11stst met in contact with groundmet in contact with groundKeep toes from clawingKeep toes from clawing
PopliteusPopliteusExternally rotates femur > tibiaExternally rotates femur > tibia
Quadracep/psoas/TFLQuadracep/psoas/TFLTo help initiate hip flexionTo help initiate hip flexion
Hamstrings?Hamstrings?Knee flexion and propulsion?Knee flexion and propulsion?
High and low gear push offHigh and low gear push off
Support PhaseSupport Phase
Foot stanceFoot stanceMid supportMid supportToe offToe off
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Slo mo ap videoSlo mo ap videoSlo mo ap videoSlo mo ap video
The The recovery phaserecovery phase can be divided into 3 phases:can be divided into 3 phases:Follow throughFollow through: bringing the toe off foot off the ground into : bringing the toe off foot off the ground into extensionextensionForward swingForward swing: moving the limb forward, past midline and : moving the limb forward, past midline and preparing for descentpreparing for descentFoot descentFoot descent: the limb descending and preparing for : the limb descending and preparing for ground contact.ground contact.
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Recovery Phase: Follow throughRecovery Phase: Follow throughAcceleration of limbAcceleration of limb
Obliques, iliocostalis, Obliques, iliocostalis, TFL, psoas, sartoriusTFL, psoas, sartorius
Dorsiflexion of ankleDorsiflexion of ankleTA EHL EDL PTTA EHL EDL PTTA, EHL, EDL, PTTA, EHL, EDL, PT
Flexion of kneeFlexion of kneeSustained from toe offSustained from toe off
Flexion of thighFlexion of thighSustained from toe offSustained from toe off
Recovery Phase: Forward swingRecovery Phase: Forward swing
Similar to midswingSimilar to midswingShould be largely passive Should be largely passive
Recovery Phase: Foot DescentRecovery Phase: Foot Descent
Similar to terminal Similar to terminal swingswingDeceleration of Deceleration of extremityextremityextremityextremity
Active contraction of Active contraction of gluteals and hamstringsgluteals and hamstringsQuads pre tenseQuads pre tenseAnterior compartmentAnterior compartment
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Recovery PhaseRecovery Phase
Follow throughFollow throughForward swingForward swingFoot descentFoot descent
Recovery videoRecovery videoRecovery videoRecovery video
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Polling question 4Polling question 4Polling question 4Polling question 4
Running Stride Observations: Foot StanceRunning Stride Observations: Foot Stance
StrikeStrikeHeel, Heel, midfoomidfoot, or forefoot?t, or forefoot?
FootFootInverted, everted, pronated, Inverted, everted, pronated, supinatedsupinated??
AnkleAnkleDorsiflexion, Dorsiflexion, neutralneutral or plantar flexion?or plantar flexion?
KneeKneeExtension closed pack, Extension closed pack, extension open packextension open pack, flexion?, flexion?
HipHipFlexionFlexion, neutral, extension?, neutral, extension?
PelvisPelvisPosterior rotationPosterior rotation, neutral, anterior rotation, neutral, anterior rotation
TrunkTrunkNeutralNeutral, flexion, extension?, flexion, extension?
Running Stride Observations: mid supportRunning Stride Observations: mid supportFootFoot
Inverted, everted, Inverted, everted, pronatedpronated, supinated?, supinated?AnkleAnkle
Dorsiflexion, Dorsiflexion, neutralneutral or plantar flexion?or plantar flexion?KneeKnee
Extension closed pack, extension open pack, Extension closed pack, extension open pack, flexionflexion??HipHip
Flexion, Flexion, neutralneutral, extension?, extension?PelvisPelvis
Posterior rotation, Posterior rotation, neutralneutral, anterior rotation, anterior rotationTrunkTrunk
NeutralNeutral, flexion, extension?, flexion, extension?
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Running Stride Observations: Toe offRunning Stride Observations: Toe offFootFoot
InvertedInverted, everted, pronated, , everted, pronated, supinatedsupinated??AnkleAnkle
Dorsiflexion, neutral or Dorsiflexion, neutral or plantar flexionplantar flexion??KneeKnee
Extension closed pack, Extension closed pack, extension open packextension open pack, flexion?, flexion?HipHip
Flexion, neutral, Flexion, neutral, extensionextension??PelvisPelvis
Posterior rotation, neutral, Posterior rotation, neutral, anterior rotationanterior rotationTrunkTrunk
NeutralNeutral, flexion, extension?, flexion, extension?
Consequences of Consequences of pathological gaitpathological gait
Tripod correction videoTripod correction videoTripod correction videoTripod correction video
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Strike patternStrike pattern
Consequences of heel strike gaitConsequences of heel strike gait
Deceleration/accelerationDeceleration/accelerationFull pronation/supination must Full pronation/supination must occuroccurIncreased speed of actionsIncreased speed of actionsppBoth accentuate pathologyBoth accentuate pathology
Overuse of tibialis anteriorOveruse of tibialis anterior
Consequences of midfoot strikeConsequences of midfoot strike
Least amount of stressLeast amount of stressWhen combined with forward leanWhen combined with forward lean
Requires a greater degree of Requires a greater degree of ankle dorsiflexionankle dorsiflexionankle dorsiflexionankle dorsiflexionMay have a difficult time May have a difficult time resupinatingresupinating
Takes more timeTakes more time
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Consequences of forefoot strikeConsequences of forefoot strike
No pronation for shock absorbtionNo pronation for shock absorbtionFoot is in supination = rigidityFoot is in supination = rigidity
Accentuates pathologyAccentuates pathologyU ll t d t i tU ll t d t i tUsually overpronater and cannot resupinate Usually overpronater and cannot resupinate appropriatelyappropriatelyAccentuates transverse plane deformitiesAccentuates transverse plane deformities
Ie. TorsionsIe. Torsions
Usually in sprintersUsually in sprinters
Consequences of foot Consequences of foot strike videostrike videostrike videostrike video
Polling question 5Polling question 5Polling question 5Polling question 5
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Consequences of different foot Consequences of different foot types on running gaittypes on running gait
Rearfoot varusRearfoot varus
Over supinated at toe offOver supinated at toe offExcessive use of peronealsExcessive use of peronealsOverstress of lesser Overstress of lesser metatarsalsmetatarsalsmetatarsalsmetatarsalsDorsflexion of great toeDorsflexion of great toe
Trying to force 1Trying to force 1stst MPJ down MPJ down
Cavo varus videoCavo varus videoCavo varus videoCavo varus video
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Rearfoot valgusRearfoot valgus
Excessive internal rotation of Excessive internal rotation of kinetic chainkinetic chainCollapse of midfootCollapse of midfoot
Poor leverPoor leverO t i 5O t i 5thth ttOverstrain 5Overstrain 5thth metmet
Stress on 5Stress on 5thth during eversionduring eversionOveruse of TP, FHL, FDLOveruse of TP, FHL, FDL
Tries to slow pronationTries to slow pronationPoor usage of TA, Peroneus Poor usage of TA, Peroneus tertiustertius
Due to excessive IR of legDue to excessive IR of legCan’t supinateCan’t supinate
RF valgus videosRF valgus videosRF valgus videosRF valgus videos
Forefoot varusForefoot varusoveruse of FHL in attempt to overuse of FHL in attempt to cause forefoot pronationcause forefoot pronation
Overuse of posterior and ant Overuse of posterior and ant tibialistibialis
Due to internal rotation of LEDue to internal rotation of LEDue to internal rotation of LEDue to internal rotation of LE
Medial collapse of kneeMedial collapse of kneePatelloPatello--femoral problemsfemoral problems
Due to internal rotation of LEDue to internal rotation of LE
Risk for excessive met head Risk for excessive met head pressure due to int rotation and pressure due to int rotation and inversioninversion
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Forefoot varusForefoot varus
ff varus videoff varus videoff varus videoff varus video
Forefoot valgusForefoot valgusFOOT IS POOR LEVER!!!FOOT IS POOR LEVER!!!s/s depend on flexible vs. rigids/s depend on flexible vs. rigidPatellar tracking probsPatellar tracking probs
Due to external rotationDue to external rotationOverdevelopment of VMOOverdevelopment of VMOOveruse of P longus, EHL, Overuse of P longus, EHL, peroneus tertiusperoneus tertius
In attempting to e ert and dorsifleIn attempting to e ert and dorsifleIn attempting to evert and dorsiflexIn attempting to evert and dorsiflexOveruse of TP, TA and peroneus Overuse of TP, TA and peroneus brevisbrevis
In attempt to stabilize lateral columnIn attempt to stabilize lateral columnHigher incidence of plantar fascitisHigher incidence of plantar fascitis
Torque applied to plantar fascia due to Torque applied to plantar fascia due to unequal relationship of forefoot to unequal relationship of forefoot to rearfootrearfoot
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Forefoot valgusForefoot valgus
FF Valgus videoFF Valgus videoFF Valgus videoFF Valgus video
Observations above the footObservations above the foot
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Polling question 6Polling question 6Polling question 6Polling question 6
Body postureBody posture
Forward leanForward leanSide to side motionSide to side motionArm carriageArm carriageArm swingArm swing
Forward leanForward leanLean should come from ankles, not hipsLean should come from ankles, not hipsGot speed?Got speed?
The faster they are running, the further forward they will lean to The faster they are running, the further forward they will lean to move their center of gravity forward. move their center of gravity forward.
People with People with excessive forward leanexcessive forward lean will often have will often have weak gluteals, so they will recruit their hamstrings to “pull weak gluteals, so they will recruit their hamstrings to “pull them along”. them along”.
This will create tight hamstrings along with a lower crossed This will create tight hamstrings along with a lower crossed syndrome. syndrome.
Forward flexion at the waist, (especially when combined Forward flexion at the waist, (especially when combined with a steppage gait) with a steppage gait)
usually indicates tight hip flexors or a tight hip capsule. usually indicates tight hip flexors or a tight hip capsule. May have limited ankle dorsiflexion May have limited ankle dorsiflexion tight thoracolumbar junction or limited thoracic extension tight thoracolumbar junction or limited thoracic extension
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Forward lean videoForward lean videoForward lean videoForward lean video
swayswayThis may indicate an LLDThis may indicate an LLDLimited femoral adduction will also Limited femoral adduction will also promote increased sway. promote increased sway.
k d l t di illk d l t di illweakened gluteus medius will cause sag weakened gluteus medius will cause sag of the pelvis on the affected side, which of the pelvis on the affected side, which may be perceived as sway. may be perceived as sway. May be in compensation to loss of ankle May be in compensation to loss of ankle rockerrocker
Gluteus medius videoGluteus medius videoGluteus medius videoGluteus medius video