Video Observational Gait Video Observational Gait Analysis Analysis

on 5 Dollars a Dayon 5 Dollars a DayDavid Webner, MDDavid Webner, MDAssociate DirectorAssociate Director

Sports Medicine FellowshipSports Medicine FellowshipCrozer-Keystone Health SystemCrozer-Keystone Health System

Suburban PhiladelphiaSuburban Philadelphia

ReferencesReferences Switaj TL and O’Connor FGSwitaj TL and O’Connor FG: Gait analysis. In Seidenburg PH and : Gait analysis. In Seidenburg PH and

Beutler AI (eds.): Beutler AI (eds.): The Sports Medicine Resource ManualThe Sports Medicine Resource Manual. . Philadelphia, Saunders, 2008, pp. 537-42.Philadelphia, Saunders, 2008, pp. 537-42.

O’Connor FG, Hoke B, and Torrance AO’Connor FG, Hoke B, and Torrance A: Video gait analysis. In : Video gait analysis. In O’Connor FG, Wilder RP (eds.): O’Connor FG, Wilder RP (eds.): Textbook of Running MedicineTextbook of Running Medicine. New . New York, McGraw-Hill, 2001, pp. 59-66.York, McGraw-Hill, 2001, pp. 59-66.

James SL and Jones DCJames SL and Jones DC: Biomechanical aspects of distance running : Biomechanical aspects of distance running injuries. In Cavanagh (ed.), injuries. In Cavanagh (ed.), Biomechanics of Distance RunningBiomechanics of Distance Running, , Champaign, Ill, Human Kinetics, 1990, pp. 249-69.Champaign, Ill, Human Kinetics, 1990, pp. 249-69.

Novachek TFNovachek TF: The biomechanics of running and sprinting. In Guten : The biomechanics of running and sprinting. In Guten GN (ed.): GN (ed.): Running InjuriesRunning Injuries. Philadelphia, Saunders, 1997, pp. 4-19.. Philadelphia, Saunders, 1997, pp. 4-19.

Edington CJ, Frederick EC, Cavanagh PREdington CJ, Frederick EC, Cavanagh PR: Rearfoot motion in : Rearfoot motion in distance running. In Cavanagh PR (ed.): distance running. In Cavanagh PR (ed.): Biomechanics of Distance Biomechanics of Distance RunningRunning, Champaign, Ill, Human Kinetics, 1990, pp. 135-64., Champaign, Ill, Human Kinetics, 1990, pp. 135-64.

Milliron MJ and Cavanagh PRMilliron MJ and Cavanagh PR: Sagittal plane kinematics of the : Sagittal plane kinematics of the lower extremity during distance running, in Cavanagh PR (ed.): lower extremity during distance running, in Cavanagh PR (ed.): Biomechanics of Distance RunningBiomechanics of Distance Running, Champaign, Ill, Human , Champaign, Ill, Human Kinetics, 1990, pp. 65-105Kinetics, 1990, pp. 65-105

OutlineOutline BackgroundBackground RecommendationsRecommendations FundamentalsFundamentals ProcedureProcedure

– EquipmentEquipment– DocumentationDocumentation

AnalysisAnalysis ExamplesExamples

BackgroundBackground HistoryHistory

– Initially performed by running coaches Initially performed by running coaches in the early 1900sin the early 1900s

– Reliability increases with experienceReliability increases with experience– TechnologyTechnology

Video-assisted frame by frameVideo-assisted frame by frame Allows evaluation of non-elite athleteAllows evaluation of non-elite athlete

BackgroundBackground ResearchResearch

– Predominantly in physical therapyPredominantly in physical therapy Rehab patients from CVARehab patients from CVA Children with gait abnormalitiesChildren with gait abnormalities

– CP, neuromuscular diseaseCP, neuromuscular disease– No evidence-based research correlating No evidence-based research correlating

injury with modifications in gait analysisinjury with modifications in gait analysis Athlete variabilityAthlete variability Interobserver variabilityInterobserver variability

RecommendationsRecommendations Evaluation of subtle Evaluation of subtle

gait changes not gait changes not detectable in static detectable in static examinationexamination

Orthotic evaluationOrthotic evaluation Gait refinement with Gait refinement with

limb prostheseslimb prostheses Physical therapyPhysical therapy Chronic exertional Chronic exertional

compartment compartment syndrome testingsyndrome testing

Fundamentals – Gait CycleFundamentals – Gait Cycle Stance phase (IC Stance phase (IC

TO)TO)– Loading responseLoading response– MidstanceMidstance– Terminal stanceTerminal stance– PreswingPreswing

Swing phase (TO Swing phase (TO IC)IC)– Initial swingInitial swing– MidswingMidswing– Terminal swingTerminal swing

Fundamentals -- Gait CycleFundamentals -- Gait Cycle WalkingWalking

– Stance 60%Stance 60%– Swing 40%Swing 40%– Double supportDouble support

RunningRunning– Stance 40%Stance 40%

Absorption and Absorption and propulsionpropulsion

– Swing 60%Swing 60% Initial and terminal Initial and terminal

– Double floatDouble float

Fundamentals -- DefinitionsFundamentals -- Definitions Stride length:Stride length:

– Initial contact of one foot to the otherInitial contact of one foot to the other Depends on height, leg length, skillDepends on height, leg length, skill

Step length:Step length:– One complete gait cycleOne complete gait cycle

Cadence:Cadence:– Number of steps for any given timeNumber of steps for any given time

Women (6-9 steps/min) > menWomen (6-9 steps/min) > men Increased speed:Increased speed:

– Step length and cadence increaseStep length and cadence increase

Fundamentals -- PhysicsFundamentals -- Physics KinematicsKinematics

– Range of motion of Range of motion of body segments body segments involved in an involved in an activityactivity

– Usually spoken Usually spoken about in the sagittal about in the sagittal planeplane

KineticsKinetics– Measure of the Measure of the

forces that are forces that are responsible for that responsible for that activityactivity

– Vertical forces Vertical forces increase from increase from walking to running walking to running (1.5 times body (1.5 times body weight 4 times body weight 4 times body weight)weight)

Fundamentals -- RunningFundamentals -- Running Increased speed leads to increased Increased speed leads to increased

anglesangles– Hips and knees: increased flexionHips and knees: increased flexion– Increased ankle dorsiflexionIncreased ankle dorsiflexion

Responsible for lowering the center of Responsible for lowering the center of gravitygravity

PhasePhase JointJoint ROMROM

Foot strike to midstanceFoot strike to midstance HipHipKneeKneeAnkleAnkle

3232° flex midstance° flex midstance3030° flex midstance° flex midstance 7° dorsiflexion *7° dorsiflexion *

Midstance to Midstance to take-offtake-off

HipHipKneeKneeAnkleAnkle

77° flex * ° flex * 27° flex27° flex15° dorsiflexion15° dorsiflexion

Follow throughFollow through HipHipKneeKneeAnkleAnkle

1212° extension° extension10° flexion10° flexion25° plantarflexion25° plantarflexion

Forward swingForward swing HipHipKneeKneeAnkleAnkle

4242° flexion° flexion65° flexion65° flexion15° plantarflexion15° plantarflexion

Foot descentFoot descent HipHipKneeKneeAnkleAnkle

5252° flexion° flexion75° flexion75° flexionNeutral *Neutral *

McPoil and Cornwall: Applied sports biomechanics in rehabilitation: running. In Zachazeski, MaGee, and Quillen (eds.): Athletic Injuries and Rehabilitation. Philadelphia, Saunders, 1996, p. 356

Range of MotionRange of Motion HipHip

– Increased ROM from walking to runningIncreased ROM from walking to running Increased flexion, and decreased extensionIncreased flexion, and decreased extension Max extension at take off and max flexion at Max extension at take off and max flexion at

terminal swingterminal swing No coronal plane changesNo coronal plane changes

PelvisPelvis– Initial contact: 8Initial contact: 8° internal rotation° internal rotation– Take off: 8° external rotationTake off: 8° external rotation

Range of Motion -- KneeRange of Motion -- Knee WalkingWalking

– Initial contact Initial contact 10° 10° flexflex

– 6060° (64° flex – 8° ° (64° flex – 8° ext)ext)

RunningRunning– Initial contact 35Initial contact 35°°

flexflex– 6363° (79° flex -16° ° (79° flex -16°

ext)ext)– Flexes during Flexes during

absorption phase absorption phase while runningwhile running

– Midstance: reversal Midstance: reversal of motion to enter of motion to enter propulsionpropulsion

Range of Motion -- AnkleRange of Motion -- Ankle WalkingWalking

– 1818° plantarflex to ° plantarflex to 12° dorsiflex = 30° 12° dorsiflex = 30° total total

RunningRunning– Increase to 50Increase to 50° °

totaltotal– Increase in hip and Increase in hip and

knee flexion limit knee flexion limit the plantarflexion the plantarflexion and produce rapid and produce rapid dorsiflexion in dorsiflexion in propulsion propulsion

Range of Motion -- FootRange of Motion -- Foot Triplanar movementTriplanar movement

– Pronation = dorsiflexion + abduction Pronation = dorsiflexion + abduction and eversionand eversion

– Supination = plantarflexion + adduction Supination = plantarflexion + adduction and inversionand inversion

ProcedureProcedure Systematic processSystematic process Prepping the runner Prepping the runner

– 1 L of miralax1 L of miralax– MarkersMarkers

Prepping your equipmentPrepping your equipment– Make sure the camera’s charged!Make sure the camera’s charged!

Physical ExamPhysical Exam– Static stance, shoe wear pattern, upper Static stance, shoe wear pattern, upper

and lower extremity assessmentand lower extremity assessment

ProcedureProcedure Sagittal planeSagittal plane

– Hip, knee and ankle flexion and extensionHip, knee and ankle flexion and extension Coronal planeCoronal plane

– Hip (adduction/abduction)Hip (adduction/abduction)– Knee (varus/valgus)Knee (varus/valgus)– Foot (inversion/eversion)Foot (inversion/eversion)

Special protocolsSpecial protocols– Age, speed, incline etc.Age, speed, incline etc.

2 Hour Gait Analysis2 Hour Gait Analysis Full physical examFull physical exam Static stills shoes off – 4 viewsStatic stills shoes off – 4 views Static stills shoes on – 4 viewsStatic stills shoes on – 4 views Walking shoes off – 4 viewsWalking shoes off – 4 views Walking shoes on – 4 viewsWalking shoes on – 4 views Running shoes off – 4 viewsRunning shoes off – 4 views Running shoes on – 4 viewsRunning shoes on – 4 views Review sessionReview session RecommendationsRecommendations

30 Minute Gait Analysis30 Minute Gait Analysis Modified Hoke/Lefever-Button Modified Hoke/Lefever-Button

protoccolprotoccol– Lateral viewsLateral views

Head to feet (30 sec)Head to feet (30 sec) Hips to feet (30 sec)Hips to feet (30 sec)

– Posterior viewPosterior view Head to feet (30 sec)Head to feet (30 sec) Hips to feet (30 sec)Hips to feet (30 sec) Knee to feet (30 sec)Knee to feet (30 sec)

HardwareHardware Exam roomExam room TreadmillTreadmill

– Important extremes too considerImportant extremes too consider WeightWeight SpeedSpeed InclineIncline

Video cameraVideo camera– Don’t overlook…Don’t overlook…

Power cord, batteries, videotapePower cord, batteries, videotape Television/laptopTelevision/laptop

– Be prepared…Be prepared… Video/audio auxiliary cablesVideo/audio auxiliary cables Remote, playback with pause/slow motion featuresRemote, playback with pause/slow motion features

DocumentationDocumentation HeadHead

– Vertically on shoulders (not to exceed 4 Vertically on shoulders (not to exceed 4 cm)cm)

– No anterior/posterior, lateral rotation or No anterior/posterior, lateral rotation or side bendingside bending

– Linearity from ear to shoulder during the Linearity from ear to shoulder during the entire gait cycleentire gait cycle

ElbowElbow– Normal carry is between 80Normal carry is between 80°-110° flexion°-110° flexion

Possible PathologyPossible Pathology HeadHead

– Abnormalities suggest cervical dysfunction, Abnormalities suggest cervical dysfunction, muscle weakness, or previous cervical traumamuscle weakness, or previous cervical trauma

– Excessive vertical displacement of the head due to Excessive vertical displacement of the head due to leg length discrepancyleg length discrepancy Early heel liftEarly heel lift

– Shoulder Shoulder Abnormal movement may indicate lower extremity injuryAbnormal movement may indicate lower extremity injury

– Arms crossing the midlineArms crossing the midline Possibly indicative of pelvic rotationPossibly indicative of pelvic rotation Wasted running energyWasted running energy

DocumentationDocumentation TrunkTrunk

– Should be linear, without flexion, Should be linear, without flexion, extension or lateral leanextension or lateral lean

Hip/PelvisHip/Pelvis– Pelvic drop should not exceed 4 degreesPelvic drop should not exceed 4 degrees

DocumentationDocumentation KneesKnees

– Cushioning flexion range: position of the Cushioning flexion range: position of the knee at maximum stance flexion minus knee at maximum stance flexion minus position at initial contactposition at initial contact Quadriceps weakness with value less than Quadriceps weakness with value less than

2020°°– Swing phase knee flexion less than 115°Swing phase knee flexion less than 115°

Hamstring weaknessHamstring weakness

DocumentationDocumentation AnkleAnkle

– Increased plantarflexion at foot strikeIncreased plantarflexion at foot strike Anterior tibialis weaknessAnterior tibialis weakness Exertional compartment syndrome (foot drop)Exertional compartment syndrome (foot drop)

– Limited dorsiflexionLimited dorsiflexion Calf tightnessCalf tightness Anterior tibialis impingementAnterior tibialis impingement If combined with early heel off…If combined with early heel off…

– Plantar fasciitis, metatarsalgiaPlantar fasciitis, metatarsalgia

DocumentationDocumentation FootFoot

– Normal motion – subtalar jointNormal motion – subtalar joint Subtalar supination at heel strike, followed Subtalar supination at heel strike, followed

by rotation into pronation up to 8by rotation into pronation up to 8° at the ° at the end of contactend of contact

Repeat supination in midstance, and peaks Repeat supination in midstance, and peaks just before toe off (propulsion)just before toe off (propulsion)

Early pronation during the swing phase and Early pronation during the swing phase and then in neutralthen in neutral

Measuring Subtalar MotionMeasuring Subtalar Motion Normal motionNormal motion

– 66° of inversion at foot strike° of inversion at foot strike– 6-8° of eversion at maximal pronation6-8° of eversion at maximal pronation– Neutral at heel liftNeutral at heel lift– 6-8° of inversion at toe off6-8° of inversion at toe off– Excessive pronation is characterized by Excessive pronation is characterized by

persistent eversionpersistent eversion

Angle of GaitAngle of Gait Posterior viewPosterior view

– Greater than 1.5 inches is too wide-basedGreater than 1.5 inches is too wide-based Can be indicative of IT band syndromeCan be indicative of IT band syndrome

– External rotation of >7External rotation of >7°° Suggests torsional abnormalitiesSuggests torsional abnormalities

– Weak posterior tibial tendon, limited dorsiflexion (?Weak posterior tibial tendon, limited dorsiflexion (?equinus deformity)equinus deformity)

– Calcaneal whipCalcaneal whip Heel rotation on heel riseHeel rotation on heel rise Circumduction – lifting of the affected extremity with Circumduction – lifting of the affected extremity with

rotation could be due to weak anterior tibialis, joint rotation could be due to weak anterior tibialis, joint restriction or weak hip flexorsrestriction or weak hip flexors

Possible PathologyPossible Pathology TrunkTrunk

– Flexion with runningFlexion with running Weak lumbar stabilizersWeak lumbar stabilizers Tight hip flexorsTight hip flexors

– Lateral lean (> 4 cm)Lateral lean (> 4 cm) Leg length discrepancyLeg length discrepancy Hip external rotation / abduction weaknessHip external rotation / abduction weakness

HipsHips– Excessive external rotationExcessive external rotation

Tight hip flexorsTight hip flexors Weak abductors IT Band SyndromeWeak abductors IT Band Syndrome

– Excessive internal rotationExcessive internal rotation PiriformisPiriformis