these boots were made for walkin ’ boots were made for walkin ’ the biomechanics of walking in a...
TRANSCRIPT
TheseBootsWereMadeforWalkin’
TheBiomechanicsofWalkinginaFractureBoot
Darlina Liu April21st,2016 BIOL438
FractureBoot=WalkerBoot=CAMWalker
AdjustableInflation Non-inflated RangeofMotion(ROM)
Treatmentfor…• AnkleSprain• StressFracture• DiabeticUlcers• Tendonitis• PlantarFasciitis• Andmore…
WhyStudyThis?• Youwillwalkabout75,000milesinyourlifetime
WhyStudyThis?•Peoplehaveinjuredthemselveswhilewearingaboot
Question
•Howdoeswalkinginafracturebootdifferfromnormalwalking?• Isthefracturebooteffectiveincontrollinganklemotion?•Whataretheeffectsonthesupportingfoot?•Whatarethedifferencesinenergy?
Walking
Walking:StancePhase
AnkleMovement
BonesandMusclesInvolved
Hypothesis
•Predictdecreasedanklerotationforbootfootandincreasedanklerotationforsupportingfootcomparedtonormalwalking
•Predictthatwalkinginfracturebootwillrequiregreaterenergyexpenditurecomparedtonormalwalking
Methods• Filming:SonyCybershot RX10II• DataAnalysis:LoggerProandExcel
MediumLiteVectraWalkerBootfromBregg
ResultsofVideoAnalysis
•AnkleAngle
•StrideLength•KineticEnergy•Velocity
•PotentialEnergy
Video:WalkinginFractureBoot
Video:NormalWalking
AnkleAngleCalculation
70
80
90
100
110
120
130
140
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5
AnkleAn
gle(degrees)
Time(s)
LeftFootAnkleAngle:Bootvs.Normal
Boot Normal
70
80
90
100
110
120
130
140
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5
AnkleAn
gle(degrees)
Time(s)
LeftFootAnkleAngle:Bootvs.Normal
Boot Normal
70
80
90
100
110
120
130
140
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5
AnkleAn
gle(degrees)
Time(s)
RightFootAnkleAngle:Bootvs.Normal
Boot Normal
Boot Normal
AVERAGE(degrees) Left* Right Left Right
MinAnkleAngle 81.1 91.1 78.1 88.2
MaxDorsiflexion 8.9 N/A 11.9 1.8
MaxAnkleAngle 97.6 120.6 107.4 113.0
MaxPlantarflexion 7.6 30.6 17.4 23.0
RangeofMotion 16.5 29.5 29.3 24.8
AnkleComparison
StrideLength•distancecoveredbyinitialcontactofonefootandconsecutivecontactofsamefoot•2MPH=0.894m/s
Boot Normal#ofSteps 6 6
Timeelapsed (s) 4 5Total distancetravelled(m) 3.58 4.47Stridelength (m/step) 0.596 0.745
KineticEnergy=½mv2
• WeightofBoot=1.2lbs =0.54kg• WeightofSneaker=0.4lbs =0.18kg
Boot: Left Normal:Left
Boot:Right Normal:Right
KineticEnergy(J)
1.053 0.325 0.248 0.208
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5
Kine
ticEne
rgy(J)
Time(s)
KineticEnergyComparisonbetweenBootLegandNormalLeg(Left)
Boot Normal
0
0.05
0.1
0.15
0.2
0.25
0.3
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5
Kine
ticEne
rgy(J)
Time(s)
KineticEnergyComparionbetweenSupportingLegandNormalLeg(Right)
Boot Normal
PotentialEnergy=mgh• WeightofBoot=1.2lbs =0.54kg• WeightofSneaker=0.4lbs =0.18kg• g=9.81m/s2
Boot(Left) Normal(Left)
MaximumHeight(m) 0.233 0.324
PotentialEnergy(J) 1.243 0.577
Conclusions& Implications
• Fracturebootdoesstabilizeanklemotionbutitisnotperfect• Thesupportingfootdoesplayacompensatoryrole• Walkinginafracturebootrequiresmoreenergyexpenditure
➤ Rethinkouruseanddesignoffractureboots
Limitations
•Noinjuryattimeoffilming• Limitednumberoftrials• Two-dimensionalvideoanalysis• Treadmilldifferentfromnaturalwalking
NextSteps
•Camerafrommultipleangles•Forcepads•Varyspeedandduration•Examineprotonationoffoot•Analyzewalkinginothertypesofboots
References• TheFrequencyofInjury,MechanismofInjury,andEpidemiologyofAnkleSprains(Garrick1977)• Walking,FootPain,andBiomechanics(http://footactive.co.uk/blog/255-walking-foot-pain-and-biomechanics)• BiomechanicsofFootStrikes&ApplicationsToRunningBarefootorinMinimalFootwear(http://www.barefootrunning.fas.harvard.edu/4BiomechanicsofFootStrike.html)• TheInfluenceofKneePositiononAnkleDorsiflexion(Baumbach etal2014)• Step&StrideLength(http://www.clinicalgaitanalysis.com/teach-in/step/)• WalkingandRunningonTreadmill:TheStandardCriteriaforKinematicStudies(Padulo etal2014)
Thankyou!Anyquestions?