Post on 28-Dec-2015
Predicting future injury in runners using participant-specific models of internal
structural loading
Background
• Incidence of running injury is higho 18.2 – 92.4%
• No decline despite years of research
RecruitmentStrength Testing
MoCap
Surveys
Nexus Visual3D OpenSim
Arnold 2010
Lenhart 2014
MatLab
MatLabor Excel
Analysis
RecruitmentStrength Testing
MoCap
Surveys
Nexus Visual3D OpenSim
Arnold 2010
Lenhart 2014
MatLab
MatLabor Excel
Analysis
Recruitment
• n = 102o >18 yrs. oldo run ≥3 per wk.o no running-related/lower-limb injury within 6 mos.o no other sports at competitive level, or >2 per wk.
RecruitmentStrength Testing
MoCap
Surveys
Nexus Visual3D OpenSim
Arnold 2010
Lenhart 2014
MatLab
MatLabor Excel
Analysis
RecruitmentStrength Testing
MoCap
Surveys
Nexus Visual3D OpenSim
Arnold 2010
Lenhart 2014
MatLab
MatLabor Excel
Analysis
MoCap
• 45-marker set
• 50m indoor track
• 8 Kistler force plateso Embedded in series
• 12 Vicon cameras (T-40, T-160)
• 4 Hyun-Joon laser speed gates
MoCap
• 2 conditionso Constrained
3m/s±5% 5 min. ~18 to 20 laps (~3 to 3.3m/s)
o Typical “Use the pace that you run for the majority of your
mileage” 5 min. ~17 to 26 laps (~2.8 to 4.3m/s)
RecruitmentStrength Testing
MoCap
Surveys
Nexus Visual3D OpenSim
Arnold 2010
Lenhart 2014
MatLab
MatLabor Excel
Analysis
RecruitmentStrength Testing
MoCap
Surveys
Nexus Visual3D OpenSim
Arnold 2010
Lenhart 2014
MatLab
MatLabor Excel
Analysis
Vicon Nexus
• Next steps…o Label datao ~40 trials / participant x 102 participants
~4000 trials
S’up undergrads?
Vicon Nexus
• Next steps…o Label datao ~40 trials / participant x 102 participants
~4000 trialsAuto-labelling?
RecruitmentStrength Testing
MoCap
Surveys
Nexus Visual3D OpenSim
Arnold 2010
Lenhart 2014
MatLab
MatLabor Excel
Analysis
RecruitmentStrength Testing
MoCap
Surveys
Nexus Visual3D OpenSim
Arnold 2010
Lenhart 2014
MatLab
MatLabor Excel
Analysis
Visual3D
• Next steps…o Export labelled datao Correct coordinate systemso Build an Inverse Kinematics modelo Calculate external variables
o joint forces and momentso vGRF, ΔvGRF/to pronationo etc…
RecruitmentStrength Testing
MoCap
Surveys
Nexus Visual3D OpenSim
Arnold 2010
Lenhart 2014
MatLab
MatLabor Excel
Analysis
External variables
RecruitmentStrength Testing
MoCap
Surveys
Nexus Visual3D OpenSim
Arnold 2010
Lenhart 2014
MatLab
MatLabor Excel
Analysis
External variables
Strength testing
• Biodexo Isotonic
Ankle, knee, hip 2 trials: 10°/s “away,” 60°/s “toward” 2 trials: 60°/s “away,” 10°/s “toward”
RecruitmentStrength Testing
MoCap
Surveys
Nexus Visual3D OpenSim
Arnold 2010
Lenhart 2014
MatLab
MatLabor Excel
Analysis
External variables
RecruitmentStrength Testing
MoCap
Surveys
Nexus Visual3D OpenSim
Arnold 2010
Lenhart 2014
MatLab
MatLabor Excel
Analysis
External variables
RecruitmentStrength Testing
MoCap
Surveys
Nexus Visual3D OpenSim
Arnold 2010
Lenhart 2014
MatLab
MatLabor Excel
Analysis
External variables
OpenSim
• Next steps…o Build model…
Arnold et al., 2010 Lenhart et al., 2014 44 muscle lower-limb with patella
o Import… V3D IK models Strength parameters
RecruitmentStrength Testing
MoCap
Surveys
Nexus Visual3D OpenSim
Arnold 2010
Lenhart 2014
MatLab
MatLabor Excel
Analysis
External variables
Internal variables
RecruitmentStrength Testing
MoCap
Surveys
Nexus Visual3D OpenSim
Arnold 2010
Lenhart 2014
MatLab
MatLabor Excel
Analysis
External variables
Internal variables
Surveys• Baseline
o Sexo Experience
years competitive level
o Past habits other PA mileage location warm up
o Footwear shoes orthotics
o Lower-limb and running injury history
Surveys
• 26 weeklyo Other PAo Mileage, time per dayo Changes in footwearo Pain/Injury
Location Pain severity Differential diagnosis Changes in running/PA
RecruitmentStrength Testing
MoCap
Surveys
Nexus Visual3D OpenSim
Arnold 2010
Lenhart 2014
MatLab
MatLabor Excel
Analysis
External variables
Internal variables
RecruitmentStrength Testing
MoCap
Surveys
Nexus Visual3D OpenSim
Arnold 2010
Lenhart 2014
MatLab
MatLabor Excel
Analysis
External variables
Internal variables
RecruitmentStrength Testing
MoCap
Surveys
Nexus Visual3D OpenSim
Arnold 2010
Lenhart 2014
MatLab
MatLabor Excel
Analysis
External variables
Internal variables
Baseline and Prospective variables
RecruitmentStrength Testing
MoCap
Surveys
Nexus Visual3D OpenSim
Arnold 2010
Lenhart 2014
MatLab
MatLabor Excel
Analysis
External variables
Internal variables
Baseline and Prospective variables
Analysis
• Covariates...?
• More complex or hierarchical models…?
• Fitting data to theoretical curve…?