Related Experiment Video
Updated: Jan 14, 2026
An Inertial Measurement Unit Based Method to Estimate Hip and Knee Joint Kinematics in Team Sport Athletes on the Field
Published on: May 26, 2020
Reliability and predictive validity of trunk and lower extremity kinematics during a jump-landing task using OpenCap
Jeffrey A Turner1, Adam W Kiefer2, Garrett S Bullock3
1Department of Exercise and Sport Science, University of North Carolina at Chapel Hill, NC, USA; STRONG Lab, 711th Human Performance Wing, Air Force Research Laboratory, Wright-Patterson Air Force Base, OH, USA; Department of Orthopaedic Surgery, Wake Forest University School of Medicine, NC, USA.
Markerless motion capture with OpenCap shows good reliability for assessing trunk and lower limb movement during jump landings. This technology can accurately differentiate landing styles, aiding in biomechanical analysis and injury screening.
Area of Science:
- Biomechanics
- Motion Capture Technology
- Human Movement Analysis
Background:
- Markerless motion capture systems are emerging as alternatives to marker-based systems for biomechanical assessments.
- Validation of their measurement properties is crucial for clinical adoption.
Purpose of the Study:
- To evaluate the reliability and predictive validity of the OpenCap markerless motion capture system.
- To assess trunk and lower extremity joint angles during a jump-landing task.
Main Methods:
- Thirty-three healthy individuals performed jump-landing trials across two sessions.
- OpenCap systems captured trunk and lower extremity joint angles.
- Intersystem and test-retest reliability were assessed using ICC and MDC.
- Predictive validity was determined by classifying landing conditions (natural vs. stiff).
Main Results:
- OpenCap demonstrated moderate to excellent intersystem reliability (ICC: 0.79-1.00) and test-retest reliability (ICC: 0.70-0.97).
- Minimal detectable changes ranged from 1.89-11.62 degrees.
- The system accurately distinguished between natural and stiff landings (AUC = 0.92).
Conclusions:
- OpenCap offers reliable and valid measurements of joint angles during jump landings.
- This markerless system provides an accessible and efficient tool for movement assessment, injury screening, and rehabilitation monitoring.
More Related Videos
05:52Lower-Limb Biomechanical Characteristics Associated with Unplanned Gait Termination Under Different Walking Speeds
Published on: August 25, 2020
08:24Sit-to-stand-and-walk from 120% Knee Height: A Novel Approach to Assess Dynamic Postural Control Independent of Lead-limb
Published on: August 30, 2016