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Updated: Jul 1, 2026
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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
Inertial measurement units are comparable to motion capture for measuring intersegmental spinal angular velocities in
Tena Ursini1, Hilary Clayton2, David Levine3
1Department of Large Animal Clinical Sciences, College of Veterinary Medicine, Equine Performance and Rehabilitation Center, University of Tennessee, Knoxville, TN.
American Journal of Veterinary Research
|June 29, 2026
Summary
Inertial measurement units (IMUs) offer a reliable method for measuring equine spinal motion, closely matching traditional motion-capture systems for clinical use.
Area of Science:
- Equine biomechanics
- Motion analysis technology
- Veterinary orthopedics
Background:
- Marker-based motion capture is the gold standard for equine spinal motion analysis.
- Inertial measurement units (IMUs) offer a potential portable and cost-effective alternative.
- Validation of IMU accuracy against established systems is crucial for clinical adoption.
Purpose of the Study:
- To compare the accuracy of IMU-derived intersegmental spinal motion data with marker-based motion capture in horses.
- To assess the agreement between IMU and marker-based systems across multiple planes of motion.
Main Methods:
- Four horses were fitted with synchronized IMUs and marker clusters on custom mounts.
- Intersegmental angular velocities were recorded across 37 gait cycles.
- Bland-Altman analysis and intraclass correlation coefficients (ICCs) were used to evaluate agreement.
Main Results:
- No significant systematic bias was found between IMU and marker-based measurements.
- Excellent agreement (ICC > 0.96) was observed in 7 out of 9 comparisons.
- Good agreement (ICC > 0.85) was found in the remaining 2 comparisons.
Conclusions:
- IMUs provide a valid and accurate method for measuring equine intersegmental spinal angular velocities.
- The high agreement supports the use of IMUs for assessing equine topline function in real-world clinical settings.
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