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Related Experiment Video

Updated: Jan 14, 2026

Subject-specific Musculoskeletal Model for Studying Bone Strain During Dynamic Motion

Subject-specific Musculoskeletal Model for Studying Bone Strain During Dynamic Motion

Published on: April 11, 2018

Muscle Tendon Passive Parameter Estimation Using Musculoskeletal Optimal Control.

Sepehr Ramezani¹, Joseph Dranetz¹, Hwan Choi²

¹Department of Mechanical and Aerospace Engineering, University of Central of Florida, Central Florida Blvd., Orlando, FL, 32816, USA.

Annals of Biomedical Engineering

|October 16, 2025

Summary

A new noninvasive method accurately estimates passive muscle-tendon parameters (PMPs) using optimal control. This approach offers precise biomechanical insights for rehabilitation, sports, and injury prevention.

Keywords:

Lower limb muscles Muscle stiffness Musculoskeletal optimal control Musculotendon passive parameters Tendon stiffness

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Last Updated: Jan 14, 2026

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Area of Science:

Biomechanics
Human Movement Analysis
Musculoskeletal Modeling

Background:

Accurate measurement of passive muscle-tendon parameters (PMPs) is vital for understanding human movement.
Existing methods for PMP measurement are often inconsistent or invasive.

Purpose of the Study:

To develop and validate a novel noninvasive method for estimating PMPs.
To utilize a direct collocated optimal control algorithm for PMP estimation.

Main Methods:

Employed an optimal control algorithm for PMP estimation in silico, mechanical analogues, and in vivo.
Used a quasi-static knee and ankle flexion protocol to isolate passive properties.
Validated the method against experimental data using forward dynamic simulations.

Main Results:

In silico simulations showed <3.5% error for muscle stiffness and tendon slack length, <6% for tendon stiffness.
Mechanical analogue model yielded a maximum 9% error for spring stiffness.
In vivo validation demonstrated average RMSE <0.56° for motion and 0.012 Nm/kg for torque.

Conclusions:

The proposed noninvasive method accurately estimates PMPs in knee flexors/extensors.
This technique provides valuable biomechanical insights.
Potential applications include rehabilitation, sports performance optimization, and injury prevention.