A closed-loop cadaveric foot and ankle loading model

Area of Science:

• Biomechanics
• Orthopedics
• Human Motion Analysis

Background:

• Cadaver experiments are crucial for human foot and ankle biomechanics research.
• Accurate force application is essential for valid biomechanical data.
• Estimating extrinsic foot and ankle muscle forces is challenging.

Purpose of the Study:

• To develop a novel loading model for cadaver foot and ankle biomechanics.
• To determine Achilles and posterior tibialis muscle forces experimentally without predetermined values.
• To investigate the model's performance during a specific gait cycle event.

Main Methods:

• Developed a loading model using independent plantarflexion and inversion angle feedback control.
• Specified input parameters: calcaneus position, ground reaction forces, and peroneus forces.
• Simulated in vitro using closed-loop feedback control with human motion analysis data.

Main Results:

• The novel model determined muscle forces experimentally.
• Achilles and posterior tibialis forces were greater using position feedback control compared to traditional estimates.
• Dependent parameters included joint motion and spring ligament strain.

Conclusions:

• The developed model offers a more accurate method for assessing foot and ankle muscle forces in biomechanical studies.
• Experimental determination of muscle forces provides superior data compared to estimations based on physiological cross-sectional area and EMG.
• This approach enhances the validity of cadaver experiments in foot and ankle biomechanics.