Heel effects on joint contact force components in the equine digit: a sensitivity analysis

Area of Science:

• Equine biomechanics
• Veterinary orthopedics
• Comparative anatomy

Background:

• Limited research exists on equine distal forelimb joint contact forces related to heel configuration.
• Existing literature primarily focuses on suspensory apparatus tension.

Purpose of the Study:

• To investigate the effect of altered heel height on joint contact forces in the equine coffin and fetlock joints.
• To enhance understanding of digit joint loading during the trot stance phase.

Main Methods:

• Inverse dynamic analysis using kinematic and kinetic data from four Warmblood horses.
• Calculated joint contact forces (CF) and tendon wrapping forces (WF) considering sesamoid bone interactions.
• Sensitivity analysis performed with heel configurations raised by 0°, 6°, and 12°.

Main Results:

• Raising the heel significantly decreased peak coffin joint wrapping forces and contact forces.
• Peak fetlock joint wrapping forces and contact forces increased with heel elevation, though not significantly.
• Deep digital flexor tendon tension decreased, while superficial digital flexor tendon tension increased with heel elevation.

Conclusions:

• Equine coffin and fetlock joint loading are interconnected.
• Heel configuration is a significant factor influencing joint contact forces in the distal forelimb.