Three-dimensional kinematics of the distal forelimb in horses trotting on a treadmill and effects of elevation of heel and toe.

The research explored the three-dimensional movements of horse forelimbs while trotting on a treadmill, with a specific focus on how these movements are affected when heel or toe wedges are employed. The findings could inform better clinical application of hoof balancing in treating injuries.

Study Goals and Methodology

• The objective of this study was to better understand the impact of heel or toe wedges on the three-dimensional (3D) movement of four distinct parts of a horse’s forelimb while trotting on a treadmill. This was of interest due to the incomplete understanding of these dynamics and the inaccurate results produced by in vivo studies using skin markers.
• To do this, the researchers worked with three healthy horses. Ultrasonic markers were surgically attached to the four lower segments of the left forelimb of each horse, allowing the team to track their motion in three dimensions.
• Researchers then recorded the horse’s movements as they trotted on a treadmill and used a joint coordinate system to calculate rotations within the digital joints on the distal forelimb.
• The outcome of the horses trotting with six degree heel or toe wedges was compared to their movement with standard flat shoes.

Key Findings

• The study revealed that horse trotting with heel wedges showed significant increases in maximal flexion and decreases in maximal extension of the proximal (PIPJ) and distal (DIPJ) interphalangeal joints.
• Conversely, with the toe wedges, almost reciprocal effects were observed, save for the maximal extension of the PIPJ.
• In both conditions, there were no significant differences in flexion-extension of the metacarpophalangeal joint or extrasagittal motions of the digital joints.

Conclusions and Clinical Implications

• The research concluded that, at a slow trot on a treadmill, heel and toe wedges do influence the sagittal plane kinematics of the interphalangeal joints.
• The findings present a more detailed understanding of the actual effects of toe and heel wedges on the 3D kinematics of the three digital joints in horse forelimbs.
• This comprehension could improve the clinical usage of sagittal alteration of hoof balance for the treatment of distal forelimb injuries in horses, leading to more effective veterinary treatment and potentially faster recovery times for these animals.