The effect of an acute hoof wall angulation on the stride kinematics of trotting horses.

This research investigates how altering the angle of a horse’s hoof (through farrier work) can impact its stride pattern. Using high-speed cinematography, six horses were studied under two conditions (normal and acute hoof angulation) signifying a change in the angle of the dorsal hoof wall. The study found that with a sharper hoof angle, the horses had fewer heel-first impacts and longer breakover times.

Methodology

• The researchers used high speed cinematography as their main investigative tool, providing a clear and detailed visualisation of the horses’ strides. The experiment was carried out with six sound horses.
• The hoof of each horse was subjected to two different farriery treatments. ‘Normal’ treatment involved aligning the dorsal hoof wall with the pastern axis, while ‘acute’ treatment involved a reduction of the angle by approximately 10 degrees.
• The reduced angle was achieved by allowing the horse’s toes to grow longer relative to the horse’s heels.

Findings

• The results indicated significant differences between the two treatments in terms of how the horses’ hooves impacted the ground and the duration of breakover (the phase when the horse’s foot pivots on its toe as it’s lifted up).
• With the acute angulation, there were fewer heel-first impacts but a greater number of toe-first impacts. These differences were statistically significant.
• The acute angulation also resulted in prolonged breakover time. This was also statistically significant.
• The stride length, duration of the suspension phase of the stride and duration of the stance phases of the fore and hind limbs showed no significant differences between the two farriery treatments.
• The arc of the toe during flight was similar for both hoof angles for the study cases.
• When the horse’s hoof impacted the ground heel-first or flat-footed, the toe was observed to elevate. However, in an instance of a toe-first impact, the hoof smoothly approached the ground at a more acute angle.

Implications and Conclusion

• The study indicates that manipulating the angulation of a horse’s hoof can significantly impact the way the animal walks and runs, notably affecting the hoof-ground impact and breakover duration.
• However, it does not appear to affect stride length or the duration of other stride phases. Therefore, alterations should be carefully considered by veterinarians and farriers, particularly for performance horses.