breakover | Horse Racing Free Tips

Study: Do Laminitic Horses Move Differently, And If So, How Should We Shoe Them?

German researchers created a study to compare hoof loading patterns of laminitic and sound horses. They used 16 sound horses and ponies as controls, 17 animals that had recently recovered from laminitis and 21 animals that had recovered from laminitis 6 to 12 weeks before.

The scientists placed an instrumented boot on the horses and had them walk across a level, concrete surface with a pressure sensor.

[Story Continues Below]

The sound horses bore the most weight (peak loading) at the toe during mid-stance; the laminitis horses showed peak loading at breakover, when the hoof goes from full loading to leaving the ground. Interestingly, the laminitic group did not show an increase in loading in the heel region; the middle hoof bore most of the weight in loading.

The study team concluded that laminitic horses should be shod with support focused on the middle of the hoof, frog and heel. They should also be shod with the intent to ease breakover, which should reduce loading of the damaged lamellae in the toe.

Elevate Heels To Alleviate Laminitic Pain

Very few equine conditions can be as debilitating as laminitis, which can be triggered by a variety of events or occur on its own. Laminitis occurs when the laminae, a set of finger-like structures which support the coffin bone and hold it in place in the hoof capsule, become inflamed. This inflammation is incredibly painful.

The breakover phase of a horse's stride is the most painful for laminitis horses. This is when all of his weight rests on his toe as he steps forward, putting intense pressure on already-sensitive structures. A study has found that elevating a horse's heels with a wedge can shorten the breakover period, protecting damaged tissues and helping to alleviate some of the horse's pain.

The study used eight acutely laminitic horses to compare the breakover of hooves and those with a heel wedge. The horses were walked on a poured concrete surface both barefoot and with the wedge applied. The scientists found that the heel wedge shortened breakover and reduced the load on the horse's toe. Elevating the heel placed 81 percent of the load on the bottom half of the hoof, near the heel, relieving pain and mitigating lamellar damage.

The researchers recommend using heel wedges for no more than two to three weeks at a time to avoid collapsing the horse's heels and contracting his hooves.

Laminitic Horses May Benefit From Hoof Casts And Heel Wedges

New research from shows that elevating a laminitic horse's heel using a wedge and hoof cast can help alleviate some of the pain associated with the condition.

The breakover phase of a horse's stride is the most painful part for horses suffering from acute laminitis. This is when the heaviest load is placed on the toe and middle region of the hoof. The goal of the new therapy was to try to shift the load from the most-painful area of the hoof onto undamaged areas.

Drs. Al Naem, Lutz-Ferdinand Litzke, Klaus Failing, Johanna Hoffmann, Michael Röcken and Florian Geburek medically treated eight horses with acute laminitis and also applied a hoof cast with a heel wedge.

Measurements were taken with the cast in place and when the cast was removed, when the horse was barefoot. The hoof print was divided into toe, middle hoof and heel region, and measurements were taken that included vertical force, stance duration, contact area while standing, duration of breakover, vertical force on the toe during breakover, and location of the center of force.

The scientists determined that both the vertical force and contact area were higher in the heel region when the horse was wearing both the wedge and the cast, but that decreased once each was removed. The breakover phase lasted just 2 percent of the stance phase when the horse had the cast and wedge in place; it was 6 percent of the stance phase when the horse was barefoot.

The team concluded that heel elevation significantly shortened the breakover phase and decreased the vertical force in the toe region. They suggest that the application of a wedge and a cast to the affected hooves of a horse with laminitis will decreases the stress on the lamellae and reduce pain. The researchers did note that long-term application of a wedge and cast may result in crushed heels, cracks or misplaced bulbs, so they suggest that these tools be limited to two to three weeks of use.

Read the full article here.