A horse may be at risk for developing laminitis due to many causes including colitis or other intestinal disease, grain overload, pleuropneumonia and retained placenta.

Cooling the lower limbs and feet (cryotherapy) in these at-risk horses may help prevent laminitis, but it must be performed prior to any visible signs of a problem.

Cold is thought to act by reducing enzymatic activity in the laminar tissue of the foot, thereby reducing some of the destructive processes that take place in laminitis. Cold has an anti-inflammatory effect, causes vasoconstriction (narrowing of blood vessels), provides pain relief, and lowers the metabolism of the tissues.

However, keeping a horse's feet consistently cold is extremely labor-intensive. It requires immersing a horse’s feet in freezing water for a minimum of 72 hours or during and after a period of risk.

Current research suggests that adequate cooling of the equine foot requires constant cooling of both the hoof and the blood flowing into the hoof (the lower limb, at least as high as the level of the fetlock). The target temperature is quite cold, between 5-10 C (40-50 F), for at least 48 - 72 hours.

Standing a horse in an ice cold stream or the snow sounds good, but these settings are rarely practical.  A horse can stand in tubs of ice-water slush and the ice replaced (around the clock - day and night) as the bath warms, approximately every 1-2 hours. Ice filled rubber boots that enclose the hoof and lower limb are also used, but these too must be regularly replenished with ice to keep the temperature consistently low.

In my experience, current commercial systems (some of which keep the hoof and limb dry) are difficult to maintain and ineffective. Research has shown that many of these systems do not adequately enclose and immerse the hoof and limb and do not reach or maintain the necessary temperature required.

For now, immersion in an ice water slurry that is consistently replenished as the temperature rises appears to be the only reliable means of providing this treatment. Again, this is very labor intensive and may not be possible for some hospitals to achieve.

There has been debate as to whether cold therapy effectively slows laminitis once the signs of laminitis have started. Recent studies suggest that continued application of cold may be helpful in reducing progression of laminitis even after the onset of lameness.

Remember that none of these methods of providing cryotherapy are useful if the horse’s primary disease is not treated aggressively and effectively.