In recent studies, researchers have confirmed the benefits of using cryotherapy (cold therapy, or digital hypothermia) to treat acute laminitis. The technique's anti-inflammatory and analgesic effects help prevent the laminar failure (when the laminae anchoring the coffin bone within the hoof fail to support the bone) characteristic of this devastating hoof disease.
But does this mean veterinarians can use cryotherapy to prevent laminitis from developing in at-risk horses in the first place? Susan Holcombe, VMD, MS, PhD, Dipl. ACVS, Dipl. ACVECC, a professor in the Michigan State University (MSU) Department of Large Animal Clinical Sciences, believes so. She presented the results of a recent study she performed on colitis cases at the 2013 International Equine Conference on Laminitis and Diseases of the Foot, held Nov. 1-3 in West Palm Beach, Fla.
Colitis is an infection of the colon that can lead to sepsis-associated laminitis. Holcombe said she has seen many colitis cases come through MSU clinic doors over the years, and often the only thing that prevented her from saving these horses was their development of laminitis.
"We started icing these horses' limbs thanks to the original research of Drs. Chris Pollitt (BVSc, PhD) and Andrew van Eps (BVSc, PhD, MACVSc, Dipl. ACVIM)," she explained. "It seemed to help, but does it prevent laminitis in horses at risk of sepsis-associated laminitis? Our aim was to determine the effect of ice on the development of laminitis in horses diagnosed with colitis."
In her retrospective study, Holcombe and colleagues reviewed the medical records of 130 horses admitted to either MSU (82) or Ohio State University (48) for colitis with evidence of a systemic inflammatory response between 2002 and 2012. She said they excluded horses younger than 2, ponies and draft breeds, and horses previously or currently diagnosed with laminitis. The study horses had either received cryotherapy constantly for at least 48 hours (69 horses) or not at all (61). In reviewing these cases the researchers determined that:
- 27 of the 130 horses (21%) ultimately developed laminitis;
- 20 of the 61 horses (33%) not treated with ice developed laminitis;
- Seven of the 69 horses (10%) treated preventively with ice developed laminitis;
- Laminitis incidence was significantly higher in more compromised horses; and
- There was a positive association between Potomac horse fever (PHF, a type of infectious colitis) cases and laminitis development, indicating horses with PHF are at particularly high risk for laminitis.
"Horses receiving prophylactic (preventive) ice were 10 times less likely to develop laminitis than horses that did not receive ice," Holcombe summarized.
She said the advantages of using cryotherapy include not only the compelling study results on its efficacy, but also its safety for the horse. Disadvantages are that it restricts the horse's movement and is very labor-intensive (and, thus, more expensive for the owner). Still, Holcombe said, she and her fellow clinicians at MSU now make it standard practice to ice all four feet of horses diagnosed with colitis, as well as many horses post-colic surgery, for 24 hours after clinical signs of sepsis have resolved to help prevent laminitis.
The study, “Prophylactic digital cryotherapy was associated with decreased incidence of laminitis in horses diagnosed with colitis," was published online in the August 2013 issue of the Equine Veterinary Journal.
Disclaimer: Seek the advice of a qualified veterinarian before proceeding with any diagnosis, treatment, or therapy.