Distal limb cryotherapy for the prevention of acute laminitis

Abstract

Acute laminitis can be a devastating consequence of systemic diseases such as severe colitis, proximal enteritis and metritis. Prophylactic therapies based on enhancing digital perfusion during the developmental phase of laminitis have resulted in only limited efficacy. Recent insights into the pathophysiology of acute laminitis have lead to the evaluation of cryotherapy for prevention of the disease. Experimental evidence demonstrates that the equine digit is particularly resilient with respect to the potentially detrimental effects of prolonged, extreme cold. Continuous distal limb cryotherapy during the developmental phase was effective in markedly reducing the severity of laminitis in an experimental model, and limited preliminary data suggests a similar effect in clinical cases of colitis. The mechanisms by which cryotherapy may prevent laminitis are unclear. Potent vasoconstriction of the digital circulation could prevent the delivery of systemic “trigger factors” to the digit. A cold-induced potent hypometabolic state within the laminar tissue may protect the laminae from damage regardless of the pathophysiological insult. The authors advocate the continuous application of cryotherapy to the distal limbs of clinical cases that are at high risk of developing acute laminitis. There is currently no evidence to support the use of cryotherapy in horses with preexisting acute laminitis.