Fig. 3. Thoroughbred mare with bilateral sinking and rotation. Pre (A) and post (B) treatment with stem cells, tenotomy, and shoeing.
Intra-arterial and venous regional limb perfusion has been shown to be an effective method of deliv- ering MSC to the digit.18 Intra-arterial perfusion has been shown to result in a more reliable distri- bution to the foot. The venous route was used in most of these cases. It is currently not known when the ideal timing of the first dose should be insti- tuted. Reason would justify that for the benefits during the repair phase of the disease, stem therapy would be most useful before lamellar wedge or epi- dermal cell hyperplasia occurs. This has been shown to take place within the first 30 days of pedal bone displacement.5 In chronic advanced cases with bone disease and lamellar wedge formation,
stem cell therapy had no effect on prognosis. These cases still maintained a thick lamellar wedge, which did not change in appearance on radiographs. In one case, with bone disease and a thick lamellar wedge, the dorsal hoof wall and lamellar wedge was resected prior to stem cell therapy. This was done to strip the unstable tissue in hopes of reseeding the interface with more patent tissue. This case con- tinued to suffer from abscesses, instability, and con- tinued discomfort and was euthanized. There is an intricate relationship between the health of the pa- rietal surface of the pedal bone and the epidermal lamellae, lamellar, and sublamellar dermis.19 This microenvironment has an effect on the regenerative
Fig. 4. Another horse before (A) and 8 months after (B) treatment with stem cells, tenotomy, and shoeing. 502 2014 Vol. 60 AAEP PROCEEDINGS
