Venographic differences in feet of lame vs non-lame horses

ABSTRACT: Understanding vascular occurrences within the hoof has become the focus of scientific work. Venography has begun to be used as a minimally invasive, practical and essential diagnostic method to access digital circulation, with accurate prognostic value. The aim of this study was to evaluate venograms of lame and sound horses, using a semiquantitative scale of radiographic contrast filling, in the following anatomical regions: terminal arch, dorsal laminar vessels to the distal phalanx, coronary plexus, circumflex vessels, and heel bulb. For the venographic study of forelimb hooves, 19 horses (12 males and seven mares), with a mean age of 9.5 ± 4.4 years, were used; 11 animals without clinical signs of lameness (sound) and eight with some degree of claudication (lame), according to the American Association of Equine Practitioners (AAEP). Obtained data were subjected to ANOVA statistical analysis, complemented by the Tukey test, with a significance level of p< 0.05 for comparison between all groups. A difference was observed between venograms of lame and sound horses, regardless of the thoracic limb used for the analysis. Lame animals presented lesser digit perfusion. The decrease in blood circulation was more frequently present in the terminal arch, circumflex vessels, and dorsal laminar vessels. Lame animals with normal or long toe/low heel hoof angles presented higher perfusion scores than clubfoot hoof horses. Despite the hoof angle conformations, digital perfusion was not influenced in sound animals. A larger number of animals should be tested to validate the proposed semiquantitative scale.