Diagnostic value of 3 new radiographic measurements' ratios in the differentiation of feet with and without laminitis in horses

Abstract

For horses, the foot is an essential organ and damage to its integrity may lead to various pathologies. Laminitis is one of the main pathologies of the foot which may lead to severe pain causing violent lameness and lead to the death of the equine in the most severe cases. Whilst diagnostic techniques continue to evolve, the radiography remains one of the most effective and reliable diagnostic tools. The radiography then appears to be the reference method to diagnosing horses with laminitis. This study aims to investigate the use of 3 ratios of measurement in order to make an accurate diagnosis while overcoming the inaccuracies present when using simple radiographic values in the diagnosis of horses with laminitis. The three ratios studied were : PE/P3 (the founder distance/ the length of the distal phalanx), PS/P3 (the thickness of the sole/ the length of the distal phalanx) and BC/PS (the thickness of the dorsal hoof wall/sole thickness). These three ratios were measured on 31 radiographs of 16 horses with laminitis and on 30 radiographs of 15 non-laminitic horses presented to the University Veterinary Clinic of Liège (CVU of Liège) between 2014 and 2022. These two groups were made up of individuals of different sexes, ages and breeds. The analysis of the measurement ratios and the statistical study showed that the PE/P3 and BC/PS ratios were higher in horses with laminitis than in healthy horses, whereas the PS/P3 ratio was lower in horses with laminitis than in healthy horses. In conclusion, this study demonstrates that there was a significant (at the threshold of 0.05) difference between the PE/P3, PS/P3 and BC/PS ratios to differentiate a horse's foot with laminitis from a horse without laminitis in our sample representing the horses’ population of the CVU of Liege. Moreover, the study of these ratios of radiographic measurements were consistent with the clinical signs and with the main showed radiographic indication. These ratios of radiographic measurement, in parallel with a good clinical examination, may offer a more precise way of diagnosis of this pathology.