Morphovolumetric Analysis of the Hoof in Standardbred Horses

Hoof conformation has been linked to catastrophic musculoskeletal injuries. Previous studies have been focused on two-dimensional measurements, thus existing knowledge on three-dimensional hoof analysis is very limited. The objective of this study was to examine the morphogeometric properties of the equine hoof using magnetic resonance imaging technology and provide a benchmark for volumetric internal and external anatomy of the hoof and to investigate the correlation between those measurements. Eighteen horses (5.8 ± 2.6 years) with no known hoof pathologies had undergone magnetic resonance imaging; transverse and mid-sagittal (T1-weighted) images were analyzed. Calibrated digital conformational pictures were also taken. In total, 14 internal and 18 external anatomy measurements were performed using Image J software. Patterns of pairwise correlations were found, that is, the distal phalanx volume was correlated with its width (r = 0.739), but not its length. Digital cushion volume was correlated with its length (r = 0.802). Navicular bone width was correlated with distal phalanx width (r = 0.710), but not deep digital flexor tendon width (r = 0.541). The distal phalanx volume and total hoof volume were correlated with the weight of the horse. Our results provide valuable linear and volumetric data for three-dimensional hoof anatomy and provide valuable information for clinicians and researchers to better identify internal hoof anatomy and differentiate pathological cases.