Incidence of palmar process fractures of the distal phalanx and association with front hoof conformation in foals

Comparison of Six Different Methods for Measuring the Equine Hoof and Recording of its Three-Dimensional Conformation

Different measuring techniques have been used to objectify the classification of hoof shape. The MicroScribe is a novel tool that might prove useful for measuring hooves without prior reconstruction or compensation of projection artefacts. The aim of this study was to compare biometric data of the equine hoof collected by the MicroScribe tool and measurements collected directly from hooves, scaled photographs and radiographs, from photogrammetry models and computed tomography datasets. The suitability of MicroScribe generated data to differentiate individual hoof conformations was tested. A total of 62 measures were recorded from 16 forehooves. 21 linear and nine angular measures were collected by at least four methods each, and evaluated further by analysis of variance (ANOVA) and multivariate analysis of variance (MANOVA). Ratios and differences of these measures were calculated as suitable for the definition of hoof shapes and analysed as well. Absolute equivalency of methods was detected for five linear and none of the angular measurements. The precision of the tested measurement methods was comparable. In some cases, different methods measure different structures. Radiographs tended to overestimate, while computed tomography slides to underestimate distances. Photogrammetry and scaled photographs were less suitable for measuring hoof angles. The MicroScribe tool can readily be used for hoof measurements. Its values for linear measures showed good equivalency with other methods based on real hooves. For angular measurements, the uneven hoof surface might introduce imprecision. Not all hoof conformations could be detected based on measuring results alone. Diagnosis by a skilled veterinarian is still essential.

Other Clinical Problems of the Equine Foot

Many disorders affect the equine foot, and many hoof problems have multiple predisposing causes. Surgery may be necessary after conservative management has failed. Diseases of the hoof capsule may seem simple, but their effect on performance can be long-lasting and healing is often prolonged. Diagnosis of problems within the hoof capsule is enhanced with the use of computed tomography and MRI. The prognosis of fractures has improved with strategic placement of lag screws across fracture planes using aiming devices and advanced intraoperative imaging techniques. Collaboration between the clinician and a skilled farrier is important for successful management of hoof disorders.

Radiogrametric Analysis of the Thoracic Limb Phalanges in Arabian Horses and Thoroughbred Horses

In this study, it was aimed to determine the statistical differences between Arabian horses and Thoroughbred horses based on X-ray images of forelimb digital bones. Latero-medial X-ray images of digital bones of thoracic limbs were taken of 25 Arabian horses and 50 Thoroughbred healthy horses. The difference between males and females within the breed was statistically analyzed as well. Nine measurements and three indexes taken from phalanges of thoracic limbs were used. Thoroughbred horses did not differ significantly between sexes, as indicated by the ANOVA. For the Arabian horses, the length of the middle of the proximal phalanx (p < 0.05), the length of the middle of the middle phalanx (p < 0.001), and the length of the dorsal surface of the distal phalanx (p < 0.05) measurement points were found to be differentiated between sexes. In the analysis made between Thoroughbred horses and Arabian horses with no respect to sex, the critical measurement was the depth of the caput of the proximal phalanx. The discriminant analysis enabled the correct classification of 89.33% of the proximal phalanx samples to the exact breed. The correct classification rate was 77.33% in the case of middle phalanx and 54.67% in the case of distal phalanx. Measurement results of the distal phalanx were found to be insignificant between both breeds and sexes. The radiological measurements of digital bones showed that sexual dimorphism was not too expressed and that decisive differences were found between the breeds.

EquiSim: An Open-Source Articulatable Statistical Model of the Equine Distal Limb

Most digital models of the equine distal limb that are available in the community are static and/or subject specific; hence, they have limited applications in veterinary research. In this paper, we present an articulatable model of the entire equine distal limb based on statistical shape modeling. The model describes the inter-subject variability in bone geometry while maintaining proper jointspace distances to support model articulation toward different poses. Shape variation modes are explained in terms of common biometrics in order to ease model interpretation from a veterinary point of view. The model is publicly available through a graphical user interface (https://github.com/jvhoutte/equisim) in order to facilitate future digitalization in veterinary research, such as computer-aided designs, three-dimensional printing of bone implants, bone fracture risk assessment through finite element methods, and data registration and segmentation problems for clinical practices.

Correlational Characteristics of Hoof Conformation and Midstance Kinetics at Walk

Variations in hoof conformation may alter stress distribution, thus predisposing horses to pathologies and lameness; however, experimental studies are scarce. Our objective was to investigate the correlation between midstance hoof kinetics at the walk and hoof conformation in horses. Nine clinically sound, unshod horses were walked over a pressure plate, and force (F), contact area (CA), contact pressure (CP), and peak contact pressure (PCP) were recorded at the dorsal, palmar, medial, and lateral regions, as well as for the whole hoof. By using digital radiography and digital pictures, 55 variables of internal and external hoof shape and dimensions of the hoof were measured. Correlations between kinetic and anatomical measurements were investigated using Pearson correlation coefficient. P-values ≤ 0.05 and r values ≥ 0.5 were considered. Several anatomical variables showed correlations with biomechanical variables. Toe angle was negatively correlated with CA (r = -0.72). Several heel height measurements were negatively correlated with dorsal F (-0.59 ≤ r ≤ -0.50), suggesting a trend. Measurements of the dorsal hoof wall thickness and length/width of the distal phalanx showed correlations with F and CP (0.5 ≤ r ≤ 0.71). Our study was focused on midstance biomechanics and at the walk; further investigation on other gaits and parts of the stance phases is warranted. Patterns of correlations between internal structural arrangement and hoof kinetic parameters encourage more research and should be considered by veterinarian and farriers for routine and therapeutic trimming/shoeing.

Foal Fractures: Osteochondral Fragmentation, Proximal Sesamoid Bone Fractures/Sesamoiditis, and Distal Phalanx Fractures

Foals are susceptible to many of the same types of fractures as adult horses, often secondary to external sources of trauma. In addition, some types of fractures are specific to foals and occur routinely in horses under 1 year of age. These foal-specific fractures may be due to the unique musculoskeletal properties of the developing animal and may present with distinct clinical signs. Treatment plans and prognoses are tailored specifically to young animals. Common fractures not affecting the long bones in foals are discussed in this article, including osteochondral fragmentation, proximal sesamoid bone fractures/sesamoiditis, and distal phalanx fractures.

Routine Orthopedic Evaluation in Foals

In order to recognize abnormalities on the physical evaluation, it is mandatory to understand normal developmental variations of the musculoskeletal system. Many abnormalities are self-limiting and, therefore, it is important to recognize which problems require intervention for a successful outcome and which may be complicated by treatment. The importance of a complete and thorough physical evaluation cannot be overemphasized and is the most productive diagnostic tool for recognizing most abnormalities of the skeletal system whether as a component of an after-foaling examination or for lameness or conformation evaluation in foals of all ages.