Comparison of the trimming procedure of six different farriers by quantitative evaluation of hoof radiographs

Determination of Positional Parameters of the Distal Phalanx Within the Hoof Capsule in Sound Colombian Paso Horses

The economic relevance, populational importance and expansion of the Colombian Paso Horse to other latitudes calls for a growth in studies based on this type of horse. Lack of written reports about the relationship of the distal phalanx (DP) within the hoof in this gaited horse makes it important to establish a baseline to determine hoof health and possible alterations. The purpose of this study was to report, for the first time, the positional parameters of the distal phalanx, and its relationship within the hoof in sound Colombian Paso Horses. A latero-medial radiographic image of each digit was taken in 45 horses between 3 and 5 years old, distributed into groups according to the gaits determined by FEDEQUINAS. Three angles and three distances were measured. The dorsal wall thickness (W-T) was measured proximally and distally, and the sole depth (P-S) was measured dorsally and palmarly/plantarly. As expected, these distances showed moderate to strong positive correlations in front (W-Tp/W-Td r = 0.53; P-Sd/P-Sp r = 0.72) and hind feet (W-Tp/W-Td r = 0.61; P-Sd/P-Sp r = 0.71). The palmar/plantar angle of the distal phalanx (PA) and sole depth (P-S) showed that the distal phalanx of the hind feet is flatter compared to the front. The results of this study show differences in the positional parameters of distal phalanx compared to other breeds of horses and provides information for veterinarians and farriers working with Colombian Paso Horses.

Changes in Hoof Shape During a Seven-Week Period When Horses Were Shod Versus Barefoot

This crossover study tested the hypothesis that hoof shape would differ after a seven-week period of horses (n = 11) wearing shoes versus barefoot. An ANOVA appropriate to a crossover design was used to assess the differences in the change in hoof shape over the seven-week period and significance was set at p < 0.05. Results are displayed as the mean difference for horses when shod versus barefoot ± the SEM for the left (L) and right (R) front hooves. Proximal hoof circumference (PHC) decreased when horses were shod and barefoot, but this decrease was greater when horses were shod (L -0.65 ± 0.16 cm; p = 0.0026; R -0.78 ± 0.13 cm; p = 0.0002). Hoof angle increased slightly when horses were barefoot and decreased when they were shod (L -1.70 ± 0.31°; p = 0.0004; R -1.84 ± 0.54°; p = 0.0079). Sole length decreased more when horses were barefoot, but this was only significant for the right fore (R 5.07 ± 1.06 mm; p = 0.0010). Solar circumference increased when horses were barefoot but decreased when shod (L -1.19 ± 0.41 cm; p = 0.0182; R -1.50 ± 0.31 cm; p = 0.0010). This is the first study to show a significantly lower PHC when horses were shod compared to barefoot. The study suggests that shod horses may benefit from a shorter shoeing interval to help mitigate the changes in hoof angle.

Solar angle of the distal phalanx is associated with scintigraphic evidence of subchondral bone injury in the palmar/plantar aspect of the third metacarpal/tarsal condyles in Thoroughbred racehorses

BACKGROUND

Subchondral bone injury at the palmar/plantar aspect of the condyles of the third metacarpal/metatarsal bone (MC/MT3) commonly causes lameness and poor performance in racehorses. Injury occurs due to repetitive loading, the magnitude of which may be influenced by the position of the distal phalanx relative to the ground surface, i.e. the solar angle. The association of solar angle and injury at the palmar/plantar condyles of distal MC/MT3 therefore warrants investigation.

OBJECTIVES

Investigate the relationship between solar angle and radiopharmaceutical uptake at the palmar/plantar aspect of distal MC/MT3 on scintigraphic images of racehorses.

STUDY DESIGN

Retrospective case-controlled study.

METHODS

Scintigraphic images of Thoroughbred racehorses presented for poor performance or lameness were graded for intensity of radiopharmaceutical uptake in the palmar/plantar aspect of distal MC/MT3. Solar angle was graded (positive, neutral or negative), referring to the angle of the solar plane of the distal phalanx relative to the ground surface. Repeatability of solar angle (n = 1226 limbs) and agreement with objective radiographic evaluation (n = 52 limbs) were evaluated. Prescintigraphy performance data were collected from race records. Associations between solar angle, performance and radiopharmaceutical uptake were investigated using multivariable logistic regression.

RESULTS

Repeatability of scintigraphic solar angle grading (κ = 0.89, 95% CI 0.87-0.91) and agreement of scintigraphic and radiographic solar angle (κ = 0.88, 95% CI 0.75-0.97) were excellent. Horses that performed best prior to presentation were more likely to have both greater radiopharmaceutical uptake and a neutral/negative solar angle. When controlling for prior performance, horses with neutral/negative forelimb solar angle were twice as likely to have moderate/marked radiopharmaceutical uptake than horses with positive solar angle (P<0.02). Horses with negative hindlimb solar angle were six times more likely to have moderate/marked radiopharmaceutical uptake than horses with positive/neutral solar angle (P<0.001).

MAIN LIMITATIONS

Population bias due to preselected hospital population.

CONCLUSIONS

Both solar angle and race performance are independently associated with increased bone activity in the palmar/plantar aspect of the third metacarpal/tarsal condyles. The Summary is available in Portuguese - see Supporting Information.

The Influence of Body Mass and Height on Equine Hoof Conformation and Symmetry

Despite the likelihood that a horse's mass influences hoof morphology, empirical evidence is lacking. A clearer understanding of factors influencing hoof shape could enable prevention, or better treatment, of foot-based disorders; common causes of equine lameness. The study's aim was to investigate the relationship between horse body size, in terms of mass and height, and fore hoof dimensions. A further aim was to determine changes in the occurrence of hoof asymmetry as body size increases. Height, mass, and fore hoof dimensions; coronet band width (CBW); hoof base width (HBW); dorsal hoof wall angle (DHWA); and hoof spread (HS) of 63 riding school horses were measured within two weeks of routine shoeing. Regression analysis demonstrated positive relationships between body mass and both CBW and HBW in left and right hooves, indicating basic hoof dimensions increased as body mass increased. No relationship between horse height and hoof variables was found, suggesting mass is more influential on hoof morphology. Left and right DHWL were moderately correlated; however, paired t-test results identified a greater right than left DHWA. As left DHWA increased, left HS decreased, indicating development of a more upright hoof geometry. Both left and right HS increased as corresponding HBW increased. Both hooves tended toward a more upright conformation as horse height and body mass increased. However, asymmetries observed suggest a splayed left hoof compared to a "boxy" right hoof. Such morphological adjustments may indicate variation in horn tubule orientation in response to greater structural loading; an important consideration for hoof practitioners.

Does a 4-6 Week Shoeing Interval Promote Optimal Foot Balance in the Working Equine?

Simple Summary

Hoof shape is linked to an increased risk of lameness in the horse and has been shown to adapt to different loading patterns associated with the workload and shoeing interval length. This study investigated how different measurements of the hoof wall and the hoof pastern axis angle changed with work in riding school horses, across a four to six week shoeing/trimming interval. The dorsal hoof wall, and weight bearing and coronary band lengths reduced in size post-shoeing/trimming. This, combined with the increase to the inner and outside hoof wall heights on the digital images despite trimming, suggests that shoeing/trimming increased the vertical orientation of the hoof during the shoeing interval investigated. At the same time, increases in the dorsal hoof wall angle, heel angle, and heel height occurred, promoting a more correct dorsopalmar balance. The changes observed are consistent with the workload of the horses studied. The results suggest that a regular farriery interval of no more than six weeks could prevent excess loading of the structures within the hoof, reducing long term injury risks through cumulative, excessive loading in riding school horses.

Abstract

Variation in equine hoof conformation between farriery interventions lacks research, despite associations with distal limb injuries. This study aimed to determine linear and angular hoof variations pre- and post-farriery within a four to six week shoeing/trimming interval. Seventeen hoof and distal limb measurements were drawn from lateral and anterior digital photographs from 26 horses pre- and post-farriery. Most lateral view variables changed significantly. Reductions of the dorsal wall, and weight bearing and coronary band lengths resulted in an increased vertical orientation of the hoof. The increased dorsal hoof wall angle, heel angle, and heel height illustrated this further, improving dorsopalmar alignment. Mediolateral measurements of coronary band and weight bearing lengths reduced, whilst medial and lateral wall lengths from the 2D images increased, indicating an increased vertical hoof alignment. Additionally, dorsopalmar balance improved. However, the results demonstrated that a four to six week interval is sufficient for a palmer shift in the centre of pressure, increasing the loading on acutely inclined heels, altering DIP angulation, and increasing the load on susceptible structures (e.g., DDFT). Mediolateral variable asymmetries suit the lateral hoof landing and unrollment pattern of the foot during landing. The results support regular (four to six week) farriery intervals for the optimal prevention of excess loading of palmar limb structures, reducing long-term injury risks through cumulative, excessive loading.

A test of the universal applicability of a commonly used principle of hoof balance

This study used a UK trimming protocol to determine whether hoof balance is achieved (as defined by equivalence of geometric proportions) in cadaver limbs (n = 49) and two cohorts of horses (shod, n = 6, and unshod, n = 20; three trimming cycles). To determine equivalence, dorsal hoof wall length (DHWL), distance from the heel buttress to the centre of pressure (HBUT-COP) and distance from dorsal toe to centre of rotation (DT-COR) were calculated as a proportion of bearing border length (BBL) using digital photography. Geometric proportions were tested using Fieller's test of equivalence with limits of difference of 2.8%. In 22 cadaver limbs the location of external COR and COP was also mapped radiographically to the extensor process of the third phalanx and the centre of rotation of the distal interphalangeal joint. Equivalence of geometric proportions was not present following trimming in cadaver limbs or in the two cohorts. Although the dorsal hoof wall to heel wall ratio improved in cadaver and unshod horses after trimming, dorsal hoof wall and lateral heel parallelism was absent in all groups and COP was not consistently in line with the extensor process. Increased COP-COR distance occurred in shod horses and may relate to solar arch flattening. Palmar heel migration, however, occurred more in unshod horses. The study shows that equivalence of geometric proportions as a measure of static hoof balance was not commonly present and widely published measures and ratios of hoof balance rarely occurred in this sample population of horses.

Estudo da correlação de medidas radiográficas indicadoras de laminite em éguas da raça Mangalarga Marchador com e sem sinais de sobrepeso

A avaliação radiográfica do casco é essencial no diagnóstico e na avaliação da laminite em equinos, contudo poucos estudos têm sido feitos em raças nacionais. O objetivo deste trabalho foi realizar a morfometria de imagens radiográficas obtidas do dígito de éguas Mangalarga Marchador (MM), a fim de obter um perfil de medidas indicadoras de laminite nessa população e comparar grupos sem (escore corporal 5 e 6) e com (escore corporal 7 e 8) sinais de sobrepeso. Não houve diferença significativa entre os valores para as medidas dos dois grupos (P>0,05), mas verificou-se correlação positiva entre a distância entre os planos da linha coronária e do ápice do processo extensor (afundamento da falange distal) e indicadores de deposição de gordura localizada no pescoço e na base da cauda. Os achados demonstram que a morfometria radiográfica do dígito dessa população de equinos Mangalarga Marchador difere da de raças estrangeiras. Além disso, nos animais estudados, éguas com escore corporal 7 e 8 não aparentaram estarem mais sujeitas à laminite, uma vez que não houve diferença entre a morfometria de éguas com escore inferior. Entretanto, as correlações positivas entre índices de obesidade e a distância de afundamento da falange distal indicam que éguas Mangalarga Marchador também estão sujeitas à ocorrência de laminite associada à obesidade.

The effect of routine hoof trimming on locomotion score, ruminating time, activity, and milk yield of dairy cows

The objective of this study was to quantify the effect of hoof trimming on cow behavior (ruminating time, activity, and locomotion score) and performance (milk yield) over time. Data were gathered from a commercial dairy farm in Israel where routine hoof trimming is done by a trained hoof trimmer twice per year on the entire herd. In total, 288 cows spread over 6 groups with varying production levels were used for the analysis. Cow behavior was measured continuously with a commercial neck activity logger and a ruminating time logger (HR-Tag, SCR Engineers Ltd., Netanya, Israel). Milk yield was recorded during each milking session with a commercial milk flow sensor (Free Flow, SCR Engineers Ltd.). A trained observer assigned on the spot 5-point locomotion scores during 19 nighttime milking occasions between 22 October 2012 and 4 February 2013. Behavioral and performance data were gathered from 1wk before hoof trimming until 1wk after hoof trimming. A generalized linear mixed model was used to statistically test all main and interactive effects of hoof trimming, parity, lactation stage, and hoof lesion presence on ruminating time, neck activity, milk yield, and locomotion score. The results on locomotion scores show that the proportional distribution of cows in the different locomotion score classes changes significantly after trimming. The proportion of cows with a locomotion score ≥3 increases from 14% before to 34% directly after the hoof trimming. Two months after the trimming, the number of cows with a locomotion score ≥3 reduced to 20%, which was still higher than the baseline values 2wk before the trimming. The neck activity level was significantly reduced 1d after trimming (380±6 bits/d) compared with before trimming (389±6 bits/d). Each one-unit increase in locomotion score reduced cow activity level by 4.488 bits/d. The effect of hoof trimming on ruminating time was affected by an interaction effect with parity. The effect of hoof trimming on locomotion scores was affected by an interaction effect with lactation stage and tended to be affected by interaction effects with hoof lesion presence, indicating that cows with a lesion reacted different to the trimming than cows without a lesion did. The results show that the routine hoof trimming affected dairy cow behavior and performance in this farm.

Biometric hoof evaluation of athletic horses of show jumping, barrel, long rope and polo modalities

This study aimed to evaluate, through biometry, the forelimb hoof of horses participating in show jumping, barrel, long rope and polo competitions. Thirty subjects were assessed in relation to each competition (total of 120 animals). The linear measurements (cm) included the dorsal length of the toe; medial and lateral lengths of the quarter; medial and lateral heights of the quarter; lateral and medial lengths of the heel; medial and lateral heights of the heel; hoof length; hoof width; frog length; and frog width. The following angles (°) were measured: toe angle, pastern angle, heel angle and shoulder palette. The length of the horseshoe, coronet circumference and body weight were also assessed. With the use of hoof biometric evaluation was possible to identify the imbalances of forelimb in athletic horses and the most common were broken-backward hoof angle, with 96.7% of the animals showing this in the right forelimb (RFL) and 95.8% in the left forelimb (LFL); and contracted heels, with 95.0% in the RFL and 87.6% in the LFL. The competition type in which greatest numbers of hoof balance abnormalities were shown was the long rope, followed by the barrel. There were high frequencies of medial/lateral imbalance in all the sports. We conclude that animals used in functional tests have a high incidence of hoof balance abnormalities in the forelimbs.

Validation of a photogrammetric technique for computing equine hoof volume

Assessment of equine foot conformation is often based on linear and angular measurements performed on lateral digital photographs. However, quantification of external foot conformation requires more comprehensive assessments to capture the shape of the entire foot. Volumetric measurements of the hoof capsule represent a summary measure quantifying foot shape. The aim of this study was to develop a method for computation of virtual foot models from digital foot images allowing precise and accurate volumetric measurements. This photogrammetric technique was then assessed for the characterization of foot volume changes associated with foot trimming. Using the technique, three different photographers imaged feet from 18 cadavers at different time points and one analyst processed their images to generate virtual computer models. Volumetric measurements were obtained from these models to determine their precision in the context of 'Photographer', 'Time' and the effect of 'Trimming'. Computed tomographic (CT) imaging was used to assess the accuracy of the photogrammetric method. Pre-trim photogrammetric measurements showed excellent precision and accuracy and the results did not depend on the person acquiring the images. The accuracy of post-trim photogrammetric measurements deteriorated in comparison with the average differences measured by CT imaging (19 cm(3)). Precise volumetric measurements were obtained using the photogrammetric method, but average differences in foot volume after trimming as measured by CT imaging are likely too small to be detected with confidence.

An investigation of the relationships between angles and shapes of the hoof capsule and the distal phalanx

REASONS FOR PERFORMING STUDY

There is little scientific evidence to support the premise that poor foot conformation predisposes to foot pain and lameness.

OBJECTIVES

To determine relationships between external characteristics of the hoof capsule and angles of the distal phalanx; to determine variability in shape of the distal phalanx; and to investigate association between distal phalanx angles and the injury causing lameness.

MATERIALS AND METHODS

Feet were documented photographically and radiographically. Linear and angle measurements were obtained for the hoof capsule and distal phalanx and compared statistically. Horses were categorised according to injury group, and angles and linear ratios were compared between groups.

RESULTS

There was modest correlation between hoof wall and heel angles and angles of the distal phalanx. There was variation in shape of the distal phalanx. There was no significant association between injury type and angles of the distal phalanx, although there was a trend for the angle of the dorsal aspect of the distal phalanx with the horizontal to be smaller in horses with injuries of the podotrochlear apparatus or deep digital flexor tendon compared with other groups.

CONCLUSIONS

There are variations in shape of the distal phalanx largely due to differences in orientation of the concave solar border and the solar border to the horizontal. Variations in shape of the distal phalanx were not accurately correlated with external characteristics of the hoof capsule. There were weak associations between injury groups and angles of the distal phalanx.

CLINICAL RELEVANCE

Further work is required to elucidate risk factors for foot-related lameness.