Uneven Feet Research Articles

Hoof Unevenness in Juvenile Quarter Horses During First 6 Months of Training

The role of hoof morphology is increasingly recognized as a factor associated with lameness incidence in performance horses. The primary objective was to evaluate effect of training initiation on hoof unevenness in Quarter Horses (n = 42; 29 2-year-olds, 13 3-year-olds) over 6-months (m) in training (m0, m2, m4, and m6). Horses were objectively assessed for lameness (inertial sensor system) and photographs and radiographs of feet were taken. Hoof measurements were taken (palmar/plantar angles, frog base width/length, toe length/angle, heel length/angle, heel/foot width, wall height/angle), and analyzed with regards to laterality. Front and hindfoot pairs were determined even if toe angles were within 1.5°. Statistical analyses were performed (Fisher's exact test, mixed-model linear regression, P < .05). There were no differences in distal phalanx palmar/plantar angle between lame/nonlame forelimbs (P = .54) or hindlimbs (P = .20). Unevenness between front feet was seen in toe angle m6 (P < .001), heel length m6 (P = .01) and heel angle over time (P = .006). Unevenness between hind feet was seen at m6 in toe angle (P < .001), heel length (P = .009) and heel angle (P = .02). Lameness incidence did not differ between even and uneven footed horses in forelimbs (P = .64) or hindlimbs (P = .09). In uneven feet, there was no difference in lameness between high versus low foot in forelimbs (P = .34) or hindlimbs (P = .29). Limitations include lack of control group not entering training, lack of consistency in timing data collection to previous trimming, and small sample size. In summary, differences in foot measurements and laterality were noted over time following training initiation in juvenile Western performance horses.

Sensorium

Sensorium

Uneven flat feet and closed shoes produce toenail clinical changes that mimic all types of onychomycosis

Uneven flat feet and closed shoes produce toenail clinical changes that mimic all types of onychomycosis

Radiographic Differences Between Uneven Feet in Horses With Foot Lameness and Admitted for MRI Examination

Unevenness is an important feature of foot conformation and coincides with both kinetic and kinematic asymmetrical locomotor differences. It reportedly may lead to early retirement of elite horses from a warmblood population. The aim of this study was to evaluate the radiological consequences of an uneven feet conformation and on distal limb tissue development. In a retrospective study, the complete sets of good quality radiographs of both distal forelimbs were compared objectively for 121 “foot lame” horses that had been admitted for magnetic resonance imaging of one or both front feet (2003–2010). A chi-square test was used to test for significant radiometric differences between the upright and the lower angle foot (P < .05); 60% of the horses were unilaterally lame in the upright foot, whereas 40% were lame in the lower angle foot, which appeared to be a nonsignificant difference. In 84% of the horses, the navicular bone (NB) had a substantially more radiolucent, osteoporotic structure (P < .05). In 88% of the horses, the deep digital flexor tendon (DDFT) in the upright foot was significantly more radiodense and pronounced than in the lower angle foot (P < .05). The NB showed a significantly more osteoporotic structure as scored in the upright foot than in the lower angle foot, whereas the DDFT appeared was scored more compact in the upright foot than in the lower angle foot, suggesting less tension on the DDFT. In conclusion, radiological differences between uneven feet in foot lame horses seem to be related to differences in distal limb locomotor tissue development.

Preliminary Examination of Farriery and Hoof Care Practices and Owner-Reported Injuries in Sport Horses in New Zealand

Retrospective management and owner-reported injury data, and measurement of forelimb hoof conformation, were collected via a cross-sectional survey from a convenience sample of 96 registered show jumping (n = 67) and dressage (n = 29) horses. Most of the horses were medium- to upper-level performers, aged 9 (interquartile range [IQR] 7–12) years, and in the current rider's ownership for 28 (IQR 12–60) months. The horses were trained 45 (IQR 35–60) minutes, 6 days per week, on a sand or sand mix arena. Failure to train for ≥7 days was reported in 26 of 96 horses, generally associated with lameness diagnosed by a veterinarian (16/29), with a median time-off of 26 (IQR 14–93) days. During the preceding 12 months, 33% of the riders had been working with the farrier on hoof-related issues, 30% of which had involved ≤2 issues. This remedial work often involved a veterinarian (14/30) or allied health practitioner (6/30). Most horses were hot shod (67/89) with conventional fullered shoes. Uneven feet were identified in 16 of 89 horses but were not positively associated with inability to train, possibly reflecting the minor variation between feet. Uneven feet were associated with variation in heel length and angle measurements and a greater sole length and reduced sole width, rather than smaller and boxy. Multiple correspondence plots identified an association of uneven feet with the dressage horses rather than show jumping horses.

Functional Locomotor Consequences of Uneven Forefeet for Trot Symmetry in Individual Riding Horses

Left-right symmetrical distal limb conformation can be an important prerequisite for a successful performance, and it is often hypothesized that asymmetric or uneven feet are important enhancing factors for the development of lameness. On a population level, it has been demonstrated that uneven footed horses are retiring earlier from elite level competition, but the biomechanical consequences are not yet known. The objectives of this study were to compare the functional locomotor asymmetries of horses with uneven to those with even feet.Hoof kinetics and distal limb kinematics were collected from horses (n = 34) at trot. Dorsal hoof wall angle was used to classify horses as even or uneven (<1.5 and >1.5° difference between forefeet respectively) and individual feet as flat (<50°), medium (between 50° and 55°) or upright (>55°). Functional kinetic parameters were compared between even and uneven forefeet using MANOVA followed by ANOVA. The relative influences of differences in hoof angle between the forefeet and of absolute hoof angle on functional parameters were analysed using multiple regression analysis (P<0.05).In horses with uneven feet, the side with the flatter foot showed a significantly larger maximal horizontal braking and vertical ground reaction force, a larger vertical fetlock displacement and a suppler fetlock spring. The foot with a steeper hoof angle was linearly correlated with an earlier braking-propulsion transition. The conformational differences between both forefeet were more important for loading characteristics than the individual foot conformation of each individual horse. The differences in vertical force and braking force between uneven forefeet could imply either an asymmetrical loading pattern without a pathological component or a subclinical lameness as a result of a pathological development in the steeper foot.

Biomechanical Consequences of Uneven Forefeet and Hoof Conformation in Riding Horses

IntroductionThe aims of this study were to quantify the morphological differences between uneven feet, and to evaluate the biomechanical locomotor consequences compared to horses with even feet, considered as normal.MethodsEight anatomical parameters that quantified conformational differences in the distal forelimbs of horses with a varied range of hoof asymmetries (n = 36, of which 2 were lame) were compared using discriminant analysis. Forefeet were subjectively scored for unevenness by one clinician. Kinetics and distal limb kinematics of clinically sound horses (n = 34; the 2 lame horses were excluded) were collected at trot and compared between even (n = 13) versus uneven (n = 21) forefeet and between all feet when classified as flat, medium and upright using MANOVA/ANOVA. The relative influence of contralateral differences in hoof angle and of absolute hoof angle on functional parameters was analyzed by multiple regression (P&lt;0.05).ResultsUnevenness was best determined by the differences in dorsal hoof angle between the forefeet. In uneven footed horses, the flatter foot showed a significantly larger maximal horizontal braking and vertical ground reaction force, a larger vertical fetlock displacement and a suppler limb spring. A steeper hoof angle was linearly correlated with an earlier braking‐propulsion transition. No significant differences were found between individual flat, medium or upright feet.ConclusionsThe conformational differences between the forefeet were more important for loading characteristics than the individual foot conformation. The contralateral differences in vertical force could in fact imply an early, subclinical sign of lameness developing in the steeper forefoot, as these differences were smaller than those reported for subtle, clinically evident lamenesses.Ethical Animal ResearchHorse owners gave informed consent. Sources of funding: FWO grant to S. Nauwelaerts, Research Grant Qualisys to S.J. Hobbs. Competing interests: none.

Lateralised motor behaviour leads to increased unevenness in front feet and asymmetry in athletic performance in young mature Warmblood horses

Foot stance in grazing significantly influences hoof conformation and development from foal to yearling age. To conduct a longitudinal study to establish if the relationship between motor laterality and uneven front feet persisted in 3-year-old horses at the time of studbook selection and to investigate if such laterality and unevenness might influence the horses' ability to perform symmetrically while trotting, cantering and free jumping. Seventeen clinically sound but untrained (with only minimal experience of handling) and sound Warmblood horses that had participated in a previous study were assessed as per the protocol reported. Laterality was tested in a preference test (PT) and z-values were calculated for analysis purposes. Laterality and hoof unevenness were related to both relative limb length and relative head size, while the ability to perform symmetrically was tested in free trot-canter transitions and free jumping exercises. Differences in performance between horses with and without a limb preference in the PT and those with 'uneven' and 'even' feet were tested for differences in performance metrics using Students' t test, while linearity was tested using a regression analysis (P<0.05). Significant laterality was still present in 24% of the 3-year-old horses and the relationship between laterality and uneven feet pairs was stronger than at foal and yearling stages. Horses with significant motor laterality had almost 4 times more unevenness, a smaller head and longer limbs and the relationship between body conformation and laterality was still present. There was a strong linear relation between unevenness, laterality and a bias or side preference for trot-canter transitions. However, this relationship was not significant during the free jumping exercise. Motor laterality and uneven feet pairs were still present and significantly related in the 3-year-old horses and both variables were also strongly related to sidedness in trot-canter transitions. Warmblood studbooks should include quantitative data on laterality at the time of studbook admission as part of the selection criteria.

Heritability of foot conformation and its relationship to sports performance in a Dutch Warmblood horse population

Warmblood horse studbooks aim to breed horses with a conformation that will enable elite future performance, but reduce the risk of injuries and lameness. Negative conformational traits, such as asymmetrical or 'uneven' forefeet would possibly diminish performance. To assess the prevalence and heritability of uneven feet and its genetic relationship to other conformation traits as well as to sporting performance later in life in Warmblood riding horses. The databases of the Royal Dutch Warmblood Studbook (KWPN, n = 44,840 horses) and Royal Dutch Equestrian Sports Federation (KNHS, n = 33,459 horses in dressage and n = 30,474 horses in showjumping) were linked through the unique number of each registered horse. Therefore, heritabilities and genetic and phenotypic correlations could be estimated from the scores of the jury at studbook admission and the sports performance of that population in dressage and jumping over the period 1990-2002. The prevalence of uneven feet was 53% on average, and increased from under 4.5% during the first 3 years of recording to over 8% in the years from 2000 onwards. Heritability estimates of foot conformation traits were moderate and ranged from 0.16 for heel height to 0.27 for hoof shape. The genetic correlation between the trait of uneven feet and performance in competition was negative but weak: -0.09 with dressage and -0.12 with showjumping. Predisposition to uneven feet can be reduced by selection. Because of weak genetic correlations, the increased prevalence is not directly associated with selection for better sports performance or higher conformation grade. If the trait 'uneven feet' arises from a disproportionate relationship between height at the withers and neck length, then selection on conformation grade might result in development of uneven feet. In general, limb conformation has a moderate genetic relationship to conformation grade and foot conformation traits have a genetic relationship to sporting performance. Reducing occurrence of uneven feet by selection is possible, without limiting progress in sport performance.

Influence of foot conformation on duration of competitive life in a Dutch Warmblood horse population

Warmblood horse studbooks aim to breed horses with a conformation that will enable elite future sports performance, but reduce the risk of early retirement due to lameness. Negative conformational traits, such as asymmetrical or 'uneven' forefeet may possibly shorten the career of sporthorses. To investigate the significance of foot conformation at young age to duration of the career of sporthorses. Databases of the Royal Dutch Warmblood Studbook (KWPN) and of the Royal Dutch Equestrian Sports Federation (KNHS) were matched and resulted in a dataset comprising 23,116 records of horses for which their conformation scores and duration of their sports career were available. Survival analysis was used to determine which of the conformation traits had a significant effect on duration of sports career in dressage and jumping at basic and elite level. Duration of competitive life was shorter for jumping than for dressage. A different set of risk factors was found for each level and discipline. The trait 'uneven feet' tended to shorten the competitive life in dressage, but was a significant risk factor at the elite level of jumping. Limb conformation and, in particular, the conformation of the distal limb, are important for duration of competitive life. From the prevalence of uneven feet in sports disciplines, it may be concluded that this is an undesirable trait, particularly at the elite level of jumping, since uneven feet have a detrimental effect on the duration of competitive life in a sporthorse population. This study provided evidence that the conformation trait uneven feet has a negative effect on Warmblood jumping performance and, therefore, breeders should be encouraged to avoid this phenomenon at foal age.

Uneven feet in a foal may develop as a consequence of lateral grazing behaviour induced by conformational traits

Conformational traits are important in breeding, since they may be indicative for performance ability and susceptibility to injuries. To study whether certain desired conformational traits of foals are related to lateralised behaviour while foraging and to the development of uneven feet. Twenty-four Warmblood foals, born and raised at the same location, were studied for a year. Foraging behaviour was observed by means of weekly 10 min scan-sampling for 8 h. A preference test (PT) was developed to serve as a standardised tool to determine laterality. The foals were evaluated at age 3, 15, 27 and 55 weeks. The PT and distal limb conformation were used to study the relation between overall body conformation, laterality and the development of uneven feet. Pressure measurements were used to determine the loading patterns under the feet. About 50% of the foals developed a significant preference to protract the same limb systematically while grazing, which resulted in uneven feet and subsequently uneven loading patterns. Foals with relatively long limbs and small heads were predisposed to develop laterality and, consequently unevenness. Conformational traits may stimulate the development of laterality and therefore indirectly cause uneven feet.

Developmental aspects of distal limb conformation in the horse: the potential consequences of uneven feet in foals

Distal limb conformation is generally accepted to be an important item with respect to performance and soundness in mature horses, but little is known about the developmental aspects. To gain insight into the development of distal limb conformation and to assess the possible consequences of uneven feet in foals. Conformation of the distal front limbs of 23 Warmblood foals was scored visually and measured using radiographs, at ages 27 and 55 weeks. At the same ages, pressure measurements were made under both front feet. At both ages the hoof-pastern axis was broken-backwards on radiographs, but only occasionally recognised as such, when scored by eye. Over time, the hoof angle decreased, while both the angles of the dorsal and solar surfaces of the distal phalanx (P3) increased and the parallelism between hoof wall and P3 improved. The foals with uneven feet at age 27 weeks showed a significant difference in distal limb loading that persisted until age 55 weeks. The alignment of the distal limb in the sagittal plane increased in a 6 month period. Visual assessment was not sensitive enough to appreciate this. The growth processes in the distal limb could not compensate for existing unevenness and ensuing asymmetrical limb loading. Foals have a different conformation of the distal limb from mature horses, which should be taken into account when interpreting radiographs. Unevenness of the feet resulted in asymmetrical loading of the proximal and distal interphalangeal joint, which might lead to increased susceptibility to overload injuries and decreased performance at mature age.