bluuebunny/crossref_metadata_2025 huggingface dataset:
Variations in Muscle Activity of Vastus Lateralis and Gastrocnemius Lateralis with Increasing Draft Load
Authors: Crook T , Hodson‐Tole E , Wilson A
Published: June 2014

Introduction

Minimal research has examined the effect of draft loading on equine muscle activity. It is hypothesised that increases in draft load of 10 and 20% body mass (BM) will increase EMG intensity and duration of vastus lateralis (VL) and gastrocnemius lateralis (GL) during walk.

Methods

Data were collected from six Irish Cob geldings (11 ± 4 years; height: 1.47 ± 0.05 m; BM: 490 ± 65 kg) all trained to draft‐load. A modified lorry tyre was used as a loading platform. Surface EMG electrodes were positioned over VL and GL. An accelerometer placed on the left hind hoof collected kinematic data. EMG and accelerometer data at a draft load equivalent to 0 (zero load), 10 and 20% BM were recorded as the horses were led at walk in a 20 m straight line. A stopwatch determined mean speed over 20 m. Mean kinematic and EMG values were determined for 10 consecutive strides. EMG intensities were normalised to each horse. Kolmogorov‐Smirnov test explored data normality. Friedman test (P<0.05) compared between conditions. A pair‐wise Wilcoxon signed ranks test identified where the differences lay.

Results

Data for one horse was excluded because of poor accelerometer data. The remaining horses (n = 5) maintained a constant velocity (1.10 ± 0.02 m/s {SD}) between conditions (P>0.7). VL and GL increased their muscular activity in terms of EMG intensity and duration of contraction with increasing draft load from 0 to 10% and 10 to 20% BM (P = 0.04; n = 5).

Conclusions

Draft loading can be utilised for strength training following injury or to improve athletic performance.

Ethical Animal Research

The study was approved by the Royal Veterinary College Ethics Committee. Sources of funding: Royal Veterinary College. Competing interests: none.
Effect of X‐Ray Beam Angle and Superimposition on Radiographic Evaluation of Kissing Spines Syndrome
Authors: Djernæs J , Vedding Nielsen J , Berg L
Published: June 2014

Introduction

Kissing Spines Syndrome (KSS) represents a major challenge in equine practice. Radiographic examination of dorsal spinous processes (DSP) is therefore often included in sale and insurance cases and in diagnosis of back problems. Measurement of interspinous spaces (ISS) on radiographs is often used when evaluating DSPs. Radiographic examination of the equine back usually consists of two to four images causing beam angle differences between the image center and image borders. In addition, radiographs are 2D representations of 3D structures causing superimposition of anatomical structures. The aim of this study was to investigate if x‐ray beam angle and superimposition affect radiographic evaluation of ISSs.

Methods

Beam angle effect was investigated using latero‐lateral radiographs of the thoracic DSPs. Importance of superimposition of anatomical structures was investigated by comparing radiographic measurements with measurements in comparable CT and MR images. Cadaver backs from six horses were included. Four had a diagnosis of KSS, while two were considered normal. Backs were placed in an upright position on a flat surface for all images. Data were analysed using a linear mixed model with a single random factor, ISS. Significance was set at P<0.05.

Results

X‐ray beam angle significantly influenced measurement of ISS (P<0.02) with differences of up to 2 mm, when measured three positions apart. ISS widths measured in radiographs were significantly lower than in comparable CT (P<0.0001) and MR (P<0.0001) images with differences of up to 3 mm.

Conclusions

These findings suggest that radiographic assessment may result in incorrect evaluation of ISSs.

Ethical Animal Research

Cadaver material was included in the study with signed consent from the horse owners. Sources of funding: Access to imaging facilities was kindly donated by the participating equine clinics and Gentofte Hospital (CT). There was no additional funding. Competing interests: none.
Track Surface Identification Using an Instrumented Horseshoes
Authors: Martin C , Merritt J , Davies H
Published: June 2014

Introduction

Track conditions in Thoroughbred racing significantly impact performance and injury. However, surface effects on limb biomechanics at racing speeds are poorly understood.

Methods

A racing shoe was modified to contain inertial transducers and a strain gauge to provide motion kinematics and a measure of hoof/surface interaction load. A two‐phase non‐linear surface reaction model was defined to represent the hoof deceleration phase, and the hoof penetration phase where the surface reaction force was represented by a quartic stiffness profile and a fixed damping term. Model parameters were determined using an “output error” iteration method for 25 strides at medium gallop. Parameters were compared using a standard t‐test.

Results

The sand track had a significantly greater (P<0.0001) maximum penetration of 61 ± 10 mm (mean ± SD), than the grass track (41 ± 0.5 mm). Both stiffness parameters were significantly different between the two tracks (P<0.0001), but damping parameters did not differ significantly. Hoof impact at high speed involved decelerations of over 100 ‘g’ occurring within milliseconds.

Conclusions

This study demonstrated that a surface reaction model using data acquired from an instrumented horseshoe, distinguished between surface reaction profiles of a sand track and a grass track, as a step towards improving track rating methods. A further challenge will be to develop independent checks on instrument calibrations.

Ethical Animal Research

The study was approved by the University of Melbourne Animal Ethics Committee. Sources of funding: This study was funded by the Rural Industries Research and Development Corporation under project PRJ‐006479, and by a University of Melbourne Research Collaboration Grant. Competing interests: Colin Martin is the Director of SPERERO Pty. Ltd. a consulting and innovations company.
Comparison Between Inertial Sensors and Motion Capture System to Quantify Flexion‐Extension Motion in the Back of a Horse
Authors: Martin P , Chateau H , Pourcelot P , Duray L , Cheze L
Published: June 2014

Introduction

The development of miniaturized inertial sensor technology (IMU) opens new possibilities to assess equine back motion in real‐life situations. The consistency of IMU for measuring dorsoventral displacement of the back has been assessed but orientation has not. The aim of this study was to assess accuracy and consistency of miniaturized inertial sensors for quantification of flexion‐extension of the equine back, compared to motion capture (mocap) as a gold standard.

Methods

One sound horse was trotted (3.5 m/s) and cantered (9 m/s) on a treadmill with synchronized mocap and IMU data collection. The amplitudes of two flexion‐extension angles were calculated between 3 IMUs (T12‐T16‐L2) and with a triad of markers linked to each IMU during 15 consecutive strides for two recordings at each gait. Consistency of sensor measurements was assessed using Lin correlation coefficient.

Results

Thoracic and thoracolumbar angles showed respectively a Lin correlation coefficient of 0.96 (excellent) and 0.87 (good). The difference (mean ± SD) between IMU and mocap were, respectively for the thoracic and thoracolumbar angles, 0.57 ± 0.44 and 0.65 ± 0.47 degrees during trotting, and 0.83 ± 0.67 and 0.63 ± 0.44 degrees during canter.

Conclusions

Angle values calculated with IMU data showed acceptable accuracy consistency for quantification of flexion‐extension movement in a horse's back. These results are encouraging for future development of the method in real‐life situations where mocap systems are unsuited for the quantification of back movements.

Ethical Animal Research

None declared. Sources of funding: The authors thank the Institut Français du Cheval et de l′Equitation, the Association Nationale de la Recherche et de la Technologie and the Conseil Régional d′Aquitaine for financial support, the Pôle Hippolia for logistical support, and CIRALE for loaning the treadmill and the horse. Competing interests: none.
Effects of Thoracic Posture on the Nuchal Ligament in Foetal Foals
Authors: Nestadt C , Davies H
Published: June 2014

Introduction

Controversy surrounds certain head and neck postures in sport horses and their potential impact on the nuchal ligament.

Methods

Three dead near‐term equine foetuses in lateral recumbency with upper‐side neck musculature removed to expose the nuchal ligament were placed in 6 head and neck positions (HNP's) between extreme hyperflexion and hyperextension, along with 3 thoracic positions: Low, Medium and High. In each of these 18 positions, the funicular length, lamella dorsoventral width at the level of C4, and craniocaudal length of the 5 major lamella bands of the nuchal ligament were measured manually.

Results

In intermediate HNP's (HNP1, HNP2), thoracic postures significantly impacted nuchal ligament measurements. Compared to the Medium thorax position, depression and elevation of the thorax decreased lamella sheet widths by 24% (P = 0.014) and 11% (P = 0.267) respectively for HNP1, and by 8% (P = 0.01 for both depression and elevation) for HNP2. More extreme head and neck positions were not associated with any change in measurements of the nuchal ligament with changes in thoracic position.

Conclusions

A decreased width suggests increased tension in an elastic structure. Hence, if the anatomical connections are similar in adults, extreme head and neck postures may reduce the effect that thoracic posture might have on the nuchal ligament in certain unnatural positions required in sport horses and may interfere with normal elastic energy storage in the nuchal ligament during movement.

Ethical Animal Research

The study was performed on material collected during post‐mortem examination. Explicit owner informed consent for participation in this study is not stated. Sources of funding: none. Competing interests: none.
Stride Rates of Quarter Horses and Thoroughbreds During Races of Short and Classic Race Distances
Authors: Nielsen B , Robison C , Fabus T , Kenny J , LeCompte R
Published: June 2014

Introduction

Racing Quarter Horses (QH) typically compete at shorter distances and faster speeds than Thoroughbreds (Tbred). The two components of speed are stride rate and stride length. The hypothesis of this study is that racing QH have greater stride rates than Tbreds, and that stride rate decreases as distance increases, even within breed.

Methods

Five runnings of sprint and classic distance stakes races for both QH (Texas Twister Stakes, 100.6 m; Champion of Champions, 402.3 m) and Tbred (Breeders′ Cup Sprint, 1,207.0 m; Breeders′ Cup Classic, 2,011.7 m) contested from 2008 to 2012 were obtained and viewed by five individuals. Individuals watched each race three times (in slow motion when needed) and the average number of strides per second taken by the winning horse was calculated. Using the PROC Mixed Procedure of SAS, the averages from the five individuals were used to compare differences between breeds, and between distances within a breed. The stride rates were also used to determine average stride length by factoring in length of each race.

Results

The average stride rate was greater for QH than for Tbred (2.88 vs 2.34 strides/sec; P<0.0001). Additionally, stride rate decreased (P<0.0001) as distance increased (2.96, 2.81, 2.45, 2.23 strides/sec, respectively). Stride length was longest in the Tbred races and shortest in the 100.6 m QH race (P<0.0001).

Conclusions

The Tbred stride rates reported here, and associated respiratory rates, have been previously reported and are remarkable. However, QH rates are nearly 25% greater. The associated rapid acceleration and deacceleration of the lower limb and quick breathing rate may have implications for skeletal and respiratory soundness.

Ethical Animal Research

No animals were used in this study and all information was obtained from previously conducted races for which video was publicly available. Sources of funding: Michigan State University and MSU AgBioResearch provided funding for support of investigators conducting this study. Competing interests: none.
Development of the Equestrian Arena Surfaces for the 2012 Olympic Games
Authors: Northrop A , Martin J , Blundell E , Owen A , Hobbs S
Published: June 2014

Introduction

The equestrian arenas at the 2012 Olympic Games were constructed on a unique raised platform. Arena surfaces can be implicated in risk of injury and affect performance, therefore functional properties were examined to ensure preparation was appropriate for this unusual construction. The objective of this work was to assess surface hardness, load carrying capacity and uniformity during the development of a suitable surface for the 2012 Olympic Games. Data were compared from the Olympic site at a test event in 2011, pre‐London 2012 and from developmental test arenas on and off a raised platform.

Methods

In‐situ systematic sampling was used across arenas. A biomechanical surface tester quantified load carrying capacity (peak load), a Clegg impact hammer was used to assess hardness (peak deceleration) and moisture data were analysed in the laboratory. Contour maps and GLMs (applying the arena's structural features as explanatory variables where appropriate) were used to highlight surface heterogeneity.

Results

Significant variation in peak deceleration across the surface was detected at the test event in 2011 (P<0.0001). Peak load (P<0.0001) and peak deceleration (P<0.0001) were higher pre‐London 2012, partly due to enhanced stiffness of the base layer. Higher moisture content found pre‐London 2012 (P<0.001) was considered beneficial for surface consolidation. There was no significant difference between data collected on or off a raised platform following the developmental work. Results highlight the importance of effective water management and sub‐surface construction.

Conclusions

Findings from this work guided decisions made by the surface providers for the 2012 Olympic Games and advanced understanding of methods most appropriate for assessing arenas in‐situ.

Ethical Animal Research

This study was approved by the Faculty of Science and Technology ethics committee at Anglia Ruskin University, Cambridge, UK. Sources of funding: The project was conducted as an independent assessment and consultancy for the surface providers Andrews Bowen Ltd, at Greenwich Park for London 2012. Submission of the work has been approved by Andrews Bowen Ltd. Competing interests: none.
Pressure Plate Evaluation of Forelimb Toe‐Heel and Medio‐Lateral Hoof Balance on a Hard Versus a Soft Surface in Sound Ponies at the Walk and Trot
Authors: Oosterlinck M , Royaux E , Pille F
Published: June 2014

Introduction

Pressure plate analysis has been limited to measurements on a hard surface, whereas horses routinely perform on a soft substrate.

Methods

Five sound unshod ponies were walked and trotted over a pressure plate under 2 different conditions: first, the plate was covered with a 5‐mm rubber mat, and then with an additional 50‐mm layer of sand/synthetic fibres. Peak vertical force (PVF), vertical impulse (VI), peak vertical pressure (PVP), contact area (CA) and stance duration (ST) were obtained. Toe‐heel and medio‐lateral hoof balance curves of the vertical force were calculated (126 Hz). Hard vs. soft surfaces were compared using ANOVA and Kruskall‐Wallis test with pairwise comparisons.

Results

PVF, VI, PVP and ST decreased on the soft substrate, while CA increased (P<0.001). At impact, there was more even load distribution between the toe and heel region on the soft vs. hard surface, both at walk (P<0.001) and trot (P = 0.039), and between the lateral and medial zone at walk (P = 0.006), but not at trot. At mid‐stance, there was more loading of the toe region on the soft vs. hard surface at walk (P = 0.044) and at trot (P = 0.005), while the medial and lateral zone were loaded equally.

Conclusions

The differences observed may be due to dampening effects, measurement errors or gait adaptations. Due to the lack of simultaneous force plate data this cannot be definitively identified, but the first option seems most likely. This study opens perspectives for evaluation of the effects of conformational deficits and therapeutic farriery on hoof loading in relation to arena composition.

Ethical Animal Research

All ponies in the study are part of the faculty teaching herd, institutional guidelines were followed. Sources of funding: Ghent University. Competing interests: none.
Changes in Kinematics During Repeated Jumping
Authors: Rodrigues TN , Godoi FN , Ramos MT , Andrede AM , Almeida FQ
Published: June 2014

Introduction

Kinematic studies allow the assessment of variations in body position during jumping. This study evaluated changes in kinematic variables in horses during a jumping test.

Methods

Eight horses equipped with reflective skin markers were submitted to a jumping test consisting of 70 jumps in 4 series of 10, 15, 20 and 25 times each over a 1.10 m vertical obstacle. Six jumps per series were recorded; a heart rate of ≤ 90 bpm was the criterion to begin the next series. A 25 Hz calibrated camera was placed 10 m from the fence, and 2D images were analyzed. The variables were: overtracking at jumping; take‐off and landing distances; jump length; distance between lowest point of the fore and hind limb and the fence; height of head, withers and croup in relation to the ground when passing the fence; and maximum withers height at jumping. Data were analysed with an ANOVA with a post‐hoc Tukey test (P<0.05).

Results

There was a reduction in take‐off distance (1.65 m to 1.46 m, P = 0.03), landing distance (1.99 m to 1.71 m, P = 0.001), jump length (4.51 m to 4.11 m, P = 0.005), left forelimb distance height above the fence (9.4 cm to 5.1 cm, P = 0.03) and maximum withers height at jumping (2.0 m to 1.95 m, P = 0.001) from the first to the third series. Overtracking before jumping increased from 32 cm to 48 cm (P = 0.003) and there was a reduction of right forelimb height above the fence from 7.3 cm to 2.9 cm (P = 0.04), and of withers and croup height above the fence from 2.0 m to 1.95 m (P = 0.001) and 1.93 m to 1.86 m (P<0.0001) respectively from the first to fourth session.

Conclusions

The increase in the number of jumps resulted in a decrease of take‐off and landing distances, and in the distance between forelimb and fence and the withers and croup height, all indicating decreased jumping efficiency.

Ethical Animal Research

The research was approved by UFRRJ Ethics Committee on Animal Research: UFRRJ/ COMEP‐UFRRJ: 263/2012. Sources of funding: CNPq, CAPES and FAPERJ. Competing interests: none.
The Equine Cervical Spine: Comparing MRI and Contrast‐Enhanced CT Images with Anatomic Slices in the Sagittal, Dorsal and Transverse Plane
Authors: Sleutjens J , Cooley A , Sampson S , Wijnberg I , Back W , van der Kolk J , Swiderski C
Published: June 2014

Introduction

The impact of cervical pathology on performance is of great importance to the equine industry. Accurate diagnosis of cervical disease with imaging modalities, including CT and MRI, requires thorough appreciation of normal cervical anatomy. The objectives of this study were to describe in detail the 3‐dimensional anatomy of the equine cervical spine by comparing anatomical sections with corresponding MR and contrast‐enhanced CT images in the sagittal, dorsal, and transverse plane and to determine the ability of MR and contrast‐enhanced CT imaging to visualize anatomical structures in the cervical spine.

Methods

Three cervical spines of young adults (3–8 years), were collected immediately after humane euthanasia. The spine was stabilized on a frame in a natural flexed position with an angle of 20‐degrees. MR and contrast‐enhanced CT imaging was performed within 6 hours after euthanasia. Anatomical sections of 1 cm were made in the sagittal, dorsal, and transverse plane and compared with corresponding CT and MR images. The intervertebral disk thickness, facet joint angle, amount of cerebrospinal fluid and amount of synovial fluid within each facet joint were quantified.

Results

The anatomical locations of clinically important structures including the facet joints, spinal cord, cervical nerve roots and intervertebral disks were reliably identified in the anatomical sections and their corresponding MR images. Contrast‐enhanced CT images depicted all osseous borders; MR images were superior for soft tissue structures.

Conclusions

This study enhances the understanding of normal cervical spine anatomy and the diagnostic usefulness of cervical MRI and contrast‐enhanced CT in the horse.

Ethical animal research

This study was approved by the animal care and use committee of the Mississippi State University, MS, USA. Explicit owner informed consent for participation in this study is not stated. Sources of funding: Office of Graduate Research and the Department of Clinical Sciences of the College of Veterinary Medicine, Mississippi State University. Competing interests: none.
Towards Reliable Objective Lameness Quantification on the Circle
Authors: Starke S , May S , Pfau T
Published: June 2014

Introduction

Lungeing is part of the standard lameness examination, however it systematically affects movement symmetry even in sound horses. We evaluated a method for objective lameness detection on the circle accounting for this asymmetry bias.

Methods

Twenty‐six horses undergoing lameness examination were equipped with inertial sensors (Xsens) on head, sacrum and tubera coxae. Asymmetry in vertical displacement was quantified for trot on straight line and circle using multiple measures. Horses were classified lame when falling outside the directional reference range of sound horses (directional = ‘normal’ margins and lame limb depending on rein and sign of measure). Objective classification on the circle was compared to subjective evaluation, final diagnoses and objective classification on the straight calculating the proportion of matches. Regression analysis evaluated the association of change in asymmetry between straight line and circle and baseline asymmetry on the straight.

Results

The match between objective classification on the circle and the exact fore‐/hindlimb(s) scored lame subjectively was 81% / 79%. The match with the diagnosed limb(s) was 71% / 85%. There was a high frequency of false positives compared to subjective evaluation. Objective evaluation on the circle added new information compared to assessment on the straight line in 70% (forelimb) / 58% (hindlimb) of instances (contralateral limb lame, bilateral lameness, lame on circle but sound on straight). Change in asymmetry was not associated with baseline lameness (P≥0.062).

Conclusions

Objective lameness evaluation on the circle makes a valuable contribution to patient assessment: e.g. subtle lameness falling within the margins of ‘normal’ on the straight or bilateral lameness could be identified. In future, the predictive value of the proposed technique should be determined.

Ethical Animal Research

The study was approved by the local ethics committee. Explicit owner informed consent for participation in this study is not stated. Sources of funding: Sandra Starke's PhD studentship was funded through the Mellon Trust via the Royal Veterinary College. Competing interests: none.
Breezing Thoroughbred Hoof Accelerations on Dirt and Synthetic Surfaces
Authors: Symons J , Garcia T , Soohoo E , Stover S
Published: June 2014

Introduction

Racetrack surface type has been shown to affect horse injury rates, limb kinematics, and ground reaction forces. Understanding hoof‐surface interactions may direct surface design to reduce the incidence of musculoskeletal injury. Hoof accelerations have been recorded at the trot on different surfaces. This study extends these analyses to racing gallop with quantified surface properties.

Methods

Left fore‐hoof accelerations (triaxial, ± 500 g, 1000 Hz) were collected during gallop (10–16 m/s, 5 Thoroughbred racehorses) on dirt and synthetic surfaces of known shear strengths (shear vane). Accelerometric vectors were filtered (5th order Butterworth, stance 85 Hz, swing 30 Hz). Peak accelerations and stance phase durations (limb preparation, hoof landing {heel‐strike and slide}, support, and grab) were compared using a mixed model analysis of covariance with surface, lead, stride frequency, and interaction fixed effects, and horse random effect.

Results

Peak dorsopalmar accelerations were 40% greater during landing on the synthetic surface (P = 0.06). Grab phase was 32% shorter on the synthetic surface (P = 0.02), with 34% less dorsopalmar impulse/mass (P<0.01). Previously reported failure shear stress of the synthetic surface was 20% greater, compared to dirt (normal stress >400 kN/m2, equivalent to trotting racehorse).

Conclusions

Dorsopalmar hoof accelerations were greater on the surface with greater shear strength (synthetic). The finding that accelerations were greater on the synthetic surface compared to dirt is in contrast to that of trotting horses on all‐weather waxed and crushed sand surfaces. This discrepancy may be due to differences in horse gait, but also large variability in surfaces. Consequently, it is important to quantify surface behaviors to understand the effect of surface design and maintenance on limb biomechanics and propensity for injury.

Ethical Animal Research

Study protocols were approved by the University of California, Davis Institutional Animal Care and Use Committee and owner informed consent was obtained for all study horses. Sources of funding: Grayson Jockey Club Research Foundation Inc., Southern California Equine Foundation. Competing interests: none.
Distal Forelimb Kinematics During the Extended Trot of Dressage Horses Ridden on Two Different Arena Surfaces
Authors: Thornton J , Symons J , Garcia T , Stover S
Published: June 2014

Introduction

Suspensory apparatus injuries are common in dressage horses. Studies demonstrate that surface type affects hoof forces and distal limb kinematics of equine athletes. Because synthetic race surfaces have lower stiffness and limb loads than dirt surfaces, it was hypothesized that dressage horses have less fetlock hyperextension on a synthetic surface than a dirt surface.

Methods

Two‐dimensional, high‐speed videos (250 Hz, 2 ppcm) of 6 dressage horses (ages 8–13; 5 males, 1 female) during extended trot on dirt and synthetic surfaces (6 trials (strides) per horse per surface) were digitized (low‐pass Butterworth filter, 15 Hz). Fetlock and solar hoof angles determined from skin and hoof markers were compared between surfaces using a mixed model ANCOVA that accounted for horse velocity (saddle billet marker) and repeated horse measures. Surface mechanical behaviors were characterized using a track testing device. Maximum force, time to maximum force, maximum displacement, resting rebound, maximum vertical rebound, average stiffness, and maximum load rate were compared between surfaces and time of day (morning, afternoon) using a general linear model ANOVA.

Results

Maximum and toe off fetlock angles were greater on the synthetic surface compared to dirt (Δ = 2°, P = 0.070). Mean maximum fetlock angle on the synthetic surface was 260°. The maximum load rate of the synthetic surface was 5 times greater than the dirt surface (P = 0.0086).

Conclusions

Synthetic surfaces were designed to reduce injuries in equine athletes. Because suspensory apparatus elongation is largely dependent on fetlock extension, it is possible that suspensory apparatus strain is greater on synthetic surfaces. Thus, surface design may require more refinement to promote injury prevention based on horse discipline and gait.

Ethical Animal Research

The University of California, Davis Institutional Animal Care and Use Committee reviewed and approved the protocols used in the study. Owner informed consent was obtained for all study horses. Sources of funding: Merial (A Sanofi Company) in association with the Student Training in Advanced Research (STAR) program, School of Veterinary Medicine, University of California, Davis and the Endowed Research Funds of School of Veterinary Medicine, University of California, Davis. Competing interests: none.
Is Subjective Grading of Jumping Technique Related to Measurable Kinematic Parameters During Flight?
Authors: Walker V , Tranquille C , Hoekstra R , Spear J , Bronsvoort M
Published: June 2014

Introduction

There has been limited evaluation of biomechanical parameters during flight and their relationship to subjective assessments of jumping technique in ridden show‐jumping horses.

Methods

Ten mixed breed horses (9.1 ± 1.9 yrs) were assessed at a British Equestrian Federation (BEF) World Class Performance three day training session. Riders received coaching during warm‐up and after jumping a 15‐fence (1.35–1.45 m) course once on day one and twice on day two; the second round on day 3 was an 8‐fence jump‐off. Two‐dimensional high‐speed motion‐capture (250 Hz) was used to determine limb and back angles at 25%, 50% and 75% of the flight phase over four fences using markers placed at pre‐determined locations. Technique grades (1–10) were assigned per fence by an international coach. Technique grades and kinematics were correlated using a Spearman's rank correlation test.

Results

Forelimb and hindlimb take‐off distance and technique grade (4–7/10) were positively correlated (r = 0.29, 0.27, P≤0.01). Thoracolumbar angle (range 178–184°) at 25% and 75% of flight and neck/trunk angle (NT) at 50% and 75% of flight were negatively correlated with technique grade (r = ‐0.20 {P = 0.04}, ‐0.20 {P = 0.03}, ‐0.21 {P = 0.03}, and −0.28 {P<0.01} respectively).

Conclusions

Only weak correlations were evident, however, the findings suggest that increased take‐off distance may be desirable for improvements in subjectively evaluated technique. The relationship between TL extension and improved technique grades may be explained by improved back stabilisation. Decreased NT and TL extension at 75% flight could suggest that back stabilisation and raising the neck in preparation for landing are associated with better jumping technique. Subjective grading of jumping technique appears to be influenced by kinematic features during flight.

Ethical Animal Research

The Royal College of Veterinary Surgeons confirmed that the procedures carried out were not Controlled Procedures under UK animal experimentation legislation. Explicit owner informed consent for participation in this study is not stated. Sources of funding: The World Class Development Programme is funded by the Department for Culture, Media and Sport, through Exchequer and National Lottery funds, via UK Sport. Competing interests: none.
Jumping Technique Alters Limb Kinematics in Showjumping Horses
Authors: Walker V , Tranquille C , McEwen J , Spalding V , Cnockaert R
Published: June 2014

Introduction

Showjumping (SJ) horses are at increased risk of distal forelimb soft tissue injuries; generally attributed to limb loading on landing. This study investigated relationships between the back, trailing limb angles at take‐off, in flight and at landing.

Methods

Eight showjumpers jumped a 140 cm vertical obstacle (part of a 15‐fence course). Two‐dimensional high‐speed motion‐capture (250 Hz) was used to measure limb and regional back kinematics in the dorsoventral plane from markers placed at predetermined locations. Pearson's correlation tests were used to determine associations between limb and back angles at take‐off, in flight and upon landing.

Results

All markers were clearly visible throughout. Greater head‐neck ventroflexion at take‐off was associated with decreased hock flexion (r = ‐0.81, P = 0.0141), and decreased neck‐trunk angle on landing (r = 0.77, P = 0.03). Greater head‐neck ventroflexion at landing, 50% and 75% flight was associated with decreased carpal extension on landing (r = 0.81, 0.84, 0.73; P = 0.02, 0.01, 0.04 respectively). Increased thoracolumbar and lumbosacral flexion at take‐off was associated with decreased metatarsophalangeal joint extension upon landing (r = 0.78, 0.75; P = 0.03). Greater lumbosacral flexion at 50 and 75% flight (r = ‐0.73, −0.77; P = 0.04, 0.03 respectively) and greater thoracolumbar flexion at 25, 50 and 75% flight was associated with decreased elbow flexion on landing (r = ‐0.87, −0.78, −0.76; P = 0.01, 0.02, 0.03 respectively).

Conclusions

Decreasing head‐neck angle and increasing thoracolumbar and lumbosacral flexion at take‐off and in flight appeared to alter peak joint flexion and extension on landing. This suggests that optimising jumping technique in training may be beneficial to reduce the strain placed on the limbs at landing, which could potentially be valuable given the risk of distal limb soft tissue injuries in SJ horses.

Ethical Animal Research

The Royal College of Veterinary Surgeons confirmed that the procedures carried out were not Controlled Procedures under UK animal experimentation legislation. Explicit owner informed consent for participation in this study is not stated. Sources of funding: The World Class Development Programme is funded by the Department for Culture, Media and Sport, through Exchequer and National Lottery funds, via UK Sport. Competing interests: none.
Effects of Shoeing on Breakover Forces in Icelandic Horses at Walk, Tölt and Trot
Authors: Weishaupt M , Waldern N , Kubli V , Wiestner T
Published: June 2014

Introduction

To enhance expressiveness and regularity of the tölt, Icelandic horses are commonly shod with excessively high and long hooves. The aim of this study was to objectively assess the effect of shoeing on distal interphalangeal (DIP) joint moments of the left forelimb during break‐over at walk, tölt and trot.

Methods

Twelve sound Icelandic horses accustomed to exercise with a rider on a treadmill were assessed with hooves trimmed and shod according to the standards of normal shoeing and with long and high front hooves; besides the 20 x 8 mm steel shoes, this condition included pads and packing material used in competition. Vertical ground reaction forces (GRFz) were measured with an instrumented treadmill. Time of break‐over was determined kinematically. Measuring systems were started synchronously; sampling frequency was 480 Hz. Measurements were taken at 1.34 ± 0.04 m/s (walk), 3.89 ± 0.10 m/s (tölt), and 3.90 ± 0.10 m/s (trot). The DIP joint moment arm was determined on size‐calibrated latero‐medial radiographs of the left front hoof. Differences were tested using a t‐test (walk) or repeated measures ANOVA (tölt, trot).

Results

In the condition with the long and high hooves, DIP joint moment was increased by 18.5% at walk (P<0.001), 17.3% at tölt (P<0.001) and 13.4% at trot (P = 0.017) although vertical GRFz at break‐over was not statistically different between the two shoeing conditions. The increase could be attributed to the 22.7% increase of the lever arm.

Conclusions

High hooves with long toes may have negative implications for the health of the palmar structures of the distal foot.

Ethical Animal Research

The experiment was carried out with the approval of the Animal Health and Welfare Commission of the Canton of Zurich (No. 206/2010). Owners gave informed written consent. Sources of funding: Stiftung Forschung für das Pferd, the Haldimann Stiftung, the Swiss Metall Union, the Stiftung Temperatio, the Swiss Veterinary Office (FVO) and the Islandpferde‐Vereinigung Schweiz. Competing interests: none.
Biomechanical Consequences of Uneven Forefeet and Hoof Conformation in Riding Horses
Authors: Wiggers N , Nauwelaerts S , Bool S , Hobbs S , Back W
Published: June 2014

Introduction

The 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.

Methods

Eight 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<0.05).

Results

Unevenness 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.

Conclusions

The 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 Research

Horse owners gave informed consent. Sources of funding: FWO grant to S. Nauwelaerts, Research Grant Qualisys to S.J. Hobbs. Competing interests: none.
Back‐Shape Changes in Sports Horses
Authors: Greve L , Dyson S
Published: June 2014

Introduction

We have observed major back‐shape changes over time in some horses, the speed of which may be influenced by work‐type, skeletal maturity, nutrition and saddle‐fit. Currently, there are no longitudinal data quantifying changes in back‐shape and no objective data assessing the importance of each variable. The objectives were to: quantify back‐shape changes over time; describe the effects of age, breed, weight, work‐discipline, saddle‐management and pain elicited on palpation.

Methods

Preliminary data from 98 sport horses in regular work in an on‐going one‐year longitudinal study. Weight and management changes were recorded. The thoracolumbar shape was measured at T18, T13 and T8 using a Flexible Curve Ruler [1] every two months. Ratios were calculated for each site for the widths 3 cm and 15 cm ventral to the dorsal midline. Differences in back‐shape were determined using Wilcoxon signed‐rank test. Chi‐square test was used to assess associations between categorical variables, Spearman rank correlation for continuous variables, Mann‐Whitney‐U for continuous variables with binary outcomes and Kruskal‐Wallis to assess ≥3 groups.

Results

T8 and T18‐ratios were significantly different after two months (P<0.001) and T13 after four months (P = 0.004). Decreased ratio at T8 was related to ill‐fitting saddles (P = 0.005), saddles tipping back (P = 0.020), pain on palpation (P = 0.032) and greater age (P = 0.004). Increased T18‐ratio was associated with weight gain (P<0.001), more prevalent in stallions and geldings than mares (P = 0.035) and in dressage horses than other disciplines (P = 0.043).

Conclusions

Back‐shape can change within two months, the speed and direction of which are influenced by saddle‐fit, age and bodyweight. Pain elicited on palpation of the back may indicate that changes have occurred. Thus saddle‐fit should be reassessed.

Ethical Animal Research

The study was approved by the Ethical Review Committee of the Animal Health Trust; there was informed owner consent. Sources of funding: Line Greve is the recipient of a Royal Veterinary College PhD stipend; we acknowledge financial support from World Horse Welfare. Competing interests: none.
Changes in Movement Symmetry During Long‐Term Exercise in Horses
Authors: Nissen AL , Andersen PH , Buhl R , Thomsen MH
Published: June 2014

Introduction

Asymmetry of the trot may occur or increase during endurance rides due to lameness, pain or fatigue. By visual inspection of the movement it is difficult for veterinarians, riders and researchers to distinguish between fatigue and low‐grade lameness, which make objective movement analysis relevant for this purpose. The aim of this study was to determine changes in movement symmetry during long‐term exercise.

Methods

Movement symmetry of 45 horses finishing endurance rides of 120–160 kilometres was determined by tri‐axial accelerometry according to an earlier published method. Data was collected in Denmark and Germany from 5 international competitions between 2011 and 2013. Movement was assessed at trot on a straight‐line in‐hand on the day before the race and 30 mins to 3 hrs after passing the final veterinary examination. An overall symmetry index S was calculated on the basis of trunk accelerations measured at 240 Hz during 8 strides. All trotting sequences were recorded on videotape. A paired t‐test was performed comparing symmetry indices before and after racing for each individual horse.

Results

A significant decrease in post‐ride symmetry was detected (P = 0.0042). This is seen as a lower S‐index before racing (‐6.18; SD = 0.86. CI [‐6.427; −5.923]) compared to after racing (‐5.67; SD = 0.79; CI [‐5.908; −5.434]).

Conclusions

This study indicates that the biomechanical method applied allows quantification of the symmetry of movement during field conditions. Most horses had decreased movement symmetry after the race. Accordingly the study provides the basis for further investigation of the causes, including surface, climate and fitness; and the possible health consequences of asymmetric movement developed during long‐term exercise.

Ethical Animal Research

The study was pre‐approved by the FEI, the local organizing committees, ground jury, and Danish riding association (DRF). Participation was voluntary and the owner or rider signed an informed consent. All information regarding the horses is kept confidential and the horses coded for anonymity. Sources of funding: This study is part of a university and government funded PhD project. Private funding from “Hesteafgiftsfonden” and KDH (Royal Danish Horse Insurance). Competing interests: none.
Cross‐Sectional Area Measurement of Cervical Spinal Muscles
Authors: Rombach N , Pease A , Stubbs N
Published: June 2014

Introduction

In people with neck pain, ultrasonography (US) can measure atrophy and response to physiotherapy in peri‐vertebral muscles of the cervical spine, i.e. m. multifidus and m. longus colli. This study compared the reproducibility of muscle cross‐sectional area (CSA) measurements made by US and MRI (the gold standard) at different levels in the equine cervical spine.

Methods

From US and MRI images of three mature pony cadavers, CSA was calculated at vertebral levels C3‐C6 (m. multifidus) and C2‐C5 (m. longus colli). ANOVA analysis compared US and MRI image acquisition reliability (n = 360) and CSA (n = 1080) among subjects and vertebral levels.

Results

For image acquisition of m. multifidus (C3‐C5), the ICC (95% CI) for MRI and US was 99% and 61%, respectively. Image acquisition was unreliable at C6. CSA calculation did not differ between MRI and US. For m. longus colli (C3‐C5), the ICC for image acquisition was 100% and 88% for MRI and US, respectively. Image acquisition was unreliable at C2. The ICC for CSA calculation was 98% for MRI and 100% for US. For both muscles, the mean CSA was largest at C4 and C5.

Conclusions

Based on these results, ultrasonography could be used in the live horse for reliable CSA measurement of m. multifidus and m. longus colli in the mid‐cervical spine. This technique may advance knowledge of causes and effects of neck pain in horses.

Ethical Animal Research

Approval for this study was obtained under Institutional Animal Care and Use Committee number 02‐11/020‐00. The study was performed on material collected during post‐mortem examination. Explicit owner informed consent for participation in this study is not stated. Sources of funding: Michigan State University CVM Endowed Research Funds. Competing interests: none.
Is There a Relationship between Tail Carriage and Lameness in Horses?
Authors: Weller R , Love A , Clark B , Smith R , Pfau T
Published: June 2014

Introduction

Tail deviation in horses is anecdotally viewed as an indicator of lameness. Compensatory mechanisms in lame horses are well documented, however there is no information published on the relationship between lameness and tail carriage in horses. The objectives of this study were to quantify differences in tail carriage in relation to the type of lameness (front/hind, left/right) and to establish a relationship with confounding variables.

Methods

Videos of 150 horses presented for lameness examination were evaluated. Tail carriage angles were measured in 50 horses and subjectively assessed using a categorical 4‐point scale in 100 horses. Lame leg(s), lameness score(s), age, sex, breed, duration and cause of lameness were recorded. Differences in tail carriage between lameness types were assessed using paired T‐tests (continuous data) or chi‐square tests (categorical data). Logistic regression evaluated the effect of degree and duration of lameness, and age on degree of tail deviation.

Results

87.2% of the horses showed some degree of tail deviation. The mean ± SD tail angle was 92 ± 14.5° (90° = midsagittal) for forelimb and 87 ± 11.2° for hindlimb lameness. The mean ± SD tail angle was 91.1 ± 17.3° for right‐sided and 89.5 ± 16.9° for left forelimb lameness; 89.8° ± 8.8 for right and 86.5°± 9.8 for left hindlimb lameness with no statistically significant difference between front/hind (P = 0.52) or left/right lameness (P = 0.237). No statistically significant correlation was found between degree and duration of lameness, age of horse and presence or degree of tail deviation.

Conclusions

No significant relationship between tail carriage and lameness was identified in this study and tail carriage should therefore not be considered an indicator for lameness.

Ethical Animal Research

This study was approved by the authors′ institution's ethics and welfare committee. Explicit owner informed consent for participation in this study is not stated. Sources of funding: Royal Veterinary College. Competing interests: none.