Omneity® Pellets
All-In-One Vitamin & Mineral Pellet
Topic:Biomechanics
Biomechanics in horses refers to the study of the mechanical principles that govern movement and physical function in equine species. This field encompasses the analysis of gait, locomotion, and the forces exerted by and upon the horse's musculoskeletal system. Biomechanical studies often involve the use of motion capture technology, force plates, and computer modeling to assess how horses move and how various factors, such as conformation, training, and health status, influence their performance and soundness. Research in equine biomechanics contributes to understanding injury prevention, rehabilitation, and performance optimization. This page compiles peer-reviewed research studies and scholarly articles that explore the mechanics of movement, the impact of external and internal forces, and the applications of biomechanical analysis in equine care and management.
Biomechanical implications of mineral content and microstructural variations in cortical bone of horse, elk, and sheep calcanei. Artiodactyl and perissodactyl calcanei have been recently introduced as models for examining bone for mechanically mediated adaptation. We have reported substantial regional variations in cortical bone microstructure and mineral content within the same cross-section of mule deer calcanei. In part, these variations may be adaptations accommodating the customary presence of predominantly tension, compression, and shear strain modes in mutually exclusive cortical locations. Calcanei from skeletally mature horses, elk, and sheep were examined in order to corroborate these previous findings. From e...
Biomechanical comparison of the Herbert and AO cortical bone screws for compression of an equine third carpal bone dorsal plane slab osteotomy. To assess feasibility of insertion of 4.5-mm Herbert cannulated bone screws (HS) using fluoroscopic guidance and compare the mechanical shear strength of these HS and 4.5-mm AO cortical bone screws (AO) for fixation of dorsal plane slab osteotomies in equine cadaver third carpal bones (C3). Methods: Eight equine cadavers. Methods: Bone mineral composition and density of contralateral C3 were confirmed to be equivalent using dual-energy x-ray absorptiometry. A standard 10-mm C3 slab osteotomy was reduced using HS or AO instrumentation under fluoroscopic guidance. Specimens were loaded in shear ...
Kinematic symmetry index: a method for quantifying the horse locomotion symmetry using kinematic data. This study was conducted to evaluate a method for quantifying locomotion symmetry at trot in sound and lame horses. Using a 3D kinematic analysis system, the kinematics of the limb joints of sound and lame horses were recorded. The differences in motion between the left and right homologous joints were then quantified using a symmetry index based on an inter-correlation method. This method was used to calculate the symmetry indices of the vertical displacements and angle-time diagrams of the joints of each horse. In order to evaluate the sensitivity of this method of quantifying the locomotion...
Pulmonary-locomotory interactions in exercising dogs and horses. In exercising quadrupeds, limb movement is often coupled with breathing frequency. This finding has lead some investigators to conclude that locomotory forces, associated with foot plant, abdominal visceral displacements or lumbo-sacral flexion, are the primary determinants of airflow generation. Analysis of respiratory muscle electrical activation (EMG) and contraction profiles in chronically instrumented dogs and horses, along with measurements of esophageal pressure (Pes) changes and limb movements, provide evidence that each breath during the exercise hyperpnea is determined by respiratory...
Influence of the force applied and its period of application on the outcome of the flexion test of the distal forelimb of the horse. The influence of the force applied and its period of application on the outcome of the flexion test of the distal forelimb was investigated in a group of eight sound horses. The degree of lameness after the flexion test was scored by a standard clinical classification, and by measuring the angle of maximum fetlock extension by means of the infrared light-based MacReflex gait analysis system. There was a good correlation between the clinical score and this electronically recorded kinematic parameter (r = 0.96). Both the force applied and the period of application affected the outcome of the tes...
Variations in the force applied to flexion tests of the distal limb of horses. A pressure-sensitive device was developed to measure the force applied to flexion tests of the distal limb of horses. The mean force applied by a group of experienced clinicians was 150 N which results in a moment on the flexed fetlock joint of about 28.5 Nm. The coefficient of variation of the force applied by one experienced clinician was only about 12 per cent, but the coefficient of variation between clinicians was considerably higher (20 per cent), irrespective of whether the clinicians were considered to be experienced or not. The mean force applied by a group of women examiners (114 N) ...
Comparative morphometry of coxal joint angles. The angles related to the coxal joints were comparatively studied in four-limbed walking animals and two-limbed ones including man and birds. Between animals with both types of walking, no significant difference was observed in the neck-shaft angles (NSA), which was equivalent to the acetabulum angles (ACA) at the connection of the femoral head with the acetabulum. The anteversion angles (AVA) were equivalent to the horizontal ACA. Canine species showed two different forms of the femoral neck with or without modification by the femoral AVA, probably being breed-specific and nutrition-dependent...
The use of functional indexes to evaluate fitness in Andalusian horses. The fitness of 8 Andalusian horses between 3 and 4 years of age was analysed. The animals were subjected to an exercise test on a sandy track consisting of 2 stages of different intensities. The first stage was of submaximal intensity at 4 speeds which increased progressively (4.17, 5.56, 6.94 and 8.33 m/sec.) covering a distance of 1,000 m in each level. Between each of these speeds, the horses rested for 2 min. The second stage was a maximal speed test over the same distance carried out 2 min after the ending of the maximal phase. Data of heart rate, plasma lactate concentration, velocity, P...
The intercarpal ligaments of the equine midcarpal joint, Part 2: The role of the palmar intercarpal ligaments in the restraint of dorsal displacement of the proximal row of carpal bones. To determine the relative contributions of the palmar intercarpal ligaments in the midcarpal joint to the restraint of dorsal displacement of the proximal row of carpal bones. Methods: A biomechanical study of cadaver equine carpi. Methods: Eight equine forelimbs from six thoroughbred horses. Methods: With joints in full extension, the radius was dorsally displaced while midcarpal joint displacement was measured. The restraining force at a joint displacement of 1.5 mm was determined from the load-displacement curve. A ligament or pair of ligaments was then cut and the testing procedure repeate...
Exercise modifies the age-related change in crimp pattern in the core region of the equine superficial digital flexor tendon. One of the current concepts with regard to equine superficial digital flexor tendonitis is that cumulative subclinical microscopic damage weakens the structure, predisposing the tendon to partial or complete rupture. This microtrauma is likely to affect the waveform or crimp of the collagen fibrils, which are the units of tensile strength. Collagen fibril crimp morphology characteristics were determined in superficial digital flexor tendons of 18 horses presented for necropsy. Horses were separated into exercised (n = 9) and non-exercised groups (n = 9), based on recent function. Five of the e...
Modeling study of compensatory head movements in lame horses. To study the role of head movements in lame horses. Methods: 11 Dutch Warmblood horses. Methods: A 2-segment 2-dimensional inverse dynamic model of trotting horses was developed: trunk and head/neck segment joined in a neck joint. Model input consisted of averaged segmental inertial properties and averaged kinematic data, taken from 11 horses, trotting on a treadmill (3.5 m/s) in 3 conditions of induced lameness: sound, mildly lame, and moderately lame. Dynamic and static effects were analyzed. Results: Dynamic effects were found to be considerably larger than static effects. In the moderately...
Development and validation of a series of three-dimensional finite element models of the equine metacarpus. Three-dimensional finite element (FE) models of the left metacarpi of five adult horses were developed from quantitative computed tomography data, using the algorithms of Keyak et al. (1990, J Biomed. Engng 12, 389-397). The metacarpi were then equipped with 12 rosette strain gauges and loaded non-destructively in a mechanical testing machine. The bones and the models were loaded in axial compression, with the load evenly distributed across the distal row of carpal bones, and with a point load placed mediad to the sagittal midline, to a load equivalent to three times body weight (-15 kN); and ...
Inertial properties of Dutch Warmblood horses. The complete set of three-dimensional inertial properties (mass, density, centre of mass, inertial tensor) was determined in 26 segments of six Dutch Warmblood horses. The measurements were performed with frozen segments similar to the procedure described by Lephart (1984, J. Biomechanics 17, 537-543). Based on these data linear regression models were developed for the estimation of inertial properties in living horses. The reproducibility of the dissection procedure was found to range between 2 and 9%. Both mean values and regression models are presented for all parameters. The mean standard ...
Design complexity and fracture control in the equine hoof wall. Morphological and mechanical studies were conducted on samples of equine hoof wall to help elucidate the relationship between form and function of this complex, hierarchically organized structure. Morphological findings indicated a dependence of tubule size, shape and helical alignment of intermediate filaments (IFs) within the lamellae on the position through the wall thickness. The plane of the intertubular IFs changed from perpendicular to the tubule axis in the inner wall to almost parallel to the tubule axis in the outer wall. Morphological data predicted the existence of three crack dive...
Comparison of standardbred trotters exercising on a treadmill and a race track with identical draught resistances. The responses in heart rate, plasma lactate and rectal temperature of standardbred trotters to draught loaded interval exercise on a treadmill and a race track were studied. The horses were exercised with incrementally increasing trotting speeds for two-minute intervals with draught loads of 10, 20 and 30 kilopond (kp) in three different tests. Each trotting interval was followed by two-minute periods at a walk without a draught load. Measurements of heart rate and plasma lactate were made at the end of each interval and the rectal temperature was taken at the end of the exercise. The heart ra...
Model for injury to the foreleg of the Thoroughbred racehorse. A discussion is presented of contributing factors to the injury to the foreleg of the Thoroughbred racehorse. The critical part of the step is taken to be the first 10-20 ms after ground contact as the hoof slides forward and stops. Large nonaxial loads associated with the deceleration of the hoof are shown to arise. Results of accelerometer measurements on the hoof of a horse running at racing speed are presented as well as mechanical properties of the racing surface. The mechanical properties of the track surface, the type of shoe, and the degree of fatigue of the horse all work together to ...
Components of the total kinetic moment in jumping horses. Thirty horses were filmed with a panning camera operating at 50 frames/s as they jumped over a 1.20 x 1.20 m fence. The markers of 9 joints on the horse and 7 joints on the rider were tracked in 2D with the TrackEye system. The centre of gravity and moment of inertia of each segment were calculated using a geometric algorithm and a cylindric model, respectively. The kinetic moment of each part of the horse was calculated after filtering, and resampling of data. This method showed the relative contribution of each body segment to the body overall rotation during the take-off, jump and landing p...
Radiological assessment of the effects of a full rolling motion shoe during asymmetrical bearing. The authors used a new radiological method to assess asymmetrical articular compression of the interphalangeal joints. This method was based on the measurements of 3 angles obtained on dorsopalmar radiographs. Variations of these angles were studied during experimental asymmetrical bearing on unshod feet. It was concluded that 2 angles were interesting parameters to assess asymmetrical articular compression and to define the position of the phalanx in the horny box. Furthermore, variations of these angles induced by experimental asymmetrical bearing were compared without shoe, with a standard ...
Kinematics and kinetics of the carpus. This study investigated the kinematics and kinetics of the carpus during the stance phase. Five Standardbred horses trotted on a treadmill at 8.9 m/s. The kinematics of the horses were filmed and hoof reaction forces (HRF) were recorded. The carpus was overextended throughout most of the stance. There were 2 periods of overextension, a more rapid period in the beginning of the stance and second directly following the first period. Maximal overextension occurred slightly before the second minimum of the braking horizontal HRF. The metacarpal and antebrachial segments rotated counter-clockwise f...
Kinematics in horses at the trot before and after an induced forelimb supporting lameness. The aim of this study was to analyse the biokinematic alterations caused by an induced lameness in the right forelimb of Dutch Warmblood (DWB) horses using a system of computer-aided normal videography. Five mature DWB were recorded with a videocamera (frame rate 1/25) from a lateral view before and after an induced lameness. Before videotaping, passive markers were placed on the skin, over easily identifiable anatomical references to determine the joint angles in the forelimb (always on the flexor side). Lameness was induced using special horseshoes. The lameness was evident at the trot and m...
Comparison of three methods of ulnar fixation in horses. This study compares the mechanical properties of three methods of equine ulnar fixation: dynamic compression plating, pins and wires tension band, and a prototype grip system. Methods: The mechanical properties of dynamic compression plating, pins and wires tension band, and a prototype grip system repair of equine ulnar fractures were evaluated in a cadaveric osteotomy model. Methods: Fifteen pairs of the radius and ulna from equine cadavers. Methods: The three repair techniques were evaluated to mimic the pull of the triceps brachii muscle in single cycle to failure and in cyclic fatigue loa...
Noninvasive photoelastic method to show distribution of strain in the hoof wall of a living horse. A photoelastic method used for materials testing in industry was adapted to show the distribution of strain through the hoof wall in the living horse. Strain was a change in length per unit length in the material of the loaded hoof wall compared with the unloaded condition. Coloured fringes appeared in the photoelastic plastic where there were differences in strain between adjacent sites (strain gradients) in the hoof. Strain distribution was observed in the shod and unshod hoof wall of the front hooves of 6 sound horses with hooves that appeared 'good' to visual inspection, and one unsound ho...
Variability of the limb joint patterns of sound horses at trot. The reproducibility of gait variables for sound horses is essential for the interpretation of their modifications by locomotor disorders. Therefore, the purpose of this study was to evaluate the variability of the limb joint angle patterns in a population of sound horses while they trotted in the conditions of the routine lameness examination (slow trot, just held by hand, on a track, outdoors). The kinematics of 14 French Saddle horses was recorded using a 3-dimensional (3D) kinematic analysis system. Angle-time diagrams were established in the sagittal plane and their intra- and inter-indivi...
Impact during equine locomotion: techniques for measurement and analysis. Impact is implicated in the development of several types of musculoskeletal injury in the horse. Characterisation of impact experienced during strenuous exercise is an important first step towards understanding the mechanism for injury. Measurement and analysis of large, short duration impacts is difficult. The measurement system must be able to record transient peaks and high frequencies accurately. The analysis technique must be able to characterise the impact signal in time and frequency. This paper presents a measurement system and analysis technique for the characterisation of large impac...
Effects of trot quality and collection on the angular velocity in the hindlimbs of riding horses. The angular velocities of the hindlimb angles of 14 horses, including 6 Grand Prix dressage horses, 4 horses judged as good at the trot and 4 horses judged as poor, were analysed. The horse material was the same as previously used by Holmström (1994) in studies on conformation and trotting gaits in the Swedish Warmblood riding horse. Four consecutive strides of each horse and the corresponding pace were analysed and mean velocity curves (Xh) for each angle were calculated. Before calculation the data were filtered forwards and backwards with a Butterworth third order filter with a cut off fre...
Recovery of equine forelimb function after desmotomy of the accessory ligament of the deep digital flexor tendon. The recovery process of the equine locomotor system after desmotomy of the accessory ligament of the deep digital flexor tendon (AL-DDFT) was investigated by studying the movement patterns and joint moments in 6 horses before and 10 days and 6 months following surgery. Using a modified CODA-3 system the joint angles and angular velocities of the lower limb were assessed in the operated forelimb as before the operation. Simultaneously ground reaction forces were measured and joint moments calculated. At 10 days and 6 months after the operation the carpal joint started to bend earlier in the sta...
