Topic:Locomotion
Locomotion in horses refers to the movement mechanisms that enable horses to walk, trot, canter, and gallop. It involves a complex interplay of the musculoskeletal and nervous systems, allowing for efficient and coordinated movement. Studies on equine locomotion often focus on gait analysis, biomechanics, and the impact of various factors such as conformation, training, and surface conditions on movement. Research in this area contributes to understanding performance, diagnosing lameness, and improving rehabilitation practices. This page compiles peer-reviewed research studies and scholarly articles that explore the biomechanics, gait patterns, and factors influencing locomotion in horses.
Ground reaction force patterns of Dutch warmblood horses at normal trot. This study was undertaken to establish limb loading patterns of sound horses at the trot, to provide a data base against which results for lame horses could be compared. Ground reaction force (GRF) data were collected from 20 clinically sound Dutch Warmblood horses. The data from at least 5 stance phases of each limb were averaged after standardisation to the animal's body mass and to the stance phase duration and resulted in 'representative' GRF data. The symmetry in the vertical GRF peak amplitudes, impulses and the stance phase duration comparing left and right limbs exceeded 97%. By averag...
Application of TrackEye in equine locomotion research. TrackEye is an analysis system, which is applicable for equine biokinematic studies. It covers the whole process from digitizing of images, automatic target tracking and analysis. Key components in the system are an image work station for processing of video images and a high-resolution film-to-video scanner for 16-mm film. A recording module controls the input device and handles the capture of image sequences into a videodisc system, and a tracking module is able to follow reference markers automatically. The system offers a flexible analysis including calculations of markers displacements, d...
Multi-body modelling and simulation of animal locomotion. Multi-body models of musculoskeletal systems can be used to determine internal forces from measured external forces and movements ('inverse dynamics') and to perform simulations of movements using muscle forces or activations as input ('direct dynamics'). Examples of 'direct' simulations of movements in the horse are presented. With a model of the equine hindlimb, the function of the 'passive stay apparatus' could be explained. A model of the forelimb was used to determine force distributions in the digital flexor tendons, and to experiment with various methods to change the force distribution...
Shortening of the forelimb in the horse during the stance phase. Compressions in the forelimb of a horse trotting at 3.7 m/s were studied using high-speed cinematography. From a diagram of shortenings it has been concluded that successive loadings in the longitudinal direction from below signify longer impact time and smaller impact forces compared to a theoretically stiff limb. It is proposed that the limb takes up the impact force passively until the onset of loading at the elbow joint, i.e. 30 ms following first contact.
Recommended terminology for researchers in locomotion and biomechanics of quadrupedal animals. This paper summarizes recommendations for terminology to be used in the description of quadrupedal locomotion and selected aspects of biomechanics. Directional terms and planes of the body (anatomical position, spatial reference systems), joint angulation, conformation, general locomotion terminology, phases of the stride and limb cycle (e.g. step, cadence) and terminology for the description of jumping are described.
Relationship between locomotor forces, hoof position and joint motion during the support phase of the stride of galloping horses. Three methods were used simultaneously to determine the relationships between the vertical forces exerted on the hooves and the positions of the limbs and hooves at the times of peak vertical forces from 2 horses galloping on a track straightaway. Vertical forces were recorded from an instrumented shoe, fetlock joint motion was measured with an electrogoniometer and the angles of the carpus, fetlock and hoof were determined from slow-motion films. At hoof contact, the mean angles of the carpus and fetlock were 181-182 degrees and 199-206 degrees, respectively. Peak vertical forces on the heel ...
Surface strain on the dorsal metacarpus of thoroughbreds at different speeds and gaits. Stacked rectangular rosette strain gages were used to measure surface bone strain on the dorsomedial cortex of the third metacarpal bones in 6 adult Thoroughbred horses during treadmill exercise. The peak principal compressive and tensile strains, angle of the peak strains and strain rate during loading were calculated and compared with speed and gait. At speeds from 4 to 14 m/s loading on the metacarpus resulted in compression of the dorsomedial cortex. Tension only occurred consistently in 1 forelimb of 1 horse at the walk (2 m/s). The angle of peak compression was within 10 degrees of the l...
In vivo tendon forces in the forelimb of ponies at the walk, validated by ground reaction force measurements. The load distribution over tendinous structures in the equine forelimb was studied by computing forces from in vivo signals of implanted liquid-metal strain gauges in 5 ponies. For validation, these tendon forces were converted to joint moments, which were summed and compared to the calculated joint moments caused by the ground reaction force. Mean peak forces per kilogram body weight (n = 5) amounted to 5.2 N/kg for the superficial digital flexor tendon, 3.8 N/kg for the deep digital flexor tendon, 7.3 N/kg for the distal accessory (check) ligament and 8.4 N/kg for the third interosseous musc...
Kinematic gait analysis in equine carpal lameness. Gait analysis plays a major role in the clinical evaluation of equine lameness. It is generally accepted that the clinician expresses the grade of lameness as a subjective score. In this study lameness was objectively assessed using a standardized transient lameness model, in which lameness was induced by intra-articular injection of bacterial endotoxin into the radiocarpal joint of ponies. Lameness was scored by an experienced clinician, and locomotion was recorded simultaneously using a CODA-3 apparatus. The obtained kinematic gait parameters correlated well with the clinical lameness score ...
A preliminary study of transitions between the walk and trot in dressage horses. The object of this study was to determine the limb support sequence during the transitions from walk to trot and from trot to walk in dressage horses under saddle and to test the null hypothesis that the limb support sequence during the transitions is not related to the level of training. Sixteen dressage horses training at novice to FEI Grand Prix level were videotaped performing an average of 9 transitions each from walk to trot and from trot to walk. The 30-Hz videotapes were viewed in slow motion, and based on the limb support sequence the transitions were categorized into two types. In ty...
Kinematics of the standardbred trotter measured at 6, 7, 8 and 9 m/s on a treadmill, before and after 5 months of prerace training. A kinematic study was performed on a group of 8 Standardbred stallions. Recordings were done using a modified CODA-3 optoelectronic kinematic analysis system with the horses running on a treadmill at speeds of 6, 7, 8, or 9 m/s. Linear and temporal gait characteristics, joint angle diagrams and the trajectories of the hoof in a plane perpendicular to the direction of movement were studied. Two consecutive recording sessions were held at an age of 21-23 months, and a third was held 5 months later after an intensive training period. Joint angle diagrams appeared to show a similar pattern for all...
Limits to maximal performance. Body size fundamentally affects maximal locomotor performance in mammals. Comparisons of performances of different-sized animals yield different results if made using relative, rather than absolute scales. Absolute speed may be a reasonable way to evaluate the locomotor performance of an animal that must escape predators in real time. However, comparisons of metabolic power in animals of different size can only be made meaningfully on a mass-specific basis. Numerous factors associated with the mechanics, energetics, and storage of elastic energy during locomotion change with body size, which r...
Quantification of the locomotion of Dutch Warmblood foals. To get an in-depth insight into the ontogeny of the equine locomotor apparatus, the locomotion of 28 Dutch Warmblood foals was recorded at the walk, trot and canter on a treadmill using a CODA-3 apparatus. A great similarity in joint angle-time diagrams was found, although considerable differences in kinematic gait parameters of individual foals could be detected. These results contribute to an objective comparison of the locomotor performance of foals.
Stride characteristics of overground versus treadmill locomotion in the saddle horse. The purpose of this study was to compare the velocity-dependent changes in stride length and stride frequency of horses performing the same incremental exercise test first on a track with a rider and then on a treadmill with a 0 and 3.5% slope successively. Seven French saddle horses undertook the exercise test which consisted of 5 stages of increasing speed for 3 min each with 1 min rest between each stage (1.6, 4.2, 8.3, 9.2 and 10 m/s). The horses were recorded by use of a video camera, and the tapes were analysed with regard to gait parameters. At 1.6, 8.3, 9.2 and 10 m/s, stride frequenci...
Quantification of hind limb lameness in the horse. The three-dimensional optoelectronic locomotion analysis system SELSPOT II was used for kinematic studies of hind limb locomotion patterns. Two groups, 11 sound horses and 15 horses suffering from hind limb lameness, were examined at the trot. Both graphical and quantitative analyses were compared in sound and lame horses. The parameter hip acceleration quotient (HAQ), using the different peaks of vertical acceleration of one hip during one stride, proved to be a suitable value for quantitative analysis of hind limb lameness. In sound horses the HAQ ranged from 1.03 to 1.54, lame horses showed...
Gallop kinematics of Olympic three-day event horses. Limb contact variables of the gallop of 3-day event horses were determined for competitors in the 1988 Seoul Summer Olympic Games. Horses were filmed during the steeplechase, phase B of the speed and endurance test on day 2 of competition. Two 16-mm high-speed cameras were aimed perpendicularly to the direction of subject motion along a straightaway on the steeplechase track, filmed at 200 frames/s. Thirty-four of 48 competitors were filmed and 108 gallop strides analyzed. Velocity (VEL) averaged 12.09 +/- 0.10 m/s (mean +/- SE), stride length (SL) 6.04 +/- 0.05 m and stride frequency (SF) 2.0...
Strain of the musculus interosseus medius and its rami extensorii in the horse, deduced from in vivo kinematics. The in vivo strains of the musculus interosseus medius (suspensory ligament) and its rami extensorii (extensor branches) in the forelimb of the horse were determined from angular changes of the metacarpophalangeal and the distal interphalangeal joints. For this purpose, regression models were fitted to strains and joint angle combinations measured in in vitro limb loading experiments. The in vivo strains were computed from the kinematics of 8 horses at the walk, the trot and the canter. It was found that the extensor branches were strained about 1.0% at hoof impact, which indicates that they p...
Concept of a force-measuring horseshoe. To further develop objective methods in the field of gait analysis a force-measuring horseshoe (FM shoe) has been developed. The ground reaction forces were determined by measuring the degree of displacement between the two solid parts of the shoe. This was done by three removable measuring units (MUs) that were equipped with strain gauges and placed in the toe and in each of the quarter parts. Before performing force recordings the sensors were calibrated with the actual MUs mounted on the shoe. This can be done in the field with a specially developed equipment. The shape of the signal genera...
Quantitative analysis of computer-averaged electromyographic profiles of intrinsic limb muscles in ponies at the walk. The function of several intrinsic muscles of the fore-and hind limbs of 5 ponies walking normally was evaluated via surface electromyography. Electromyographic signals were band-pass filtered, rectified, linear enveloped, and standardized to the stride duration. Mean data from the muscles of the left and right limbs that were obtained from at least 30 strides in 2 recording sessions were recorded as electromyographic signals-time curves. The timing of muscle activity was determined from these graphs. On the basis of the major peaks in the electromyographic signal, muscle functions were identif...
Characterizing bone strain distributions in vivo using three triple rosette strain gages. Three triple-element rosette strain gages were attached to the equine third metacarpal midshaft to record site-specific strains engendered by locomotion. The distribution of strains acting upon the midshaft cross section were characterized using a combined beam theory and finite element model analysis that did not presume the manner by which the bone was inertially loaded. A medium-speed trot (3.6 ms-1) was chosen as a representative speed and gait, with normal and shear strains, and strain energy density (SED) distributions determined throughout the stance and subsequent swing phase. Importan...
Effects of exercise stress on various immune functions in horses. Chemotactic locomotion and luminol-dependent chemiluminescence of neutrophils, mitogen-induced lymphocyte blastogenesis, serum cortisol concentration, immunoglobulin quantification, and leukocyte counts were determined to evaluate the effect of a single strenuous exercise in horses. Increased serum cortisol concentration (P less than 0.01) and an increased neutrophil-to-lymphocyte ratio (P less than 0.05) indicated that horses had been stressed. The chemotactic index and peak chemiluminescence production decreased significantly (P less than 0.05 and P less than 0.01, respectively) 1 day after ...
Four forearm flexor muscles of the horse, Equus caballus: anatomy and histochemistry. Two of the forearm flexors of the horse, the superficial and deep digital flexor muscles, are critical to support the digital and fetlock joints, exhibit differing insertions, and are passively supported by the proximal and distal check ligaments, respectively. These two muscles differ in histochemical composition and architecture. The differences are correlated with the different stress levels transmitted through their tendons, and the different frequencies of clinical breakdown that have been reported. Both muscles contain type I and type IIa fibers. A few type IIb fibers occurred in the dee...
The synchronization of ventilation and locomotion in horses (Equus caballus). Ciné film and synchronized records of respiratory flow were obtained from Thoroughbred racehorses cantering on a treadmill at speeds of 9 and 11 m s-1. Horses and some other galloping and hopping mammals link their breathing and locomotion, taking exactly one breath per stride. Three theoretical mechanisms by which the movements of locomotion might drive ventilation are considered. (i) Flexion of the lumbosacral joint and the resulting forward sweep of the pelvis pushes the viscera against the diaphragm. However, back flexion lags behind ventilation at 11 m s-1 and could not exclusively drive...
Effects of atipamezole on xylazine sedation in ponies. Atipamezole antagonism of xylazine sedation was evaluated in six ponies. Atipamezole (0.15 mg/kg) or saline was injected intravenously 15 minutes after the ponies had been sedated with xylazine (1.0 mg/kg). Arterial blood pressure and gases, pulse and respiratory rates, the electrocardiogram, nose-to-ground distance and a subjective sedation score were recorded. The pretreatment nose-to-ground distance and PaO2 returned to normal sooner after atipamezole than after saline and the ponies' appetite and normal locomotion also recovered sooner. No significant differences were observed between the ...
Elbow extensor muscles of the horse: postural and dynamic implications. Based on histochemical and immunohistochemical evidence, horse elbow extensor muscles are composed of two morphologically distinct muscle groups. The long and lateral heads of the triceps brachii are large, predominantly type II (presumed fast) muscles. The long and lateral heads of the triceps together account for 96% of the weight of the elbow extensors (long head of triceps is 81%). The long and lateral heads contain three histochemical fiber types: types I, IIa and IIb. Type I muscle fibers account for approximately 18 and 27% of the fibers in the long and lateral heads of the triceps, res...
[Useful life, departure rates and causes in sport horses]. A review of the operational life, attrition and lethality rates, major causes of attrition and death for thoroughbred and standardbred race horses and competition horses is given. Because of the lack of data, it was not possible to supply answers for all the sport disciplines. The operational life in sports for thoroughbred race horses was 3.3 years, for standardbred horses 4.1 and for competition horses 5.5 years. Attrition and lethality rates could be determined only for the thoroughbred race horses. The yearly rates of attrition and lethality were 30% and 2% respectively. The major causes o...
Femoral head ostectomy in horses and cattle. Femoral head ostectomy was performed in six horses, three ponies, and four cattle for treatment of fractures of the femoral capital physis, coxofemoral luxation, fractured acetabulum, or severe degenerative joint disease. The procedures were performed via a cranial approach that did not involve osteotomy of the greater trochanter. A dorsal approach for femoral head ostectomy via osteotomy of the greater trochanter was evaluated in three healthy adult ponies. Three animals (2 ponies, 1 calf) were euthanatized within a month and one horse was euthanatized at year 2 due to postoperative complicat...
The pharmacokinetics and locomotor activity of alfentanil in the horse. The pharmacokinetics of alfentanil were investigated in the horse. Four doses of alfentanil (4, 10, 20 and 40 micrograms/kg) were given to four horses at different times and their locomotor activity monitored. Doses of 20 and 40 micrograms/kg produced a significant increase in locomotor activity. The plasma concentrations of alfentanil were measured in six standing horses and the pharmacokinetics calculated. It was found that the decay curves were best described by a biexponential equation. The elimination half-life (t1/2 beta) was 21.65 +/- 3.99 min and the clearance (Cl) was 14.1 +/- 0.7 ml/...
Advances in motion analysis. Time magnification in motion photography allows the observation of events in the stride cycle that normally are beyond the resolution of the human eye. Quantitative analysis goes a stage further by measuring the stride in terms of timing, distance, and angular variables. Motion analysis is a good technique for detecting left-right asymmetries of gait, and the nature of the asymmetries has some value in locating the site of a lameness. Repeated analyses of the same horse allow an objective assessment of the effects of local anesthesia, surgical treatment, or medication. It is anticipated that t...
A mechanical trigger for the trot-gallop transition in horses. It is widely thought that animals switch gaits at speeds that minimize energetic cost. Horses naturally switched from a trot to a gallop at a speed where galloping required more energy than trotting, and thus, the gait transition actually increased the energetic cost of running. However, by galloping at this speed, the peak forces on the muscles, tendons, and bones, and presumably the chance of injury, are reduced. When the horses carried weights, they switched from a trot to a gallop at a lower speed but at the same critical level of force. These findings suggest that the trot-gallop transiti...