The musculoskeletal system in horses encompasses the bones, muscles, tendons, ligaments, and joints that facilitate movement and provide structural support. This system is essential for locomotion, athletic performance, and overall health in equine species. The equine skeleton consists of approximately 205 bones, which are connected by joints and supported by a network of muscles and connective tissues. Tendons connect muscles to bones, while ligaments link bones to other bones, contributing to joint stability. The musculoskeletal system is subject to various conditions, including injuries, degenerative diseases, and developmental disorders, which can impact a horse's mobility and performance. This page compiles peer-reviewed research studies and scholarly articles that explore the anatomy, physiology, pathology, and treatment of musculoskeletal conditions in horses.
Vertz J, Deblanc D, Rhodin M, Pfau T.In trotting horses, movement asymmetry is associated with ground reaction force asymmetry. In humans, limb length differences influence contralateral force production. Here we investigate whether horses, in immediate reaction to limb length changes, show movement asymmetry adaptations consistent with reported force differences. Aim of this study was to quantify pelvic and compensatory head and withers movement asymmetry as a function of limb length changes after application of orthotic lifts. In this experimental study movement asymmetry of eleven trotting horses was calculated from vertical d...
Stutz JC, Vidondo B, Ramseyer A, Maninchedda UE, Cruz AM.Therapeutic farriery is part of the management of certain orthopaedic conditions. Non-podal parameters are important as most horses shod with therapeutic shoes are expected to perform again and the choice of shoe type may be influenced by the effects they may have on gait. The aim of this prospective study was to evaluate the effects of three different shoe designs and unshod front feet on forelimb non-podal kinematic variables using an extremity mounted inertial measurement unit (IMU) system under conditions of treadmill and overground exercise on a soft geotextile surface at the trot. Ten so...
Shelver WL, Smith DJ.Zilpaterol is a β-adrenergic agonist feed additive approved in the United States to increase weight gain and improve feed efficiency of cattle. A zilpaterol immunochromatographic assay was developed as an economical and user-friendly rapid detection method for zilpaterol and validated using urine and tissue samples derived from animal studies. The assay sensitivity was 1.7-23.2 ng g or mL across a variety of feed and animal matrices and did not cross-react with clenbuterol or ractopamine. No sample pre-treatment of cattle and sheep urine was needed, but horse urine and feed required dilution;...
Liley H, Zhang J, Firth EC, Fernandez JW, Besier TF.The objective of this study was to describe the three-dimensional shape and subchondral bone mineral density (BMD) variation of the equine distal third metacarpal bone (MC3) using a statistical shape model. The association between form and function builds upon previous two-dimensional observations of MC3 epiphyseal structure. It was expected that the main source of variation would be an increase in overall MC3 bone size, correlated to an increase in subchondral BMD. Geometry and bone mineral density was obtained from CT image data of 40 healthy Thoroughbred horses. This was used to create a st...
Cresswell EN, McDonough SP, Palmer SE, Hernandez CJ, Reesink HL.Fracture of the proximal sesamoid bones continues to be the most common fatal musculoskeletal injury in US racehorses. Identifying factors that influence fracture risk could lead to screening techniques to reduce catastrophic injury rates and improve animal welfare. Objective: To identify morphological differences between proximal sesamoid bones of the contralateral limb of fracture and control horses and assess the feasibility of computed tomography (CT) to detect traits associated with proximal sesamoid bone fracture. We hypothesised that horses with proximal sesamoid bone fracture would hav...
Haussler KK.Manual therapies involve the application of the hands to the body, with a diagnostic or therapeutic intent. Touch therapies, massage, joint mobilization, and manipulation are all critical components in the management of muscular, articular, and neurologic components of select injuries in performance horses. Musculoskeletal conditions that are chronic or recurring, not readily diagnosed, or are not responding to conventional veterinary care may be indicators that manual therapy evaluation and treatment is needed.
García-López JM.Pain localized to the neck, back, and or pelvis can result in a profound effect on the horse's performance. These conditions can present with a varied and nonspecific set of clinical signs. A careful and thorough examination of these areas by means of physical examination, lameness evaluation both in hand and under saddle, diagnostic anesthesia, and the use of multiple imaging modalities in combination is often necessary to have an accurate prognosis. Medical and surgical management where appropriate of the conditions highlighted in this article are discussed as well as their individual progno...
Bubeck KA, Aarsvold S.For successful diagnosis of soft tissue injuries in the sport horse, localizing the area of injury during clinical and lameness evaluation will be followed in most cases by an ultrasonographic examination. With MRI more available in equine veterinary clinics, this modality can allow for a complete evaluation of soft tissue and osseous structures and is especially useful for evaluation of structures within the hoof capsule. This article discusses special ultrasonographic techniques, an overview of MRI image generation, and the use of contrast computed tomography for diagnosis of soft tissue inj...
Valberg SJ.Optimal function of skeletal muscle is essential for successful athletic performance. Even minor derangements in locomotor muscle function will impact power output, coordination, stamina, and desire to work during exercise. In this review, the presenting clinical signs, differential diagnoses, approach to diagnostic testing and treatment of muscle atrophy and weakness, focal muscle strain, and exertional myopathies are discussed. Exertional myopathies include polysaccharide storage myopathies, recurrent exertional rhabdomyolysis, malignant hyperthermia, and myofibrillar myopathy.
Jensen AM, Ahmed W, Elbrønd VS, Harrison AP.It has been proposed that manipulating proprioceptive signals of the equine distal limb as part of a rehabilitation process in cases of musculoskeletal pain or neurologic deficits can be used to correct postural control and restore normal motor programs. This trial has examined the effect of treatment with a light-weight and loose-fitting bell boot (82 g) on an imbalance of muscle gluteus superficialis function in horses as measured using acoustic myography (AMG). Eight horses were trained over a 60-minute period every 3 days for 6 weeks, a protocol based on preliminary findings. Acoustic my...
Malekipour F, Whitton CR, Lee PV.Subchondral bone injury due to high magnitude and repetition of compressive loading is common in humans and athletic animals such as Thoroughbred racehorses. Repeated loading of the joint surface may alter the subchondral bone microstructure and initiate microdamage in the bone adjacent to the articular cartilage. Understanding the relationship between microdamage, microstructure and mechanical properties of the subchondral bone adjacent to the articular cartilage is, therefore, essential in understanding the mechanism of subchondral bone injury. In this study, we used high-resolution µCT sca...
Contino EK.Joint disease is one of the most common issues effecting sport horses. Because there is no cure for joint disease, treatment goals surround slowing progression of the disease, minimizing pain, increasing function, and optimizing performance. Accomplishing these goals often requires a multimodal approach that combines systemic medications or supplements; intra-articular therapies, such as corticosteroids or biologics; management considerations; and physical therapy exercises.
O'Leary SA, White JL, Hu JC, Athanasiou KA.The equine cervical facet joint is a site of significant pathology. Located bilaterally on the dorsal spine, these diarthrodial joints work in conjunction with the intervertebral disc to facilitate appropriate spinal motion. Despite the high prevalence of pathology in this joint, the facet joint is understudied and thus lacking in viable treatment options. Objective: The goal of this study was to characterise equine facet joint cartilage and provide a comprehensive database describing the morphological, histological, biochemical and biomechanical properties of this tissue. Methods: Descriptive...
Sun TC, Riggs CM, Cogger N, Wright J, Al-Alawneh JI.Reports of fractures in racehorses have predominantly focused on catastrophic injuries, and there are limited data identifying the location and incidence of fractures that did not result in a fatal outcome. Objective: To describe the nature and the incidence of noncatastrophic and catastrophic fractures in Thoroughbreds racing at the Hong Kong Jockey Club (HKJC) over seven racing seasons. Methods: Retrospective cohort study. Methods: Data of fractures sustained in horses while racing and of race characteristics were extracted from the HKJC Veterinary Management Information System (VMIS) and Ra...
Whitton RC, Ayodele BA, Hitchens PL, Mackie EJ.Microdamage accumulation leads to subchondral bone injury and/or fracture in racehorses. An understanding of this process is essential for developing strategies for injury prevention. Objective: To quantify subchondral bone microdamage in the third metacarpal bone of Thoroughbred racehorses at different stages of the training cycle. Methods: Cross-sectional. Methods: Bone blocks from the palmar aspect of the medial condyles of third metacarpal bones from 46 racing Thoroughbred horses undergoing post-mortem were examined with micro computed tomography (microCT) to detect calcified microcracks, ...
Barstow A, Bailey J, Campbell J, Harris C, Weller R, Pfau T.Both pleasure and competition horses regularly exercise on surfaces such as tarmac, gravel and turf during 'hacking'. Despite this, there is limited evidence relating to the effect of these surfaces upon foot-surface interaction. Objective: To investigate forelimb foot placement, hoof vibration and movement symmetry in pleasure horses on three commonly encountered hacking surfaces. Methods: Quantitative gait study in a convenience sample. Methods: Six horses regularly partaking in hacking exercise were ridden in walk and trot on all surfaces. Horses were equipped with one hoof-mounted, acceler...
Quiney LE, Ireland JL, Dyson SJ.There is good correlation between increased radiopharmaceutical uptake anywhere in the feet of sports or leisure horses and the presence of foot pain. However, low sensitivity of scintigraphy for identifying lesions contributing to foot pain as determined by magnetic resonance imaging (MRI) has been reported. The aim of this retrospective, cross-sectional, analytical study was to assess the accuracy of scintigraphy for identifying the cause(s) of foot pain, using MRI as the reference standard. Sports and leisure horses that underwent both skeletal scintigraphy and MRI of the front feet between...
MacDonald JL, Richter RA, Wimer CL.Ultrasonography is an established diagnostic test for evaluating horses with foot pain due to suspected podotrochlear apparatus pathology. However, variations from the previously reported normal appearance of the distal sesamoidean impar ligament have not always coincided with lameness. The objective of this prospective, cross-sectional, descriptive study was to characterize variations in the ultrasonographic appearance of the distal sesamoidean impar ligament in sound horses using the transcuneal approach. Transcuneal ultrasonography of the distal sesamoidean impar ligament was performed on s...
Quiney LE, Ireland JL, Dyson SJ.Skeletal scintigraphy is an established imaging modality, however, its validity as a diagnostic test in lame or poorly performing sports horses has not been determined. The objective of this retrospective cross-sectional analytical study was to determine the accuracy of skeletal scintigraphy as an indiscriminate screening test in sports horses. All sports horses that underwent scintigraphic examination between March 2008 and December 2014 for which a definitive diagnosis was reached were included. Examinations were evaluated blindly. Characteristics of increased radiopharmaceutical uptake were...
Pitti L, Oosterlinck M, Díaz-Bertrana ML, Carrillo JM, Rubio M, Sopena J, Santana A, Vilar JM.Static posturography and pedobarography are based on the detection of postural imbalance and, consequently, the pressure redistribution between limbs in lame subjects. These techniques have proven to be useful for the detection of lameness in humans and dogs. The main objective of this study was to test the suitability of static posturography and pedobarography in diagnosing lameness in ponies. A pressure platform was used to obtain postural data (statokinesiograms, mean X and Y, length, LFS ratio, and mean velocity) from 10 sound ponies and 7 ponies with unilateral forelimb lameness. Static p...
Nauwelaerts S, Clayton HM.Data describing segmental masses and moments of inertia (MOI) of limb segments are required for inverse dynamic calculations. In horses, these values are usually calculated using regression equations that have been developed from a limited number of horses representing a small number of breeds. The objective of the present study was to evaluate the performance of a scaling method and a pictorial method for estimating of the values of segmental masses, lengths, and MOI in the equine limb segments by comparing their output with the standard technique involving direct measurements. Limbs of 30 ho...
García Liñeiro JA, Graziotti GH, Rodríguez Menéndez JM, Ríos CM, Affricano NO, Victorica CL.The epaxial muscles produce intervertebral rotation in the transverse, vertical and axial axes. These muscles also counteract the movements induced by gravitational and inertial forces and movements produced by antagonistic muscles and the intrinsic muscles of the pelvic limb. Their fascicles are innervated by the dorsal branch of the spinal nerve, which corresponds to the metamere of its cranial insertion in the spinous process. The structure allows the function of the muscles to be predicted: those with long and parallel fibres have a shortening function, whereas the muscles with short and o...
Poon ET, O'Reilly J, Sheridan S, Cai MM, Wong SH.Weight-making practices, regularly engaged in by horse racing jockeys, have been suggested to impair both physiological and mental health. This study aimed to assess bone health markers, nutritional intake, bone-specific physical activity (PA) habits, and quality of life of professional jockeys in Hong Kong (n = 14), with gender-, age-, and body mass index-matched controls (n = 14). Anthropometric measurements, serum hormonal biomarkers, bone mineral density, bone-specific PA habits, nutritional intake, and quality of life were assessed in all participants. The jockey group displayed s...
Dabbene I, Bullone M, Pagliara E, Gasparini M, Riccio B, Bertuglia A.Information on interference injuries in racehorses is lacking. Objective: To describe clinical findings and prognosis of palmar forelimb interference injuries in Standardbreds. Methods: Retrospective cohort study. Methods: Records of 74 racehorses sustaining palmar forelimb interference injuries were studied; 7 occurred during training and 67 during racing. The number of starts before injury, hind shoeing status, gait penalties and racing speeds in cases occurring during racing were compared with negative controls (67 age, sex and speed category matched horses) from the same races. The number ...
Salonius E, Rieppo L, Nissi MJ, Pulkkinen HJ, Brommer H, Brünott A, Silvast TS, Van Weeren PR, Muhonen V, Brama PAJ, Kiviranta I.The horse joint, due to its similarity with the human joint, is the ultimate model for translational articular cartilage repair studies. This study was designed to determine the critical size of cartilage defects in the equine carpus and serve as a benchmark for the evaluation of new cartilage treatment options. Circular full-thickness cartilage defects with a diameter of 2, 4, and 8 mm were created in the left middle carpal joint and similar osteochondral (3.5 mm in depth) defects in the right middle carpal joint of 5 horses. Spontaneously formed repair tissue was examined macroscopically, ...
Adair S, Baus M, Belknap J, Bell R, Boero M, Bussy C, Cardenas F, Casey T, Castro J, Davis W, Erskine M, Farr R, Fischer T, Forbes B, Ford T....No abstract available
Zsoldos RR, Voegele A, Krueger B, Schroeder U, Weber A, Licka TF.The equine m. gluteus medius (GM) is the largest muscle of the horse, its main movement function is the extension of the hip joint. The objective of the present study was to measure equine GM activity in three adjacent locations on GM during walk and trot on a treadmill, in order to document potential differences. Fourteen Haflinger mares were measured using surface electromyography and kinematic markers to identify the motion cycles on three occasions over 16 weeks. The electrodes were placed on left and right gluteus medius muscle over the middle of its widest part and 5 cm lateral and med...
Smith LCR, Wylie CE, Palmer L, Ramzan PHL.There is a need for investigation of associations between intrasynovial medication and fracture risk in racehorses. Objective: To document the proportion and type of fracture occurring following intrasynovial medication. Methods: Retrospective longitudinal study. Methods: Review of clinical records from all Thoroughbred flat racehorses receiving intrasynovial medication under the care of a first-opinion veterinary practice between 2006 and 2011. Fractures pre- and post-medication were categorised by location, type, and severity; analysis of fractures sustained within 56-days of medication was ...
Journée SL, Journée HL, de Bruijn CM, Delesalle CJG.There are indications that transcranial electrical stimulation (TES) assesses the motor function of the spinal cord in horses in a more sensitive and reproducible fashion than transcranial magnetic stimulation (TMS). However, no normative data of TES evoked motor potentials (MEP) is available. Results: In this prospective study normative data of TES induced MEP wave characteristics (motor latency times (MLT); amplitude and waveform) was obtained from the extensor carpi radialis (ECR) and tibial cranialis (TC) muscles in a group of healthy horses to create a reference frame for functional diagn...
Gottlieb M, Essén-Gustavsson B, Lindholm A, Persson SG.Five Standardbred trotters were trained on a treadmill 3 times/wk for 12 wk by intervals of draft-loaded exercise. The draft load was 34 kp and the velocity approximately 7 m/s. Muscle biopsies were taken from the gluteus medius and longissimus muscles before training and after 2, 4, 8, and 12 wk of training and from the brachiocephalicus muscle before and after training. Both the percentage and the area of type IIa fibers increased and the percentage of type IIb fibers decreased in the gluteus medius muscle during the first 2 wk of training, and then no further significant difference was note...
Kienapfel K, Preuschoft H, Wulf A, Wagner H.The activity patterns of trunk muscles are commonly neglected, in spite of their importance for maintaining body shape. Analysis of the biomechanics of the trunk under static conditions has led to predictions of the activity patterns. These hypotheses are tested experimentally by surface electromyography (EMG). Five horses, with and without a rider, were examined in the walk, trot and canter. Footfall was synchronised with EMG by an accelerometer. Averages of ten consecutive cycles were calculated and compared by statistical methods. The start and stop times of the muscle activities of 5-10 un...
Love S, Wyse CA, Stirk AJ, Stear MJ, Calver P, Voute LC, Mellor DJ.The assessment of belief that equine conformation is associated with performance and durability is a fundamental concept of horsemanship. Surprisingly, there is almost no quantitative evidence to support these beliefs. Objective: To assess the prevalence and heritability of conformational traits in Thoroughbred yearlings, and investigate their significance for subsequent turf flat-racing performance and durability. Methods: Nine selected conformational traits were assessed in a consistent, qualitative manner by a single veterinary observer and entered into a database together with details of p...
Steiss JE, Naylor JM.A three year old Quarter Horse stallion was presented with a one year history of episodes of generalized muscle tremors and stiffness, and spasm of the muscles of facial expression, lasting 10-15 minutes. Between attacks, the horse was either normal or had a localized muscle tremor in the flank region. Episodes appeared unrelated to exercise. The major abnormal findings included 1) a rise in plasma potassium from a resting level of 4.4 to 7.9 mmol/L during an attack and 2) electromyographic findings of generalized increased insertion activity and myotonic discharges. The horse was treated with...
Stewart HL, Siewerdsen JH, Nelson BB, Kawcak CE.Access to volumetric imaging modalities, such as magnetic resonance imaging (MRI) and computed tomography (CT), has increased over the past decade and has revolutionised the way clinicians evaluate equine anatomy. More recent advancements have resulted in the development of multiple commercially available cone-beam CT (CBCT) scanners for equine use. CBCT scanners modify the traditional fan-shaped beam of ionising radiation into a three-dimensional pyramidal- or cone-shaped beam of radiation. This modification enables the scanner to acquire sufficient data to create diagnostic images of a regio...
Johnston C, Holmt K, Faber M, Erichsen C, Eksell P, Drevemo S.The relationship between structure and function is important in the judgement of the horse. Twenty sound riding horses walked and trotted on a treadmill. The movement of the backs of each of the horses was measured using a commercially available movement analysis system. Morphometric, spatiotemporal and kinematic information were correlated to investigate the effect of conformation on movement. Taller and heavier horses seem to have longer thoracic and lumbar backs, and are wider at the pelvis. Horses with longer strides extended and flexed their backs in the caudal saddle region to a greater ...
Steel CM, Hopper BJ, Richardson JL, Alexander GR, Robertson ID.Lameness related to the middle carpal joint (MCJ) occurs in up to 30% of young Standardbred horses in race training and the incidence increase with radiographic severity of third carpal bone (C3) sclerosis on DPr-DDIO (skyline) view of the carpus. Factors predisposing horses to carpal injury have not been well investigated. Objective: To determine the importance of MCJ lameness as a cause of wastage in young Standardbred racehorses, stage of training at which it occurs and predisposing factors, and to describe clinical findings and diagnosis. Methods: Standardbred horses (n = 114) entering the...
Ringer SK, Lischer CJ, Ueltschi G.To monitor the effect of focused extra-corporeal shock wave therapy (ESWT) on bone and bone-tendon junction of horses without lameness by use of nuclear scintigraphy and thermography. Methods: 6 warmblood horses without lameness. Methods: The origin of the suspensory ligament at the metacarpus (OSL-MC) and the fourth metatarsal bone were treated at 2 time points (days 0 and 16) with 2,000 shocks applied by a focused ESWT device at an energy flux density of 0.15 mJ/mm2. One forelimb and 1 hind limb were treated, and the contralateral limbs served as controls. To document the effect of focused E...
Gangl M, Serteyn D, Lejeune JP, Schneider N, Grulke S, Peters F, Vila T, Deby-Dupont G, Deberg M, Henrotin Y.Markers of cartilage breakdown enable studying the degradation of cartilage matrix in equine joint pathologies. This study was designed to determine the levels of Coll2-1, a peptide of the triple helix of type II collagen, and Coll2-1NO(2), its nitrated form in the plasma of healthy horses (controls; n=37) and horses suffering from osteochondrosis (n=34). Clinical and arthroscopic scores were attributed reflecting the severity of lesions and were related to the plasma levels of Coll2-1 and Coll2-1NO(2). The median of Coll2-1 was significantly higher in the control group, whereas the mean of Co...
Szcześniak KA, Ciecierska A, Ostaszewski P, Sadkowski T.Adult skeletal muscle myogenesis depends on the activation of satellite cells that have the potential to differentiate into new fibers. Gamma-oryzanol (GO), a commercially available nutriactive phytochemical, has gained global interest on account of its muscle-building and regenerating effects. Here, we investigated GO for its potential influence on myogenesis, using equine satellite cell culture model, since the horse is a unique animal, bred and exercised for competitive sport. To our knowledge, this is the first report where the global gene expression in cultured equine satellite cells has ...
Starke SD, May SA, Pfau T.Hind limb lameness detection in horses relies on the identification of movement asymmetry which can be based on multiple pelvic landmarks. This study explains the poorly understood relationship between hind limb lameness pointers, related to the tubera coxae and sacrum, based on experimental data in context of a simple rigid body model. Vertical displacement of tubera coxae and sacrum was quantified experimentally in 107 horses with varying lameness degrees. A geometrical rigid-body model of pelvis movement during lameness was created in Matlab. Several asymmetry measures were calculated and c...
Rosanowski SM, Chang YM, Stirk AJ, Verheyen KLP.A key focus of the racing industry is to minimise the number of race-day distal limb fractures although no studies have identified risk factors for both fatal and non-fatal distal limb fractures. Objective: To determine risk factors for race-day distal limb fractures experienced by Thoroughbred racehorses participating in flat racing in Great Britain (GB). Methods: Retrospective cohort. Methods: Information was collected from all flat racing starts occurring on GB racecourses between 2000 and 2013, including horse, race, course, trainer and jockey data for each horse start and race-day injury ...
Janis CM, Constable EC, Houpt KA, Streich WJ, Clauss M.It is often assumed that horses chew food more intensively during ingestion than cattle, which - as ruminants - complete part of the mastication during rumination. This has been proposed as a reason for more robust mandibles, larger masseter insertion areas and larger masseter muscles in horses as compared to cattle and other grazing ruminants. In this study, we evaluate results of comparative feeding trials with three horses (338-629 kg) and three cows (404-786 kg), on four different roughages. Ingestion time (s/g dry matter) and chewing intensity (chews/g dry matter) differed among animals w...
Fairburn AJ, Busschers E, Barr ARS.Suspensory ligament branch (SLB) desmopathy is a common cause of lameness and an important cause of lost training in the Thoroughbred racing industry. Studies have assessed the impact of insertional injuries of the SLB on the careers of flat racehorses and established the prevalence of subclinical ultrasonographic SLB abnormalities in this population, but little work has investigated SLB injury in National Hunt (NH) racehorses. Objective: To investigate the prevalence of subclinical ultrasonographic SLB abnormalities in NH racehorses with no clinical signs or history of SLB injury and to estab...
Atalaia T, Prazeres J, Abrantes J, Clayton HM.Injuries to the locomotor system are a common problem in athletic horses. Veterinarians address these injuries using appropriate medical, surgical, and pharmacological treatments. During or after recovery from the initial injury, horses may be treated for functional locomotor deficits using specific rehabilitation techniques aimed at restoring full athletic performance. This study reviews the literature to identify which rehabilitative techniques have been used most frequently in horses over the past 20 years, the protocols that were used, and the outcomes of the treatments in naturally occurr...
Marunova E, Hoenecke K, Fiske-Jackson A, Smith RKW, Bolt DM, Perrier M, Gerdes C, Hernlund E, Rhodin M, Pfau T.Evaluation of diagnostic anesthesia during equine lameness examination requires comparison of complex movement patterns and can be influenced by expectation bias. There is limited research about how changes in movement asymmetries after successful analgesia are affected by different exercise conditions. Movement asymmetry of head, withers and pelvis was quantified in N = 31 horses undergoing forelimb or hindlimb diagnostic anesthesia. Evaluation on a straight line and a circle was performed with subjective diagnostic anesthesia outcome and quantitative changes recorded. Mixed linear mode...
Read EK, Read MR, Townsend HG, Clark CR, Pharr JW, Wilson DG.To evaluate the effect of hemi-circumferential periosteal transection and elevation (HCPTE) in foals with, experimentally induced angular limb deformities. Methods: Prospective study. Methods: 10 healthy foals. Methods: When foals were 30 days old, transphyseal bridge implants were placed on the lateral aspects of both distal radial physes. At 90 days of age (or when 15 degrees of angulation had developed), implants were removed, and HCPTE was performed on 1 limb. Foals were confined in small pens after surgery; the front feet of the foals were rasped weekly to maintain medial-to-lateral hoof ...
Zedda M, Lepore G, Biggio GP, Gadau S, Mura E, Farina V.A high number of differences exist in bone histological features depending on the species, breed, age and bone. Moreover, osteon distribution may vary in the different sides of a bone as a consequence of different biomechanical strains. The aim of this work was to study the distribution and morphology of osteons in different sides of the equine femoral diaphysis with the attempt to correlate them to the main strains operating on them. The following parameters of secondary osteons and Haversian canals were measured in the transverse sections of diaphyses: perimeter, area, minimum and maximum di...
Farber M, Schamhardt H, van Weeren R, Barneveld A.To determine the validity of using skin-fixated markers to assess kinematics of the thoracolumbar vertebral column in horses. Methods: 5 Dutch Warmblood horses without abnormalities of the vertebral column. Methods: Kinematics of T6, T10, T13, T17, L1, L3, L5, S3, and both tuber coxae were determined by use of bone-fixated and skin-fixated markers. Three-dimensional coordinate data were collected while horses were walking and trotting on a treadmill. Angular motion patterns were calculated and compared on the basis of 2-dimensional analysis of data from skin-fixated markers and 3-dimensional a...
Palmer JL, Bertone AL, Malemud CJ, Carter BG, Papay RS, Mansour J.The relevance of site and the influence of exercise on third carpal articular cartilage proteoglycan (PG) were assessed in 16 horses. Six horses were exercised (exercised group) for 30 minutes, 3 times/wk, for 6 weeks. The other 10 horses (nonexercised group) were housed in box stalls for the same 6-week period. At week 6, articular cartilage from the proximal surface of the right third carpal bone was harvested and cultured with radioactive sulfate to label newly synthesized PG. Endogenous PG was measured by use of a uronic acid assay. Newly synthesized and endogenous PG were characterized by...
Petersen GF, Hilbert B, Trope G, Kalle W, Strappe P.Equine adipose-derived mesenchymal stem cells (EADMSC) provide a unique cell-based approach for treatment of a variety of equine musculoskeletal injuries, via regeneration of diseased or damaged tissue, or the secretion of immunomodulatory molecules. These capabilities can be further enhanced by genetic modification using lentiviral vectors, which provide a safe and efficient method of gene delivery. We investigated the suitability of lentiviral vector technology for gene delivery into EADMSC, using GFP expressing lentiviral vectors pseudotyped with the G glycoprotein from the vesicular stomat...
Karlström K, Essén-Gustavsson B, Lindholm A.Samples were taken at slaughter from heart and both locomotor and nonlocomotor muscles from animals of similar body weight but adapted to different levels of activity: three horses and three steers. All samples were analyzed biochemically to measure the activity of key metabolic enzymes. The skeletal muscles were analyzed histochemically for fibre type composition, fibre area and capillary supply. The general pattern of differences in fibre type composition and metabolic profile between muscle groups was similar in both horses and steers. The hearts of both species had high citrate synthase (C...
Suagee JK, Corl BA, Hulver MW, McCutcheon LJ, Geor RJ.Plasma insulin concentrations are elevated (hyperinsulinemia) in horses with obesity-associated insulin resistance. In other species, insulin resistance is partly due to reduced levels of insulin receptor and the insulin-sensitive glucose transporter, and, in vitro, chronic hyperinsulinemic conditions reduce the expression of these proteins. Consumption of grain-based concentrate feeds results in postprandial hyperinsulinemia in horses, and adaptation to these diets is associated with insulin resistance. As such, it is possible that the repeated, chronic postprandial hyperinsulinemia associate...
Palmer JL, Bertone AL, Litsky AS.Changes in contact area and pressure distribution with loading were evaluated on the proximal articulating surface of the equine third carpal bone using safranin-O dye staining and pressure sensitive film techniques. A significant increase in percentage contact area resulted as the applied load was increased from 3115 to 9000 N (54.93% +/- 7.99 vs 61.43% +/- 7.37 respectively, P = 0.016). The area in contact shifted towards the dorsal aspect of both the radial and intermediate facets of the third carpal bone. Changes were also detected in the mean pressure under the same loading conditions. Th...
Hofberger S, Gauff F, Licka T.In older horses, pituitary pars intermedia dysfunction (PPID) and suspensory ligament (SL) degeneration are common. The aim of the present study was to identify histopathological changes in the SL in horses with PPID. SLs of four horses with clinical signs of PPID (17-26 years of age) were compared with SLs from four old horses (18-31 years of age) and three young horses (4-9 years of age). In horses with PPID, there was reduced longitudinal arrangement of collagen fibres in SLs, along with inclusions of cartilage, extracellular matrix and haemorrhage, as well as significant proteoglycan accum...
Chikuni K, Muroya S, Nakajima I.Nucleotide sequences which included the full coding region for three types of myosin heavy chain (MyHC) isoforms were determined from equine skeletal muscles. The deduced amino acid sequences were 1937, 1938, and 1935 residues for the MyHC-2a, -2x, and -slow, respectively. No MyHC-2b isoform was amplified from the equine muscle cDNA except for one pseudogene fragment. One nucleotide was inserted in the coding region of the equine pseudogene product, a minute amount of which was expressed in the skeletal muscle. The 596 bp sequence of the equine MyHC pseudogene was categorized into the MyHC-2b ...
Nagy A, Dyson S.While low-field magnetic resonance (MR) images can provide useful information in the investigation of proximal metacarpal region pain, an in-depth knowledge of anatomy and comparison with more detailed high-field images are essential to understand the meaning of different signal intensities within tissues. This anatomic description is based on low-field and high-field MR examination of 30 cadaver metacarpal regions of mature horses with no history of carpal or proximal metacarpal pain. Normal MR anatomy is described and is illustrated by high-field and low-field MR images in transverse, sagitt...
Bolwell CF, Rogers CW, French NP, Firth EC.To quantify the time from the start of training to the first interruption and to identify horse and training risk factors for voluntary interruptions and interruptions due to musculoskeletal injury occurring before the first trial. Methods: A prospective cohort study was used to collect data on the training activity of 2-year-old racehorses, from 14 trainers in the Northern and Central Districts of New Zealand, over two racing seasons (2008/09 and 2009/10). Daily training data were recorded for each horse, including, distances worked at canter (>15 seconds/200 m), three measures of high-spe...
Firth EC, Rogers CW.This paper summarises and presents in context the main findings of an extensive series of studies of early training lasting 13 weeks in which the tissue responses of 2-year-old Thoroughbred horses were assessed using a combination of methods. Negligible clinical injury was detected and thus the study fulfilled the intention of investigating adaptive change rather than injury. Cancellous and cortical bone, some digital tendons, and articular cartilage responded to early training exercise to a greater or lesser degree. Clinical examination and ancillary diagnostic aids currently in veterinary cl...
Dunnett M, Harris RC, Orme CE.A simple, robust and reproducible analytical method for the determination of phosphocreatine (PCr), creatine (Cr) and creatinine (Cn) in equine skeletal muscle is presented. The technique used isocratic reverse-phase ion-pairing high-performance liquid chromatography. Neutralized perchloric acid extracts of equine muscle biopsies were analysed and the values obtained were compared with determinations from an established enzymic procedure. Good resolution of all three metabolites was achieved within a retention time of less than 11 min. Linearity for each metabolite within the concentration ran...
