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.
Moshage SG, McCoy AM, Polk JD, Kersh ME.Bone adaptation is in part driven by mechanical loading, and exercise during youth has been shown to have life-long benefits for bone health. However, the development of early exercise-based interventions that reduce the incidence of fractures in racing horses is limited by the lack of characterization of normal development in growing bone. Previous efforts to quantify bone development in the horse have relied on repeated radiographs or peripheral quantitative computed tomography scans, which are limited in their assessment of the entire bone. In this study, we acquired computed tomography sca...
Labens R, Schramme MC, Murray RC, Bolas N.High-field MRI of the proximal metacarpal/metatarsal region has been associated with great diagnostic potential and clinical reports of standing low-field MRI of the forelimb suggest the same. To better understand diagnostic outcomes with standing low-field MRI of the proximal suspensory region, a prospective survey study was conducted and users of a widely available system questioned on their experience, operating procedures, and interpretation of standing low-field MRI findings. Response data included scores on a modified Likert scale from which weighted ratings were calculated for statistic...
Young JM, Schoonover MJ, Kembel SL, Taylor JD, Bauck AG, Gilliam LL.To evaluate the analgesic effects of orally administered gabapentin on horses with chronic thoracic limb lameness. Methods: Randomized, crossover design. Methods: A total of 14 adult horses with chronic thoracic limb lameness. Methods: Following baseline measurement of lameness, horses were administered each of four treatments orally in grain: treatment G, gabapentin (20 mg kg) twice daily for 13 doses; treatment F, firocoxib (171 mg once, then 57 mg once daily for six doses); treatment GF, gabapentin and firocoxib at previously stated doses and frequencies; or treatment C, grain only as a con...
Ribitsch I, Gueltekin S, Keith MF, Minichmair K, Peham C, Jenner F, Egerbacher M.Aging is hypothesized to be associated with changes in tendon matrix composition which may lead to alteration of tendon material properties and hence propensity to injury. Altered gene expression may offer insights into disease pathophysiology and thus open new perspectives toward designing pathophysiology-driven therapeutics. Therefore, the current study aimed at identifying naturally occurring differences in tendon micro-morphology and gene expression of newborn, young and old horses. Age-related differences in the distribution pattern of tendon fibril thickness and in the expression of the ...
Recent advances in tendinopathy research have focused on tendon vascularization detected with Color Doppler (CD) ultrasound. The use of CD has also been described in horses in a study on chronic lesions of superficial digital flexor tendon and suspensory ligament. The aim of this study was to investigate the occurrence and distribution of power Doppler (PD) signal in horses with superficial digital flexor tendinopathy. Twenty-five horses with tendinopathy were included and 10 healthy horses with no lameness and no ultrasonographic abnormalities were used for comparison. In all horses with tend...
Farries G, Bryan K, McGivney CL, McGettigan PA, Gough KF, Browne JA, MacHugh DE, Katz LM, Hill EW.While over ten thousand genetic loci have been associated with phenotypic traits and inherited diseases in genome-wide association studies, in most cases only a relatively small proportion of the trait heritability is explained and biological mechanisms underpinning these traits have not been clearly identified. Expression quantitative trait loci (eQTL) are subsets of genomic loci shown experimentally to influence gene expression. Since gene expression is one of the primary determinants of phenotype, the identification of eQTL may reveal biologically relevant loci and provide functional links ...
Garbin LC, Olver CS.Autologous platelet-rich plasma (PRP) is a biological preparation made from the patient's own plasma that contains a platelet concentration above the whole blood baseline. Owing to the release of growth factors and other cytokines after degranulation, platelets have a central role in inflammation and in different stages of the healing process. For this reason, PRP-derived products have been used to enhance healing of musculoskeletal injuries and modulate progression of inflammatory processes, including osteoarthritis (OA). Osteoarthritis is one of the main causes of musculoskeletal disabilitie...
Sp N, Kang DY, Kim DH, Lee HG, Park YM, Kim IH, Lee HK, Cho BW, Jang KJ, Yang YM.Cortisol is a hormone involved in stress during exercise. The application of natural compounds is a new potential approach for controlling cortisol-induced stress. Tumour suppressor protein p53 is activated during cellular stress. Succinate dehydrogenase complex subunit A () and hypoxanthine phosphoribosyl transferase 1 () are considered to be two of the most stable reference genes when measuring stress during exercise in horses. In the present study cells were considered to be in a 'stressed state' if the levels of these stable genes and the highly stress responsive gene p53 were altered. It ...
Mouloodi S, Rahmanpanah H, Burvill C, Davies HMS.The hierarchical nature of bone makes it a difficult material to fully comprehend. The equine third metacarpal (MC3) bone experiences nonuniform surface strains, which are a measure of displacement induced by loads. This paper investigates the use of an artificial neural network expert system to quantify MC3 bone loading. Previous studies focused on determining the response of bone using load, bone geometry, mechanical properties, and constraints as input parameters. This is referred to as a forward problem and is generally solved using numerical techniques such as finite element analysis (FEA...
Roth SP, Brehm W, Groß C, Scheibe P, Schubert S, Burk J.Transforming growth factor beta 3 (TGFβ3) promotes tenogenic differentiation and may enhance tendon regeneration in vivo. This study aimed to apply TGFβ3 absorbed in decellularized equine superficial digital flexor tendon scaffolds, and to investigate the bioactivity of scaffold-associated TGFβ3 in an in vitro model. TGFβ3 could effectively be loaded onto tendon scaffolds so that at least 88% of the applied TGFβ3 were not detected in the rinsing fluid of the TGFβ3-loaded scaffolds. Equine adipose tissue-derived multipotent mesenchymal stromal cells (MSC) were then seeded on scaffolds loa...
Camargo Garbin L, McIlwraith CW, Frisbie DD.Platelet-rich plasma (PRP) as well as other platelet-derived products have been used as a potential disease-modifying treatment for musculoskeletal diseases, such as osteoarthritis (OA). The restorative properties of such products rely mainly on the high concentrations of growth factors, demonstrating encouraging results experimentally and clinically. Yet, the autologous blood-derived nature of the PRP product lead to limitations that precludes it's widespread use. The main limitations for PRP use are; product variability, the need for minimum laboratory settings in most cases, and the need fo...
Merrifield-Jones M, Tabor G, Williams J.Back pain is a significant factor for horses and is challenging for professionals to diagnose, with assessment frequently using subjective tools such as manual palpation. Reliable and valid objective measures are required and use of a pressure algometer (PA) has been investigated as an assessment tool; however, it has limitations, and other more realistic methods may be better suited for the task. The aim of the study was to establish inter- and intra-rater reliability for PA, FlexiForce Sensor (FFS), and manual palpation for equine epaxial soft tissue, measuring mechanical nociception thresho...
Noguera Cender A, Mählman K, Lischer CJ.To describe and evaluate an alternative technique for tenoscopic resection of the manica flexoria (MF). Methods: Descriptive study. Methods: Equine cadaver forelimbs and hind limbs (n = 36). Methods: Three surgeons varying in experience resected the MF in 12 limbs. The procedure was divided into six steps, including resection of the lateral/medial borders of the MF with a hook knife and resection of the proximal border with a micro scalpel. Outcomes compared between surgeons included completeness of resection, appearance of the margins of resection, appearance of the resected MF, collateral da...
Cercone M, Olsen E, Perkins JD, Cheetham J, Mitchell LM, Ducharme NG.Exercise induced intermittent dorsal displacement of the soft palate (DDSP) is a common cause of airway obstruction and poor performance in racehorses. The definite etiology is still unclear, but through an experimental model, a role in the development of this condition was identified in the dysfunction of the thyro-hyoid muscles. The present study aimed to elucidate the nature of this dysfunction by investigating the spontaneous response to exercise of the thyro-hyoid muscles in racehorses with naturally occurring DDSP. Intramuscular electrodes were implanted in the thyro-hyoid muscles of nin...
Gonzalez ML, Jacobs RD, Ely KM, Johnson SE.Postexercise skeletal muscle repair is dependent on the actions of satellite cells (SCs). The signal(s) responsible for activation of these normally quiescent cells in the horse remain unknown. The objective of the experiment was to determine whether submaximal exercise or tributyrin (TB) supplementation is sufficient to stimulate SC activation. Adult geldings were fed a control diet (n = 6) or a diet containing 0.45% TB (n = 6). After 30 d, the geldings performed a single bout of submaximal exercise. Middle gluteal muscle biopsies and blood were collected on days -1, 1, 3, and 5 relative to e...
MacKechnie-Guire R, MacKechnie-Guire E, Fairfax V, Fisher D, Fisher M, Pfau T.This study evaluated the effect of saddle tree width on thoracolumbar and limb kinematics, saddle pressure distribution, and thoracolumbar epaxial musculature dimensions. Correctly fitted saddles were fitted by a Society of Master Saddler Qualified Saddle Fitter in fourteen sports horses (mean ± SD age 12 ± 8.77 years, height 1.65 ± 0.94 m), and were altered to one width fitting wider and narrower. Horses were equipped with skin markers, inertial measurement units, and a pressure mat beneath the saddle. Differences in saddle pressure distribution, as well as limb and thoracolumbosacral kine...
Ginés-Díaz A, Martínez-Romero MT, Cejudo A, Aparicio-Sarmiento A, Sainz de Baranda P.Previous research has analyzed how the sport influences sagittal spinal curvatures in young athletes and has found that spinal curves may be modified as a consequence of repeated movement patterns and postures of each discipline. Objective: To analyze sagittal spinal alignment by equestrian discipline and its relation to training load, and to describe "sagittal integrative morphotype" in young riders. Methods: Observational descriptive study. Methods: Training room. Methods: A total of 23 riders (aged 9-17 y)-13 dressage riders (3 males and 10 females) and 10 show jumping riders (5 males and ...
Chen JW, Stefanovski D, Haughan J, Jiang Z, Boston R, Soma LR, Robinson MA.Extracorporeal shockwave therapy (ESWT) can potentially mask painful injuries in equine athletes. Tests to detect whether a horse has received ESWT prior to competition are needed. Extracorporeal shockwave therapy is known to affect inflammatory mediators in other species, and if these mediators are altered in the horse, these could serve as biomarkers of ESWT. Objective: To test the hypothesis that a single application of ESWT will alter the circulating protein concentrations of 10 inflammatory mediators in horse plasma. Methods: Prospective repeated measures experimental study. Methods: Elev...
Hybridization has been widely practiced in plant and animal breeding as a means to enhance the quality and fitness of the organisms. In domestic equids, this hybrid vigor takes the form of improved physical and physiological characteristics, notably for strength or endurance. Because the offspring of horse and donkey is generally sterile, this widely recognized vigor is expressed in the first generation (F1). However, in the absence of recombination between the two parental genomes, F1 hybrids can be expected to be phenotypically intermediate between their parents which could potentially restr...
Bellone RR, Ocampo NR, Hughes SS, Le V, Arthur R, Finno CJ, Penedo MCT.Catastrophic fractures are among the most common cause of fatalities in racehorses. Several factors, including genetics, likely contribute to increased risk for fatal injuries. A variant in the procollagen-lysine, 2-oxoglutarate 5-dioxygenase1 gene (PLOD1 c.2032G>A) was shown to cause Warmblood fragile foal syndrome type 1 (WFFS), a fatal recessive defect of the connective tissue. Screening of multiple horse breeds identified the presence of the WFFS allele in the Thoroughbred. PLOD1 is involved in cross-linking of collagen fibrils and thus could potentially increase the risk of catastrophic b...
Clayton HM, Hobbs SJ.Gaits are typically classified as walking or running based on kinematics, the shape of the vertical ground reaction force (GRF) curve, and the use of inverted pendulum or spring-mass mechanics during the stance phase. The objectives of this review were to describe the biomechanical characteristics that differentiate walking and running gaits, then apply these criteria to classify and compare the enhanced natural gait of collected trot with the artificial gaits of passage and piaffe as performed by highly trained dressage horses. Limb contact and lift off times were used to determine contact se...
Seghrouchni M, Elkasraoui H, Piro M, Alyakine H, Bouayad H, Chakir J, Tligui N, Elallali K, Azrib R.Tbourida is a traditional Moroccan equestrian sport in which 15 horses gallop 200 m in a line while riders fire into the sky with muskets. The stop is the finale and representative demands of this equestrian event. Such particular sudden stop after a fast gallop requires a hyperextension of the metacarpophalangeal joint. Indeed, it is well known that Tbourida show predisposes horses to different injuries of the hard and soft tissues of the distal forelimbs. Yet, there is a paucity of research that examined such lesions. The aim of the present study was to investigate for the first time the typ...
Johnson S, Symons J.Equine athletes can incur musculoskeletal injuries due to repetitive loading during training and competition. Prior to signs of lameness, horse trainers and veterinarians may observe swelling in the distal limbs, where injuries most frequently occur. Early observations may guide modulation of training to manage physiological stress and mitigate risk of injury. However, these observations of changing limb volume can be subjective and imprecise. The aim of this study was to assess the accuracy and applicability of a tablet-mounted, 3D scanner to measure and record distal limb volumes of horses b...
Legg KA, Colborne GR, Gee EK, Rogers CW.To evaluate the elastic modulus of various ligaments of the forelimbs of cadaveric horses. Methods: 408 ligaments from 37 forelimbs of 10 Thoroughbred cadavers and cadavers of 9 other horse breeds. Methods: Collateral ligaments and straight and oblique sesamoid ligaments were harvested from the proximal interphalangeal, metacarpophalangeal, carpal, and elbow joints of both forelimbs of all 19 horses. Ligament dimensions were measured, and the elastic modulus was determined by tensile testing the ligaments with a strain rate of 1 mm•s. Results: Elastic modulus of the ligaments differed signif...
Haussler KK, Pool RR, Clayton HM.The objectives of this observational, cross-sectional study were to characterize and establish the prevalence of osseous proliferation of articular surfaces, joint margins and adjacent soft tissue attachments (i.e., joint capsule and deep spinal muscles) in a mixed population of horses of variable ages, sizes, and breeds to better capture the full spectrum of disease affecting the cervical articular processes. Cranial and caudal articular processes of the cervical and first three thoracic vertebrae (C2-T3) from 55 horses without a primary complaint of neck pain were evaluated for the presence ...
Kemper AM, Drnevich J, McCue ME, McCoy AM.Skeletogenesis is complex and incompletely understood. Derangement of this process likely underlies developmental skeletal pathologies. Examination of tissue-specific gene expression may help elucidate novel skeletal developmental pathways that could contribute to disease risk. Our aim was to identify and functionally annotate differentially expressed genes in equine neonatal and adult articular cartilage (AC) and subchondral bone (SCB). RNA was sequenced from healthy AC and SCB from the fetlock, hock, and stifle joints of 6 foals (≤4 weeks of age) and six adults (8-12 years of age). There w...
To evaluate the etiology of skeletal changes noted in equid vertebrae from a 19- century context near Belgrade, Serbia. A vertebral column consisting of 15 fused thoracic vertebrae (T2-T16), with right ribs fused to T4 and T5 and small remnants of ribs articulating with T4, T5 and T6 on the left side were accidentally recovered during industrial exploitation of sand. The specimen was subjected to morphological analysis and collagen fingerprinting by mass spectrometry for species identification. In order to determine the absolute temporal context, radiocarbon dating was employed. Pathological c...
Self ZT, Spence AJ, Wilson AM.We used a radio tracking system to examine the speed of 373 racehorses on different gradients on an undulating racecourse during 33 races, each lasting a few minutes. Horses show a speed detriment on inclines (0.68 m · s(-1) · 1% gradient(-1), r(2) = 0.97), the magnitude of which corresponds to trading off the metabolic cost (power) of height gain with the metabolic cost (power) of horizontal galloping. A similar relationship can be derived from published data for human runners. The horses, however, were also slower on the decline (-0.45 m · s(-1) · 1% gradient(-1), r(2) = 0.92). Human ath...
Wickler SJ, Greene HM, Egan K, Astudillo A, Dutto DJ, Hoyt DF.The relationship between fatigue and stride and/or muscle stiffness requires further study. Objective: To measure stride parameters in horses undergoing fatigue associated with running at submaximal speeds both on a treadmill and in an endurance ride. Objective: Stride frequencies and estimates of hindlimb stiffness would be decreased in fatigued horses. Methods: Horses were fatigued using 2 paradigms: run to exhaustion at a treadmill (4.5 m/sec, 6% incline) and finishing an 80 km endurance ride. Videos were digitised before and after fatigue and analysed for stride parameters: hind limb lengt...
Miyata H, Itoh R, Sato F, Takebe N, Hada T, Tozaki T.Variants of the Myostatin gene have been shown to have an influence on muscle hypertrophy phenotypes in a wide range of mammalian species. Recently, a Thoroughbred horse with a C-Allele at the g.66493737C/T single-nucleotide polymorphism (SNP) has been reported to be suited to short-distance racing. In this study, we examined the effect of the Myostatin SNP on muscle fiber properties in young Thoroughbred horses during a training period. To investigate the effect of the Myostatin SNP on muscle fiber before training, several mRNA expressions were relatively quantified in biopsy samples from the...
Riemersma DJ, van den Bogert AJ, Jansen MO, Schamhardt HC.Strains in the tendons of the m. flexor digitalis superficialis (superficial digital flexor, SDFT) and m. flexor digitalis profundus (deep digital flexor, DDFT) tendons, the accessory ligament of the deep digital flexor muscle (inferior check ligament, ICL) and the m. interosseus medius (suspensory ligament, SL) of 5 ponies were recorded at the walk and trot using mercury-in-silastic strain gauges (MISS), on a hard surface (brick pavement) and on sand. The horses were shod with normal, flat shoes. On pavement, strain in the SDFT, DDFT and SL increased significantly from the walk (2.19%, 1.15% ...
Gellman K, Ruina A.Horses stand for most of each day. Although they can use various leg configurations (postures), they usually stand with vertical legs. Why? We addressed this question with a 2D quasi-static model having three rigid parts: a trunk, massless fore-limbs and massless rear limbs, with hinges at the shoulders, hips, and hooves. The postural parameter we varied was ℓg, the distance between the hooves. For a given ℓg, statics finds an equilibrium configuration which, with no muscle stabilization (i.e. using minimal effort) is unstable. We assume a horse uses that configuration. To measure the neur...
Van Harreveld PD, Lillich JD, Kawcak CE, Gaughan EM, Mclaughlin RM, Debowes RM.To evaluate clinical effects of immobilization followed by remobilization and exercise on the metacarpophalangeal joint (MPJ) in horses. Methods: 5 healthy horses. Methods: After lameness, radiographic, and force plate examinations to determine musculoskeletal health, 1 forelimb of each horse was immobilized in a fiberglass cast for 7 weeks, followed by cast removal and increasing amounts of exercise, beginning with hand-walking and ending with treadmill exercise. Lameness examination, arthrocentesis of both MPJ, single-emulsion radiographic examination, nuclear scintigraphic examination, grou...
Mendoza L, Lejeune JP, Caudron I, Detilleux J, Sandersen C, Deliège B, Serteyn D.Osteochondrosis dissecans (OCD) is a developmental orthopedic disease caused by a failure of the endochondral ossification in epiphyseal plates and joint cartilage. This trouble may induce the presence of osteochondral fragments in the articulation, fissures or subchondral bone cysts in the growth cartilage. Occurrence of osteochondrosis is influenced by a complex interaction of different factors. Among these, the effect of the housing and the feeding of the foals during their first months of life, have been described as risk factors for the development of osteochondrosis. The aim of this stud...
Watanabe T, Imamura Y, Suzuki D, Hosaka Y, Ueda H, Hiramatsu K, Takehana K.The equine superficial digital flexor tendon (SDFT) has a graded distribution of collagen fibril diameters, with predominantly small-diameter fibrils in the region of the myotendinous junction (MTJ), a gradual increase in large-diameter fibrils toward the osteotendinous junction (OTJ), and a mixture of small- and large-diameter fibrils in the middle metacarpal (MM) region. In this study, we investigated the ultrastructure of the SDFT, to correlate the spatial relationship of the collagen fibrils with the graded distribution. The surface-to-surface distances of pairs of fibrils were found to be...
Roepstorff L, Wiestner T, Weishaupt MA, Egenvall E.The aim of this study was to compare an inertial motion system (IMS) to an optical based locomotion analysis system measuring limb sagittal segment angles in horses at the walk and trot. The metatarsal/metacarpal bones of two horses (20 trials) were fitted with optical system markers and an IMS. Between the systems, measuring range of motion (ROM) of the sagittal metatarsal/metacarpal bone angles, the IMS measured higher ROM than the optical system (bias 1.6°; precision at 1.96 standard deviation 1.9°). The same angle data were used to assess inter-limb symmetry by calculating phase shift be...
Barrey E.A greater knowledge of the biomechanics is necessary in equine orthopaedics, therapeutics, farriery and for the selection of athletic horses. The purpose of this study was to determine the normal distribution of the vertical component of the hoof force using a measuring boot. The measurements were carried out using 20 sound horses walking and trotting on a straight hard track. A force measuring horseshoe, attached to the foot with a boot, provided continuous recording of vertical forces at four locations on the hoof. For each measuring location, a computer program produced curves and calculate...
Haussler KK, Martin CE, Hill AE.Spinal mobilisation and spinal manipulative therapy (SMT) are being applied to horses; however, there are limited objective measures of their effects on spinal mobility or stiffness in actively ridden horses. Objective: To quantify passive spinal movements induced during dorsoventral mobilisation of the trunk and to identify any potential effects of SMT on measures of spinal mobility within the thoracolumbar region in standing horses. We hypothesise that displacement amplitudes will be significantly increased across vertebral levels after SMT, compared to spinal mobilisation only within the co...
Symons JE, Garcia TC, Stover SM.The effect of racetrack surface (dirt or synthetic) on distal hindlimb kinematics of racehorses running at competition speeds is not known. Objective: To compare distal hindlimb and hoof kinematics during stance of breezing (unrestrained gallop) racehorses between dirt and synthetic surfaces. Methods: Two-dimensional kinematic video analysis of 5 Thoroughbred racehorses galloping at high speeds (12-17 m/s) on a dirt racetrack and a synthetic racetrack. Methods: The positions of kinematic markers applied to the left hindlimb were recorded at 500 Hz. Position, velocity and acceleration of jo...
Ropka-Molik K, Stefaniuk-Szmukier M, Piórkowska K, Szmatoła T, Bugno-Poniewierska M.Apoptosis plays an important role in the regulation of healthy tissue growth and development as well as in controlling the maintenance of homeostasis in exercising muscles. During an intensive physical effort, the regulation of cell death by apoptosis results in the replacement of unaccustomed muscle cells by new cells that are better suited to exercise. The aim of this study was to determine the expression of two genes (SH3FR1 and SH3RF2) that control apoptosis in muscle tissues during training periods characterized by different intensities. The gene expression levels were estimated using rea...
Martig S, Hitchens PL, Stevenson MA, Whitton RC.The repetitive large loads generated during high-speed training and racing commonly cause subchondral bone injuries in the metacarpal condyles of racehorses. Adaptive bone modelling leads to focal sclerosis at the site of highest loading in the palmar aspect of the metacarpal condyles. Information on whether and how adaptive modelling of subchondral bone changes during the career of a racehorse is sparse. The aim of this cross-sectional study was to describe the changes in subchondral bone micromorphology in the area of highest loading in the palmar aspect of the metacarpal condyle in thorough...
Swanberg JE, Clouser JM, Westneat SC, Marsh MW, Reed DB.Animal production is a dangerous industry and increasingly reliant on a Latino workforce. Within animal production, little is known about the risks or the occupational hazards of working on farms involved in various aspects of thoroughbred horse breeding. Extant research suggests that horse workers are at risk of musculoskeletal and respiratory symptoms, kicks, and other injuries. However, limited known research has examined the experiences of the industry's workers, including immigrant workers, despite their prominence and increased vulnerability. Using data collected from thoroughbred farm r...
Mascarello F, Veggetti A.The intrinsic laryngeal muscles of the horse, donkey, sheep, ox, pig, dog and cat were examined for myosin ATPase, following acid and alkali pre-incubation, SDH and M-alphaGPDH activities. In all laryngeal muscles two fibre types, betaR and alphaR, belonging to slow and fast-contracting, fatigue-resistant motor units (types S and FR) were present in different proportions. The alphaW fibre type, belonging to fast-contracting and fatigue-resistant motor units was absent (type FF). The alphaR fibres of the dog and the cat were subdivided into groups by the various degrees of acid stable myosin AT...
White-Lewis S, Johnson R, Ye S, Russell C.To compare equine-assisted therapy to exercise education on pain, range of motion, and quality of life in adults and older adults with arthritis. Quality of life for adults and older adults is negatively impacted by arthritis pain, stiffness, and decreased function. Equine-assisted therapy provides unique movements to the rider's joints and muscles improving pain, range of motion, and quality of life and has improved outcomes in balance, gait, strength, functional mobility, and spasticity for older adults, stroke, spinal cord injury, and multiple sclerosis patients. No research has investigate...
Brown MP, Trumble TN, Plaas AH, Sandy JD, Romano M, Hernandez J, Merritt KA.(1) To investigate the effects of exercise and osteochondral (OC) injury on synovial fluid (SF) chondroitin sulfate (CS) and hyaluronan (HA) concentration and chain length, (2) to compare SF and cartilage CS data from joints with OC fragmentation, and (3) to compare SF CS and HA profiles with those seen in serum from the same horses. Methods: Serum and SF were obtained from (1) normal horses after 8 weeks rest, (2) the same horses after 9 months treadmill training, and (3) horses with OC injury from racing. Articular cartilage was also collected from group 3 horses. Concentrations and chain le...
Holmström M, Fredricson I, Drevemo S.Trot in hand, working trot, collected trot, passage and piaffe of 6 Grand Prix dressage horses were recorded by high speed film (250 frames/s). Angular patterns and hoof trajectories of the left fore- and hindlimbs were analysed and presented as mean and standard deviation (s.d.) curves. Speed and stride length decreased and fore- and hind stance phase durations increased with collection resulting in no suspension in piaffe. The diagonal advanced placement was positive in all gaits except for piaffe. Most of the changes in forelimb angular patterns were effects of reduction in forelimb pendula...
García Liñeiro JA, Graziotti GH, Rodríguez Menéndez JM, Ríos CM, Affricano NO, Victorica CL.The multifidus muscle fascicles of horses attach to vertebral spinous processes after crossing between one to six metameres. The fascicles within one or two metameres are difficult to distinguish in horses. A vertebral motion segment is anatomically formed by two adjacent vertebrae and the interposed soft tissue structures, and excessive mobility of a vertebral motion segment frequently causes osteoarthropathies in sport horses. The importance of the equine multifidus muscle as a vertebral motion segment stabilizer has been demonstrated; however, there is scant documentation of the structure a...
Bentley VA, Sample SJ, Livesey MA, Scollay MC, Radtke CL, Frank JD, Kalscheur VL, Muir P.Failure of functional adaptation to protect the skeleton from damage is common and is often associated with targeted remodeling of bone microdamage. Horses provide a suitable model for studying loading-related skeletal disease because horses are physically active, their exercise is usually regulated, and adaptive failure of various skeletal sites is common. We performed a histologic study of the navicular bone of three groups of horses: (1) young racing Thoroughbreds (n = 10); (2) young unshod ponies (n = 10); and (3) older horses with navicular syndrome (n = 6). Navicular syndrome is a painfu...
Maleas G, Mageed M.This retrospective study aimed to evaluate the clinical effect of bone marrow aspirate concentrate (BMAC) and leukocyte rich PRP (LR-PRP) compared to horses undergoing controlled exercise alone in horses with >3 months proximal suspensory desmopathy in hindlimbs (HPSD). Nighty-three horses were divided into three groups according to the treatment: a control (n = 22), LR-PRP (n = 46), and BMAC (n = 25) group. Lameness and ultrasound scores were recorded before treatment (T0) and at 6 months (T1) post-treatment. Records horses considered sound at evaluation and level of performance were addition...
Valberg SJ, McKenzie EC, Eyrich LV, Shivers J, Barnes NE, Finno CJ.Although exertional rhabdomyolysis (ER) is common in Arabian horses, there are no dedicated studies describing histopathological characteristics of muscle from Arabian horses with ER. Objective: To prospectively identify distinctive histopathological features of muscle from Arabian endurance horses with a history of ER (pro-ER) and to retrospectively determine their prevalence in archived samples from Arabian horses with exertional myopathies (retro-ER). Methods: Prospective and retrospective histopathological description. Methods: Middle gluteal muscle biopsies obtained from Arabian controls ...
Gillis C, Sharkey N, Stover SM, Pool RR, Meagher DM, Willits N.Results of studies in human beings and other species have indicated that aging significantly influences the strength, modulus of elasticity, and energy storage ability of tendon. We wanted to determine the effects of aging on the material and ultrasonographic properties of equine superficial digital flexor (SDF) tendon. Ultrasonographic measurements of left forelimb SDF tendon cross-sectional area and mean echogenicity were made in 23 standing horses ranging in age from 2 to 23 years. All horses had not been in work for a minimum of 6 months prior to the study. After euthanasia, left forelimb ...
Rhee HS, Steel CM, Derksen FJ, Robinson NE, Hoh JF.We used immunohistochemistry to examine myosin heavy-chain (MyHC)-based fiber-type profiles of the right and left cricoarytenoideus dorsalis (CAD) and arytenoideus transversus (TrA) muscles of six horses without laryngoscopic evidence of recurrent laryngeal neuropathy (RLN). Results showed that CAD and TrA muscles have the same slow, 2a, and 2x fibers as equine limb muscles, but not the faster contracting fibers expressing extraocular and 2B MyHCs found in laryngeal muscles of small mammals. Muscles from three horses showed fiber-type grouping bilaterally in the TrA muscles, but only in the le...
Martig S, Hitchens PL, Lee PVS, Whitton RC.Subchondral bone injuries often precede articular cartilage damage in osteoarthritis and are common in thoroughbred racehorses due to the accumulation of fatigue damage from high speed racing and training. Thus, racehorses provide a model to investigate the role of subchondral bone in joint disease. We assessed the association of horse and racing related factors and micro-CT based micromorphology of three separate subchondral bone layers with the initial stiffness and compressive fatigue life of bone plugs. Furthermore, we investigated three different definitions of fatigue failure of subchond...
Bobbert MF, Santamaría S.The purpose of the present study was to gain more insight into the contribution of the forelimbs and hindlimbs of the horse to energy changes during the push-off for a jump. For this purpose, we collected kinematic data at 240 Hz from 23 5-year-old Warmbloods (average mass: 595 kg) performing free jumps over a 1.15 m high fence. From these data, we calculated the changes in mechanical energy and the changes in limb length and joint angles. The force carried by the forelimbs and the amount of energy stored was estimated from the distance between elbow and hoof, assuming that this part of the le...
Lee H, Kirkland WG, Whitmore RN, Theis KM, Young HE, Richardson AJ, Jackson RL, Hanson RR.Thicknesses of fresh equine articular cartilage surfaces from the fetlock, carpal and stifle joints were measured employing a needle probe test. Methods: Eighty-seven samples used in measurement were cultivated from fetlock, carpal and stifle joints of 12 deceased within 4 h of death. After approximately three minutes of exposure to air during dissection, all cartilage samples were preserved in a saline solution to keep the articular cartilage hydrated for testing. The thickness was measured on five different spots on the same sample. The thicknesses of the fetlock, carpus and stifle were co...
Haussler KK, Manchon PT, Donnell JR, Frisbie DD.Low-level laser therapy has been used clinically to treat musculoskeletal pain; however, there is limited evidence available to support its use in treating back pain in horses. The objective of this study was to evaluate the clinical effectiveness of low-level laser therapy and chiropractic care in treating thoracolumbar pain in competitive western performance horses. The subjects included 61 Quarter Horses actively involved in national western performance competitions judged to have back pain. A randomized, clinical trial was conducted by assigning affected horses to either laser therapy, chi...
Fowlie JG, Arnoczky SP, Stick JA, Pease AP.By study of the translocation and deformation of equine menisci throughout the range of motion, it may be possible to identify potential mechanical factors in the pathogenesis of injury to the cranial horn of the medial meniscus. Objective: To quantitatively document meniscal translocation and deformation using radiographic and MR imaging, and to evaluate for potential variation between the medial and lateral menisci. Methods: Radiographic markers were embedded in the periphery of the menisci in 6 cadaver stifles. Proximal-distal radiographs were taken at 15° intervals ranging from full flexi...
