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.
Takahashi Y, Takahashi T, Mukai K, Ebisuda Y, Ohmura H.Understanding how muscle activity changes with different surface grades during canter is essential for developing training protocols in Thoroughbreds because canter is their primary gait in training and races. We measured the spatiotemporal parameters and the activation of 12 surface muscles in the leading limb side of 7 Thoroughbreds. Horses were equipped with hoof strain gauges and cantered at 10 m/s on a treadmill set to grades of -4%, 0%, 4%, and 8%, randomly, for 30 seconds each without a lead change. Integrated electromyography (iEMG) values during stance and swing phases were calculated...
Tamura N, Yoshihara E, Seki K, Mae N, Kodaira K, Iimori M, Yamazaki Y, Mita H, Urayama S, Kuroda T, Ohta M, Kasashima Y.The potential value of hypervascularity detected with power Doppler ultrasonography (PDU) within equine superficial digital flexor tendon (SDFT) as a prognostic factor of SDFT injury is not clear. The purpose of this study was to test the hypothesis that hypervascularity within SDFT is one of the risk factors for subsequent severe SDFT injury and to evaluate the prognostic value. A prospective cohort study of 97 Thoroughbred racehorses without any clinical signs of SDFT injury was conducted. Six variables of age, body weight, sex, the cross-sectional area of SDFT, PDU signal within SDFT and ex...
Renaudin C, Wensley F, Morgan J, Cassano J, Spriet M.Fetal age in Quarter Horses can be predicted within 2 weeks from 100- to 200- days of gestation using femur length, biparietal diameter (cranium diameter) and eye approximated volume. However, as pregnancy advances, the femur and cranium become too large to be imaged in their entirety using ultrasound and the corresponding biometric parameters can no longer be measured. In this longitudinal study, the proximal phalanx (P1) was evaluated as a novel biometric parameter for late gestation to predict fetal age and bone maturation. Transrectal ultrasound was performed in ten pregnant mares with kno...
Dubuc J, Schneider MJ, Dubuc V, Richard H, Pinsard M, Bancelin S, Legare F, Girard C, Laverty S.Investigate meniscal extracellular matrix degradation. Equine menisci ( = 34 from 17 horses) were studied. Site-matched sections were cut and scored from three regions (ROIs; = 102) and stained for histology, proteoglycan (safranin O and fast green), aggrecan, and collagen cleavage (NITEGE, DIPEN, and C1,2C antibodies, respectively). Picrosirius red and second harmonic generation microscopy were performed to investigate collagen ultrastructure. A total of 42 ROIs met the inclusion criteria and were included in the final analysis. The median (range) ROI histological score was 3 (0-9), providin...
van Veggel ECS, Vanderperren K, Selberg KT, Bergman HJ, Hoogelander B.This study evaluates the change in an MRI of the proximal metacarpal region in a group of sport horses that returned to work. This retrospective analysis evaluated 18 limbs represented by 17 horses. Results: The hyperintense signal within the dorsal collagenous part of the proximal suspensory ligament (PSL) on T1W/T2*W GRE sequences decreased or stayed the same in the majority of cases. The hyperintense STIR signal within the dorsal collagenous part of the PSL resolved in the majority of the patients, and the third metacarpal bone (McIII) hyperintense STIR signal resolved in all patients. The ...
Schumacher A, Gehlen H.This literature review analyzes the historical development of polo, its organizational structure, the course of the game, as well as the breeding, rearing, and training practices of polo horses. Frequently occurring ailments, such as musculoskeletal injuries, respiratory diseases, and internal illnesses, are highlighted. Lameness is a major problem, with injuries to the superficial digital flexor tendon being the most common cause. Other notable diseases include exercise-induced pulmonary hemorrhage (EIPH), myositis, rhabdomyolysis, and equine infectious anemia (EIA). To ensure the welfare of ...
Faulkner JE, Joostens Z, Broeckx BJG, Hauspie S, Mariën T, Vanderperren K.Sagittal groove disease of the proximal phalanx in equine athletes is commonly considered a bone stress injury. Repetitive hyperextension of the fetlock under high load is thought to contribute to its development. Concurrent changes are often reported in the dorsal sagittal ridge of the third metacarpus/metatarsus (MC3/MT3). Objective: To describe the spectrum of associated osseous abnormalities that are present in the fetlock in a large group of horses diagnosed with sagittal groove disease on low-field magnetic resonance imaging (MRI). Methods: Retrospective, cross-sectional. Methods: MRI im...
de Souza AF, Pereira CAM, Costa C, Fürst A, Kümmerle JM, De Zoppa ALV. The aim of this study was to measure the mechanical properties and failure mode of an model of proximal interphalangeal arthrodesis in horses with different methods of proximal screw fixation using a locking compression plate. Methods: Pastern joint arthrodesis with a 3-hole 4.5-mm narrow locking compression plate was performed on 20 forelimbs of equine cadavers, randomized into four groups based on the fixation method and type of proximal screw used: unicortical cortex, bicortical cortex, unicortical locking, bicortical locking. Single-cycle axial compression testing was conducted unti...
Dyson S, Zheng S, Aleman M.Detailed descriptions of clinical signs associated with radiological findings of the caudal cervical vertebral column are not available. Objective: Describe the clinical features associated with neck pain or stiffness, neck-related thoracic limb lameness, proprioceptive ataxia consistent with a cervicothoracic spinal cord or nerve lesion, and their frequency of occurrence compared with control horses. Methods: A total of 223 Warmblood horses. Methods: Case-control study. Controls and cases were recruited prospectively. All horses underwent predetermined lameness and neurologic examinations. Th...
Borowska M, Lipowicz P, Daunoravičienė K, Turek B, Jasiński T, Pauk J, Domino M.The paranasal sinuses, a bilaterally symmetrical system of eight air-filled cavities, represent one of the most complex parts of the equine body. This study aimed to extract morphometric measures from computed tomography (CT) images of the equine head and to implement a clustering analysis for the computer-aided identification of age-related variations. Heads of 18 cadaver horses, aged 2-25 years, were CT-imaged and segmented to extract their volume, surface area, and relative density from the frontal sinus (FS), dorsal conchal sinus (DCS), ventral conchal sinus (VCS), rostral maxillary sinus ...
Henderson CS, Story MR, Nout-Lomas YS.To determine reasons for horses to have neck radiographs performed, the incidence of transposition of the ventral lamina of C6 onto C7 (TC67), and the final diagnoses for all horses. Our hypotheses were to find a similar incidence of TC67, as has been previously reported, and an increased incidence of neck pain and dysfunction in horses with TC67. Methods: 135 horses. Methods: Retrospective observational study. Medical records of 135 horses with cervical vertebral column radiographs between 2020 and 2022 were assessed. Patient signalment, reasons for radiographs, radiographic findings, and dia...
Zalig V, Vengust M, Blagus R, Berner D, Sandow C, Hanna A, Miklavcic M.Lameness originating from the distal limb is common in sport horses and can vary depending on the dynamics of movement and the surface, with differences in shoeing exacerbating this variability. Driving horses work primarily on hard surfaces (pavement), whereas dressage horses work primarily on soft surfaces (riding arenas with sand). Driving horses are traditionally shod with small fixed studs made of hard metal, which are attached to the horseshoe at 4 points, while dressage horses are shod with a simple horseshoe. We investigated the hypothesis that there is a difference in the pathological...
Nawrot K, Soroko-Dubrovina M, Zielińska P, Dudek K, Howell K.The study aimed to evaluate the impact of BEMER (Physical Vascular Therapy) on body surface temperature using infrared thermography (IRT) in the distal parts of the forelimbs in Thoroughbreds. The study tested the hypothesis that BEMER therapy leads to an increase in body surface temperature and blood vessel diameter in the distal parts of the forelimbs. The study involved 16 horses, split into 2 groups: active BEMER ( = 8) and sham ( = 8). The active BEMER group had BEMER boots applied to the distal parts of the forelimbs, whereas the sham group had BEMER boots applied without activation of t...
Argüelles D, Saitua A, Miraz R, Calle-González N, Requena F, Nocera I, Vitale V, Sgorbini M, Muñoz A.It has been reported that capacitive resistive electric transfer (CRET) increases blood circulation, hemoglobin oxygenation and temperature in muscles. The attributed benefits of these changes have been linked to improved athletic performance, enhanced muscle flexibility and fastening recovery from exercise-induced fatigue. For all of this, the present research aims to investigate whether the application of CRET 24 h before exercise affects the accelerometric pattern in horses during exercise. Six sound Standardbred trotters were subjected to a CRET session of 40 min of duration, applied on ...
Wadbled L, Finck C, Santschi EM, Morehead JP, Fogarty U, Lemirre T, Beauchamp G, Richard H, Laverty S.Assess femorotibial features in foals with and without medial femoral condyle (MFC) subchondral radiolucencies (SR+ and SR-). Methods: 3 independent, sequential radiographic studies were performed. Study 1 retrospectively measured femorotibial morphological parameters in repository radiographs (SR- and SR+). Study 2 qualitatively compared drawings of intercondylar notch shape in postmortem radiographs (SR-). Study 3 prospectively measured femorotibial parameters in 1-month-old foals (SR-). In studies 1 and 3, 13 morphologic parameters were measured. Limb directional asymmetry was assessed in 2...
Lang JJ, Li X, Micheler CM, Wilhelm NJ, Seidl F, Schwaiger BJ, Barnewitz D, von Eisenhart-Rothe R, Grosse CU, Burgkart R.Femoral fractures are often considered lethal for adult horses because femur osteosynthesis is still a surgical challenge. For equine femur osteosynthesis, primary stability is essential, but the detailed physiological forces occurring in the hindlimb are largely unknown. The objective of this study was to create a numerical testing environment to evaluate equine femur osteosynthesis based on physiological conditions. The study was designed as a finite element analysis (FEA) of the femur using a musculoskeletal model of the loading situation in stance. Relevant forces were determined in the mu...
Nagy A, Dyson S.There is a limited description of magnetic resonance imaging (MRI) and no information on computed tomographic (CT) findings in the fetlock of non-lame, non-racing sports horses. This study aimed to document comparative CT, MRI and radiographic findings in the metacarpophalangeal joints of showjumpers in full work. Clinical and gait assessments, low-field MRI, fan-beam CT and radiographic examinations of both metacarpophalangeal joints were performed on 31 showjumpers. Images were analysed descriptively. In most limbs (53/62, 85.5%), there were CT and MRI changes consistent with densification i...
Ducrocq M, Kamus L, Richard H, Beauchamp G, Janvier V, Laverty S.Stifle osteoarthritis (OA) lesions are most common in the medial femorotibial (MFT) compartment. Their characterisation and mapping will inform equine veterinarians towards an accurate diagnosis of OA. Objective: Investigate and map micro-CT (μCT) changes in the hyaline articular cartilage (HAC) in the medial femoral condyle (MFC) and medial tibial plateau (MTP). Methods: Ex vivo cadaveric. Methods: Stifles (n = 7 OA and 17 control [CO]) were retrieved from a tissue bank. The MFC and MFT were imaged with μCT. Regions of interest (ROIs) were cranial (MFCcr; MTPcr) and caudal (MFCca; MTPca...
Trostle SS, Kearney EM, Medoff M, Devaney S.To describe the clinical presentation, diagnosis, and treatment of a fragmented, migrating acupuncture needle near the palmar proximal interphalangeal joint (PIPJ) of a horse. Methods: A 9-year-old Warmblood cross mare. Unassigned: The mare presented for evaluation of a linear metallic foreign body on the palmar lateral aspect of the PIPJ following acupuncture treatment. The mare had a pinpoint puncture wound and sensitivity to palpation over the lateral aspect of the PIPJ region. The referring veterinarian performed radiographs and found a linear metallic foreign body near the lateral palmar ...
Yeung CC, Svensson RB, Mogensen NMB, Merkel MFR, Schjerling P, Jokipii-Utzon A, Zhang C, Carstensen H, Buhl R, Kjaer M.Physical activity can activate extracellular matrix (ECM) protein synthesis and influence the size and mechanical properties of tendon. In this study, we aimed to investigate whether different training histories of horses would influence the synthesis of collagen and other matrix proteins and alter the mechanical properties of tendon. Samples from superficial digital flexor tendon (SDFT) from horses that were either (a) currently race trained (n = 5), (b) previously race trained (n = 5) or (c) untrained (n = 4) were analysed for matrix protein abundance (mass spectrometry), collage...
Laus F, Bazzano M, Spaterna A, Laghi L, Marchegiani A.Metabolomics can allow for the comprehensive identification of metabolites within biological systems, at given time points, in physiological and pathological conditions. In the last few years, metabolomic analysis has gained popularity both in human and in veterinary medicine, showing great potential for novel applications in clinical activity. The aim of applying metabolomics in clinical practice is understanding the mechanisms underlying pathological conditions and the influence of certain stimuli (i.e., drugs, nutrition, exercise) on body systems, in the attempt of identifying biomarkers th...
Valle AP, Brown KA, Reilly P, Ciamillo SA, Davidson EJ, Stefanovski D, Stewart HL, Ortved KF.Lameness examinations are commonly performed in equine medicine. Advancements in digital technology have increased the use of video recordings for lameness assessment, however, standardization of ideal video angle is not available yielding videos of poor diagnostic quality. The objective of this study was to evaluate the effect of video angle on the subjective assessment of front limb lameness. A randomized, blinded, crossover study was performed. Six horses with and without mechanically induced forelimb solar pain were recorded using 9 video angles including horses trotting directly away and ...
Guedes JRB, Vendruscolo CP, Tokawa PKA, Carvalho AM, Johnson PJ, Faleiros RR.Postural adaptation is a prominent feature in horses affected by laminitis. Laminitis induces intense pain, especially in the forelimbs, prompting affected horses to assume a caudally displaced trunk posture, resulting in the hyperflexion of the thoracolumbar spine. This study assessed the nature and prevalence of thoracolumbar injuries in horses with chronic laminitis compared to horses without it. Sixty horses were used (thirty laminitic and thirty non-laminitic) of different athletic purposes and ages (2-20 years). The experimental protocol entailed a single assessment of horses' thoracolum...
Reis IL, Lopes B, Sousa P, Sousa AC, Caseiro AR, Mendonça CM, Santos JM, Atayde LM, Alvites RD, Maurício AC.Musculoskeletal injuries such as equine osteoarthritis, osteoarticular defects, tendonitis/desmitis, and muscular disorders are prevalent among sport horses, with a fair prognosis for returning to exercise or previous performance levels. The field of equine medicine has witnessed rapid and fruitful development, resulting in a diverse range of therapeutic options for musculoskeletal problems. Staying abreast of these advancements can be challenging, prompting the need for a comprehensive review of commonly used and recent treatments. The aim is to compile current therapeutic options for managin...
Gisler J, Chiavaccini L, Blum S, Montavon S, Spadavecchia C.Osteoarthritis is a prevalent degenerative joint disease initiating chronic pain and lameness in horses. While several objective gait analysis systems have been developed and validated to quantify lameness severity in horses, methods to evaluate whether peripheral sensitization contributes to the pain experienced are missing. Unassigned: To evaluate whether periarticular pressure pain mapping could be proposed as an auxiliary assessment tool in horses. Specific aims were to evaluate the feasibility and intra- and inter-rater reliability of pressure pain thresholds (PPT) determination at sites ...
Schöpper H, Egerbacher M.The vascularization pattern of the equine stifle joint is insufficiently described in the literature, even though there is a growing need for knowledge of the exact blood supply, as (i) arthroscopy and endoscopic surgery techniques are increasingly performed in horses and (ii) ex vivo models of menisci need nutrient supply that mimic the in vivo situation. The aim of this study was to describe the vessels involved in the stifle joint supply and the exact branching pattern of the popliteal artery. Colored latex was injected into the arteries of nine pelvic limbs of equine cadavers (n = 6) to ev...
Poochipakorn C, Sanigavatee K, Wonghanchao T, Huangsaksri O, Chanda M.Underrun heels are among the most hoof imbalances, causing poor performance in hoses. Several corrective shoeing protocols have been performed, but the outcomes have yet to be consistent. In this study, we proposed an alternative trimming protocol for managing underrun heels: strategic palmar trimming before conventional shoeing. Therefore, the current study aimed to investigate the potential of strategic palmar trimming before conventional shoeing for managing hoof imbalance in horses with underrun heels. Unassigned: Eleven affected horses were divided into control (5 horses with 14 defective...
Bierau J, Cruz AM, Koch C, Manso-Diaz G, Büttner K, Staszyk C, Röcken M.Cone-beam computed tomography (CBCT) is regarded as a convenient and suitable alternative to conventional computed tomography. However, in the horse, the quality of obtained data sets needs to be evaluated. Therefore, the aim of this study was to compare the visibility and accessibility of clinically relevant anatomical structures displayed in CBCT and conventional multidetector computed tomography (MDCT). Unassigned: Twenty-nine limbs from horses euthanized for reasons unrelated to this study were used. Native and intraarticular contrast scans of the fetlock (CBCT vs. MDCT) were performed. Th...
Nowicka B, Torres A, Polkowska I, Jackow-Nowicka J, Przewozny M, Jackow-Malinowska J.Chronic tendon and ligament diseases are commonly encountered in both athletic humans and animals, especially horses. Distal limb diseases, including suspensory ligament (SL) pathology due to anatomical, histological, and biomechanical properties, can be considered a model for tendon and ligament pathologies in humans. The appropriate selection of therapy is often crucial in optimising the healing process. One decisive factor influencing the possibility of returning to pre-disease training levels appears to be the utilisation of physical activity, including controlled movement, during the reha...
Robert C, Valette JP, Denoix JM.Electromyographic activity (EMG) was used to determine how hindlimb muscle activation patterns vary with speed and incline in the horse. EMG was recorded using surface electrodes over the gluteus medius and tensor fasciae latae muscles during treadmill locomotion at trot for different combinations of speed (3.5 to 6 m/s) and inclination (0, 3 and 6%). Raw EMG signals were processed to determine stride duration, activity onset and end, and integrated EMG (IEMG). Stride and stance phase duration decreased linearly with increasing speed. Stride duration was not influenced by the slope. Onset and ...
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.
Turley SM, Thambyah A, Riggs CM, Firth EC, Broom ND.The palmar aspect of the third metacarpal (MC3) condyle of equine athletes is known to be subjected to repetitive overloading that can lead to the accumulation of joint tissue damage, degeneration, and stress fractures, some of which result in catastrophic failure. However, there is still a need to understand at a detailed microstructural level how this damage progresses in the context of the wider joint tissue complex, i.e. the articular surface, the hyaline and calcified cartilage, and the subchondral bone. MC3 bones from non-fractured joints were obtained from the right forelimbs of 16 Thor...
Rhodin M, Johnston C, Holm KR, Wennerstrand J, Drevemo S.A common opinion among riders and in the literature is that the positioning of the head and neck influences the back of the horse, but this has not yet been measured objectively. Objective: To evaluate the effect of head and neck position on the kinematics of the back in riding horses. Methods: Eight Warmblood riding horses in regular work were studied on a treadmill at walk and trot with the head and neck in 3 different predetermined positions achieved by side reins attached to the bit and to an anticast roller. The 3-dimensional movement of the thoracolumbar spine was measured from the posit...
Holmström M, Fredricson I, Drevemo S.The trotting gait of 4 approved Swedish Warmblood stallions with a mean gait score > or = 8.67 (maximum score = 10) at official performance tests was recorded by high speed film (approximately 250 frames/sec). Angular patterns and hoof trajectories of the left fore and hind limbs were analysed, and presented as mean and standard deviation curves. The horses had a mean stride duration of 794.0 msec (sd 13.7) and the mean diagonal advanced placement was +29.8 msec (sd 7.6). The variation in angular patterns between the horses was greatest during the swing phase. The trajectory of the hind hoof r...
Reed SK, Kramer J, Thombs L, Pitts JB, Wilson DA, Keegan KG.To compare results for initial body-mounted inertial sensor (BMIS) measurement of lameness in equids trotting in a straight line with definitive findings after full lameness evaluation. Methods: 1,224 equids. Methods: Lameness measured with BMIS equipment while trotting in a straight line was classified into categories of none, forelimb only, hind limb only, and 8 patterns of combined forelimb and hind limb lameness (CFHL). Definitive findings after full lameness evaluation were established in most horses and classified into types (no lameness, forelimb- or hind limb-only lameness, CFHL, or la...
Shurtleff TL, Engsberg JR.Hippotherapy (HPOT) is a therapy that uses horse movement. This pilot investigation objectively evaluated the efficacy of HPOT in improving head/trunk stability in children with cerebral palsy (CP). The participants were six children with spastic diplegia and six children without disability. Head and trunk stability was challenged by using a motorized barrel and measured by a video motion capture system before and after a 12-week intervention of 45 min of HPOT a week. The variables measured were anterior-posterior (AP) translation of the head, and spine at five points and average AP head angle...
Brown NA, Kawcak CE, McIlwraith CW, Pandy MG.Articular injuries in athletic horses are associated with large forces from ground impact and from muscular contraction. To accurately and noninvasively predict muscle and joint contact forces, a detailed model of musculoskeletal geometry and muscle architecture is required. Moreover, muscle architectural data can increase our understanding of the relationship between muscle structure and function in the equine distal forelimb. Muscle architectural data were collected from seven limbs obtained from five thoroughbred and thoroughbred-cross horses. Muscle belly rest length, tendon rest length, m...
Dyson S, Murray R.Neurectomy of the deep branch of the lateral plantar nerve and plantar fasciotomy have become accepted as methods of treatment of proximal suspensory desmopathy (PSD), but there are limited long-term studies documenting the outcome. Objective: To describe long-term follow-up in horses with PSD alone or with other injuries contributing to lameness and poor performance, including complications, following neurectomy and fasciotomy. Methods: Follow-up information was acquired for 155 horses that had undergone neurectomy and fasciotomy for treatment of PSD between 2003 and 2008. Success was classif...
Robert C, Valette JP, Denoix JM.The purpose of this study was to evaluate the effects of speed and slope on the activity of trunk muscles. The electromyographic (EMG) activity of the splenius (Sp), longissimus dorsi (LD) and rectus abdominis (RA) muscles was recorded with surface electrodes during treadmill locomotion at trot for different combinations of speed (3.5 to 6 m/s) and slope (0 to 6%). Raw EMG signals were processed to determine activity duration, onset and end and integrated EMG (IEMG). For the 3 muscles investigated, onset and end of activity were obtained earlier in the stride cycle when speed increased. A long...
Corbin LJ, Blott SC, Swinburne JE, Sibbons C, Fox-Clipsham LY, Helwegen M, Parkin TD, Newton JR, Bramlage LR, McIlwraith CW, Bishop SC, Woolliams JA....Osteochondrosis is a developmental orthopaedic disease that occurs in horses, other livestock species, companion animal species, and humans. The principal aim of this study was to identify quantitative trait loci (QTL) associated with osteochondritis dissecans (OCD) in the Thoroughbred using a genome-wide association study. A secondary objective was to test the effect of previously identified QTL in the current population. Over 300 horses, classified as cases or controls according to clinical findings, were genotyped for the Illumina Equine SNP50 BeadChip. An animal model was first implemented...
Docking SI, Daffy J, van Schie HT, Cook JL.Investigations into the response of the superficial digital flexor tendon (SDFT) of the Thoroughbred horse to mechanical stimuli have been limited to in vitro cell culture studies focused primarily on gene expression of critical matrix proteins. It is uncertain how well in vitro outcomes translate to the tendon of the horse during exercise. The current study examined changes in tendon structure in response to maximal exercise using ultrasound tissue characterisation (UTC) to scan the SDFT prior to and after competitive racing. UTC uses contiguous transverse ultrasound images to assess the dyna...
Hurtig MB, Fretz PB, Doige CE, Schnurr DL.The mechanisms and completeness of equine articular cartilage repair were studied in ten horses over a nine month period. Large (15 mm square) and small (5 mm square) full-thickness lesions were made in weight bearing and nonweight bearing areas of the radiocarpal, middle carpal and femoropatellar joints. The horses were euthanized in groups of two 1, 2.5, 4, 5 and 9 months later. Gross pathology, microradiography, and histopathology were used to evaluate qualitative aspects of articular repair. Computer assisted microdensitometry of safranin-O stained cartilage sections was used to quantitate...
Biknevicius AR, Mullineaux DR, Clayton HM.Gaited horses employ 4-beat stepping (singlefoot) gaits that extend into speeds typical of trots. Ground reaction force (GRF) patterns of these specialised gaits have not been reported; therefore, appraisal of these gaits using nongaited horse kinetics may lead to clinical misjudgements. Objective: GRFs of tölting Icelandic horses will be comparable in profile and magnitude with those of trotting horses. Methods: Forelimb and hindlimb GRFs were obtained for 10 Icelandic horses ridden at a tölt. These data were evaluated across 3 speed ranges: <2, 2.5-5 and >5 m/sec. Results: Virtually all ve...
Hill AE, Gardner IA, Carpenter TE, Stover SM.To assess concurrently the effects of moderate ligamentous suspensory apparatus injury (MLSAI), racing-speed exercise, and horseshoe characteristics on risk of catastrophic suspensory apparatus failure (SAF) or metacarpal condylar fracture (CDY) in forelimbs of racehorses. Methods: Cadavers of 301 Thoroughbred racehorses (108 with SAF, 33 with CDY and 160 control horses). Methods: A cross-sectional epidemiologic study was used to describe distributions and relationships between MLSAI, exercise, and horseshoe variables. Logistic regression was used to assess potential risk factors for developin...
Hardeman AM, Byström A, Roepstorff L, Swagemakers JH, van Weeren PR, Serra Bragança FM.Clinical assessment of spinal motion in horses is part of many routine clinical exams but remains highly subjective. A prerequisite for the quantification of spinal motion is the assessment of the expected normal range of motion and variability of back kinematics. The aim of this study was to objectively quantify spinal kinematics and between -measurement, -surface and -day variation in owner-sound horses. In an observational study, twelve owner-sound horses were trotted 12 times on four different paths (hard/soft straight line, soft lunge left and right). Measurements were divided over three ...
Radtke CL, Danova NA, Scollay MC, Santschi EM, Markel MD, Da Costa Gómez T, Muir P.To determine changes in the distal ends of the third metacarpal and metatarsal bones (MCIII and MTIII) of Thoroughbred racehorses that had sustained a catastrophic condylar fracture during high-speed exercise. Methods: Fractured and contralateral MCIIIs and MTIIIs from 11 Thoroughbred racehorses that sustained a displaced condylar fracture during racing, both MCIIIs from 5 Thoroughbred racehorses euthanatized because of a catastrophic injury other than a condylar fracture, and both MCIIIs from 5 horses of other breeds that had not been professionally trained or raced. Methods: Macroscopic obse...
Rooney MF, Porter RK, Katz LM, Hill EW.Variation in the myostatin (MSTN) gene has been reported to be associated with race distance, body composition and skeletal muscle fibre composition in the horse. The aim of the present study was to test the hypothesis that MSTN variation influences mitochondrial phenotypes in equine skeletal muscle. Mitochondrial abundance and skeletal muscle fibre types were measured in whole muscle biopsies from the gluteus medius of n = 82 untrained (21 ± 3 months) Thoroughbred horses. Skeletal muscle fibre type proportions were significantly (p < 0.01) different among the three MSTN genotypes and mito...
Patterson-Kane JC, Wilson AM, Firth EC, Parry DA, Goodship AE.This study was undertaken to test the hypothesis that collagen fibrils, the submicroscopic units of strength in tendon, would hypertrophy in response to a specific defined training programme. Fibril diameters were measured in central and peripheral regions of superficial digital flexor tendon (SDFT) samples from five 18-month-old horses which underwent a subsequent 18 month training programme and 6 age- and sex-matched controls. Central region fibrils from the trained horses had a mass-average diameter (MAD) of 105.3 nm, which was significantly lower (P < 0.01) than that of 131.7 nm for the...
Ursini TL, Amelse LL, Elkhenany HA, Odoi A, Carter-Arnold JL, Adair HS, Dhar MS.Bone marrow-derived mesenchymal stem cells (BM-MSCs) are frequently used in the treatment of musculoskeletal injuries. Fully characterised cells that are readily available for use is optimum. Allogenic BM-MSCs can satisfy the need for rapid treatment, however, their safety has been questioned. Objective: Objectives were to characterise BM-MSCs from an adult donor horse, in vitro, and to identify and describe adverse reactions that occurred following their injection into other horses. We hypothesised that BM-MSCs capable of proliferation, differentiation and lacking MHC II from one donor could ...
Eliashar E, McGuigan MP, Wilson AM.Collapsed heels conformation has been implicated as causing radical biomechanical alterations, predisposing horses to navicular disease. However, the correlation between hoof conformation and the forces exerted on the navicular bone has not been documented. Objective: The angle of the distal phalanx in relation to the ground is correlated to the degree of heel collapse and foot conformation is correlated to the compressive force exerted by the deep digital flexor tendon on the navicular bone. Methods: Thirty-one shod Irish Draught-cross type horses in routine work and farriery care were trotte...
Priest HL, Irby NL, Schlafer DH, Divers TJ, Wagner B, Glaser AL, Chang YF, Smith MC.Borrelia burgdorferi, the etiologic agent of Lyme disease is a tick born spirochetal infection. Clinical signs of Lyme borreliosis are uncommon in horses, but when present they are often vague and nonspecific. In horses, Lyme borreliosis has been implicated in musculoskeletal, neurological, reproductive, and ocular disorders, including uveitis, but definitive diagnosis can be challenging as the causative agent is rarely isolated and serologic tests can be unreliable and do not confirm active disease. Here, we report two cases of equine uveitis associated with B. burgdorferi based on the identi...
Walmsley JP, Pettersson H, Winberg F, McEvoy F.The surgical treatment of impingement of dorsal spinous processes (DSPs) at 2 equine veterinary hospitals following a similar diagnostic and surgical protocol is described with special reference to the diagnosis and case selection. The diagnosis was made from clinical examination and results of radiography and diagnostic analgesia of the affected sites. Scintigraphy was also used as an aid to diagnosis at one hospital. Surgical treatment was generally recommended when conservative treatment, which included 3-9 months rest, intralesional corticosteroids and physiotherapy, had failed. The DSPs w...
Goodman SA, May SA, Heinegård D, Smith RK.The effect of strain and transforming growth factor beta on equine tendon fibroblasts (tenocytes) was assessed in vitro. Tenocytes were isolated from flexor and extensor tendons of horses from foetal to 10 years of age. These cells were cultured until confluent on collagen-coated silicone dishes. Cyclic biaxial strain of 9+/-1% was applied at 0.5 Hz for 24 hours with or without added TGFbeta1 or 3 (10 ng/ml). Proliferation and synthetic responses were dependent on the tendon of origin. Neither strain nor TGFbeta caused flexor tenocytes to proliferate significantly, while strain alone did proli...
Zsoldos RR, Kotschwar A, Kotschwar AB, Rodriguez CP, Peham C, Licka T.The rectus abdominis (RA) and oblique external abdominal (OEA) muscles are both part of the construction of the equine trunk and thought to be essential for the function of the spine during locomotion. Although RA activity at trot has previously been investigated, the relationship between OEA and RA at walk and trot has not yet been described. Objective: To document abdominal muscle activities during walk and trot, and test the hypothesis that muscle activity at walk would be smaller than at trot. Methods: Six horses (8-20 years old, 450-700 kg) were used for surface electromyography (EMG) mea...
Watson JC, Wilson AM.Three muscles from the proximal equine forelimb were dissected in order to investigate their potential to contribute to proximal limb mechanics. Muscle mass, fibre length, tendon mass and tendon length were measured from biceps brachii, triceps brachii, supraspinatus and lacertus fibrosus (biceps lateral head mass 171-343.4 g and fibre length 0.5-0.8 cm; biceps medial head mass 283-500 g and fibre length 2.2-4 cm; biceps tendon mass 121.8-260 g and tendon length 35-44 cm; triceps long head mass 3200-6663 g and fibre length 19-26.3 cm; triceps lateral head mass 513.8-1240 g and fibre length 17....
Robert C, Valette JP, Degueurce C, Denoix JM.The purpose of this study was to demonstrate the feasibility of surface electromyography in the horse and to correlate electromyographic activity with kinematic data. Surface electromyography of seven hindlimb muscles was recorded in five horses at trot on a treadmill. Simultaneously, kinematic analysis of the hindlimb was performed using a three-dimensional system and a unidirectional accelerometer was attached to the hoof. Electromyographic activities of the gluteus medius, vastus lateralis and two parts of the biceps femoris started in the late part of the swing phase and ended in the late ...
Brama PA, Karssenberg D, Barneveld A, van Weeren PR.The objective of this study was to map topographically contact areas and pressure distributions on the proximal articular surface (PAS) of the proximal phalanx (PI) under various clinically relevant loading conditions. Left and right forelimbs of 13 mature horses were transected halfway down the radius and loaded in a position mimicking the weightbearing attitude close to the midstance phase. Five loads were used which corresponded with loads that can be expected in different gaits or during athletic performance (stance: 1800 N, walk: 3600 N, trot: 5400 N, gallop: 10,500 N and jumping: 12,000 ...
Estberg L, Stover SM, Gardner IA, Drake CM, Johnson B, Ardans A.To investigate the relation between several racing speed history characteristics and risk of fatal skeletal injury (FSI) in racing Thoroughbreds. Methods: 64 Thoroughbreds euthanatized during a 9-month period in 1991 at a California racemeet because of a catastrophic fracture incurred while racing (cases), identified retrospectively. For each race in which an FSI occurred, 1 control horse was randomly selected from the noncatastrophically injured participants. Methods: Racing and officially timed workout histories were obtained for each horse. Several history characteristics were calculated to...