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.
Weller R, Pfau T, Babbage D, Brittin E, May SA, Wilson AM.The importance of a reliable method for conformation studies is generally acknowledged, but there are only limited data on the accuracy and precision of current assessment methods. Objective: To assess (1) the accuracy and repeatability of marker placement, (2) influence of stance of the horse on conformational parameters, (3) practicality of a computerised motion analysis system and (4) to compare the computerised motion analysis system to photographic systems of assessment. Methods: Twenty-eight reflective markers placed over anatomical landmarks were located in 3D using a computerised motio...
Ryan CT, Schaer BL, Nunamaker DM.A device is needed to safely and wirelessly evaluate accelerations experienced by the horse hoof under a variety of surface conditions with the horse exercising at training or racing speeds. Objective: To develop a miniaturised wireless data acquisition system (WDAS) which reliably records hoof accelerations and the times over which they occur in a minimally invasive manner in the exercising Thoroughbred. Methods: The following criteria were set for device development: production of a lightweight and minimally invasive system, which provides an adequate acceleration range, appropriate frequenc...
Schaer BL, Ryan CT, Boston RC, Nunamaker DM.There is a need to determine accelerations acting on the equine hoof under field conditions in order to better assess the risks for orthopaedic health associated with shoeing practices and/or surface conditions. Objective: To measure the acceleration profiles generated in Thoroughbred racehorses exercising at high speeds over dirt racetracks and specifically to evaluate the effect of a toe grab shoe compared to a flat racing plate, using a newly developed wireless data acquisition system (WDAS). Methods: Four Thoroughbred racehorses in training and racing were used. Based on previous trials, e...
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...
Santschi EM, Leibsle SR, Morehead JP, Prichard MA, Clayton MK, Keuler NS.There is little information available about conformational changes in the forelimbs of growing foals. Objective: To describe the conformation of the carpus and fetlock of Thoroughbred foals from birth to yearling sale age. Methods: Subjective assessments of the fetlock and carpal conformation of 119 Thoroughbred foals were made within the first month of life and then at 30 day intervals until at least age 120 days. At least 70 subjects were examined further at 60 day intervals until September of their second year. Conformation grades are reported for 5 age groups: first 7 days and at a mean of...
Kroekenstoel AM, van Heel MC, van Weeren PR, Back W.Distal limb conformation is generally accepted to be an important item with respect to performance and soundness in mature horses, but little is known about the developmental aspects. Objective: To gain insight into the development of distal limb conformation and to assess the possible consequences of uneven feet in foals. Methods: Conformation of the distal front limbs of 23 Warmblood foals was scored visually and measured using radiographs, at ages 27 and 55 weeks. At the same ages, pressure measurements were made under both front feet. Results: At both ages the hoof-pastern axis was broken-...
Gnagey L, Clayton HM, Lanovaz JL.The tarsal joint is a frequent site of lameness, but little objective information is available regarding the effects of tarsal conformation on joint movements or forces. Objective: To compare tarsal kinematics and kinetics in horses with large, intermediate and small tarsal angles. Methods: Sagittal plane standing angle of the right tarsal joint was measured in 16 horses as they stood squarely with the hind hooves vertically beneath the hip joint. Tarsal angles were classified as small (< 155.5 degrees), intermediate (155.5-165.5 degrees) or large (> 165.5 degrees). Reflective markers, attache...
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....
van Heel MC, Kroekenstoel AM, van Dierendonck MC, van Weeren PR, Back W.Conformational traits are important in breeding, since they may be indicative for performance ability and susceptibility to injuries. Objective: To study whether certain desired conformational traits of foals are related to lateralised behaviour while foraging and to the development of uneven feet. Methods: Twenty-four Warmblood foals, born and raised at the same location, were studied for a year. Foraging behaviour was observed by means of weekly 10 min scan-sampling for 8 h. A preference test (PT) was developed to serve as a standardised tool to determine laterality. The foals were evaluated...
Vandeweerd JM, Desbrosse F, Clegg P, Hougardy V, Brock L, Welch A, Cripps P.The distal limb innervation of the horse has been studied extensively to allow use of local anaesthetic techniques to detect the origin of pain in lameness. However, the innervation of the lumbar spine has so far been poorly described and a more precise description may assist clinicians to localise back pain in the horse. Objective: To gain better knowledge of the innervation of the lumbar spine and identify salient anatomical features that might be used for diagnostic and therapeutic ultrasound guided injections. Methods: The spines of 8 mature horses were dissected. Branches of the dorsal ra...
Burn JF.Little is known about the interaction of the hoof with the ground at the onset of stance phase although is it widely believed that high power collisions are involved in the aetiopathology of several conditions causing lameness. Objective: To answer 3 questions regarding the fundamental nature of hoof-ground collision: (1) is the collision process deterministic for ground surfaces that present a consistent mechanical interface (2) do collision forces act on the hoof in a small or large range of directions and (3) Is the hoof decelerated to near-zero velocity by the initial deceleration peak fol...
Weller R, Pfau T, May SA, Wilson AM.Assessment of conformation is commonly used in the selection of horses for performance purposes. Little information is available on the normal range of conformational traits within the Thoroughbred population. Objective: To describe variations in conformation in a cohort of racing Thoroughbreds in order to provide a set of baseline standards within which conformational traits can be considered normal. Methods: Ninety-eight conformational parameters were measured in a cohort of 108 National Hunt racehorses using a digital motion analysis system. The measurements consisted of segment lengths, jo...
Singer ER, Barnes J, Saxby F, Murray JK.Two related studies on injuries sustained by event horses during competition and during training are reported. During the cross-country phase of competition, the most common injuries were lacerations and abrasions to the carpus and stifle. Superficial digital flexor tendonitis and exertional rhabdomyolysis were significantly more common during Cours Complete Internationale (CCI) competitions compared to one-day event (ODE) competitions. The difference in injury types at ODEs and CCI competitions probably relates to the increased athletic demands of the CCI and the closer veterinary observation...
Stock KF, Distl O.Results of mare performance tests in the field (MPT-F) of 10,949 mares, mare performance tests at station (MPT-S) of 1,712 mares, and inspections of horses intended for sale at riding horse auctions (AU) of 4,772 horses were used to investigate genetic correlations between corresponding performance traits. Mare performance tests were held in 1995 to 2004 and auction inspections in 1999 to 2004. Scores on a scale from 0 to 10 were given for gaits under rider (walk, trot, canter), rideability (evaluated by judging commission and test rider), free-jumping (ability, style, total), and character. R...
Simon EL, Gaughan EM, Epp T, Spire M.To determine the amount of time required for surface temperatures of thoracic and pelvic limbs in horses to return to pre-exercise temperatures after high-speed treadmill exercise, as detected via infrared thermographic imaging. Methods: Prospective study. Methods: 6 Thoroughbreds. Methods: All horses had been trained on and conditioned to use of a high-speed treadmill. Baseline thermographic images were obtained 3 days prior to exercise (baseline). Horses were exercised on a treadmill at a walk for 5 minutes, a slow trot (3 m/s) for 5 minutes, a trot (5 to 6 m/s) for 5 minutes, and a slow gal...
Abraham G, Kottke C, Ammer H, Dhein S, Ungemach FR.Muscarinic receptors are considered to be of comparable clinical importance in chronic obstructive pulmonary disease (COPD) in equines and in humans. At present, data are scarce on the expression and distribution of probable subtypes of these receptors and their signalling pathways in airway segments, including lung parenchyma and bronchial and tracheal epithelium with the underlying smooth muscle in horses. Specific [N-methyl-3H]scopolamine chloride ([3H]NMS) binding to all three tissues was saturable and of high affinity, with KD values ranging between 1.6+/-0.7 and 1.9+/-0.3 nmol/L. [3H]NMS...
Manso Filho HC, McKeever KH, Gordon ME, Costa HE, Watford M.One of the hallmarks of insulin resistance is a reduction in glucose transporter-4 (Glut-4) expression in adipose tissue but not in skeletal muscle. However, while Glut-4 has been demonstrated in skeletal and cardiac muscles in horses it has not been demonstrated in adipose tissue. The initial objectives of the present study were: (1) to test the hypothesis that Glut-4 expression would vary between selected key skeletal muscles; (2) to test the hypothesis that it would also vary between representative adipose tissue depots, and (3) to see whether expression would be greater in adipose tissue c...
Zarucco L, Wisner ER, Swanstrom MD, Stover SM.Biomechanical models that compute the lengths and forces of muscle-tendon units are broadly applicable to the study of factors that promote injury and the planning and effects of orthopedic surgical procedures in equine athletes. A three-dimensional (3D) generic musculoskeletal model of the equine forelimb comprised of bony segment, muscle-tendon, and ligament information, was developed based on high-resolution computed tomographic (CT) and T1-weighted magnetic resonance (MR) images from an isolated forelimb of a Thoroughbred racehorse. Image fusion was achieved through coregistration of CT an...
Toppin DS, Lori DN.A 16-year-old 500-kg (1,100-lb) Quarter Horse stallion was examined because of acute severe lameness involving the left hind limb. Results: Examination revealed signs of failure (concurrent flexion of the tarsus and extension of the stifle [femorotibial] joint) of the caudal component of the reciprocal apparatus. Results of radiographic evaluation ruled out fracture or joint injury as causes of the lameness. During the next 48 hours, the reciprocal apparatus on the left hind limb progressively deteriorated until the horse became non-weight bearing on the limb. Results: The horse wore a full-li...
Yates AC, Stewart AA, Byron CR, Pondenis HC, Kaufmann KM, Constable PD.To determine the effects of sodium hyaluronate (HA) in combination with methylprednisolone acetate (MPA) on interleukin-1 (IL-1)-induced inflammation in equine articular cartilage pellets. Methods: Chondrocytes collected from 7 horses euthanatized for problems unrelated to the musculoskeletal system. Methods: Chondrocyte pellets were treated with medium (negative control); medium containing IL-1 (positive control); or medium containing IL-1 with MPA only (0.05 or 0.5 mg/mL), HA only (0.2 or 2 mg/mL), or MPA (0.05 or 0.5 mg/mL) and HA (0.2 or 2 mg/mL) in combination. Proteoglycan (PG) synthesis...
Kelmer G, Kramer J.Shortening of the deep digital flexor tendon was performed by tenotomy, overlapping and anastomosis. The procedure was performed on a two-year-old Quarter Horse Mare with distal interphalangeal joint hyperextension with subluxation and metatarsophalangeal joint hyperextension. These problems originated from damage to the digital flexor tendons, presumably due to previous distal limb trauma. The procedure markedly improved the mare's level of comfort, degree of ambulation and limb conformation. Two years following surgery the mare was comfortable at pasture.
Norrdin RW, Stover SM.Mechanical overload leads to a common arthrosis in the metacarpal condyle of the fetlock joint of racehorses. This is usually asymptomatic but severe forms can cause lameness. Subchondral bone failure is often present and the predictability of the site provided an opportunity to study of the progression of bone failure from microcracks to actual collapse of subchondral bone. Twenty-five fetlock condyles from racehorses with various stages of disease were selected. Stages ranged from mild through severe subchondral bone sclerosis, to the collapse of bone and indentation or loss of cartilage kno...
Franci P, Leece EA, Brearley JC.Patient positioning and long anaesthetic duration required for magnetic resonance imaging (MRI) may result in a higher frequency of post anaesthetic myopathy/neuropathy syndrome (PAMNS) as compared to horses undergoing anaesthesia for surgery. Objective: Equine anaesthesia for MRI is associated with a higher frequency of PAMNS than anaesthesia for nonemergency, nonabdominal surgery. Methods: Anaesthetic and medical records of horses (n = 633) undergoing MRI or surgery between January 2001 and January 2005 (inclusive), were reviewed. Information obtained included patient details (breed, sex, ag...
Varcoe-Cocks K, Sagar KN, Jeffcott LB, McGowan CM.Despite the prevalence of orthopaedic injuries to horses, there is no objective means of quantifying the intensity of musculoskeletal pain. Objective: Mechanical nociceptive thresholds (MNT) can be measured repeatably by pressure algometry in horses and MNTs are correlated with both severity of clinical signs and subjective scores of muscle pain on palpation in horses with suspected sacroiliac dysfunction (SID). Methods: The technique of pressure algometry and its repeatability was tested at 4 anatomical sites on either side of the thoracolumbar and pelvic region in 12 Thoroughbreds in trainin...
Knox PM, Watkins JP.A method for proximal interphalangeal joint (PIP joint) arthrodesis that provides a stable fixation and minimal duration of cast support is evaluated retrospectively. Objective: Evaluate the clinical use of a combined plate-screw method for PIP joint arthrodesis in a large number of horses. Methods: The records of 53 horses undergoing PIP joint arthrodesis were reviewed. Arthrodesis was performed with a dorsally placed 3-, 4- or 5-hole narrow dynamic compression plate (DCP) with 2 transarticular cortex screws placed in lag fashion either side of the plate. Subject details, clinical presentatio...
Muylle S, Vanderperren K, Saunders J, Simoens P.Desmopathy of the accessory ligament of the deep digital flexor tendon (ALDDFT) in the hindlimb has recently been described as a cause of lameness in horses. However, there is limited morphometric data on this ligament. In the present study, the ALDDFT was carefully dissected in 165 hindlimbs that were collected from an abattoir. Length, width (lateral-to-medial) and thickness (plantar-to-dorsal) of the ligament were measured. It was found that the ALDDFT may be absent in a minority of horses, but when it was present the general morphology was variable. The ALDDFT can be a single rectilinear s...
Middleton SB, Foley SJ, Foy MA.National Hunt jockeys suffer a disproportionate number of clavicular fractures and their return to riding may be considerably delayed by refracture and symptomatic nonunion, with obvious implications. We report six such cases in which excision of the clavicular fragment distal to the fracture was associated with an early return to work and no recurrent injury to the shoulder.
Senos R, Ribeiro MS, Martins Kde S, Pereira LV, Mattos MF, Kfoury Júnior JR, Rodrigues MR.Although bodypainting has been reported as a great resource for teaching surface anatomy of humans, its use in veterinary anatomy has not been scientifically reported. In the present study, bodypainting was performed on 4 horses for anatomy teaching purposes of the equine locomotor apparatus. We aimed to use the bodypainting method as an additional tool to classic teaching and to test the relevance of our purpose. Twenty one Brazilian veterinary students were given a 90-min session, which included a presentation of painted horses, with opportunities for the students to ask questions and to pal...
Serteyn D, Lavergne L, Coppens P, Mottart E, Philippart C, Micheels M, Lamy M.Measurements of muscular microcirculation in horses anaesthetised with halothane were performed by laser Doppler flowmetry. Variations of microcirculation in the compressed and uncompressed triceps brachii were measured when horses were positioned in dorsal recumbency after a prolonged period in lateral recumbency. A significant post ischaemic hyperaemia was recorded in horses which developed a post anaesthetic myositis.
Norman WM, Court MH, Dodman NH, Pipers FS.Muscle surface capillary blood flow was measured in the biceps femoris and lateral head of the triceps brachii muscles in six horses before and during halothane anesthesia by using laser Doppler flowmetry. During 90 minutes of anesthesia, muscle surface capillary blood flow was reduced to 20% to 40% of preanesthetic values. Muscle surface capillary blood flow tended to be lower in dependent muscles than in nondependent muscles, and this disparity was greater in the forelimbs than in the hind limbs.
Auer JA, Watkins JP, White NA, Taylor TS, Rooney JR.Fractures of the fourth carpal bone were diagnosed in 5 horses; 3 fractures were associated with fracture of the intermediate carpal bone. The diagnosis was delayed in all 5 horses, apparently because of the moderate nature of the clinical signs. Open surgical reduction with lag screw type fixation was used in all horses. Because of delayed treatment, transfixation of carpal bones (necessary for stability), and surgical trauma, degenerative joint disease with osteophyte formation occurred in all 5 horses. None of the 5 horses was able to begin or return successfully to work, although 4 of the ...
Jenner F, van Osch GJ, Weninger W, Geyer S, Stout T, van Weeren R, Brama P.Articular cartilage regeneration is the focus and goal of considerable research effort. Since articular chondrocytes descend from a distinct cohort of progenitor cells located in embryonic nascent joints (interzones), establishing the timing of equine interzone formation is an essential first step towards understanding equine joint and articular cartilage development. Objective: To establish the time frame during which the equine femorotibial interzone forms. Methods: Descriptive anatomical study. Methods: Equine embryos were harvested at 37 (E37), 40, 42, 45, 50 and 65 days' gestation. The fe...
Murray RC, Dyson SJ, Weekes JS, Branch MV, Hladick S.Bone-phase scintigraphy is sensitive to the dynamic process of bone modeling and remodeling, which may be adaptive or pathologic. Our knowledge of normal patterns of radiopharmaceutical uptake (RU) is limited, making interpretation of images problematic. It is therefore important to characterize normal patterns of RU at specific sites and relate these to age and exercise, to ensure valid interpretation of images in clinical cases with subtle lesions. This study aimed to characterize patterns of uptake of radiopharmaceutical in the distal tarsal region in clinically normal horses, and to invest...
Goodwin M, Klufts M, Workman J, Thambyah A, Vanholsbeeck F.To explore the ability of polarisation-sensitive optical coherence tomography (PS-OCT) to rapidly identify subtle signs of tissue degeneration in the equine joint. Polarisation-sensitive optical coherence tomography (PS-OCT) images were systematically acquired in four locations along the medial and lateral condyles of the third metacarpal bone in five dissected equine specimens. Intensity and retardation PS-OCT images, and anomalies observed therein, were then compared and validated with high resolution images of the tissue sections obtained using Differential Interference contrast (DIC) optic...
Simonato SP, Bernardina GRD, Ferreira LCR, Silvatti AP, Barcelos KMC, da Fonseca BPA.This study aimed to provide a preliminary description of the sagittal and transverse plane kinematics of the thoracolumbar spine of Mangalarga Marchador (MM) horses performing the marcha batida gait, led in-hand. We evaluated the pattern of angular movement and the mean amplitude of six specific angles. An optoelectronic system was used for 3D kinematic analysis (19 cameras, 250 Hz). They were positioned around the horses and an acquisition volume of 16 × 4.8 × 3 meters was used. Eight retroreflective markers were fixed on the spine of the animals over thoracic vertebrae 8 (T8), 12 (T12), 15...
Trotter GW, McIlwraith CW.Surgical procedures completed under arthroscopic guidance have become commonplace in many equine practices and have largely replaced surgery using arthrotomy incisions. With a limited amount of equipment, numerous diagnostic and surgical procedures can be completed. Surgeons need to become familiar with regional and intraarticular (intrasynovial) anatomy to ensure that proper surgical approaches are used, access to the lesion will be realized, and potential complications will be minimized. Specialized motorized instruments and surgical lasers are now available and may be useful in the treatmen...
Pollock S, Stover SM, Hull ML, Galuppo LD.The first objective of this study was to experimentally determine surface bone strain magnitudes and directions at the donor site for bone grafts, the site predisposed to stress fracture, the medial and cranial aspects of the transverse cross section corresponding to the stress fracture site, and the middle of the diaphysis of the humerus of a simplified in vitro laboratory preparation. The second objective was to determine whether computing strains solely in the direction of the longitudinal axis of the humerus in the mathematical model was inherently limited by comparing the strains measured...
Clothier J, Small A, Hinch G, Barwick J, Brown WY.Chronic musculoskeletal pathologies are common in horses, however, identifying related effects can be challenging. This study tested the hypothesis that movement sensors and analgesics could be used in combination to confirm the presence of restrictive pathologies by assessing lying time. Four horses presenting a range of angular limb deformities (ALDs) and four nonaffected controls were used. The study comprised two trials at separate paddock locations. Trial A consisted of a 3-day baseline phase and 2 × 3-day treatment phases, during which two analgesics were administered to two ALD horses...
Perrone G, Lastra Y, González C, Caggiano N, Giménez R, Pareja R, De Simone E.Osteoarthritis (OA) is the most prevalent arthropathy in sport horses. The administration of a platelet lysate (PL) is an alternative method for the treatment of musculoskeletal conditions. The mechanisms by which PL exerts its beneficial effects have not been determined, and less is known about its effect on the activity of the proteolytic enzymes of the synovial fluid of equines with OA. In this work, the effect of the administration of PL to horses with OA was analyzed both clinically and molecularly by determining the levels of matrix metalloproteinase-2 (MMP-2), matrix metalloproteinase-9...
Pérez-Nogués M, Derham A, Marmion J, True Baker W.Shallow lucencies less than 4 mm deep into the medial femoral condyle (MFC) are frequent in Thoroughbred horses undergoing screening sales radiographs. It is unclear if these shallow defects are precursors to larger cystic lesions or if they are fully developed defects that remodel into a flattened femoral condyle. Objective: To evaluate radiological lucencies of the MFC and their progression in size, in a cohort of Thoroughbred horses, ranging from 5 to 18 months of age and to report on the racing careers of these horses compared to their maternal siblings free of stifle pathology. Methods:...
Armentrout AR, Beard WL, White BJ, Lillich JD.The flexion test is routinely used in lameness and prepurchase examinations. There is no accepted standard for duration of flexion or evidence that interpretation of results would differ with different durations of flexion. Objective: There will be no difference in interpretation of proximal hindlimb flexion for 5 or 60 s. Methods: Video recordings of lameness examinations of 34 client-owned horses were performed that included: baseline lameness, proximal hindlimb flexion for 60 s, and flexion of the same limb for 5 s. Videos were edited to blind reviewers to the hypothesis being tested. The b...
Bardin AL, Tang L, Panizzi L, Rogers CW, Colborne GR.Musculoskeletal injuries in horses are the main cause of retirement, rest, and death. To understand these injuries, it is necessary to study loads in muscles, tendons and ligaments. A musculoskeletal model makes it possible to consider all structures simultaneously and avoids invasive measurements. At present, most computational models of the equine limb described in the literature have been limited to the distal limb. The aim of this study was to create a preliminary musculoskeletal model of the whole equine forelimb and to run it with kinematic data collected during gait. The model was devel...
Suwannachot P, Verkleij CB, Weijs WA, van Weeren PR, Everts ME.We investigated the effect of training on the Na+, K+-ATPase concentration in foal skeletal muscle by measurement of [3H]ouabain binding. From the 7th day after birth, 12 foals were divided in 3 groups: a) staying in a box stall (Box); b) staying in a box stall with a training regimen of an increasing number of sprints per day (Training); and c) staying on pasture (Pasture). Euthanasia was performed after 5 months. In semitendinosus muscle, the concentration of [3H]ouabain binding sites (pmol/g wet wt) was 181 +/- 6 in the Box, 220 +/- 15 in the Training, and 197 +/- 8 in the Pasture group (al...
Pease A.The use of molecular imaging of cartilage is the next vital step in understanding, treating, and training the equine athlete. Because of the logistics of precontrast and postcontrast medium imaging, the clinical usefulness of the examination has come into question. With the large number of horses undergoing high-field magnetic resonance imaging, the use of contrast medium administration and T1 mapping or T2 imaging precontrast and postcontrast medium administration may add a limited amount of time to the scan and has the potential to provide more detailed information about the chemical composi...
Douglas JE, Biddick TL, Thomason JJ, Jofriet JC.The equine laminar junction plays a vital role in transferring the forces of weight-bearing between the epidermal hoof wall and the bone of the third phalanx, but the way in which it performs this function is poorly understood. Using samples from sites varying proximodistally and circumferentially around the hoof, the stress/strain behaviour of this tissue was characterised in three directions: radial tension and proximodistal and mediolateral shear. The influences of toe angle and length were also examined. For all three test directions, the modulus of elasticity increased with increasing str...
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...
Dahlgren LA, Nixon AJ.To define a portion of the nucleotide sequences of each of the 6 insulin-like growth factor (IGF) binding proteins (IGFBPs) in horses and describe patterns of messenger RNA (mRNA) and protein expression for IGFBPs in normal equine tendons. Methods: 7 horses. Methods: Total RNA was extracted from the tensile region of normal superficial digital flexor tendons and reverse transcribed into complimentary DNA (cDNA). The cDNA was amplified via PCR, and products representing portions of each IGFBP were cloned and sequenced. Nucleotide sequences were used to deduce the amino acid sequences, and both ...
Kicker CJ, Peham C, Girtler D, Licka T.Support boots are thought to reduce tension on the superficial digital flexor tendon (SDTF) of the horse and are frequently recommended for horses convalescing after tendonitis, but evidence of their effectiveness is conflicting. Objective: To document the effects of 4 different types of support boots on fetlock joint angle in comparison to the unprotected fetlock. Methods: In 26 horses, the kinematics of the forelimb fetlock joint angle was measured at walk and trot on a treadmill when wearing 3 different types of support boots and 1 protective boot, as well as without boots. As outcome param...
Hellings IR, Dolvik NI, Ekman S, Olstad K.Some epiphyseal growth cartilage canals are surrounded by a ring of hypereosinophilic matrix consisting of collagen type I. Absence of the collagen type I ring may predispose canal vessels to failure and osteochondrosis, which can lead to fragments in joints (osteochondrosis dissecans). It is not known whether the ring develops in response to programming or biomechanical force. The distribution that may reveal the function of the ring has only been described in the distal femur of a limited number of foals. It is also not known which cells are responsible for producing the collagen ring. The a...
Diab S, Pascoe J, Shahriar M, Read D, Kinde H, Moore J, Odani J, Uzal F.There is increasing anecdotal evidence among horse owners, trainers and equine clinicians of a high prevalence of subepiglottic ulcers, suggested to have a negative effect on racing performance. Objective: To provide a prevalence study and pathological characterisation of laryngopharyngeal lesions with emphasis in the subepiglottic area and, in particular, subepiglottic ulcers. Methods: The study was carried out on 91 Thoroughbred racehorses received for post mortem examination from 4 major Southern California racetracks. The most common reason for submission was catastrophic musculoskeletal i...
Peat FJ, Kawcak CE.The current understanding of pathology as it relates to common diseases of the equine musculoskeletal system is reviewed. Conditions are organized under the fundamental categories of developmental, exercise-induced, infectious, and miscellaneous pathology. The overview of developmental pathology incorporates the new classification system of juvenile osteochondral conditions. Discussion of exercise-induced pathology emphasizes increased understanding of the contribution of cumulative microdamage caused by repetitive cyclic loading. Miscellaneous musculoskeletal pathology focuses on laminitis, w...
Walter LJ, Davies HM.Accuracy and limitations of a radiographic technique were established for measurement of metacarpal bone shape in horses. A radiographic index (RI) has been used to measure changes in third metacarpal (Mc3) bone shape in response to training in young racehorses. The aim of these experiments was to determine the effects of positioning of the radiographic equipment on RI measurements from lateromedial radiographs of a left ex vivo metacarpus. Repeatability of the RI measurement in left lateromedial and right mediolateral view Mc3s were evaluated. The width of the dorsal cortex (DC), palmar corte...
Janeczek M, Chrószcz A, Onar V, Henklewski R, Skalec A.Animal remains that are unearthed during archaeological excavations often provide useful information about socio-cultural context, including human habits, beliefs, and ancestral relationships. In this report, we present pathologically altered equine first and second phalanges from an 11th century specimen that was excavated at Wrocław Cathedral Island, Poland. The results of gross examination, radiography, and computed tomography, indicate osteoarthritis of the proximal interphalangeal joint, with partial ankylosis. Based on comparison with living modern horses undergoing lameness examination...
Hall MS, Vasey JR, Russell JW, Russell T.To evaluate the racing performance of horses that underwent ultrasound-guided intralesional injection of autologous bone marrow aspirate for treatment of selected forelimb suspensory ligament (body or branch) core lesions. Methods: Retrospective cohort study of 13 Standardbred and 17 Thoroughbred race horses. Methods: Autologous bone marrow aspirated from the sternebrae was injected, under ultrasound guidance, into suspensory ligament core lesions (body or branch). Racing records were reviewed for a comparison of performance before and after surgery. Results: Of the 13 Standardbreds, 9 (69%) h...
van Weeren PR, Knaap J, Firth EC.To elucidate the highly contentious role of copper in the pathogenesis of osteochondrosis. Objective: There would be no relationship between liver copper concentration of mares and foals and incidence of radiographically detectable osteochondrotic lesions in foals and yearlings was tested. Methods: Liver copper concentration was assessed in biopsies taken within 4 days after birth from both mares and foals and from the same foals at age 5 months. Biopsies were taken in the standing, sedated animal under ultrasonographic guidance. Radiographs were taken of both hocks (lateromedial, dorsoplantar...
