The skeletal system in horses comprises a complex structure of bones that provide support, protection, and mobility. Equine bones are involved in various physiological functions, including mineral storage and hematopoiesis. The bone structure in horses is categorized into different types, such as long bones, short bones, flat bones, and irregular bones, each serving specific roles in movement and stability. Research in this area explores topics such as bone development, remodeling, and the impact of nutrition and exercise on bone health. This page gathers peer-reviewed studies and academic articles that focus on the anatomy, physiology, and pathology of bones in horses, offering insights into conditions such as fractures, bone diseases, and the effects of aging on the equine skeletal system.
Lacourt M, Gao C, Li A, Girard C, Beauchamp G, Henderson JE, Laverty S.To correlate degenerative changes in cartilage and subchondral bone in the third carpal bone (C3) of Standardbred racehorses with naturally occurring repetitive trauma-induced osteoarthritis. Methods: Fifteen C3, collected from Standardbred horses postmortem, were assessed for cartilage lesions by visual inspection and divided into Control (CO), Early Osteoarthritis (EOA) and Advanced Osteoarthritis (AOA) groups. Two osteochondral cores were harvested from corresponding dorsal sites on each bone and scanned with a micro-computed tomography (CT) instrument. 2D images were assembled into 3D reco...
Southwood LL, Kawcak CE, Hidaka C, McIlwraith CW, Werpy N, Macleay J, Frisbie DD.To evaluate gene transfer in an equine metacarpal IV (MCIV) ostectomy model using adenoviral vectors encoding the human bone morphogenetic protein-2 and protein-7 gene (Ad-BMP-2/-7). Methods: Healthy adult horses (n = 15). Methods: A plate stabilized, critical size 1.5 cm ostectomy was created in left and right MCIV. The ostectomy site was injected with either Ad-green fluorescent protein (Ad-GFP) or Ad-hBMP-2/-7 at completion of surgery; the same treatment was assigned to both the left and right forelimb of each horse (n = 5 horses/group). Bone healing was evaluated radiographically every 2 w...
Tsuzuki N, Otsuka K, Seo J, Yamada K, Haneda S, Furuoka H, Tabata Y, Sasaki N.This study evaluated the therapeutic effects of a gelatin-β-TCP sponge (sponge) incorporating BMP-2 (BMP-2/sponge) on bone regeneration in equines. Six bone defects were created in third metacarpals of five thoroughbred horses, and a total of six treatments were applied in a randomized manner. The treatments were BMP-2/sponge, BMP-2/gelatin hydrogel sheet (sheet), free BMP-2, bFGF/sheet, plain sponge, and plain sheet. The defects were monitored for 16 weeks by radiography and then examined by histological analysis. Radiographic evaluation scores of bone regeneration revealed significantly gre...
Lawson JS, Bolt DM, May S, Smith AJ, Felstead CW, Weller R.Joint effusion is one of the classic radiographic signs of osteoarthritis, but no information is available regarding clinicians' ability to detect joint effusion radiographically. This study determined the accuracy and precision of experienced and inexperienced observers in detecting joint effusion of the distal interphalangeal (DIP), metacarpophalangeal (MCP) and midcarpal joints on radiographs. Fresh cadaverous forelimbs were loaded in a material testing machine to mimic a standing horse. The joints were gradually distended and lateromedial and dorsopalmar radiographs were acquired. The imag...
Tranquille CA, Parkin TD, Murray RC.Lateral condylar (LC) fractures of the third metacarpus (McIII) are a common reason for euthanasia in racehorses, and may be the result of repetitive overloading or cumulative pathological change. Magnetic resonance imaging (MRI) allows monitoring of bone and cartilage to detect pathological and adaptive changes that may be precursors of fracture. Objective: To describe bone and cartilage MRI features in the distal condyles of McIII of Thoroughbred racehorses, with and without condylar fracture. Objective: 1) A greater degree of bone and cartilage adaptation or pathology will be seen in fractu...
Wang D, Shi L, Griffith JF, Qin L, Yew DT, Riggs CM.Surface-based morphometry method is advantageous in its objectivity and increased capability in detecting focal morphological changes, but has not been applied in bone-related research. Orthopedics research in human has confirmed the association of the bone geometry in proximal femur and its fracture. In this study, surface-based morphometry is used to test the hypothesis that there is relationship between bone geometry and fracture risk of the proximal sesamoid bone (PSB) in forelimbs of Thoroughbred racehorses. The PSB surfaces were extracted from CT images of nonfractured forelegs (i.e., ri...
Adrian AM, Koene M, Roberts S, Doughty P, Bolas N, Kinns J, Brehm W, Gerlach K.The extent of fat suppression using short tau inversion recovery (STIR) imaging is variable between horses. Our aim was to determine if patient's age and/or hoof temperature have an influence on the T(1) relaxation time of bone marrow in the equine distal limb, thereby affecting the suppression of fat signal. Magnetic resonance imaging was conducted on standing horses and cadaver samples using a low-field magnet (0.27 T). The hoof temperature was measured at the lateral side of the coronary band. A modified inversion recovery fast spin-echo (IR-FSE) sequence was used to measure the signal inte...
Cesarini C, Macieira S, Girard C, Drolet R, d'Anjou MA, Jean D.The costochondral junction constitutes a potential site of infection in septic foals and it could be favored by thoracic trauma. Standard radiographs and ultrasonography are useful tools for diagnosis of this condition and ultrasound-guided needle aspiration could permit the definitive confirmation of infection. La jonction costochondrale constitue un site potentiel d’infection chez le poulain septicémique et le développement de l’infection pourrait être favorisée par un traumatisme costal. Les radiographies standards et l’échographie sont des aides diagnostiques et l’aspiration ...
Lorenz J, Brounts SH.This article reviews the pathology, diagnosis, and treatment of sacroiliac joint injuries. These injuries can be acute or chronic and can involve soft tissue structures surrounding the joint or the bony structures of the joint. The several diagnostic modalities for sacroiliac injuries vary in usefulness and accessibility. Treatment of sacroiliac problems is usually supportive and nonspecific and includes the use of antiinflammatory medications and an appropriate exercise regimen. The prognosis depends on the cause, but severe injuries can limit a horse's future athletic activity.
Deeg CA, Eberhardt C, Hofmaier F, Amann B, Hauck SM.Autoimmune uveitis is an intraocular inflammation that arises through autoreactive T-cells attacking the inner eye, eventually leading to blindness. However, the contributing molecular pathomechanisms within the affected tissues remain as yet elusive. The extracellular matrix (ECM) is a highly dynamic structure that varies tremendously and influences the encompassing tissue. In order to assess ECM re-modeling in autoimmune uveitis, we investigated the expression of ECM molecules fibronectin and osteopontin in vitreous and retina samples. This was carried out in the only spontaneous animal mode...
Lescun TB, Frank EA, Zacharias JR, Daggy JK, Moore GE.To compare the bone temperature and final hole dimensions associated with sequential overdrilling (SO) and single 6.2-mm drill bit (S6.2DB) methods used to create transcortical holes in the third metacarpal bones (MCIIIs) of horse cadavers. Methods: 60 MCIIIs from 30 horse cadavers. Methods: In phase 1, hole diameter, tap insertion torque, peak bone temperature, and postdrilling bit temperature for 6.2-mm-diameter holes drilled in the lateral or medial cortical region of 12 MCIIIs via each of three 2-bit SO methods with a single pilot hole (diameter, 3.2, 4.5, or 5.5 mm) and the S6.2DB method ...
Vanderperren K, Gielen I, Van Caelenberg A, Van der Vekens E, Raes EV, Hauspie S, van Bree H, Saunders JH.This article describes the ultrasonographic (US) appearance of bony abnormalities on the dorsal aspect of the third metacarpal/metatarsal bone of the equine fetlock in cadavers with radiographic signs of osteoarthrosis. After US, computed tomography was undertaken to better characterise the lesions. Twelve fetlock joints were collected and all had more than one bone abnormality on US. Normal subchondral bone appeared on US as a well-defined and regular hyperechoic line with distal acoustic shadowing. Bone abnormalities detected on US included (1) gaps in the proximal subchondral bone filled wi...
Finnegan CM, Townsend NB, Barnett TP, Barakzai SZ.Involvement of the ventral conchal sinus (VCS) is an important diagnostic and prognostic feature in cases of the equine sinus disease. The authors aimed to ascertain if the caudo-dorsal extension of the VCS, the ventral conchal bulla (VCB) is identifiable on plain radiographs of cadaver skulls without sinus disease. Bilateral frontonasal sinus flaps were made in 10 equine cadaver skulls. Plain lateral, lateral oblique and dorso-ventral radiographs were then obtained followed by the same views taken with stainless steel wire outlining the caudal border of the VCB. Plain radiographs were randomi...
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...
O'Brien T, Baker TA, Brounts SH, Sample SJ, Markel MD, Scollay MC, Marquis P, Muir P.To compare digital radiography (DR), computed tomography (CT), and magnetic resonance imaging (MRI) for detection of pathology of the distal aspect of the third metacarpal bone (MC3) and to assess whether arthrography would improve detection of articular cartilage or subchondral bone cracking. Methods: Cross-sectional study. Methods: Limb specimens from 17 Thoroughbred horses after catastrophic injury and 4 age-matched control horses. Methods: Standard DR, CT, and MRI images of the metacarpophalangeal joint were acquired before and after iohexol injection. Pathologic features detected with ima...
Beccati F, Pepe M, Di Meo A, Davanzo S, Moriconi F.To evaluate changes in the cortical bone of the proximal phalanx of the fore-limbs of Thoroughbreds in response to training. Methods: Twenty-seven 2-year-old Thoroughbreds (20 females, 2 males, and 5 geldings). Methods: Horses were principally in training for races in a straight line and in a clockwise direction. Lateromedial and dorsopalmar radiographic views of each metacarpophalangeal joint were obtained before the horses started training and 1 year after starting exercise and racing. Width of the dorsal, palmar, lateral, and medial cortex and the width and thickness of the medulla were mea...
Abdunnabi AH, Ahmed YA, Philip CJ, Davies HM.There is scant morphological data for equine carpal bones despite the frequent pathology in Thoroughbreds (TB). This study aimed to identify morphological and morphometrical variations and similarities in carpal bones between and within TB and Ponies (Po). Carpal bones from nine TB and 13 Po were prepared by boiling and drying. Lateromedial width, dorsopalmar depth, proximodistal height, relative density and volume of each bone were measured. Normalized measurements of the radial (Cr) and third (C3) carpal bones were significantly different in all dimensions, and there were significant variati...
Skedros JG, Sybrowsky CL, Anderson WE, Chow F.Natural loading of the calcanei of deer, elk, sheep and horses produces marked regional differences in prevalent/predominant strain modes: compression in the dorsal cortex, shear in medial-lateral cortices, and tension/shear in the plantar cortex. This consistent non-uniform strain distribution is useful for investigating mechanisms that mediate the development of the remarkable regional material variations of these bones (e.g. collagen orientation, mineralization, remodeling rates and secondary osteon morphotypes, size and population density). Regional differences in strain-mode-specific micr...
Schmidburg I, Pagger H, Zsoldos RR, Mehnen J, Peham C, Licka TF.Laterolateral radiographs of equine necks are reported to be inaccurate in determining the site of spinal cord lesions even when a myelogram is carried out. The goal of this study was to assess constrictions present in the cervical vertebral canal at any time point throughout the extremes of movement. Sixteen equine cervical vertebral columns without history of cervical disease were used. After removal of the spinal cord, the dura mater was filled with polyurethane foam and during its plastic phase the cervical vertebral column was passively moved in flexion-extension, lateral bending and 30°...
Artese L, Piattelli A, Di Stefano DA, Piccirilli M, Pagnutti S, D'Alimonte E, Perrotti V.The aim of the present study was to perform a comparative histological and immunohistochemical evaluation of microvessel density, vascular endothelial growth factor, and nitric oxide synthase (NOS) expression in sinus augmentation using autologous bone alone or in combination with equine bone. Methods: Sixteen patients underwent sinus augmentation with autologous bone and a 50:50 mixture of autologous and equine bone. Control cores were harvested from preexisting nonaugmented bone under the sinus floor. The specimens were processed for immunohistochemistry. Results: The greatest values of micr...
Nagy A, Dyson S.There is limited information on magnetic resonance imaging (MRI) findings in the carpus and proximal metacarpal region of lame horses. Objective: To document MRI findings in horses with lameness localised to the carpus and/or proximal metacarpal region. Methods: Clinical records of horses that underwent MRI of the carpus and/or proximal metacarpal region at the Animal Health Trust between January 2003 and September 2010 were reviewed. Magnetic resonance images of all horses and available radiographs, ultrasonographic and scintigraphic images were assessed. When possible, MRI findings were rela...
Raes EV, Bergman EH, van der Veen H, Vanderperren K, Van der Vekens E, Saunders JH.To compare computed tomography (CT) images of equine tarsi with cross-sectional anatomic slices and evaluate the potential of CT for imaging pathological tarsal changes in horses. Methods: 6 anatomically normal equine cadaveric hind limbs and 4 tarsi with pathological changes. Methods: Precontrast CT was performed on 3 equine tarsi; sagittal and dorsal reconstructions were made. In all limbs, postcontrast CT was performed after intra-articular contrast medium injection of the tarsocrural, centrodistal, and tarsometatarsal joints. Images were matched with corresponding anatomic slices. Four tar...
Mizuno K, Nagatani Y, Yamashita K, Matsukawa M.Ultrasound propagation in cancellous bone (porous media) under the condition of closed pore boundaries was investigated. A cancellous bone and two plate-like cortical bones obtained from a racehorse were prepared. A water-immersion ultrasound technique in the MHz range and a three-dimensional elastic finite-difference time-domain (FDTD) method were used to investigate the waves. The experiments and simulations showed a clear separation of the incident longitudinal wave into fast and slow waves. The findings advance the evaluation of bones based on the two-wave phenomenon for in vivo assessment...
Vallance SA, Spriet M, Stover SM.To enhance understanding of the nature and pathogenesis of scapular fractures in racehorses. Objective: Scapular fractures in racehorses have a consistent configuration related to sites of pre-existing stress modelling and remodelling. Methods: Fractured and intact scapulae collected post mortem were examined visually and with computed tomography (CT). Scapular fracture configuration, bone modelling changes and standardised CT morphometry and density measurements were recorded. Statistical comparisons were made between fractured, nonfractured contralateral and control scapulae. Results: Thirty...
Firth EC, Rogers CW, van Weeren PR, Barneveld A, McIlwraith CW, Kawcak CE, Goodship AE, Smith RK.This study recorded the response to training of the diaphysis of the proximal phalangeal bone and the third metacarpal bone (Mc3) and the Mc3 proximal metaphysis. Nineteen 2- and 3-year old horses in training were exposed either to spontaneous exercise at pasture (PASTEX group) or additional imposed exercise (CONDEX group) from a very young age. Quantitative computed tomography scans were analysed for bone mineral content, size, bone mineral density, periosteal and endosteal circumference, cortical thickness and an estimate of bone strength. The bones of the CONDEX horses were bigger and stron...
Wright IM, Minshall GJ.Although a well recognised clinical entity, only small numbers of osteochondromata on the caudal distal radius have previously been published and its occurrence in young racing Thoroughbreds has not previously been reported. Identification and management of associated lesions in the deep digital flexor tendon have received scant attention in the literature. Objective: Osteochondromata of the caudal distal radius occur commonly in young racing Thoroughbreds. They vary in size and location, sagittally and proximodistally, but the majority cause impingement damage to the deep digital flexor tendo...
Dyson S, Nagy A, Murray R.Eight sports horses with unilateral (4) or bilateral (3) forelimb or unilateral hindlimb (1) lameness had subtle radiologic abnormalities of the subchondral bone of the sagittal groove of the proximal phalanx associated with moderate or intense increased radiopharmaceutical uptake. High-field or low-field magnetic resonance (MR) imaging confirmed the presence of a fissure fracture or subchondral and trabecular bone trauma. Seven of eight lesions were located approximately midway between the dorsal and palmar cortices of the proximal phalanx; the eighth was sited more dorsally. Two horses under...
Auer JA, Watkins JP.Fifteen cases of radial fractures in adult horses weighing more than 300 kg are discussed. Four of the horses were destroyed on humane grounds immediately because of a poor prognosis and expense of internal fixation; and two horses at five days and five weeks, respectively after treatment by cast application was initiated. Internal fixation was used in nine horses but of these only two horses recovered completely and resumed their former activities. In eight cases, two plates were applied, one lateral or medial and the other cranial. The internal fixation techniques of all nine horses were scr...
Labens R, Innocent GT, Voûte LC.Various radiographic rating scales have been described for use in horses with distal tarsal osteoarthritis but little information is available on their reliability. The aim of this study was to develop a radiographic rating scale based on the results of an expert consultation process (the Delphi process), and to test the reliability of the radiographic rating scale. Seven radiographic features were identified as important indicators of distal tarsal osteoarthritis and these were then incorporated in the radiographic rating scale, which used a 100-mm-long visual analog scale. On two occasions n...
McCarty CA, Thomason JJ, Gordon K, Hurtig M, Bignell W.To add to the existing data on impact loading of the metacarpophalangeal (MCP) joint as a precursor to assessing the potential role of impact in joint disease. Objective: To examine the effect of impact loading on contact areas of the first phalanx (P1) and proximal sesamoids (PS) with the third metacarpal (McIII) under 3 hoof-strike conditions (toe-first, flat, heel-first). Methods: Randomised, repeated controlled experiment using cadaver material. Methods: Eight cadaver limbs were subjected to randomised, repeated controlled trials where the hoof was struck by a pendulum impact machine (impa...
Vallance SA, Spriet M, Stover SM.To enhance understanding of the nature and pathogenesis of scapular fractures in racehorses. Objective: Scapular fractures in racehorses have a consistent configuration related to sites of pre-existing stress modelling and remodelling. Methods: Fractured and intact scapulae collected post mortem were examined visually and with computed tomography (CT). Scapular fracture configuration, bone modelling changes and standardised CT morphometry and density measurements were recorded. Statistical comparisons were made between fractured, nonfractured contralateral and control scapulae. Results: Thirty...
Cheetham J, Nixon AJ.To identify sites for arthroscopic access to the palmar aspects of the antebrachiocarpal (AC) and middle carpal (MC) joints, and describe visible carpal bone surfaces for each approach. Methods: Prospective experimental study. Methods: Equine carpi: 16 cadavers, 8 live horses. Methods: A latex model was used to identify possible sites for arthroscopic access to the palmar aspects of the AC and MC joints. Carpi (n = 24) were examined arthroscopically and arthroscopic access sites and visible carpal bone surfaces were described. Results: Arthroscopic approaches and instrument portals were develo...
Bassage LH, Richardson DW.To determine type, distribution, and radiographic appearance of condylar fractures of the third metacarpal bone (MC-3) or third metatarsal bone (MT-3) in Thoroughbreds (TB), Standardbreds (SB), and Arabians, to assess long-term outcome of horses in which fractures were repaired surgically, and to identify variables associated with prognosis for return to racing. Methods: Retrospective study. Methods: 224 horses with 233 fractures. Methods: Medical records and radiographs obtained before and after treatment were reviewed. Racing performance before and after treatment was determined by reviewing...
Ferguson VL, Bushby AJ, Firth EC, Howell PG, Boyde A.Impact exercise has a profound effect in increasing volumetric density of epiphyseal bone, as clearly shown in 2 year old thoroughbred racehorses from which we derived the tissue studied in the present investigation. Here, we asked the question whether the fabric-level properties of the mineralised tissues immediately below hyaline articular cartilage which transmit the extra loads are themselves altered in consequence. We therefore studied the nanoindentation elastic modulus and its relationship to the concentration of mineral determined by quantitative backscattered electron imaging in the h...
Osborn ML, Cornille JL, Blas-Machado U, Uhl EW.Navicular syndrome has been traditionally characterized by progressive lameness with chronic degeneration of the navicular bone. Advances in imaging techniques have revealed that its associated soft tissue structures are also affected. This distribution of lesions is explained by conceptualizing the equine navicular apparatus as an enthesis organ that facilitates the dissemination of mechanical stress throughout the tissues of the foot. The navicular apparatus has the same structural adaptations to mechanical stress as the human Achilles tendon complex. These adaptations efficiently dissipate ...
Belyaev RI, Kuznetsov AN, Prilepskaya NE.The vertebral column is a hallmark of vertebrates; it is the structural basis of their body and the locomotor apparatus in particular. Locomotion of any vertebrate animal in its typical habitat is directly associated with functional adaptations of its vertebrae. This study is the first large-scale analysis of mobility throughout the presacral region of the vertebral column covering a majority of extant odd-toed ungulates from 6 genera and 15 species. In this study, we used a previously developed osteometry-based method to calculate available range of motion. We quantified all three directions ...
Singer E, Garcia T, Stover S.Sagittal fractures of the proximal phalanx (P1) in the racehorse appear to be associated with turf racing surfaces, which are known to restrict forward slide of the foot at impact. We hypothesized that restriction of forward foot slip would result in higher P1 bone strains during metacarpophalangeal joint (MCPJ) hyperextension. Unilateral limbs from six equine cadavers were instrumented with strain gauges and bone reference markers to measure dorsoproximal P1 bone strains and MCPJ extension, collateromotion and axial rotation during in vitro limb loading to 10,500 N. By limiting movement of th...
Mellish MA, Lucas ZN, Puchalski SM, Kusch TA.Laminitis is a painful condition that causes lameness in horses. However, monitoring this condition in feral horses is logistically difficult. Laminitis can be detected postmortem, as inflammation of the sensitive laminae of the hoof changes the relative location of the bony structures within the hoof capsule. Thus, evaluation of cadavers may be used to estimate laminitis prevalence in feral populations of horses. The objective of this study was to estimate the prevalence of laminitis in feral horses inhabiting the Sable Island National Park Reserve, Canada, using radiographic imagery on the h...
Glade MJ.Skeletal homeostasis during late gestation, lactation, and the post-lactational recovery period is poorly understood. In an experiment using an animal model (the horse), metacarpal breaking strengths (MBS) estimated via transmission ultrasonics were examined during the last 12 weeks of gestation and for 40 weeks after parturition. MBS increased during the last 6-10 weeks of gestation in mares fed amounts of calcium (Ca) recommended by the National Research Council; maximum MBS coincided with the week of parturition. In contrast, MBS in mares fed 20% less Ca remained relatively constant during ...
Frank N, Hawkins JF, Couëtil LL, Raymond JT.A 17-year-old pony mare was admitted for evaluation of progressive enlargement of the facial bones during the preceding 9 months. Laboratory testing revealed that the pony had hypercalcemia, hypophosphatemia, high urinary fractional excretion of phosphorus, and high serum concentration of intact parathyroid hormone (185.1 pmol/L; reference range, 0.25 to 2.0 pmol/L). On the basis of these findings, a diagnosis of primary hyperparathyroidism was made by ruling out nutritional secondary hyperparathyroidism, chronic renal disease, and pseudohyperparathyroidism resulting from neoplasia. Although p...
Leitch M.Angular limb deformities are not uncommon in foals. Mild angular deviation due to laxity of supporting soft tissues often resolves spontaneously. However, external splinting or casting may be needed in severe cases or in those that do not resolve. When incomplete ossification of carpal or tarsal bones is the cause of the limb deformity, external support is mandatory to prevent further deformation and abnormal development of the bones. When epiphyseal and metaphyseal abnormalities cause axial deviation, surgical intervention is usually necessary. Circumferential periosteal transection and/or tr...
Vervuert I, Coenen M, Wedemeyer U, Harmeyer J.Seven untrained Standardbred horses were used in a training programme of 6 weeks to evaluate the effects of exercise and training on bone metabolism. The horses were exercised on a treadmill according to a standardized exercise test (SET 1: six incremental steps, 5 min duration each; start 5 m/s, increase 1 m/s). SET 1 was followed by a training programme of 6 weeks. In alternating order: high-speed exercise (HSE): 15 min duration, start at VLa4, continuous increase in speed every 60 s by 0.3 m/s (14 incremental steps); low-speed exercise (LSE): constant velocity at VLa2.5, duration: approxima...
Holcombe SJ, Schneider RK, Bramlage LR, Gabel AA, Bertone AL, Beard WL.Medical records of 59 racehorses with noncomminuted midsagittal proximal phalanx fractures repaired by means of lag screw fixation between 1973 and 1991 were reviewed. Fractures were classified as short incomplete fractures (7), long incomplete fractures (32), complete fractures extending into the proximal interphalangeal joint (13), and complete fractures extending through the lateral cortex of the proximal phalanx (7). Time from fracture repair to first race following fracture repair, number of racing starts, and fastest race times before and after surgery were obtained from race records and...
Jeffcott LB, McCartney RN, Speirs VC.A safe, non-invasive method for the accurate measurement of bone mineral content in the third metacarpal bone of the horse is described. The technique involves scanning the bone with a single photon beam from an Americium-241 source. Data were obtained from the excised metacarpal bones from both forelimbs of 50 normal and seven lame horses. Measurements were made in vivo on eight normal and seven lame horses and on one experimental horse with osteopenia induced by partial weightlessness in a flotation tank. In the normal horses bone mineral content altered with age, particularly in the first s...
Whitty JA, Miller AV, Miller AD, Carney PC, Scrivani PV.The styloid process sheath (SPS) is a part of the tympanic temporal bone and an incomplete bony sleeve surrounding the styloid process, tympanohyoid cartilage, and dorsal part of the stylohyoid bone. In horses undergoing head CT, we observed a range of SPS sizes and questioned whether differences were early features of temporohyoid osteoarthropathy (THO) or normal anatomic variations associated with age, body weight, sex, or breed. We hypothesized that SPS sizes were positively correlated with age and body weight, but not with sex or breed. Using a convenience population of horses that underwe...
Rijkenhuizen AB, Nemeth F, Dik KJ, Goedegebuure SA.An arteriographic and histological study of the arterial blood supply of 35 navicular bones, from 19 adult horses with no clinical or radiographical signs of navicular disease, is described. The arteries enter the navicular bone from four directions: distal, proximal, medial, and lateral. The navicular bone can be divided into areas which receive arteries from one, two, or three directions, whereas the distal supply covers the largest part of the navicular bone. The distal arteries enter the navicular bone through the nutrient foramen which contains loose connective tissue, nutrient vessels an...
Cornelissen BP, van Weeren PR, Ederveen AG, Barneveld A.Bone mineral density (BMD) and cross-sectional area (CSA), measured using peripheral quantitative computed tomography, were determined in the left third metacarpal bone (MCIII) and left medial proximal sesamoid bone (psb) in 3 differently exercised groups of foals. Group(box) (n = 14) was confined to a box stall from birth to age 5 months, Group(training) (n = 14) was kept in similar box stalls but additionally given a daily exercise programme consisting of an increasing number of gallop sprints and Group(pasture) (n = 15) remained at pasture. At 5 months of age, 8 foals from each group were r...
Bogers SH, Rogers CW, Bolwell C, Roe W, Gee E, McIlwraith CW.To compare regional proportions and spatial distributions of volumetric bone mineral density (BMDv) of the palmar aspect of the distal epiphysis of the third metacarpal bone (McIII) in limbs with or without a condylar fracture from Thoroughbred racehorses. Methods: McIIIs from cadavers of Thoroughbred racehorses with (n = 6 bones) and without (8) a condylar fracture. Methods: BMDv and spatial distributions of BMDv in peripheral quantitative CT images of the distal epiphysis of McIIIs were quantitatively assessed with spatial analysis software. Relative proportions of voxels within 9 threshold ...
Tessier C, Brühschwein A, Lang J, Konar M, Wilke M, Brehm W, Kircher P.Diseases of paranasal sinuses and nasal passages in horses can be a diagnostic challenge because of the complex anatomy of the head and limitations of many diagnostic modalities. Our hypothesis was that magnetic resonance (MR) imaging would provide excellent anatomical detail and soft tissue resolution, and would be accurate in the diagnosis of diseases of the paranasal sinuses and nasal passages in horses. Fourteen horses were imaged. Inclusion criteria were lesions located to the sinuses or nasal passages that underwent MR imaging and subsequent surgical intervention and/or histopathologic e...
Couroucé-Malblanc A, Leleu C, Bouchilloux M, Geffroy O.Developmental orthopaedic lesions are commonly found in French Standardbred horses. One of the main questions asked by trainers, owners and veterinarians is what impact these lesions have on the racing career and racing performances of horses. Objective: To study the prevalence and distribution of developmental orthopaedic lesions in young French Standardbred trotters and to relate them to racing performance. Methods: Feet, fetlock, tarsus and stifle regions were radiographed in 865 two-year-old French Standardbred trotters. Abnormal radiographic findings (ARF) were evaluated for 12 anatomical...
Delguste C, Doucet M, Gabriel A, Guyonnet J, Lepage OM, Amory H.This study assessed the feasibility of measuring tiludronate in horses using a minimally invasive bone biopsy technique. Eight horses were treated with intravenous (IV) tiludronate [1 mg/kg bodyweight (BW)], either once (n = 4) or twice, 28 d apart (n = 4). The horses that were treated once were euthanized on days 1, 43, 57, or 92 and those that were treated twice, were euthanized on days 112, 154, 194, or 364. Bone samples were taken bilaterally from each horse at 4 sites: the third metacarpal bone (MCIII), the 13th rib (R13), the tuber coxae (TC), and the cuboid bone (CB). Test samples were ...
Young DR, Nunamaker DM, Markel MD.Eight untrained 2-year-old Thoroughbred horses were used in a study of the remodeling response of the proximal sesamoid bone (PSB) to training-related stimuli. Two horses each were assigned to 1 of 4 groups: group 1, untrained, pasture turnout (control); group 2, modified-classically trained, dirt track; group 3, classically trained, dirt track; and group 4, classically trained, wood chip track. Horses were given fluorochromic bone labels every 28 days during training. All horses were euthanatized after 5 months of training, and the proximal sesamoid bones (PSB) were removed. A midsagittal sec...
Fontaine P, Blond L, Alexander K, Beauchamp G, Richard H, Laverty S.Osteochondrosis dissecans (OCD) is a focal failure of endochondral ossification of the epiphysis characterized by the presence of cartilage flaps and osteochondral fragments. The objective of this study was to image epiphyseal development in the equine pelvic limb to determine whether there was a variation in site maturation that could be a predisposing factor for OCD. Pelvic limbs (fetuses and foals) were studied post-mortem. The epiphyses of the distal femur, tibia and talus were scanned with computed tomography (CT) and 1.5T magnetic resonance imaging (MRI) to investigate the degree and pat...
Spriet M, Arndt S, Pige C, Pye J, O'Brion J, Carpenter R, Blea J, Dowd JP.This retrospective, methods comparison study aimed to compare skeletal scintigraphy and F-NaF positron emission tomography (PET) for the detection of abnormalities in the fetlocks of Thoroughbred racehorses. Thirty-three horses (72 limbs) imaged with both scintigraphy and F-NaF PET, for investigation of lameness or poor performance related to the fetlock, were included. Seven observers, including experienced racetrack practitioners, surgery and imaging residents, and a board-certified veterinary radiologist, independently reviewed all data for evidence of increased radiopharmaceutical uptake...
Dyson S.Nuclear scintigraphic examination of equine athletes has a potentially important role in the diagnosis of lameness or poor performance, but increased radiopharmaceutical uptake (IRU) is not necessarily synonymous with pain causing lameness. Nuclear scintigraphy is highly sensitive to changes in bone turnover that may be induced by loading and knowledge of normal patterns of RU is crucial for accurate diagnosis. Blood pool images can be useful for identification of some soft tissue injuries, although acute bone injuries may also have intense IRU in blood pool images. Some muscle injuries may be...
Minshall GJ, Wright IM.Accurate radiological and ultrasonographic descriptions of frontal plane fractures of the accessory carpal bone (ACB) are lacking, and implications of these fractures for the carpal sheath and its contents have not previously been reported. Objective: Aims were as follows: 1) to describe the location and radiological features of frontal plane fractures of the ACB; 2) to document communication of displaced fractures with the carpal sheath and consequent injury to the deep digital flexor tendon (DDFT); 3) to describe ultrasonographic identification of lesions; and 4) to report tenoscopic evaluat...
Désévaux C, Laverty S, Doizé B.To develop a technique for sternal bone biopsy in standing horses. Methods: Experimental study. Methods: Five adult horses. Methods: Horses were restrained in a standing stocks and sedated. The sternal biopsy site, identified by ultrasonographic examination, was clipped and prepared for aseptic surgery and infiltrated with local anesthetic. An electric bone biopsy drill (Osteocore; Institut Straumann AG, CH-4437, Waldenburg, Switzerland)), which yielded 4-mm-diameter bone specimens, was used to obtain sternal biopsies through a small skin incision. Sections (7 microm) of the bone specimens wer...
