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.
Ramzan PH, Palmer L.Musculoskeletal injury is the most common cause of lost training days in the young Thoroughbred horse in flat race training. To date, there has been little investigation of the regional patterns of injury frequently observed by clinicians in racehorse practice. The present study was conducted to determine incidence of musculoskeletal injuries in Thoroughbreds in training in Newmarket, United Kingdom. Veterinary records for all horses resident in three large (>100 horse) training yards were assessed for occurrence of significant musculoskeletal injury. A total of 248 injuries were recorded in 2...
Cousty M, Retureau C, Tricaud C, Geffroy O, Caure S.The radiographs of 102 French trotters presented with signs of back pain were reviewed retrospectively, and a control group of 16 French trotters without back pain was analysed. The age, sex, type of race, number of starts, earnings and index of performance were recorded. Radiological evaluation was performed from the 14th thoracic (T14) to the third lumbar (L3) vertebra. Impingement of the spinous processes (ISP), periarticular proliferation of synovial intervertebral articulations (PP-SIA) and sclerosis of SIA (S-SIA) were located and graded. Radiological lesions were identified in 10 (62 pe...
Raes EV, Vanderperren K, Pille F, Saunders JH.Ultrasonographic findings from 100 horses (103 joints) diagnosed with tarsal region pathology are described. Results of standard orthopaedic, radiographic and ultrasonographic examination of the tarsal region were analysed retrospectively. Periarticular swelling and/or synovial effusion was present in 100% of the joints, a wound was observed in 14.5% and 76.7% of the horses that were lame. Abnormalities were detected in 69.7% of joints using radiography and in 100% with ultrasonography. Our results show that the main disease process can affect all aspects of the tarsus. The most common ultraso...
Galvin N, Corley K.A retrospective study was carried out to investigate the causes of disease and death in a population of foals in Ireland during their first 12 months post partum. Foaling and veterinary records from 343 foals on four farms born between January 1, 2004 and May 30, 2008 were reviewed. Among 343 foals, 22 did not survive to 12 months of age. Over the five-year period, the incidence of stillbirth was 1.5% (5/343), mortality 5% (17/338) and overall morbidity was 88.5% (299/338). Morbidity was calculated to include all new conditions brought to the attention of the attending veterinary surgeon, no m...
Winter MD, Berry CR, Reese DJ.Nuclear scintigraphy has been used successfully for various applications in horses in the past 30 years. Many private practices and most veterinary schools have gamma cameras, which are used to image an injected radionuclide in an equine patient. Unique exercise-related demands place specific physiologic stressors on the musculoskeletal system of horses. Horses are often pushed beyond normal physiologic limits because of specific performance stresses; therefore, injury to their musculoskeletal system is common. Skeletal scintigraphy is exceedingly sensitive but relatively nonspecific for deter...
McGivney BA, Eivers SS, MacHugh DE, MacLeod JN, O'Gorman GM, Park SD, Katz LM, Hill EW.Selection for exercise-adapted phenotypes in the Thoroughbred racehorse has provided a valuable model system to understand molecular responses to exercise in skeletal muscle. Exercise stimulates immediate early molecular responses as well as delayed responses during recovery, resulting in a return to homeostasis and enabling long term adaptation. Global mRNA expression during the immediate-response period has not previously been reported in skeletal muscle following exercise in any species. Also, global gene expression changes in equine skeletal muscle following exercise have not been reported...
Desantis S, Ventriglia G, Zizza S, Guaricci AC, Losurdo M, Zarrilli A, Albrizio M.The presence of the mu-opioid receptor (MOR) was investigated in the mare oviduct during oestrus and anoestrus, by means of immunoblotting and immunohistochemistry. Immunoblotting analysis showed that the MOR protein is expressed as 65, 50 and 30 kDa forms in the infundibulum and ampulla both in oestrus and anoestrus, while the 30 kDa form is absent in the isthmus. Moreover, different levels of expression were observed along the ampulla in the two periods examined. Immunohistochemistry revealed MOR in the mucosal epithelium, stromal cells, myocytes and blood vessels. Ciliated cells expressed M...
Brink P, Dolvik NI, Tverdal A.The presence and degree of tarsocrural joint effusion and lameness, and the result of a hindlimb flexion test were scored subjectively in 79 horses before, and six weeks to 20 months after, arthroscopic surgery to remove osteochondritis dissecans fragments. The scores of all three variables improved significantly after surgery. The score reductions for the right and left hindlimbs, respectively, were 82 per cent and 95 per cent for lameness, 48 per cent and 41 per cent for joint effusion, and 89 per cent and 84 per cent for reaction to flexion (P < or = 0.01). The oldest horses reacted more fa...
Smith AJ, Felstead CW, Lawson JS, Weller R.Radiography is the most commonly applied imaging modality in equine practice and forms an essential part of the diagnostic work-up of lame horses. Radiographic signs of musculoskeletal pathology are frequently localized at sites of soft tissue attachment, which are often not clearly visible on radiographs. Different lesions carry different prognoses and require a variety of treatments, and a good knowledge of the position of the synovial structures in the distal limb of the horse is essential for practitioners in the interpretation of radiographs. This study describes a new technique for creat...
Nagy A, Dyson S.While low-field magnetic resonance (MR) images can provide useful information in the investigation of proximal metacarpal region pain, an in-depth knowledge of anatomy and comparison with more detailed high-field images are essential to understand the meaning of different signal intensities within tissues. This anatomic description is based on low-field and high-field MR examination of 30 cadaver metacarpal regions of mature horses with no history of carpal or proximal metacarpal pain. Normal MR anatomy is described and is illustrated by high-field and low-field MR images in transverse, sagitt...
Tabar-Rodriguez JJ, Cruz AM, Monteith G, Gordon K, Hurtig MB.OBJECTIVE-To use quantitative ultrasonography to evaluate the association between the speed of sound (SOS) at 9 sites in the third metacarpal bone (MCIII) of racing Thoroughbreds with workload accumulation and the effect that MCIII failure has on this association. ANIMALS-Sixty-two 2- and 3-year-old Thoroughbreds in racing condition. PROCEDURES-Cumulative work index (CWI) was used to calculate total workload (CWI(total)) and also 3 independent CWIs for the various gaits (ie, trot [CWI(trot)], gallop [CWI(gallop)], and race [CWI(race)]) used during training and racing. Speed of sound was monito...
Tranquille CA, Blunden AS, Dyson SJ, Parkin TD, Goodship AE, Murray RC.OBJECTIVE-To investigate effects of exercise on hyaline cartilage (HC), calcified cartilage (CC), and subchondral bone (SCB) thickness patterns of equine tarsi. SAMPLE POPULATION-30 tarsi from cadavers of horses with known exercise history. PROCEDURES-Tarsi were assigned to 3 groups according to known exercise history as follows: pasture exercise only (PE tarsi), low-intensity general-purpose riding exercise (LE tarsi), and high-intensity elite competition riding exercise (EE tarsi). Osteochondral tissue from distal tarsal joints underwent histologic preparation. Hyaline cartilage, CC, and SCB...
Trope GD, Whitton RC.A 12-year-old show-jumping mare was presented for investigation of a chronic hindlimb lameness of 16 weeks duration. Perineural anaesthesia and ultrasonography localised the lesion to the medial collateral ligament of the distal interphalangeal joint of the left hindlimb. Treatment consisted of a heavily padded distal limb cast for 6 weeks, strict box rest and a strictly regulated hand walking program. Serial ultrasonographic examinations were performed throughout the rehabilitation period. Collateral ligament desmitis of the distal interphalangeal joint is a commonly diagnosed condition of th...
de Cocq P, Duncker AM, Clayton HM, Bobbert MF, Muller M, van Leeuwen JL.In equestrian sports, it is generally assumed that rising and sitting trot load the horse's back differently. The objective of this study was to quantify the load on the horse's back in these riding techniques. Kinematic data of 13 riders were collected in rising and sitting trot. The time-history of the position of the rider's centre of mass (CoM) was calculated, and differentiated twice to obtain the acceleration of the CoM. The reaction force between the rider and the horse's back was calculated from the acceleration. Forces were divided by the body weight of the rider to obtain dimensionle...
Bouwman FG, van Ginneken MM, Noben JP, Royackers E, de Graaf-Roelfsema E, Wijnberg ID, van der Kolk JH, Mariman EC, van Breda E.The major aim of the present study was to investigate the proteome of standardbred horses at different stages of training and intensified training. We searched for biomarkers using small skeletal muscle biopsies of live animals. 2D gel electrophoresis and mass spectrometry were successfully applied to investigate training-induced differential expression of equine muscle biopsy proteins. Despite the poor resolution of the equine genome and proteome, we were able to identify the proteins of 20 differential spots representing 16 different proteins. Evaluation of those proteins complies with adapt...
Wennerstrand J, Gómez Alvarez CB, Meulenbelt R, Johnston C, van Weeren PR, Roethlisberger-Holm K, Drevemo S.Back problems are important contributors to poor performance in sport horses. It has been shown that kinematic analysis can differentiate horses with back problems from asymptomatic horses. The underlying mechanism can, however, only be identified in a uniform, experimental setting. Our aim was to determine if induction of back pain in a well-defined site would result in a consistent change in back movement. Back kinematics were recorded at a walk and trot on a treadmill. Unilateral back pain was then induced by injecting lactic acid into the left longissimus dorsi muscle. Additional measureme...
Jalim SL, McKinnon AO, Russell TM.A Monteggia fracture is a humero-radial luxation combined with a fracture of the ulna. It is a rare injury, infrequently reported in the horse. This case report describes the surgical repair of such a fracture in a 4-month-old filly.
Eivers SS, McGivney BA, Fonseca RG, MacHugh DE, Menson K, Park SD, Rivero JL, Taylor CT, Katz LM, Hill EW.Intense selection for elite racing performance in the Thoroughbred horse (Equus caballus) has resulted in a number of adaptive physiological phenotypes relevant to exercise; however, the underlying molecular mechanisms responsible for these characteristics are not well understood. Adaptive changes in mRNA expression in equine skeletal muscle were investigated by real-time qRT-PCR for a panel of candidate exercise-response genes following a standardized incremental-step treadmill exercise test in eight untrained Thoroughbred horses. Biopsy samples were obtained from the gluteus medius before, i...
Minami Y, Yamano S, Kawai M, Hiraga A, Miyata H.To find a new parameter indicating muscle fitness in Thoroughbred horses, we examined time-dependent recovery of glycogen content and sarcoplasmic reticulum (SR) Ca(2+)-ATPase activity of skeletal muscle after intensive treadmill running. Two repeated 50-sec running sessions (13 m/sec) were performed on a flat treadmill (approximately 90%VO2max). Muscle samples of the middle gluteal muscle were taken before exercise (pre) and 1 min, 20 min, 60 min, and 24 hr after exercise. Muscle fiber type composition was determined in the pre muscle samples by immunohistochemical staining with monoclonal an...
Pagger H, Schmidburg I, Peham C, Licka T.This aim of this study was to test the hypothesis that the stiffness of the equine cervical spine depends on the direction of force applied and on spinal position. Muscles and nuchal ligament were removed from the cervical spines of 17 horses that were without a history of cervical or neurological disease. The cervical spines were then flexed/extended dorsoventrally (with the spine straight and with the occiput rotated 30° against T1) and laterolaterally. Mean dorsoventral stiffness was 297 N/m (± 135) in flexion, 1347 N/m (± 2083) in extension, 421 N/m (± 164) in lateral flexion, 279 N/m ...
Ramzan PH.Fractures involving the fetlock region are encountered commonly in Thoroughbred racehorses. Condylar fractures of the distal metacarpus/metatarsus and mid-sagittal fractures of the proximal phalanx account for the majority of fetlock injuries during both racing and training and clinical features, management and outcome of these injuries have been well described. Transverse fractures of the distal diaphysis of the third metacarpus, however, are seldom observed and have received little attention in the literature. This paper describes clinical and radiological findings associated with 6 cases en...
Brama PA, Holopainen J, van Weeren PR, Firth EC, Helminen HJ, Hyttinen MM.There is ample evidence on topographical heterogeneity of the principal biochemical components of articular cartilage over the surface of the joint and the influence of loading thereon, but no information on depth-related zonal variation in horses. Objective: To study depth-related zonal variation in proteoglycan (PG) and collagen content in equine articular cartilage. Methods: Two techniques (safranin-O densitometry and Fourier transform infrared spectroscopy) were applied to sections of articular cartilage from the proximal phalangeal bone of the metacarpophalangeal joint of 18-month-old Tho...
Gillen A, Dyson S, Murray R.The results of nuclear scintigraphic examination of the thoracolumbar synovial intervertebral articulations (facet joints) have to date been poorly documented. Objective: To establish an objective scintigraphic grading system for the facet joints; to investigate the relationship between the presence or absence of clinical signs of back pain and increased radiopharmaceutical uptake (IRU); and to compare the results of scintigraphy and radiography. Methods: Nuclear scintigraphic images of the 13th thoracic (T13) to first lumbar (L1) vertebrae were graded subjectively (visual assessment of the im...
Down SS, Henson FM.Arthropathy of the caudal cervical articular process joints (APJs) in the horse is documented as a cause of ataxia and paresis secondary to spinal cord compression. Enlargement of the caudal APJs is reported to increase with age, but there are no known associations of any other factors. No association of the degree of APJ enlargement with neurological signs seen has been documented. This study investigated the associations of cervical APJ enlargement at the C5-C6 and C6-C7 articulations with case subject details (breed, age, sex, usage) and clinical signs. Objective: To ascertain if there are ...
Brama PA, Firth EC, van Weeren PR, Tuukkanen J, Holopainen J, Helminen HJ, Hyttinen MM.Subchondral bone provides structural support to overlying articular cartilage and plays an important biomechanical role in osteochondral diseases. Mechanical features of bone correlate strongly with bone mineral density, which is directed by the loading conditions to which the tissue is subjected. Objective: To investigate the influence of physical activity levels on subchondral bone mineral density (sBMD) in foals during early development. Methods: Three groups of foals were subjected to different physical activity levels from birth until age 5 months. A proportion of these foals were subject...
Biggi M, Dyson SJ, Murray RC.Our aims were to evaluate the pattern of radiopharmaceutical uptake in horses with lameness related to the metacarpophalangeal and/or metatarsophalangeal joint and compare the results with similar information from sound horses. It was hypothesized bthat there would be a difference in radiopharmaceutical uptake between the lame and contralateral limb in unilaterally lame horses and that there would be a difference between lame and sound horses. Nuclear scintigraphic images of 43 horses with forelimb lameness and 30 horses with hindlimb lameness were evaluated. In all horses lameness was improve...
Stieger-Vanegas SM, Kippenes-Skogmo H, Nilsson E.An enostosis-like lesion was diagnosed in the left femur of a Swedish Warmblood horse that had a left hindlimb lameness of 3 weeks duration. With scintigraphy using technetium 99m-hydroxymethylene diphosphonate (99mTc-HDP) a marked regional focal increase in radioactivity was identified in the medullary cavity of the left femur. Radiographically there was a corresponding focal increase in bone opacity in the middiaphysis of the left femur. Histopathologically, a 5cm area of bone matrix was present in the diaphysis of the left femur and confirmed as an enostosis-like lesion. Enostosis-like lesi...
Nagy A, Dyson S.Cadaver carpi of 30 mature horses with no history of carpal or proximal metacarpal pain were examined using low-field (0.27 T) and high-field (1.5 T) magnetic resonance imaging (MRI). Normal MRI anatomy in transverse, sagittal, and dorsal plane images was determined by comparison with anatomical specimens and standard texts. Subchondral bone and cortical bone thickness measurements were obtained from standardised sites. There was variable subchondral bone thickness in the radius and carpal bones; subchondral bone thickness was consistently larger at dorsal compared with palmar sites in the...
Gasiorowski JC, Richardson DW.This article describes diagnostic arthroscopy and arthroscopic management of selected lesions in the standing equine patient. Details on case selection, patient and operating room preparation, and surgical technique are presented. This information will add techniques that avoid general anesthesia to the equine surgeon's armamentarium.
Turlo AJ, Cywinska A, Frisbie DD.High prevalence of musculoskeletal disorders in racehorses and its impact on horse welfare and racing economics call for improved measures of injury diagnosis and prevention. Serum biomarkers of bone and cartilage metabolism have previously shown promise in prediction of musculoskeletal injuries in horses. This study aimed to re-evaluate usability of the predictive serum biomarkers identified in North American Thoroughbred racehorses in a geographically distinct group of Polish Thoroughbreds. Results: Serum concentrations of bone and cartilage biomarkers: osteocalcin, c-terminal telopeptide of...
Swanstrom MD, Stover SM, Hubbard M, Hawkins DA.To determine the relative contributions of the muscles, tendons, and accessory ligaments to the passive force-length properties of the superficial (SDF) and deep digital flexor (DDF) myotendinous complexes. Methods: 8 cadaveric forelimbs from 6 adult Thoroughbreds. Methods: In vitro, limb configurations during slack position and myotendinous lengths during subsequent axial loading of forelimbs were recorded before and after transection of accessory ligaments. Expressions were derived to describe the force-length behavior of each muscle, tendon, and accessory ligament-tendon unit; linear stiffn...
Garcia da Fonseca RM, Evrard L, Rabba S, Salciccia A, Busoni V.Lesions of the manica flexoria are a tenoscopic finding in horses with digital flexor tendon sheath tenosynovitis. This retrospective case series study describes the ultrasonographic findings in seven horses admitted for digital flexor tendon sheath swelling associated with lameness and tenoscopic confirmation of a manica flexoria tear. Six horses had a partial manica flexoria tear, one a complete rupture. The ultrasonographic examination included a static examination on the weight and non-weight bearing limb and a dynamic limb assessment during flexion and extension. The main ultrasonographic...
Lee HY, Kim JY, Kim KH, Jeong S, Cho Y, Kim N.Horses have been studied for exercise function rather than food production, unlike most livestock. Therefore, the role and characteristics of tissue landscapes are critically understudied, except for certain muscles used in exercise-related studies. In the present study, we compared RNA-Seq data from 18 Jeju horse skeletal muscles to identify differentially expressed genes (DEGs) between tissues that have similar functions and to characterize these differences. We identified DEGs between different muscles using pairwise differential expression (DE) analyses of tissue transcriptome expression d...
MacGregor CM.Radiographic examination of the navicular bones of 258 horses was carried out. Of these 258 horses, 83 were sound (Group A), 151 had been diagnosed clinically as having navicular disease (Group B), and 24 had a forefoot lameness of unknown aetiology (Group C). Seven basic shapes of distal nutrient foramina were identified from these radiographs. A scoring system was then developed based on these different types of distal nutrient foramina. When this scoring system was applied to the radiographs of the 258 horses examined significant differences were found between the mean navicular scores of t...
Fowlie JG, O'Neill HD, Bladon BM, O'Meara B, Prange T, Caron JP.The conventional arthroscopic approach to the palmar/plantar aspect of the distal interphalangeal joint (DIPJ) may result in the inadvertent penetration of the digital flexor tendon sheath (DFTS) and the navicular bursa (NB). This iatrogenic communication would be undesirable subsequent to arthroscopic lavage of a septic DIPJ. Objective: A lateral/medial approach to the palmar/plantar aspect of the DIPJ will result in a significantly lower rate of inadvertent penetration of the DFTS and NB, whilst still providing adequate intra-articular evaluation. Methods: The conventional palmar/plantar app...
Gillis CL, Meagher DM, Pool RR, Stover SM, Craychee TJ, Willits N.The forelimb superficial digital flexor (SDF) tendons of 6 Thoroughbreds were examined clinically and ultrasonographically during the first 4 months of race training. Sonograms were interpreted clinically and by use of computer-aided analysis. Tendon tissue from all horses was examined histologically at the end of the study. Computer-aided analysis of sonograms of the SDF tendons revealed trends toward an increase in mean cross-sectional area and a decrease in mean echogenicity over time with training. An inverse relation was found between increase in cross-sectional area and decrease in mean ...
Symons JE, Hawkins DA, Fyhrie DP, Upadhyaya SK, Stover SM.The metacarpophalangeal joint (fetlock) is the most commonly affected site of racehorse injury, with multiple observed pathologies consistent with extreme fetlock dorsiflexion. Race surface mechanics affect musculoskeletal structure loading and injury risk because surface forces applied to the hoof affect limb motions. Race surface mechanics are a function of controllable factors. Thus, race surface design has the potential to reduce the incidence of musculoskeletal injury through modulation of limb motions. However, the relationship between race surface mechanics and racehorse limb motions is...
Gideon L.A discussion of the merits of acupuncture therapy and a review of experiments that support the neurogenic mediation of acupuncture are presented. Case reports are included as examples of the therapeutic value of acupuncture in treatment of intestinal and musculoskeletal disorders in the horse. Statistical importance cannot be credited to the clinical experiences reported here because of the small number of cases. Hopefully, the clinical success reported will encourage continued investigation of the clinical efficacy and adjunctive value of acupuncture in the veterinary profession.
Mäenpää PE, Pirskanen A, Koskinen E.Serum alkaline phosphatase activity and serum concentrations of osteocalcin, free thyroxine, protein, and cholesterol were measured in 14 foals monthly from birth to 1 year of age. A transient decrease (P less than 0.05) in alkaline phosphatase activity and osteocalcin, free thyroxine, and cholesterol concentrations was found in November after transferring the horses from pasture to stables for the winter months. During the 2 subsequent months, serum alkaline phosphatase activity and osteocalcin concentration increased slightly. Protein concentration was highest in late fall and decreased (P l...
Sander J, Terhardt M, Janzen N, Renaud B, Kruse CJ, François AC, Wouters CP, Boemer F, Votion DM.Equine atypical myopathy is caused by hypoglycin A (HGA) and methylenecyclopropylglycine (MCPrG), the known protoxins of sycamore maple (Acer pseudoplatanus). Various tissues from five atypical myopathy cases were analyzed but only HGA was found. Whether deamination of MCPrG has already occurred in the intestine as the first stage of metabolization has not been investigated. Activation of the protoxins to methylenecyclopropylacetyl (MCPA)-CoA and methylenecyclopropylformyl (MCPF)-CoA, respectively, occurred mainly in the skeletal muscles, as evidenced by very high concentrations of MCPA-carnit...
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...
Kruse CJ, Stern D, Mouithys-Mickalad A, Niesten A, Art T, Lemieux H, Votion DM.Equine atypical myopathy is a seasonal intoxication of grazing equids. In Europe, this poisoning is associated with the ingestion of toxins contained in the seeds and seedlings of the sycamore maple (Acer pseudoplatanus). The toxins involved in atypical myopathy are known to inhibit ß-oxidation of fatty acids and induce a general decrease in mitochondrial respiration, as determined by high-resolution respirometry applied to muscle samples taken from cases of atypical myopathy. The severe impairment of mitochondrial bioenergetics induced by the toxins may explain the high rate of mortality obs...
Pluim M, Martens A, Vanderperren K, van Weeren R, Oosterlinck M, Dewulf J, Kichouh M, Van Thielen B, Koene MHW, Luciani A, Plancke L, Delesalle C.High-power laser therapy is often used as a treatment for human sport injuries but controlled standardized studies on its efficacy are lacking. The technique has also been introduced in the equine field and recently promising results were reported in a retrospective study focusing on 150 sporthorses suffering from tendinopathy and desmopathy of the SDFT, DDFT, suspensory ligament, and suspensory branches. The goal of the present study was to evaluate the effect of high-power laser in a standardized lesion model in horses. Lesions were created in all lateral suspensory branches of 12 warmblood ...
Hopper BJ, Steel C, Richardson JL, Alexander GR, Robertson ID.Sclerosis of the third carpal bone is a common radiographic finding in both lame and sound racehorses, but there are no guidelines correlating degree of sclerosis and incidence of lameness. Objective: To develop a protocol for describing subchondral bone sclerosis in C3 on dorsoproximal-dorsodistal oblique (DPr-DDiO) radiographs of the carpus and to correlate these changes with exercise history and carpal lameness. Methods: One hundred and six Standardbreds entering their first year of training (exercise group) and 7 age-matched Standardbreds at pasture (controls) were examined at approximatel...
Doll CU, von Pueckler K, Offhaus J, Berner D, Burk J.In equine medicine, experience regarding MRI of chronic tendon lesions is limited, and evidence on the suitability of different sequences in 3 T high-field MRI is scarce. Therefore, macroscopically healthy and altered tendons were examined by histology and in 0.27 T low- and 3 T high-field MRI, focusing on T1-weighted (T1w) sequences to visualize chronic lesions. In high-field MRI, tendons were positioned parallel (horizontal) and perpendicular (vertical) to the magnetic field, acknowledging the possible impact of the magic angle effect. The images were evaluated qualitatively and signal inten...
Nürnberger S, Rentenberger C, Thiel K, Schädl B, Grunwald I, Ponomarev I, Marlovits S, Meyer C, Barnewitz D.The present study reports for the first time the presence of giant crystals in mitochondria of equine chondrocytes. These structures show dark contrast in TEM images as well as a granular substructure of regularly aligned 1-2 nm small units. Different zone axes of the crystalline structure were analysed by means of Fourier transformation of lattice-resolution TEM images proving the crystalline nature of the structure. Elemental analysis reveals a high content of nitrogen referring to protein. The outer shape of the crystals is geometrical with an up to hexagonal profile in cross sections. It ...
Spriet M.Positron emission tomography (PET) has established itself as a pertinent tool in equine musculoskeletal imaging in the last few years. With the ability to provide functional information regarding both bone and soft tissues, PET has found several clinical applications in horses. PET is currently used in horses as an enhanced bone scan, providing high-resolution 3-dimensional information, in particular for imaging of the racehorse fetlock. Combined with CT and MRI, PET is particularly pertinent in horses for the assessment of subchondral bone and enthesis. The development of a dedicated PET scan...
Ray CS, Baxter GM, McILWRAITH CW, Trotter GW, Powers BE, Park RD, Steyn PF.The objective of this study was to determine if damage to the articular cartilage alone or articular cartilage plus subchondral bone of the distal medial femoral condyle of young, exercised horses resulted in the formation of subchondral cystic lesions. Twelve Quarter Horses (age 1-2 years), free of clinical and radiographic signs of osteochondrosis and lameness were used. In 6 horses (Group 1), a 15 times 1 mm linear full thickness defect in the articular cartilage was made arthroscopically on the weightbearing surface of the distal aspect of the medial femoral condyle. In the other 6 horses ...
Noordwijk KJ, Chen L, Ruspi BD, Schurer S, Papa B, Fasanello DC, McDonough SP, Palmer SE, Porter IR, Basran PS, Donnelly E, Reesink HL.Proximal sesamoid bone (PSB) fracture is the leading cause of fatal musculoskeletal injury in Thoroughbred racehorses in Hong Kong and the US. Efforts are underway to investigate diagnostic modalities that could help identify racehorses at increased risk of fracture; however, features associated with PSB fracture risk are still poorly understood. The objectives of this study were to (1) investigate third metacarpal (MC3) and PSB density and mineral content using dual-energy X-ray absorptiometry (DXA), computed tomography (CT), Raman spectroscopy, and ash fraction measurements, and (2) investig...
O'Neill HD, Bladon BM.Current arthroscopic approaches to the caudal pouches of the lateral femorotibial joint are challenging and risk iatrogenic nerve and cartilage injury. Objective: Describe an alternative arthroscopic approach to the caudal pouches of the lateral femorotibial joint in the horse and report intra-articular abnormalities observed during diagnostic stifle arthroscopy of these pouches. Methods: Descriptive cadaver anatomical and clinical study. Methods: An approach to the caudal pouches of the lateral femorotibial joint was developed during clinical surgery using an arthroscopic portal in the poplit...
Gutiérrez-Crespo B, Kircher PR, Carrera I.The aim of this study was to describe the appearance of the ligamentous structures of the occipitoatlantoaxial (OAA) region in the normal horse by 3 tesla (3T) magnetic resonance imaging (MRI). The MRI images of the longitudinal odontoid ligament, tectorial membrane, dorsal and ventral atlantoaxial ligaments, dorsal atlantooccipital membrane with its reinforcing ligaments, and the lateral atlantooccipital ligaments of 10 horse cadavers were evaluated. All ligaments and membranes were identified in all planes, except for the lateral atlantooccipital ligament in the sagittal plane due to its cra...
Butcher MT, Bertram JE, Benzuidenhout AJ.The distal forelimb of the horse has a complex array of ligaments that play a critical role in determining function of the digit and are often associated with the initiation of foot pathologies. The collateral ligaments of the distal sesamoid bone (CLDS) play an important role in digit stabilization near the end of foot contact and there is also limited evidence to suggest that the CLDS stabilize the proximal interphalangeal joint (PIPJ) during weight bearing. By virtue of their anatomical attachments where the ligaments pass dorsal to the axis of rotation of the PIPJ, it is reasonable to assu...
De Auer , Ng JC, Seawright AA.The copper and zinc concentrations in the blood of stabled thoroughbred horses and in Australian Stock Horses mares at pasture, either late pregnant or lactating were determined by an atomic absorption spectroscopic method. The plasma concentration of the trace elements in these apparently normal horses were generally below the "normal" range. The plasma copper, caeruloplasmin copper, whole blood copper and plasma zinc concentrations in the stabled thoroughbreds were 0.76 +/- 0.19 micrograms/ml (n = 82), 0.56 +/- 0.14 micrograms/ml (n = 83), 0.75 +/- 0.18 micrograms/ml (n = 82) and 0.47 +/- 0....
Elgersma AE, Wijnberg ID, Sleutjens J, van der Kolk JH, van Weeren PR, Back W.Head and neck positions (HNP) in sport horses are under debate in the equine community, as they could interfere with equine welfare. HNPs have not been quantified objectively and no information is available on their head and neck loading. Objective: To quantify in vivo HNPs in sport horses and develop o a model to estimate loading on the cervical vertebrae in these positions. Methods: Videos were taken of 7 Warmbloods at walk on a straight line in 5 positions, representing all HNPs during Warmblood training and competition. Markers were glued at 5 anatomical landmarks. Two-dimensional angles a...
Story MR, Bramlage LR.Historically, there has been a consensus that conservative management of subchondral cystic lesions of the distal phalanx carries a poor prognosis. Surgical management has been advocated; however, there are no reports documenting its routine use and successful surgical treatment. Objective: To describe arthroscopically-guided curettage of distal phalangeal subchondral cystic lesions (SCLs) and report the qualitative and quantitative results in 11 affected horses age 16-33 months. Methods: Medical records of horses with previously treated lameness resulting from SCLs of the third phalanx were r...
Nam GH, Ahn K, Bae JH, Cho BW, Park KD, Lee HK, Yang YM, Kim TH, Seong HH, Han K, Kim HS.In the mitochondrial matrix, the OXCT1 gene catalyzes the reversible transfer of coenzyme A from succinyl-CoA to acetoacetate in a reaction related to energy production from ketone bodies. Here, horse OXCT1 gene containing coenzyme A transferase domain was identified in the transcriptome analysis of cDNAs derived from skeletal muscles. Horse OXCT1 gene consisted of 1761 [corrected] nucleotide sequences with an open reading frame of 1560 nucleotides encoding a protein of 520 putative amino acid residues.The number of non-synonymous substitutions was lower than the number of synonymous substitut...
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...
