Injury in horses encompasses a range of physical traumas that can affect various tissues and structures, including bones, muscles, tendons, and ligaments. These injuries can arise from numerous causes, such as accidents, overexertion, or improper handling. Common types of equine injuries include fractures, sprains, strains, and lacerations. The management and treatment of these injuries require an understanding of equine anatomy and biomechanics, as well as appropriate veterinary care. This page collects peer-reviewed research studies and scholarly articles that explore the causes, diagnosis, treatment, and prevention of injuries in horses, providing insights into their impact on equine health and performance.
Imai S, Sato R, Fujiwara R, Terui S, Kimura A, Ichijo T, Kasashima Y, Miyazaki T.A 15-year-old Thoroughbred gelding was presented for examination due to chronic corneal opacity in the right eye, which had been noted for several years. An ophthalmic evaluation revealed dense, irregular corneal opacity; an absence of the direct pupillary light reflex; and a positive dazzle reflex. Fluorescein staining was negative and cytology of a corneal conjunctival swab identified nucleated squamous epithelial cells, but no inflammatory cells. Slit-lamp examination failed to visualize intraocular structure, and the lesion was deemed to be chronic and irreversible. An obstacle-avoidance t...
Mazzucco L, Marcatili M, Withers J, Cantatore F.Superficial digital flexor tendinopathy is a common cause of forelimb lameness in Thoroughbred racehorses and sports horses; however, this condition is rarely observed in the hindlimb. A 16-year-old Irish sports horse gelding was presented with bilateral swelling in the plantar metatarsal region and severe bilateral hindlimb lameness visible at the walk. The lameness occurred after the cross-country phase of an eventing competition. The clinical suspicion of superficial digital flexor tendon (SDFT) injury was confirmed after ultrasonographic examination, which revealed an extensive core lesion...
Burns JJ, MacMillan KM.The Standardbred racing industry plays an important role in the North American economy and is expected to continue operating and growing. However, public perception is often unfavorable, with increasing concern about the health and welfare of Standardbred racehorses. Despite this, limited research has examined Standardbred well-being. To address this gap, a survey of equine trainers on Prince Edward Island (PEI) was conducted to evaluate key health and welfare issues during racing careers. Results showed that over one quarter of respondents had at least one horse displaying stereotypic behavio...
Markowitz JS.Equibase (EQB) race charts provide the official record of North American Thoroughbred races and often document catastrophic injury, euthanasia, or equine-ambulance transport. Because chart documentation and regulatory classification differ, fatalities occurring > 72 hours after a race fall outside international regulatory definitions applied by the Equine Injury Database (EID) and may not appear in EID aggregates. EQB charts confirm horse identity, race participation, finishing status, and last recorded start. Horseracing Wrongs (HRW), an advocacy group, publishes horse-level fatality data tha...
Hall NP, Sweeney DM, Holmströem M, Kim W, Wang Y, Donahue KD, Palmer SE, Lambert DH, Bayly WM.To determine whether targeted lesion-specific algorithms developed from data collected with accelerometer-based inertial measurement units worn by racing Thoroughbreds could retrospectively identify horses at high risk of incurring forelimb condylar or proximal sesamoid fractures. Unassigned: Fracture-specific algorithms were generated from July 2021 to December 2024 with accelerometer data from 42,623 races by 15,755 horses, including 54 races by 23 horses that subsequently suffered condylar fractures and 90 races by 31 horses that later sustained proximal sesamoid fractures. Fracture-specifi...
Gerow SL, Clegg SR, Cooke AS.In the UK, fireworks are common during several celebratory events throughout the year. Previous evidence has shown the adverse effects of fireworks on domestic companion animals. However, there has been little focus on equids. An online survey was developed to understand the impact of fireworks on horses and donkeys, how owners attempt to mitigate these impacts, and the owners' views on fireworks. A total of 1,234 horse owners and 232 donkey owners responded. The majority (77%) advocated tighter regulations surrounding the use of fireworks, including reduction in the maximum noise produced, an...
Copelin C, Merkies K.Equestrian sport's social license to operate has come under scrutiny due to concerns surrounding the well-being of ridden horses. Inappropriate equipment use, such as harsh bits or overtight nosebands, can negatively influence well-being by generating inescapable pressure or pain on the sensitive structures of the horse's head and limiting natural behaviours. Restrictive equipment may also be used to generate exaggerated, stressful and uncomfortable head and neck positions such as hyperflexion. Saddles must be properly fitted to both horse and rider to ensure appropriate distribution of kinema...
Dos Santos TS, Dillmann JB, Giovelli M, Elias GO, Lima RK, Cescon S, Stainki DR, Dos Santos RC, Corrêa C, Monteiro SG.This study reports the successful use of maggot therapy in four horses with traumatic wounds caused by wire fences, treated in veterinary clinics and under field conditions in southern Brazil. All lesions showed tissue necrosis, purulent discharge, and foul odor, indicating infection and delayed healing. Sterile Lucilia cuprina larvae (L1 stage) were applied directly to the wounds for 48 hours. Rapid improvement was observed, with marked reduction of necrotic tissue, exudate, and odor, and stimulation of granulation tissue in three cases. Complete wound closure occurred between 10 and 60 days ...
Choi Y, Rosanowski SM, Parkin TD.To identify risk factors associated with complete humerus fractures in Thoroughbreds in South Korea. Unassigned: A retrospective case-control design with multivariable logistic regression was used. This study included 131 Thoroughbreds diagnosed with complete humerus fractures following racetrack activity between 2009 and 2022 (inclusive). Additionally, 660 healthy Thoroughbreds (699 observations) with at least 1 racetrack activity during the same period were included as controls. Unassigned: A total of 8 variables were associated with the risk of complete humerus fractures. Notably, horses wi...
Pécresse B, Moiroud C, Hanne-Poujade S, Hatrisse C, De Azevedo E, Coudry V, Jacquet S, Audigié F, Chateau H.Locomotor disorders involving the spine are a major cause of impaired performance and early retirement in sport horses. Swimming is increasingly incorporated into rehabilitation protocols, but its effects on spinal biomechanics remain poorly understood. This prospective study evaluated changes in thoracolumbar mobility in sixteen sport horses diagnosed with cervical or thoracolumbar axial musculoskeletal lesions over a 12-week rehabilitation program comprising 4 weeks of land-based training followed by 8 weeks during which swimming sessions were incorporated three times per week. Weekly measur...
Repciuc CC, Oros NV, Mureșan ȘMC, Sevastre B, Joaquim JGF, Oana LI.Limb wounds in horses represent a significant therapeutic challenge due to poor vascularization, reduced skin elasticity, and high risk of complications such as exuberant granulation tissue. Conventional treatments sometimes fail to provide satisfactory healing outcomes, leading to prolonged recovery and increased costs. This study aimed to evaluate the efficacy of topical ozone therapy using the bagging method in promoting the epithelialization and contraction of chronic distal limb wounds in horses refractory to conventional management. Eight horses, aged 3-21 years, with chronic wounds aver...
Loder RT, Walker AL, Blakemore LC.IntroductionAmputations and avulsion injuries due to horse-associated activity are rare, yet they can result in significant impairment. The purpose of this study was to further investigate such injuries using a national emergency department database.MethodsThe US National Electronic Injury Surveillance System (NEISS) was used to identify horse-associated amputation and avulsion injuries occurring between 2000-2023. Demographic data of age, sex, and injury details were collected.ResultsThere were 34,091 emergency department visits for equine-associated injuries, with 120 (0.35%) due to amputati...
Weixler VHM, Aldana-Aguirre J, Zaulan O, Chin V, Guerguerian AM, Mertens L, Honjo O.We present 2 cases of traumatic ventricular septal defects (VSDs), both caused by horse kick injuries. Given this rare but critical condition, we decided to share our experiences and the lessons learned managing these cases. Methods: The first patient, a 12-year-old girl, was trampled by a horse, sustained a traumatic apical ventricular septal defect with pseudoaneurysm, was stabilized first, and underwent surgical closure 19 days after the injury. The second patient, a 9-year-old girl, was kicked by a horse in the chest; developed profound cardiogenic shock; and was found to have multiple lar...
Aßmann AD, Sànchez-Andrade JS, Argüelles D, Bischofberger AS.Diagnosing digital flexor tendon sheath (DFTS) pathologies, particularly manica flexoria (MF) tears, can be challenging with standard imaging modalities. Standing low-field MRI tenography (MRIt) may improve the detection rate of MF tears. This study aimed to compare ultrasonography, contrast radiography, pre-contrast MRI, and MRIt to detect naturally occurring MF lesions in horses undergoing tenoscopy. Ten horses with a positive DFTS block, which underwent contrast radiography, ultrasonography, MRI, MRIt, and tenoscopy were included. Two radiologists evaluated the images and recorded whether a...
Smith RKW, Schramme MC.Superficial digital flexor tendinopathy is one of the most common orthopedic soft tissue injuries in horses. The veterinary challenge for this condition is less related to identifying the presence of the injury (as it is usually readily evident clinically) but more related to improving the healing process so that the healed tendon is more like normal tendon in biology and function in order to reduce reinjury, which is the key adverse consequence of the injury. Diagnostic imaging has improved in recent years to aid with treatment choices and monitoring the healing process.
Durgam S.The mid-metacarpal SDFT, intrasynovial DDFT and suspensory ligament are frequently injured soft tissues in the equine athlete. The mid-metacarpal SDFT exhibits a hierarchical structure and encounters repetitive strains at its functional limit. The intrasynovial DDFT possesses fibrocartilage where opposing bony surfaces to facilitate resistance-free gliding and contains chondrocyte-like cells embedded in a proteoglycan-rich ECM. While suspensory ligament enthesis injuries are common, collagen and non-collagen ECM structure-function specializations at the bone-ligament interface are understudied...
Fletcher KA, Benedetti B, Limon G, Grist A, Padalino B, Hernández-Gil M, Gibson TJ.There has been limited research into the effectiveness of penetrating captive bolt (PCB) for stunning horses () at slaughter. This study observed 100 horses at a commercial abattoir in Mexico, stunned using pneumatic PCB. Animals were assessed at the time of stunning and immediately after for signs of effective/ineffective stunning and shot positioning, with macroscopic gross brain pathology conducted to determine brain trauma. Twenty-five percent (25/100) received more than one shot and 28% (28/100) displayed behavioural signs of ineffective stunning. Of these 28 animals, all had deviations o...
Legg KA, Gibson MJ, Gee EK, Rogers CW.Injury modelling based on changes in speed and stride characteristics of racehorses has become a primary industry focus for the Thoroughbred racing industry. However, speed and stride characteristics are strongly associated with track condition; therefore, reliable quantification of surface variables for use in future models is imperative. Objective: This study aimed to understand the interaction of objective turf track condition score (TCS) measurement with racing speed and injury in flat racing Thoroughbred horses. Methods: Retrospective time series analysis. Methods: Race-day data from 16 f...
Suomala H, Brotherus I, Hänninen L, Ternman E, Mykkänen AK.Very little is known about sleep disturbances in horses, although several management or animal-based factors may contribute to an increased risk of disturbances. Objective: To investigate factors related to rest and sleep behaviour of horses kept in stalls as perceived by Nordic horse owners or caretakers and their association with suspected sleep disturbances (SSD). Methods: Cross-sectional survey. Methods: The 40 question online international survey included a convenience sample of horse owners or caretakers with horses over 4 years old kept in the same individual stalls for at least the l...
Schild CO, Nyaoke A, Asin J, Henderson EE, Blea JA, Stover SM, Uzal FA.Radial fractures are relatively uncommon (0-1%) injuries in postmortem studies of racehorses, and few cases have been published. We describe here a series of 42 cases of radial fractures observed in California racehorses. Autopsy findings from all racehorses submitted for postmortem examination between 2006 July 1 and 2022 June 30 that had a recorded radial fracture were evaluated. We included 42 horses (30 Thoroughbreds, 12 Quarter Horses), most of which were 3-5-y-old. Catastrophic radial fracture was observed in 30 (71%) horses; in the remaining 12 (29%) horses, the fracture of the radius w...
Doherty O, Conway R, McGreevy P.Pressures applied to horses via nosebands are of growing concern. The current study applied noseband pressure to the head of a dead horse. Pressure sensors were placed on the left nasal bone to record pressures as the noseband was progressively tightened. Tightness increased as predicated by holes in the strap of the noseband (as supplied) through eight steps from two fingers' space, assessed using the standard International Society for Equitation Science Taper Gauge through to zero space. Sensors were also placed at the midline frontal plane and intra-orally at the level of the second premola...
Maloney B, Jung MS, Kearns G, Bowe C.Equestrian-related activities inherently involve the risk of serious injury. There are few reports of maxillofacial injury patterns and management arising from equestrian activities in the literature. Objective: To investigate maxillofacial fracture presentations at a tertiary trauma centre to identify injury profiles of patients who have sustained equine-based injuries over 5 years. Methods: This work involved a retrospective review of all trauma presentations to our unit over 5 years. The data collected included patient demographics, injury mechanisms and patterns, and management of fractu...
Stucki G, Valet S, Fuerst AE, Weisse B, Jackson MA.The aim of this study was to compare the strength (load at failure) and the number of cycles to failure of 3.5- and 4.0-mm cortical screw-bone constructs for repair of navicular bone fractures in horses.This was an in vitro biomechanical study that used a four-point bending apparatus to determine the load at failure of 3.5- and 4.0-mm cortical screw-bone constructs subjected to static and cyclic loading.In static testing, pairwise comparison of 4.0-mm cortical screw-bone constructs demonstrated significantly greater strength (mean increase: +16%, = 0.0135) compared with those in the 3.5-m...
McCarthy J, Cameron-Whytock HA, Bennet ED.Thoroughbred racing is a major industry, and in recent years, public concerns about equine safety have become more prominent, particularly in relation to on-track injuries and fatalities. This has challenged the industry's social licence to operate (SLO). Objective: To investigate and elucidate how UK and Irish racing stakeholders perceive risks to racehorses on race day and how those risks should be managed. Methods: Qualitative analysis of stakeholder perspectives using a constructionist approach. Methods: Twelve stakeholders from veterinary, communication and regulatory sectors within racin...
Cordonnier T, Germon V, Lemé C, Jouve JL, Launay F, Pesenti S.Despite benefits in children, sport practice has been reported with higher risk of fractures. Our objective was to report the characteristics of sport-related fractures in children and to compare them to fractures sustained in a domestic context. Our hypothesis was that sports-related fractures more frequently required surgical treatment, and could therefore be considered more severe METHODS: We conducted a retrospective cohort study including patients under 16 years old, diagnosed with a fracture at the emergency department, excluding skull and face fractures. Demographic data, context of inj...
Mellish M, Burns J, Elce Y, Stull JW.Donkeys (Equus asinus) in East Africa are recognised as working with poorly designed harnesses and carts. The donkey cart used in regions of Africa, specifically Meru County, Kenya, appears to place the cart's weight solely on the donkey's mid-cervical region. The ventral area of the neck is vulnerable to external pressure on the trachea, which is superficially located. Objective: To compare the presence and severity of endoscopic abnormalities in the upper airway and trachea of Meru County working cart donkeys compared to pack donkeys. To determine associations between endoscopic and physical...
Graham AE, Carslake HB, Malalana F.Evidence for optimal location of subpalpebral lavage (SPL) systems is lacking. Objective: To compare the rate and types of complications with SPL systems located in central upper- compared with medial lower-eyelid in hospitalised patients. Methods: Prospective, randomised treatment trial. Methods: Horses admitted for ophthalmic treatment using an SPL system from February 2015 to January 2024 were included if ocular pathology did not necessitate SPL system placement in a specific location. Coin toss was used to determine location. SPL systems were monitored at least daily, and complications wer...
Loder RT, Walker AL, Blakemore LC. Equestrian activities can result in spine injuries. Most studies are from single centers, and none use a national database. It was the purpose of this study to describe the demographics, injury mechanisms, and types of equestrian-associated spinal injuries using a US national ED database. The National Electronic Injury Surveillance System database was queried for equestrian-related spine injuries from 2000-2023. ED disposition was categorized as discharged or not discharged. Statistical analyses accounted for the weighted, stratified nature of the data to obtain national estimates. There we...
Godwin EE, Young NJ, Dudhia J, Beamish IC, Smith RK.Mesenchymal stem (progenitor; stromal) cell (MSC) therapy has gained popularity for the treatment of equine tendon injuries but without reports of long-term follow-up. Objective: To evaluate the safety and reinjury rate of racehorses after intralesional MSC injection in a large study of naturally occurring superficial digital flexor tendinopathy and to compare these data with those published for other treatments. Methods: Safety was assessed clinically, ultrasonographically, scintigraphically and histologically in a cohort of treated cases: 141 client-owned treated racehorses followed-up for a...
Smith RK, Werling NJ, Dakin SG, Alam R, Goodship AE, Dudhia J.Tendon injuries are a common age-related degenerative condition where current treatment strategies fail to restore functionality and normal quality of life. This disease also occurs naturally in horses, with many similarities to human tendinopathy making it an ideal large animal model for human disease. Regenerative approaches are increasingly used to improve outcome involving mesenchymal stem cells (MSCs), supported by clinical data where injection of autologous bone marrow derived MSCs (BM-MSCs) suspended in marrow supernatant into injured tendons has halved the re-injury rate in racehorses....
Schnabel LV, Lynch ME, van der Meulen MC, Yeager AE, Kornatowski MA, Nixon AJ.Tendinitis remains a catastrophic injury among athletes. Mesenchymal stem cells (MSCs) have recently been investigated for use in the treatment of tendinitis. Previous work has demonstrated the value of insulin-like growth factor-I (IGF-I) to stimulate cellular proliferation and tendon fiber deposition in the core lesion of tendinitis. This study examined the effects of MSCs, as well as IGF-I gene-enhanced MSCs (AdIGF-MSCs) on tendon healing in vivo. Collagenase-induced bilateral tendinitis lesions were created in equine flexor digitorum superficialis tendons (SDFT). Tendons were treated with ...
Thorpe CT, Streeter I, Pinchbeck GL, Goodship AE, Clegg PD, Birch HL.Little is known about the rate at which protein turnover occurs in living tendon and whether the rate differs between tendons with different physiological roles. In this study, we have quantified the racemization of aspartic acid to calculate the age of the collagenous and non-collagenous components of the high strain injury-prone superficial digital flexor tendon (SDFT) and low strain rarely injured common digital extensor tendon (CDET) in a group of horses with a wide age range. In addition, the turnover of collagen was assessed indirectly by measuring the levels of collagen degradation mark...
Lomas AJ, Ryan CN, Sorushanova A, Shologu N, Sideri AI, Tsioli V, Fthenakis GC, Tzora A, Skoufos I, Quinlan LR, O'Laighin G, Mullen AM, Kelly JL....Tendon injuries represent a significant clinical burden on healthcare systems worldwide. As the human population ages and the life expectancy increases, tendon injuries will become more prevalent, especially among young individuals with long life ahead of them. Advancements in engineering, chemistry and biology have made available an array of three-dimensional scaffold-based intervention strategies, natural or synthetic in origin. Further, functionalisation strategies, based on biophysical, biochemical and biological cues, offer control over cellular functions; localisation and sustained relea...
Nixon AJ, Dahlgren LA, Haupt JL, Yeager AE, Ward DL.To assess the potential of adipose-derived nucleated cell (ADNC) fractions to improve tendon repair in horses with collagenase-induced tendinitis. Methods: 8 horses. Methods: Collagenase was used to induce tendinitis in the superficial digital flexor tendon of 1 forelimb in each horse. Four horses were treated by injection of autogenous ADNC fractions, and 4 control horses were injected with PBS solution. Healing was compared by weekly ultrasonographic evaluation. Horses were euthanatized at 6 weeks. Gross and histologic evaluation of tendon structure, fiber alignment, and collagen typing were...
Ferris DJ, Frisbie DD, Kisiday JD, McIlwraith CW, Hague BA, Major MD, Schneider RK, Zubrod CJ, Kawcak CE, Goodrich LR.To report outcome of horses with femorotibial lesions (meniscal, cartilage or ligamentous) treated with surgery and intra-articular administration of autologous bone marrow derived mesenchymal stem cells (BMSCs). Methods: Prospective case series. Methods: Horses (n = 33). Methods: Inclusion criteria included horses that had lameness localized to the stifle by diagnostic anesthesia, exploratory stifle arthroscopy and subsequent intra-articular administration of autologous BMSCs. Case details and follow-up were gathered from medical records, owner, trainer or veterinarian. Outcome was defined as...
Thorpe CT, Clegg PD, Birch HL.Tendon injury is one of the most common causes of wastage in the performance horse; the majority of tendon injuries occur to the superficial digital flexor tendon (SDFT) whereas few occur to the common digital extensor tendon. This review outlines the epidemiology and aetiology of equine tendon injury, reviews the different functions of the tendons in the equine forelimb and suggests possible reasons for the high rate of failure of the SDFT. An understanding of the mechanisms leading to matrix degeneration and subsequent tendon gross failure is the key to developing appropriate treatment and p...
Dakin SG, Dudhia J, Smith RK.Injuries to the superficial digital flexor tendon (SDFT) are an important cause of morbidity and mortality in equine athletes, but the healing response is poorly understood. One important drive for the healing of connective tissues is the inflammatory cascade, but the role of inflammation in tendinopathy has been contentious in the literature. This article reviews the processes involved in the healing of tendon injuries in natural disease and experimental models. The importance of inflammatory processes known to be active in tendon disease is discussed with particular focus on recent findings ...
Dyson SJ.There is a lack of long-term follow-up data for outcome of medical treatment of superficial digital flexor (SDF) tendonitis. Objective: To determine whether intralesional injection of hyaluronan, beta aminoproprionitrile fumarate (BAPN) or polysulphated glycosaminoglycans (PSGAG) or systemic administration of PSGAG yielded better results than a controlled exercise programme alone in the management of SDF tendonitis, with a minimum follow-up period of 2 years after resumption of full work; and to determine whether reinjury rate was related to sports discipline and whether fibre alignment score ...
Sivaguru M, Durgam S, Ambekar R, Luedtke D, Fried G, Stewart A, Toussaint KC.Fourier transform-second harmonic generation (FT-SHG) imaging is used as a technique for evaluating collagenase-induced injury in horse tendons. The differences in collagen fiber organization between normal and injured tendon are quantified. Results indicate that the organization of collagen fibers is regularly oriented in normal tendons and randomly organized in injured tendons. This is further supported through the use of additional metrics, in particular, the number of dark (no/minimal signal) and isotropic (no preferred fiber orientation) regions in the images, and the ratio of forward-to-...
Thorpe CT, Godinho MSC, Riley GP, Birch HL, Clegg PD, Screen HRC.While the predominant function of all tendons is to transfer force from muscle to bone and position the limbs, some tendons additionally function as energy stores, reducing the cost of locomotion. Energy storing tendons experience extremely high strains and need to be able to recoil efficiently for maximum energy storage and return. In the equine forelimb, the energy storing superficial digital flexor tendon (SDFT) has much higher failure strains than the positional common digital extensor tendon (CDET). However, we have previously shown that this is not due to differences in the properties of...
Eddy AL, Van Hoogmoed LM, Snyder JR.Equine thermography has increased in popularity recently because of improvements in thermal cameras and advances in image-processing software. The basic principle of thermography involves the transformation of surface heat from an object into a pictorial representation. The colour gradients generated reflect differences in the emitted heat. Variations from normal can be used to detect lameness or regions of inflammation in horses. Units can be so sensitive that flexor tendon injuries can be detected before the horse develops clinical lameness. Thermography has been used to evaluate several dif...
Thorpe CT, Udeze CP, Birch HL, Clegg PD, Screen HR.Age-related tendinopathy is common in both humans and horses; the initiation and progression of which is similar between species. The majority of tendon injuries occur to high-strain energy storing tendons, such as the human Achilles tendon and equine superficial digital flexor (SDFT). By contrast, the low-strain positional human anterior tibialis tendon and equine common digital extensor (CDET) are rarely injured. It has previously been established that greater extension occurs at the fascicular interface in the SDFT than in the CDET; this may facilitate the large strains experienced during l...
Patterson-Kane JC, Becker DL, Rich T.The equine superficial digital flexor tendon (SDFT) is a frequently injured structure that is functionally and clinically equivalent to the human Achilles tendon (AT). Both act as critical energy-storage systems during high-speed locomotion and can accumulate exercise- and age-related microdamage that predisposes to rupture during normal activity. Significant advances in understanding of the biology and pathology of exercise-induced tendon injury have occurred through comparative studies of equine digital tendons with varying functions and injury susceptibilities. Due to the limitations of in-...
Dowling BA, Dart AJ, Hodgson DR, Smith RK.The superficial digital flexor tendon (SDFT) is an elastic structure that during maximal exercise appears to operate close to its functional limits. The biomechanical and biochemical responses to exercise, injury, and healing are still poorly understood but ongoing research is providing valuable new information which is addressed in this review. It appears that the SDFT matures early, after which time it has limited ability to adapt to stress and undergoes progressive degeneration. Focal hypocellularity, collagen fibril degeneration, selective fibril loading and alterations in the noncollageno...
Smith RK.Optimal management of tendon overuse injuries in equine and human athletes should avoid the formation of excessive scar tissue, regenerate normal tendon matrix, and reduce re-injury rates. We hypothesized that the implantation of marrow-derived stromal stem cells (BM-MSCs), in far greater numbers than are present normally within tendon tissue, would synthesize a matrix more closely resembling tendon matrix than scar tissue, and hence increase the capacity to return to performance successfully. This article reviews the technique used clinically in the horse and the current outcome data for hors...
Guest DJ, Smith MR, Allen WR.Injury to the superficial digital flexor tendon (SDFT) is common in racing and sport horses and poor tendon regeneration leads to high reinjury rates. Autologous mesenchymal stromal cells (MSCs) are being used clinically to improve tendon regeneration but they have some practical limitations. Embryonic stem cells (ESCs) may overcome these limitations but their fate following injection into the damaged SDFT is unknown. Objective: To inject MSCs and ESCs into distinct areas of damage in the SDFT and monitor their survival over a 3 month period. Methods: MSCs and ESCs expressing different reporte...
Rossdale PD, Hopes R, Digby NJ, offord K.An epidemiological study of wastage among racehorses was conducted in 1982 and 1983 among six stables, five of which were in Newmarket. The basis of the survey was the inability of horses to take part in cantering exercise as a result of injury or disease. The greatest number of days lost to training was caused by lameness (67.6 per cent) and respiratory problems (20.5 per cent). Conditions of the foot (19 pe cent), muscle (18 per cent), carpus (14 per cent), fetlock joints (14 per cent), tendons (10 per cent) and sore shins (9 per cent) were the major reasons for training days being lost in 1...
Murray RC, Walters JM, Snart H, Dyson SJ, Parkin TD.The aim of this study was to describe the prevalence of illness and lameness at different anatomical sites in registered United Kingdom dressage horses and to identify risk factors for lameness. A questionnaire was sent to all 11,363 registered members of British Dressage in 2005, with one questionnaire assigned per horse. Four multivariable logistic regression models were developed for each section of the questionnaire. A final mixed effects logistic regression model was developed which combined the results from all prior models. Owners reported that 33% of horses had been lame at some time d...
Smith RK, Birch HL, Goodman S, Heinegård D, Goodship AE.Strain-induced tendinopathy is a common injury in both human and equine athletes, with increasing incidence associated with greater involvement in sport and an increasingly aged population. This paper reviews our studies on the abundant non-collagenous protein, cartilage oligomeric matrix protein (COMP), in equine tendons. Its variation between tendon type and site, age and exercise has provided an insight into how age and exercise influence tendon growth and maturation. Tendons can be broadly divided into two types, reflecting their different matrix composition and function: the energy-storin...
Peffers MJ, Thorpe CT, Collins JA, Eong R, Wei TK, Screen HR, Clegg PD.Energy storing tendons, such as the human Achilles and equine superficial digital flexor tendon (SDFT), are highly prone to injury, the incidence of which increases with aging. The cellular and molecular mechanisms that result in increased injury in aged tendons are not well established but are thought to result in altered matrix turnover. However, little attempt has been made to fully characterize the tendon proteome nor determine how the abundance of specific tendon proteins changes with aging and/or injury. The aim of this study was, therefore, to assess the protein profile of normal SDFTs ...
Carvalho Ade M, Badial PR, Álvarez LE, Yamada AL, Borges AS, Deffune E, Hussni CA, Garcia Alves AL.Tendon injury is a major cause of lameness and decreased performance in athletic equines. Various therapies for tendonitis have been described; however, none of these therapies results in complete tissue regeneration, and the injury recurrence rate is high even after long recovery periods involving rest and physiotherapy. Methods: A lesion was induced with collagenase gel in the superficial digital flexor tendon in the center portion of the metacarpal region of eight equines of mixed breed. After two weeks, the lesions of the animals in the treated and control groups were treated through the i...
Richardson LE, Dudhia J, Clegg PD, Smith R.Stem cells have evoked considerable excitement in the animal-owning public because of the promise that stem cell technology could deliver tissue regeneration for injuries for which natural repair mechanisms do not deliver functional recovery and for which current therapeutic strategies have minimal effectiveness. This review focuses on the current use of stem cells within veterinary medicine, whose practitioners have used mesenchymal stem cells (MSCs), recovered from either bone marrow or adipose tissue, in clinical cases primarily to treat strain-induced tendon injury in the horse. The backgr...
Hitchens PL, Morrice-West AV, Stevenson MA, Whitton RC.Studies of racehorse injury or fatality in various countries have identified common, and in some cases conflicting, risk factors. We conducted a systematic search of the relevant literature published from 1990 to 2017. Peer-reviewed articles were included if they reported the incidence of fatal or catastrophic musculoskeletal injury (CMI) in Thoroughbred flat races (n=21) or risk factors for CMI (n=65). Pooled effect sizes were estimated using the random-effects DerSimonian-Laird model. The pooled incidence of CMI was 1.17 (95% confidence interval 0.90, 1.44) per 1000 race starts. Almost 300 f...
Ball CG, Ball JE, Kirkpatrick AW, Mulloy RH.Horseback riding is more dangerous than motorcycle riding, skiing, football, and rugby. The purpose of this study was to identify the incidence and injury patterns, as well as risk factors associated with severe equestrian trauma. Methods: All patients with major equestrian injuries (injury severity score > or = 12) admitted between 1995 and 2005 were reviewed. A 46-question survey outlining potential rider, animal, and environmental risk factors was administered. Results: Among 7941 trauma patients, 151 (2%) were injured on horseback (mean injury severity score, 20; mortality rate, 7%). In...
Kasashima Y, Takahashi T, Smith RK, Goodship AE, Kuwano A, Ueno T, Hirano S.Overstrain injuries to the superficial digital flexor tendon (SDFT) and suspensory ligament (SI) are among the most common musculoskeletal injuries which contribute to the considerable wastage of racing Thoroughbreds. Many epidemiological studies have demonstrated the prevalence of and risk factors for tendon injury when racing but have not included those injuries sustained during training. However, since tendon injury during training is seen commonly in clinical practice, it is appropriate to determine the overall prevalence of tendon injury sustained during both training and racing. Objectiv...
Bosch G, Moleman M, Barneveld A, van Weeren PR, van Schie HT.The repair process of tendon injuries, which are common in both human and equine athletes, is slow and the quality of the repair tissue is often inferior to the original tendon tissue, which frequently leads to re-injury. The relatively poor vascularization of tendons is considered to be one of the reasons for their limited healing potential. Recently, platelet-rich plasma (PRP), an autologous concentrate of platelets, rich in growth factors, has been shown to enhance the repair process of injured tendons. This effect has been ascribed to the high levels of growth factors in PRP, several of wh...
Jeffcott LB.The survey comprised 443 horses, referred to the clinical department of the Equine Research Station, with a history of a thoracolumbar (TL) complaint. A wide range of lesions were capable of producing back problems and more than one condition or site of injury was found in 75 animals (17 per cent). There were 103 horses (19.7 per cent) with no evidence of damage to the TL spine or its associated structures. In 66 of these cases, clinical signs were attributed to a variety of hindlimb lamenesses and, in 37, no specific diagnosis could be made. Soft tissue injury was diagnosed in 203 cases (38.8...
Watts AE, Yeager AE, Kopyov OV, Nixon AJ.Tendon injury is a common problem in athletes, with poor tissue regeneration and a high rate of re-injury. Stem cell therapy is an attractive treatment modality as it may induce tissue regeneration rather than tissue repair. Currently, there are no reports on the use of pluripotent cells in a large animal tendon model in vivo. We report the use of intra-lesional injection of male, fetal derived embryonic-like stem cells (fdESC) that express Oct-4, Nanog, SSEA4, Tra 1-60, Tra 1-81 and telomerase. Methods: Tendon injury was induced using a collagenase gel-physical defect model in the mid-metacar...
