Equine Injuries Research Articles

Anomalous Incidence of Fatal Musculoskeletal Injury in North American 2-Year-Old Thoroughbred Racehorses in the Year 2020.

Racehorse training and racing schedules in many parts of the United States and Canada were interrupted or otherwise reduced during the first three to six months of 2020. This was an indirect consequence of mitigations to prevent the spread of the pandemic virus COVID-19. Data from the Equine Injury Database, a census-level survey of all race starts made in the USA and Canada, were used to analyse the incidence of fatalities in 2009-2022 among three age cohorts of racehorses within each year. There was a statistically significant increase in the incidence of musculoskeletal fatalities among 2-year-old Thoroughbreds in 2020, compared to the period 2009-2019. In 2021 and 2022, the training schedules of 2-year-old horses returned to pre-2020 levels, as did the incidence of fatalities. The delayed start to training for 2-year-old horses was associated with an increase in risk of fatal musculoskeletal injury for those horses during 2020, but the risk for the same horses in 2021-when they were 3 years old-was not significantly different to the risk for 3-year-olds in any other year. The increased risk of fatal musculoskeletal injury in 2020 was only found among horses that were 2 years old in 2020-horses aged 3 years or more in 2020 were not at increased risk.

Human Injuries Associated with the Transport of Horses by Road.

There is an increased understanding of shared human-animal risk in terms of "one welfare", whereby when animals are at risk, so are people, so preventing injury to one species may also prevent injury to the other. Because transport-related injuries to horses are common, the authors considered this paradigm to study road equine transport-related injuries to humans in New Zealand. The aim was to determine their frequency and associated factors by distributing a survey to horse industry participants through industry organisations asking about their horse activities, road transport experiences, and any related self-injury. There were 112/1067 (10.5%) handlers injured while preparing (13/112), loading (39/112), traveling (6/112), or unloading (33/112). Of these, 40% had multiple injury types, and 33% had several body regions affected. Hand injuries were most common (46%), followed by the foot (25%), arm (17%), and head or face (15%). Median recovery time was 7 days. Injuries were associated with the responder's industry educational background, years of driving experience, and reporting a horse injured during road transport in the past two years. Wearing helmets and gloves, and adopting strategies designed to eliminate equine injuries associated with the road transport of horses to reduce the risk of injury to their handlers are recommended.

Fifteen risk factors associated with sudden death in Thoroughbred racehorses in North America (2009-2021).

To identify risk factors associated with race-related sudden death in Thoroughbred racehorses in the US and Canada. 4,198,073 race starts made by 284,387 Thoroughbred horses at 144 racetracks in the US and Canada between 2009 and 2021. Study data were extracted from the Equine Injury Database, which contains detailed records of 92.2% of all official race starts made in the US and Canada during the study period. Forty-nine potential risk factors were analyzed using univariable and multivariable logistic regression. Cases were defined as race starts that resulted in fatality within 3 days of racing, in which at least 1 of 5 codes relating to sudden death was recorded. Fatalities due to catastrophic musculoskeletal injury were omitted from the study cohort. 536 race starts resulted in sudden death, an incidence rate of 0.13/1,000 starts. Fifteen risk factors were significantly associated with sudden death, including horse age and sex, season and purse of race, race distance, and horses' recent history of injury and lay-up. Horses racing while on furosemide medication were at 62% increased odds of sudden death. Associations found between previous injury and sudden death suggests preexisting pathology could contribute in some cases. The association between furosemide and sudden death prompts further study to understand which biological processes could contribute to this result.

Use of Omics Data in Fracture Prediction; a Scoping and Systematic Review in Horses and Humans.

Simple SummaryDespite many recent advances in imaging and epidemiological data analysis, musculoskeletal injuries continue to be a welfare issue in racehorses. Omics studies describe the study of protein, genetic material (both DNA and RNA, including microRNAs—small non-coding ribonucleic acids) and metabolites that may provide insights into the pathophysiology of disease or opportunities to monitor response to treatment when measured in bodily fluids. As these fields of study are scientifically complex and highly specialised, it is timely to perform a review of the current literature to allow for the design of robust studies that allow for repeatable work. Systematic reviews have been introduced into the medical literature and are a methodological way of searching for relevant papers followed by critical review of the content and a detection of biases. The objectives of the current systematic review were to identify and critically appraise the literature pertaining to microRNA (miRNA) and their target genes that are correlated with stress fractures in racehorses and humans. The object was to define a panel of miRNAs and their target genes as potential biomarkers in either horses or human subjects. The online scientific databases were searched and a reviewed was performed according to preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. MicroRNA profiling studies in horses continue to emerge, but as of yet, no miRNA profile can reliably predict the occurrence of fractures. It is very important that future studies are well designed to mitigate the effects of variation in sample size, exercise and normalisation methods.Despite many recent advances in imaging and epidemiological data analysis, musculoskeletal injuries continue to be a welfare issue in racehorses. Peptide biomarker studies have failed to consistently predict bone injury. Molecular profiling studies provide an opportunity to study equine musculoskeletal disease. A systematic review of the literature was performed using preferred reporting items for systematic reviews and meta-analyses protocols (PRISMA-P) guidelines to assess the use of miRNA profiling studies in equine and human musculoskeletal injuries. Data were extracted from 40 papers between 2008 and 2020. Three miRNA studies profiling equine musculoskeletal disease were identified, none of which related to equine stress fractures. Eleven papers studied miRNA profiles in osteoporotic human patients with fractures, but differentially expressed miRNAs were not consistent between studies. MicroRNA target prediction programmes also produced conflicting results between studies. Exercise affected miRNA profiles in both horse and human studies (e.g., miR-21 was upregulated by endurance exercise and miR-125b was downregulated by exercise). MicroRNA profiling studies in horses continue to emerge, but as yet, no miRNA profile can reliably predict the occurrence of fractures. It is very important that future studies are well designed to mitigate the effects of variation in sample size, exercise and normalisation methods.

Effects of Racing Surface and Turn Radius on Fatal Limb Fractures in Thoroughbred Racehorses

North American Thoroughbred racing is conducted on three types of surfaces—dirt, turf, and synthetic. The tracks are oval, and races are run counterclockwise. The loading on right and left limbs is expected to differ as a function of turn radius, banking, surface, and gait asymmetry. Hind limbs and forelimbs also have different functions related to propulsion and turning, respectively. This study uses the Equine Injury Database for race starts from 1 January 2009 through 31 December 2014, to compare injury rates across participating North American racetracks. The data are limited to catastrophic injuries in which horses died or were euthanized due to a fracture within 72 h of the start of the race. Overall injury rates were lower on turf and synthetic surfaces and the pattern of limb injuries in left vs. right and fore vs. hind limbs were different. Regardless of surface, forelimbs were more likely to fracture. Dirt surfaces showed higher rates of forelimb injuries compared to other surfaces, hind limbs were more likely to experience a fatal fracture on turf than on dirt. The left fore and right hind limbs were more likely to experience a fatal fracture but only on dirt surfaces.

Effect of Pen Size on Stress Responses of Stall-Housed Horses Receiving One Hour of Daily Turnout

Group turnout provides important socializing opportunities for horses, particularly those that are primarily stalled. A high percentage of equine injuries occur during group turnout, which could partly be due to the physical constraints of fencing. To investigate appropriate paddock sizes for group turnouts, horses (n = 12) from a single herd were divided into groups of 4, stalled for 24 hours, and then turned out for 1 hour into one of three differently sized pens: 342, 263, and 184 m2 per horse. Groups rotated through pens across 3 days, receiving one treatment per day. Blood was sampled for cortisol concentrations at 08:00 hours each morning, and then at 15 and 60 minutes into the turn out sessions, and 60 minutes after return to individual stalls. Groups rotated through three turnout times: 09:00, 12:00, 14:00 hours. Counts of agonistic behaviors (chasing, contact biting, and kicking) and low-level threats (pinned ears, tail swishing, bite and kick threats) were recorded. When turned out in pens that provided 342 m2 per horse, horses exhibited reduced plasma cortisol concentrations by 15 minutes after turnout and at 1 hour after return to their stalls (P < .05). Horses in pens providing 184 m2 per horse exhibited greater agonistic (P < .001) and low-level threat (P < .01) behaviors than horses in larger pens. These data provide insight into appropriate pen sizes for horses from established herds. Providing at least 342 m2 per horse may reduce the chance of injury in horses accustomed to group turnout.

Cardiac troponins in diagnostics of equine myocardial injury

Cardiac troponins in diagnostics of equine myocardial injury

A Retrospective Survey of Factors Affecting the Risk of Incidents and Equine Injury During Non-Commercial Transportation by Road in the United Kingdom.

Simple SummaryThe transport of horses by road is necessary for several reasons, including competition and leisure, moving horses between yards and for breeding and veterinary purposes. In addition to the risks associated with road travel in general, the reaction of some horses to confinement in a transport vehicle may result in injury to the animal. An online survey was carried out to investigate the frequency of incidents during road transport and identify potential risk factors. Of the 2116 survey participants, 342 reported incident details. Over 50% of these incidents were attributed to the behaviour of the horse during transport, with most of these occurring during the first hour of the outward journey. The horse was injured in over 50% of the incidents, with transport vehicle malfunction being thought to be responsible for 68% of these injuries. Those transporting horses for competitive or professional purposes were more likely to have reported an incident than those transporting for leisure purposes. The findings of this survey highlight the need for better training and preparation of horses for transportation and to identify the risk factors associated with transport vehicles. The number of equines injured as a result of incidents during road transport is currently unknown in the United Kingdom. Although previous research has identified factors that affect an equine’s behavioural and physiological responses to transportation, their contribution to incident occurrence and injury risk is unclear. The aim of this study was to identify factors associated with incident occurrence and equine injury during transportation by road. An online survey was administered between 12 May 2017 and 21 July 2017 in the UK. The survey was open to those transporting equines non-commercially and comprised two sections. Questions relating to general transport behaviour were completed by all participants. Participants who had experienced an incident then provided details of these, including outcomes. Incidents were reported by 16.2% (342/2116) of participants, with details included for 399 incidents. Those participants who had a professional/competitive involvement with equines reported more incidents than those with a predominantly leisure involvement (p < 0.01). Equine behaviour was the attributed cause of 56% of incidents reported and most incidents occurred during the first hour of travel (65%). In over 50% of the incidents reported, the equine was injured, with those incidents attributed to transport vehicle malfunction being associated with the highest percentage of injury (68%). This study highlights the need for better preparation of the equine for transportation and to identify risk factors associated with transport vehicle type, design and operation.

Liver trauma in equestrian accidents. A case report

Background: Equestrian sports may carry a risk of liver injury. Horse kick injuries usually occur when rides are dismounted, most frequently when grooming without wearing protective equipment. Equine-associated liver injuries are not well studied due to the relative infrequency of these patients. Some of these patients needs surgery to repair liver injuries but most of them can be management with close observation. Methods: We present a case of hepatic trauma due to equine injury. Results: 21-year-old-female, abdominal pain after being kicked by a horse in the right side of the abdomen. On admission: tachycardia (120 bpm) and hipotension (90/40), diffused abdominal tenderness, haemoglobin level of 12 g/dl with elevation of liver transaminases. CT: laceration grade IV of the right liver (AAST scale). Laparotomy was performed. 2 litres of hemoperitoneum were evacuated and a resection of segment VI was carried. No more abdominal injuries were found. After surgery, haemoglobin levels were 9,2 g/dl after receiving 2 transfusions of concentrated red blood cells. The patient was discharged after 6 days, without complications. Conclusion: Liver injuries in equestrian accidents should be suspected and carefully managed. When haemodynamic instability appears, surgical intervention is mandatory for bleeding control. If there is no instability, conservative management could be taken. Radiological intervention such as embolization is an increasingly viable alternative in the non-operative management in stable patients.

The psychological responses of amateur riders to their horses’ injuries

Equestrian sport is considered a high-risk environment for equine injury. Due to the close bond between horse and rider, it could be theorised that riders may be impacted psychologically by their horses’ injuries, as seen in athletic pairs and with companion animal ownership. The extensive time commitment and responsibility of care within equestrian sport means that horse riders’ day-to-day life is impacted in a way not seen in other sporting or leisure environments, thus providing a unique opportunity to investigate the psychological responses of riders to their horse’s injury. The aims of this study were to investigate the psychological responses that amateur riders experienced when their horses were injured. 308 amateur horse riders (16 male and 292 female, median age 25-30 category) completed the Psychological Response to Sport Injury Inventory (19-item) (PRSII) and questions regarding demographics, investment in equestrian sport, the horse’s injury and the length of rehabilitation. Devastation was significantly affected by the weekly time investment of riders (H(3)=8.255, P=0.041) and the length of ownership prior to the injury (H(2)=7.690, P=0.021). ‘Devastation’, ‘feeling cheated’, ‘restlessness’ and ‘isolation’ were all significantly affected by the length of rehabilitation for the horse (H(7)=70.825, P=0.000, H(7)=37.799, P=0.000, H(7)=37.799, P=0.004, and H(7)=27.486, P=0.000, respectively). These findings suggest that amateur horse riders are at risk of psychological distress when their horse becomes injured. Whilst the industry has developed strategies to support owners following euthanasia which are already in place, psychological support following horse injury may be necessary to buffer psychological ‘devastation’ within amateur horse owners.

An estimation of US horse-owner/caregiver willingness-to-pay for daily use and infectious upper respiratory disease treatment options.

Equine injury and disease cause two types of costs for those financially responsible for treating and caring for the infected horse(s); direct costs of treating the horse and indirect cost of lost use of the horse for a period of time to the user of the horse (daily horse use). Indirect costs are more difficult to estimate but pose significant financial implications for equine-owners/caregivers. Additionally, there exists a gap in existing research regarding the valuation of infectious treatment options in horses. To estimate the value a US horse-owner/caregiver places on daily horse use and describe respondents' willingness-to-pay for various attributes of equine treatment options. Online questionnaire survey. An online questionnaire was provided to equine-owners and caretakers, and owner demographic, horse care and horse use information from respondents were requested. Additionally, respondents were presented with hypothetical disease treatment options with the following attributes: daily dosage, number of days of rest required, route of administration and out-of-pocket cost to the owner/caretaker through a choice experiment. Data were analysed using a rank-ordered logit analysis and willingness-to-pay estimates for daily use and treatment options were calculated. Results suggest that the average horse-owner with an uninsured and insured horse is willing to pay $12.07 (95% confidence interval: -$15.01, -$9.69) and $17.95 (95% confidence interval: -$25.30, -$11.20) per day to reduce lost use days required (due to need for rest) respectively. Respondents showed preferences for oral administration over treatments requiring i.m. injections. As this study employed an online survey it was subjected to self-selection bias and a sample size calculation was not performed. Veterinarians and pharmaceutical companies may use these results when promoting various treatment options to horse-owners/caregivers and in product development. Additionally, promotion efforts may be targeted towards equine-owners with higher daily use values (owners with insured horses).

Treatment of severe throracolumar fractures with posterior decompression, subtotal vertebrectomy, intervertebral fusion and internal fixation through unilateral pedicle

Objective To evaluate the effects of posterior decompression, subtotal vertebrectomy, intervertebral fusion and internal fixation through unilateral pedicle in the treatment of severe throracolumar fractures. Methods A retrospective study was conducted to evaluate the outcomes of 11 patients with severe throracolumar fracture who had been treated with posterior decompression, subtotal vertebrectomy, in-tervertebral fusion and internal fixation through unilateral pedicle at our department from March 2009 to March 2012. They were 10 males and one female, aged from 20 to 42 years (mean, 31.1 years). According to AO classification, there were 2 cases of type B1, 3 cases of type B2 and 6 cases of type C2. The Gaines scores for anterior column stability were more than 6 in all. All the patients had neurological disorders. The fracture reduction, fusion of bone grafting and recovery of neurological function were followed up. Results Their operation time ranged from 200 to 300 minutes, averaging 243.2 minutes; the amount of bleeding ranged from 800 to 1,600 mL, averaging 1,023.3 mL. No deterioration of neurological symptoms or no new neurological symptoms were observed postoperatively. Cerebrospinal fluid leakage was found in 3 patients who healed spontaneously following extubation, compressive dressing and elevation of the bed end. All the patients were followed up for 12 to 30 months (average, 18.3 months). A loosened screw cap was found in one patient after 6 months who had no discomfort and received no treatment. X-ray films showed satisfactory fracture reduction and fine bone grafting locations. No spinal canal stenosis was found by CT scans. It took 3 to 6 months (mean, 4.3 months) for the bone grafts to get fused. No height loss of the injured vertebrae was no found at the last follow-ups. No functional recovery was found in the patients with complete spinal cord injury whose Frankle grade remained A. The spinal function recovered from Frankel grade B to grade D in one patient with in-complete spinal injury. Of the 8 patients with medullary cone injury, 7 recovered Frankle grade E and one Frankle grade D. The symptoms were relieved in one patient with simple cauda equine injury. Conclusion Posterior decompression, subtotal vertebrectomy, intervertebral fusion and internal fixation through unilateral pedicle is an effective alternative for treatment of severe throracolumar fractures, because it can lead to satis-factory fracture reduction, thorough decompression of the spinal canal and good reconstruction of spinal sta-bility. Key words: Thoracic vertebrae; Lumber vertebrae; Fracture fixation, internal; Posterior; Subtotal vertebrectomy

Risk factors associated with fatal injuries in Thoroughbred racehorses competing in flat racing in the United States and Canada.

OBJECTIVE To identify risk factors associated with fatal injuries in Thoroughbred racehorses in the United States and Canada. DESIGN Retrospective study. ANIMALS 1,891,483 race starts by 154,527 Thoroughbred racehorses at 89 racetracks in the United States and Canada from 2009 to 2013. PROCEDURES Data were extracted from the Equine Injury Database, which contained information for 93.9% of all official flat racing events in the United States and Canada during the 5-year observation period. Forty-four possible risk factors were evaluated by univariate then multivariable logistic regression to identify those that were significantly associated with fatal injury (death or euthanasia of a horse within 3 days after sustaining an injury during a race). RESULTS 3,572 race starts ended with a fatal injury, resulting in a period incidence rate of 1.9 fatal injuries/1,000 race starts. Twenty-two risk factors were significantly associated with fatal injury. Risk of fatal injury was greater for stallions than for mares and geldings and increased as the number of previous nonfatal injuries and race withdrawals and level of competitiveness (eg, horse's winning percentage and race purse) of the horse or race increased. CONCLUSIONS AND CLINICAL RELEVANCE Results identified several risk factors associated with fatal injuries in Thoroughbred racehorses. This information can be used as a guideline for the identification of racehorses at high risk of sustaining a fatal injury and in the design and implementation of preventative measures to minimize the number of fatal injuries sustained by horses competing in flat racing in the United States and Canada.

Retrospective analysis of perioperative complications and risk factors of posterior lumbar interbody fusion for recurrent lumbar disc herniation

Objective To retrospectively analyze the perioperative complications of posterior lumbar interbody fusion (PLIF) for recurrent lumbar disc herniation and identify potential risk factors that correlate with those complications. Methods All of 71 patients with recurrent lumbar disc herniation were treated surgically with PLIF, discharged from our department between January 2008 and December 2014. Demographic and operation data were collected and perioperative complications were recorded. We analyzed whether the clinical factors (age, gender, BMI, co-morbidity, smoking, time of recurrence, blood loss, operation segment, operation time) were in correlation with perioperative complication by univariate analysis. Then we integrated the statistically significant indicators into Logistic regression equation to determine the related risk factors for complication. Results The study group consisted of 71 cases, including 42 males and 29 females. The age was 19 to 64 years old with an average of 50.6 years old, and the average BMI was 23.6 kg/m2. 26 cases had perioperative complications, while there were two or more complications in 5 patients, and no mortalities. Neurologic deterioration or neuropathic pain (10 cases, 14.1%) and dural tears (6 cases, 8.5%) were the most common intraoperaitive complications. The other complications included nerve root or cauda equine injury, deep or superficial wound infection, urinary tract infection, respiratory system complication, cardio-vascular complication and delirium. Univariate analysis suggested that age, gender, co-morbidity, smoking, time of recurrence, operation segment, operation time were not associated with perioperative complication. The multivariate Logistic regression analysis showed BMI and blood loss were closely related to perioperative complication. Conclusion Complications of posterior spinal fusion surgery for recurrent lumbar disc herniation are affected by many factors. The most common complications are transient neurologic deterioration or neuropathic pain and dural tears. BMI and blood loss are independent risk factors. Key words: Lumbar vertebrae; Intervertebral disc displacement; Recurrence; Intraoperative complications; Postoperative complications; Risk factors

Non-fatal injury occurrence in Southern California Thoroughbred racehorses 2009–2010

Private-practice racetrack veterinarians in southern California recorded non-fatal injuries meeting defined criteria in Thoroughbreds for 1 year. Injury incidence was 2.29 injury events per 100 horse-months, which was lower than other studies where trainer reported injury data were collected. Of 477 injuries recorded, 344 (72.1%) were acute and 133 (27.9%) were chronic. Fractures were common (47.6% of injuries), with stress fractures accounting for 14% of injuries. Superficial digital flexor tendonitis and suspensory ligament desmitis accounted for 15.3 and 11.5% of injuries, respectively. Agreement between non-fatal injuries recorded in the current study and those recorded via an existing regulatory system (Equine Injury Database) was poor, with neither system capturing all injuries. Non-fatal injuries occurred 17–29 times more often than fatal injuries. Non-fatal musculoskeletal injury remains an ongoing issue for Thoroughbred racehorses, and an accurate, comprehensive system for recording these injuries is needed.

Polo pony injuries: player-owner reported risk, perception, mitigation and risk factors.

Polo, one of the world's oldest sports, is unique in merging human skill and balance with animal agility and performance in a contact sport. These modern-day 'centaurs' offer medical, dental and veterinary scientists an unrivalled, if quirky, opportunity to collaborate. Collection of epidemiological data on injuries to UK polo riders and ponies is the first step. To measure the reported risk and risk factors for injuries to UK polo ponies, their perception and mitigation by player-owners. A retrospective cohort design and telephone interviews were used. Data on equine injuries, preseason training and risk perception were collected from a random sample of player-owners using a structured questionnaire. Injuries were defined as requiring veterinary treatment. Frequencies were represented as percentages and 95% confidence intervals (CIs). Risk factors for injuries were identified by univariable and multivariable analyses. The cumulative incidence of player-owner-reported injury was 10.6% (95% CI 8.4-12.7). Tendon injuries were most common (4.3%; 95% CI 2.9-5.7), followed by wounds and splints. The only risk factor was stabling all season (odds ratio 4.79; 95% CI 1.46-15.73). Tendon injuries were perceived as the major risk and hard ground the most important risk factor. Risk mitigation practices were bandaging before exercise (45.7%; 95% CI 34.8-56.5), checking tendons (84.0%; 95% CI 76.0-91.9), cold hosing (40.7%; 95% CI 30.0-51.4), bandaging (38.3%; 95% CI 27.7-48.9) and using clays and coolants after exercise (24.7%; 15.3-34.1). Cuts and wounds were considered most frequent by only 2.5% (95% CI 0.0-3.6) of players but were the second most common injury, accounting for 21.6% of veterinary treatments. Splints accounted for 12.5% of injuries. The risk of injury to polo ponies is similar to that in the general horse population; musculoskeletal injuries, particularly tendon injuries, are most common, followed by wounds and splints. The association between stabling and injury, risk factors for wounds and splints and efficacy of cooling tendons post exercise warrant further study.

Toepassingen van mesenchymale stamcellen bij het paard: huidige stand van zaken

Mesenchymale stamcellen (MSC) zijn adulte stamcellen met een beperkte differentiatiecapaciteit. Deze cellen kunnen therapeutisch aangewend worden om weefselregeneratie te stimuleren, vorming van littekenweefsel te voorkomen, immuunresponsen te moduleren en ontstekingsprocessen te reguleren. Binnen de diergeneeskunde worden MSC bij het paard voornamelijk gebruikt voor orthopedische toepassingen, hoewel ze ook een rol zouden kunnen spelen in de behandeling van verschillende niet-orthopedische letsels, zoals allerhande immuungemedieerde, ischemische, inflammatoire en neurologische aandoeningen. De efficiëntie van MSC-therapie kan beïnvloed worden door de gebruikte dosis en de manier en het tijdstip van toedienen. Tevens zijn er voor- en nadelen verbonden aan het gebruik van autologe ten opzichte van allogene MSC. Het gebruik van MSC bij paarden biedt immens veel mogelijkheden maar meer fundamenteel onderzoek en goed opgebouwde klinische trials zijn nodig zodat het potentieel van equine MSC ten volle kan geëvalueerd worden en equine MSC-gebaseerde therapieën kunnen geoptimaliseerd worden.

The Effect of Temperature on the Tangent Modulus of Granular Composite Sport Surfaces

A series of tests were conducted to determine the tangent modulus (vertical stiffness) values for a wax-coated granular composite material. This material is commonly used as the surface for Thoroughbred horse racetracks. The tangent modulus is important in the vertical loading of the surface by the hoof for a highly nonlinear material. Test temperatures span a range from 0 to 64°C and include the thermal transition regions of the wax coating obtained from differential scanning calorimetry tests. These temperatures also include the range of temperatures that are encountered during use. Creep tests were conducted to obtain steady-state strain conditions at loads ranging from 0.89 to 4.45 kN, the latter load approximating the weight of a Thoroughbred racehorse. Through-transmission ultrasonic waves were utilized to determine the tangent modulus values. The tangent moduli ranged from 74 to 573 MPa for the conditions tested. For all loads tested, a large decrease in modulus and decrease in material nonlinearity occurred as temperatures increased from 20 to 32°C. This temperature range matches the first thermal transition temperature for the wax coating of the track material. The results of this work provide a basis for racetrack maintenance decisions that can eliminate potentially adverse temperature effects and may reduce equine injuries.

The road to recovery

Katie Lawrence, Director of the College of Animal Physiotherapy and Secretary of the International Association of Animal Therapists (IAAT) discusses the role of physiotherapy in equine limb injuries

Equestrian Injuries Caused by Horse Kicks: First Results of a Prospective Multicenter Study

To analyze horse-related accidents caused by hoof kicks. Prospective study to evaluate hoof kick-related accidents. Multicenter study, including 9 trauma centers in Hamburg, Germany. Patients who were treated as the result of a hoof kick between January 1, 2010, and May 1, 2010, were included in the study. Horse and rider qualifications, riders' use of protective equipment, location and activity at time of accident, mechanism of injury, injuries sustained, and treatment required for these injuries. Twenty-four equestrians received hoof kicks. The average age was 22.6 years (range, 7-34 years). All accidents (100%) occurred while the equestrians were handing or grooming the horse. Two riders (8.3%) wore a helmet at time of accident. Sixteen riders (66.7%) suffered orbital, midface, or mandible fractures; 8 riders (33.3%) had injuries on other parts of the body. Hoof kick injuries account for a significant proportion of equine injuries and occur when riders are dismounted, most frequently when grooming without wearing protective equipment. Head and facial injuries occur most frequently and suggest that mandatory helmet and facial grill use should be considered during all horse-related activities.