A fresh look at where, how, and why injuries happen in todays various equine sportsSoft-tissue injuries, including tendinitis and desmitis (ligament inflammation) are some of the most common career-ending injuries seen in horses. | iStock photoFor some equine athletes a torn suspensory ligament or degenerating pair of hocks marks the premature end of a competitive career. The musculoskeletal injuries we commonly see in different types of horses arent entirely randomthey often reflect the unique physical demands of each discipline. Looking at the current research and speaking with veterinary specialists, heres what we know so far about the predisposition of horses to discipline-specific sports injuries.The No. 1 Reason for Premature Retirement in Sport HorsesKara Brown, VMD, assistant professor of equine sports medicine and rehabilitation at the University of Pennsylvanias New Bolton Center, in Kennett Square, starts by acknowledging musculoskeletal disease as the single most common cause of premature retirement in equine athletes. Osteoarthritis, tendinitis, and desmitis (ligament inflammation) top her list of the most common career-ending injuries. Thats problematic because the inherent poor healing characteristics of cartilage, tendon, and ligaments make these types of injuries difficult to treat and prone to reinjury, she explains. That being said, advances in the management of these disease processes are certainly giving us more opportunities to intervene prior to the need for retirement.How Discipline Affects Equine Injury RiskMuch like tennis players develop the aptly named tennis elbow and long-distance runners often suffer from plantar fasciitis, equine athletes most common injuries closely link to their discipline. Discipline often reflects breedfor example, Quarter Horses in Western events, Warmbloods in dressage and show jumping, and Thoroughbreds or Standardbreds in racing. As a result veterinarians often see specific injuries correlate with specific breeds, pedigrees, conformation, and other related factors beyond the discipline itself.There are certainly many injuries that are overrepresented in certain disciplines and populations of horses, says Kim MacKinnon, DVM, CVA (Eq), an associate veterinarian at Avon Animal Hospital, in Windsor, Nova Scotia, Canada, with primary clinical interests in equine lameness and sports medicine. Different biomechanical forces are at play on a reining horse performing a sliding stop, for example, than a show jumper jumping a 1.45-meter course, or in a three-day eventer competing in consecutive dressage, cross-country, and show jumping phases of the event. We are asking these horses to use their bodies differently based on the maneuver, exercise, or obstacle. There are sport-specific biomechanical patterns that we are able to appreciate, which correspond to repeated loading of specific structures according to discipline.In any discipline Brown cautions equestrians against overusing certain movements and neglecting variety in training. With respect to management and training practices across disciplines, we find that horses that perform repetitive activities without diversity or variability in movement appear to be at higher risk for musculoskeletal injury, she says.Cross-training the horse allows multiple joints and muscles to share cumulative orthopedic stress. | Adobe stockBrianne Henderson, BVMS, MRCVS, of Ferguson Equine Veterinary Services, in Ontario, Canada, says varying training modalitiessuch as hillwork, trail riding, or swimmingallow joints and muscle groups to share cumulative orthopedic stress, reducing focal overload on vulnerable areas including hocks or suspensory ligaments.That being said, to some extent, the types of movements and activities required for performance cannot be altered, and its very important that the horses musculoskeletal tissues are gradually prepared for the stresses they undergo during competition, and also that the athletes are cardiovascularly prepared from a fitness perspective, Brown explains.Performance Level, Fitness, and Age Matter, TooDiscipline tells part of the story, but the level and intensity of competition add another dimension to injury risk. There appears to be a further subdivision between discipline and level of performance in terms of what injuries we are seeing, MacKinnon says. Age also plays a role in the injury patterns we see, as repetitive injuries and degenerative (joint) disease catch up with the horse as they undergo more wear and tear on soft tissue and osseous structures as they age and continue to perform.Researchers on a retrospective analysis of more than 1,000 horses and ponies undergoing orthopedic evaluation found elite competitors in eventing, show jumping, and dressage were far more likely to suffer injuries to specific structures compared to nonelite or general-purpose horses.1 Fitness level matters as much as performance level, it appears. In a different study of elite Thoroughbred eventers, horses labeled as good performers based on VLA4 (velocity at 4 millimoles/liter of blood lactatean exercise physiology marker used to assess aerobic vs. anaerobic capacity) and recovery heart rate had zero injuries, while average performers sustained injuries 50% of the time (P=0.05).11 Additionally, horses that remained sound had significantly lower peak heart rates during conditioning (186 beats per minute) than horses that sustained injury (201 bpm).Most Effective DiagnosticsWith todays diagnostic imaging tools, veterinarians can detect and treat injuries in sport horses before they progress to performance-inhibiting lameness. We are fortunate to have a diverse array of advanced imaging modalities, which are becoming more readily available and accessible in addition to what ambulatory veterinarians have in their trucks on a daily basis, MacKinnon says. The portability and ease of use of digital radiograph (X ray) units and ultrasound machines have elevated our point-of-care diagnostics in the past 1520 years and are now the standard of care. Advanced imaging modalities, such as positron emission tomography (PET) scans, computed tomography (CT) scans, high- and low-field MRI, and nuclear scintigraphy (bone scan) are also now all routinely used to diagnose injuries, prognosticate injuries, and develop treatment/rehabilitation plans tailored to the patient and specific injury.She says she considers the use of PET scans in clinical practice an exciting diagnostic tool. We are continuing to learn more about it in terms of what it can tell us about bone and soft tissue injury, both by itself and in conjunction with other imaging modalities, such as MRI, CT, and nuclear scintigraphy. PET has shown exciting promise to provide functional information about the activity of an injury, elucidating injury prior to appreciating structural change, determining the stage of healing of injuries, and in early detection of injuries prior to other modalities in some cases.Most Effective TreatmentsThe past few decades have brought major advances not only in diagnostic approaches but also in options for treating injured equine athletes. Experts agree the single most influential advancement in the treatment of equine musculoskeletal injuries remains regenerative medicinenotably orthobiologics, which use the healing properties of the horses own cellular components (from blood or stem cells) without the adverse effects of corticosteroids.RELATED CONTENT: Equine Innovators Podcast: Improving Joint Health in Horses With OrthobiologicsBrown says regenerative therapies play a critical role in extending the athletic careers of sport horses, particularly in the case of managing osteoarthritis and soft tissue injuries such as tendinitis and desmitis. For many years management of osteoarthritis was restricted to symptom-modifying treatments like joint injections with corticosteroids and systemic anti-inflammatories. While these can be very effective, from the perspective of long-term management of a performance horse, there are some downsidesthe repeated use of corticosteroids in the joint can be damaging to the cartilage, she says.Additionally, in older horses, the combination of endocrine disease such as pituitary pars intermedia dysfunction (PPID, formerly known as equine Cushings disease) and corticosteroid administration can increase the risk of adverse events, including laminitis, Brown explains. As for systemic anti-inflammatories, their use is often regulated during competition, and long-term administration can have adverse effects on both the gastrointestinal system and kidneys.She suggests regenerative medicine as a viable alternative for delivering targeted anti-inflammatory therapy to the joint without the potential adverse effects associated with corticosteroid treatments. Not only that, but there is now good data supporting the use of regenerative medicine therapies like platelet-rich plasma (PRP), autologous protein solution (APS), and stem cells, to improve the quality of healing soft tissues and decrease reinjury rate, explains Brown. From the perspective of soft tissue injury, optimizing the quality of healing is essential for reducing reinjury, which is a very common problem for tendon and ligament injuries.Take-Home MessageAdvanced imaging and regenerative therapies give equine veterinarians unprecedented ability to detect, treat, and manage musculoskeletal injuries. Identifying injured horses early remains a top priority. By understanding how and why injuries happen in different horse sports and applying that knowledge to reduce their occurrence through strategic conditioning, cross-training, and early intervention, we can improve outcomes and extend the careers of our equine athletes.References1. Murray RC, Dyson SJ, Tranquille C, Adams V. Association of type of sport and performance level with anatomical site of orthopaedic injury diagnosis. Equine Vet J. 2010;38(S36):411416.2. Rogers CW, Bolwell CF, Gee EK. Proactive management of the equine athlete. Animals. 2012;2(4): 640655.3. Singer ER, Barnes J, Saxby F, Murray JK. Injuries in the event horse:training versus competition. Vet J. 2008;175(1):7681.4. Johnson SA, Donnell JR, Donnell AD, Frisbie DD. Retrospective analysis of lameness localisation in Western performance horses: A ten-year review. Equine Vet J. 2021;53(6):11501158.5. Holbrook TC, Schoonover MJ. Veterinary Aspects of Conditioning, Training, and Competing Western Performance Horses. Equine Sports Medicine and Surgery (Third Edition). 2024;12721287.6. Wilsher S, Allen JL, Wood N. Factors associated with failure of Thoroughbred horses to train and race. Equine Vet J. 2010;38(20):113118.7. Parkin T, Lam K, Riggs C, Morgan K. Risk factors for tendon injuries that result in retirement from racing at the Hong Kong Jockey Club. Management of Lameness Causes in Sport Horses. Leiden, The Netherlands: Wageningen Academic, 2006.8. Shrestha K, Gilkerson JR, Stevenson MA, Flash ML. Drivers of exit and outcomes for Thoroughbred racehorses participating in the 20172018 Australian racing season. PLOS ONE. 2021;16(9):e0257581.9. Sousa NR, de Luna SPL, Pizzigatti D, Martins MTA, Possebon FS, Aguiar ACS. Relation between type and location of orthopedic injuries and physical activity in horses. Cinc Rural. 2017;47(2).10. Wright I, Minshall G, Young N, Riggs C. Fractures in Thoroughbred racing and the potential for pre-race identification of horses at risk. Equine Vet J. 2024;56(3):424436.11. Munsters C, van den Broek J, Welling E, et al. A prospective study on a cohort of horses and ponies selected for participation in the European Eventing Championship: reasons for withdrawal and predictive value of fitness tests. BMC Vet Res. 2013;9:182.This article is from the Research Roundup 2025 issue ofThe Horse: Your Guide to Equine Health Care. We at The Horse work to provide you with the latest and most reliable news and information on equine health, care, management, and welfare through our magazine and TheHorse.com. Your subscription helps The Horse continue to offer this vital resource to horse owners of all breeds, disciplines, and experience levels. To access current issues included in your subscription, please sign in to theAppleorGoogleapps ORclick herefor the desktop version.