Lameness in All-Around and Reining Horses
Lameness in All-Around and Reining Horses
By Katie Navarra with Tara Matsler
Your horse feels a little off, but you’re not certain where the discomfort is coming from. (Wouldn’t it be nice if horses could talk?) So you take your horse to the veterinarian to find out where he hurts. The good news is some research within the past few years has made it easier for veterinarians to know where to start.
How and Why the Study Came to Be
Dr. Sherry A. Johnson of Equine Sports Medicine LLC combed through 10 years of data to learn more about lameness at American Quarter Horse shows.
“Ultimately, if we as sports medicine veterinarians can understand the intricacies of what these equine athletes are expected to do and where injuries develop as a result, we will be more effective at diagnosing and treating each case,” she explains. “That involves really digging in and figuring out patterns of lameness for these western horses.”
Although musculoskeletal injury rates have been quantified in many disciplines, such as racing and steeple chasing, the data was lacking for the western performance athlete. Until now.
Dr. Johnson’s research continued the work of Dr. Josh Donnell, an associate at Equine Sports Medicine. Dr. Donnell used the unique caseload of ESM’s “vet truck” to investigate the most common regions of pain in western performance horses based on lameness examination results.
ESM is a mobile equine practice based in Pilot Point, Texas, known by horsemen as “the vet truck.” ESM veterinarians often serve as the official show veterinarians at many of AQHA’s nationally sanctioned shows.
Dr. Johnson wanted to provide insight into discipline-specific sources of lameness pain that might help inspire further study of diagnostic methods of injury-prevention strategies.
Lameness by the Numbers
When Dr. Johnson was looking at her stack of lameness examination results, she categorized each case as a horse that was competing in reining or all-around western events.
“We knew about 73 percent of the horses’ disciplines, and it made sense to just broadly characterize (the horses) as reiners or all-arounders,” she says. “As we get more data, we may even be able to eventually consider more specifically each AQHA discipline, such as western riders vs. the hunt-seat horses, for example.”
To be included in the study, horses had to have undergone a complete lameness examination where at least 70 percent of their initial lameness was localized with diagnostic blocking.
A total of 2,677 lameness exams on 2,521 horses were eligible for inclusion in the study.
Some horses were evaluated more than once for separate lameness issues.
The data showed the average age of the horse n the study was 11.5 years.
“Our industry should be proud of the fact that Quarter Horses are routinely competing into their teens and later,” she says. “To date, this is one of the largest data sets regarding diagnostic blocking patterns in western performance horses.”
What Is a Diagnostic Nerve Block?
Diagnostic nerve blocks are designed to isolate the anatomic region of lameness.
The process is started by desensitizing nerves of the lower limb with a local anesthetic near specific nerves, reperforming the lameness exam, then working up the limb until the veterinarians feel confident they know the affection region.
Top Regions of Lameness for Western Performance Horses
Based on the diagnostic blocking data, Dr. Johnson’s study identified the top three regions of lameness for western performance horses:
The lower foot region, also called the “distal forelimb,” was the top cause of lameness across all disciplines.
Tarsus (hock region).
“We know from this study that the foot region in western performance horses can be expected to cause lameness about 40 percent of the time, followed by the hock and suspensory region 16 percent of time, and the stifle 9 percent of the time,” she says.
While it was outside the scope of the study to include the exact diagnosis, sources of foot-associated lameness in the equine all-around injury included:
Pain from the navicular region.
Soft-tissue injuries like deep flexor tendon tearing.
Coffin joint collateral ligament injury.
When the exams from the all-around western performance horses were considered separately from the reiners, both groups experienced lameness in the same regions of the body, but at different rates of occurrence.
Top Regions of Lameness in All-Around Horses
(Horses that compete in horsemanship, western pleasure, western riding and English flat classes)
Lower foot region.
For example, all-around horses that compete in horsemanship, western pleasure, western riding and English flat classes most often exhibited lameness in the foot, followed by the stifle and then the hock.
Top Regions of Lameness in Reining Horses
Lower foot region.
When the cases were assessed by type of lameness they presented with – for example, single fore limb vs. single hind limb – the reiners most commonly presented with a single fore limb lamness, or lameness in one front limb.
“It was really interesting to see that reiners most commonly presented with a fore limb lameness considering the amount of hind-end engagement they typically use,” Dr. Johnson says. “Western performance horses certainly use their hind ends well, which reflected in their most common lameness, which was that of a single hind limb.”
She hopes that in future studies she can dive into why and how these patterns were observed.
“No one has ever quantified the percentage of time certain lamenesses would be present by western discipline,” she says. “Looking to the future, we want to look at these associations from a statistical point of view to help determine the relevance of these observed patterns. Knowing the anatomic source of pain helps us as veterinarians be better at diagnosing injury and developing prevention strategies.”
Finding the source of lameness with nerve blocks remains challenging, but the continued assessment of response to diagnostic analgesia may help characterize discipline-specific injuries. Knowing where to look first can support a streamlined approach that makes diagnosis faster and treatment more effective.
The Veterinarian Behind the Study
Riding and showing western performance horses as a youth motivated Dr. Sherry Johnson to seek a professional career diagnosing and treating lameness in the equine athlete. After graduating from the Iowa State University College of Veterinary Medicine in 2012, she completed an internship with Equine Medical Center in Ocala, Florida. After a year of advanced diagnostic imaging training with Colorado State University, she transitioned into the combined residency program with Equine Sports Medicine in Pilot Point, Texas. Her collaborative research under the senior veterinarians of CSU and ESM is focused on patterns of tendon healing and rehabilitation modalities related to tendon healing.