Tuesday, March 17, 2015

The Hows and Whys of Lameness Exams

By Melinda Freckleton, DVM

When searching for the cause of lameness in a horse, a veterinarian follows a methodical lameness exam protocol. Knowing a bit about how that exam is conducted is important to understanding the ultimate lameness diagnosis and being an active partner in making your horse sound once again. In this article from EQUUS Magazine available as a printable download to keep at the barn for reference equine veterinarian Melinda Freckleton, DVM, explains her lameness exam protocol and discusses some of the questions and challenges owners will face as they tackle their horse's lameness issues.

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When I arrive on a farm to investigate a lameness case, I often wish I had a Star Trek-like scanner that I could wave over a horse to get a readout showing the exact location of the problem. Of course, diagnostic technology hasn’t advanced quite that far. But over the past two decades, examination protocols have advanced enough to take much of the guesswork out of diagnosing lameness.

So I don’t have a magic scanner, but I do have a logical progression of tests designed to reveal where lameness originates and, in many cases, what is causing it. All veterinarians learn the basic lameness exam format in veterinary school, and we then customize that process over time based on our own experiences and preferences.

To my clients, I’m sure it sometimes looks like I am just randomly picking legs to prod or jogging a horse back and forth while I think of something else to do. But each exam follows a specific process developed to increase the chance of revealing useful information.

Your veterinarian, no doubt, has his or her own specific approach to lameness examinations. But by showing you how I conduct mine, I hope to help you become a better partner in determining where your horse is hurting and what can be done about it.

WHEN IT’S EASY TO SEE

The easiest lameness exams, from a diagnostic standpoint, are those that involve a dramatic limp or even a hoof held off the ground. In these cases, even a non-horsy spouse can pick out which leg hurts---the horse couldn’t make it any clearer.

I generally will not ask a horse in this shape to walk, even a single step. Making him move will not only cause unnecessary discomfort, it could make a minor problem much worse---a hairline fracture can become a full break, for example. Instead, I’ll have the horse stand still as I look the leg over and run my hand over the tendons and joints.

A horse who is so obviously lame may have a massive cut, broken bone or damage to a vital structure. If I find anything like that, the visit is no longer a lameness exam, it’s an emergency, and my priority will be to stabilize the limb while we decide how to proceed.

Thankfully, I usually don’t find anything that dramatic on the leg or body, so I turn my attention to the hoof. In a large portion of the country, including where I practice in Virginia, a horse who goes horribly lame in a single limb without any other sign of injury usually has a hoof abscess. I’d even put it as high as 90 percent of these types of exams lead to the diagnosis of a hoof abscess.

It’s a fairly easy call to make: First, I’ll use a hoof tester to try to pinpoint the exact location of the pain. Similar to a large pliers, a hoof tester is used to compress specific areas of the hoof. Squeeze hard enough and any horse will flinch, but if he pulls away from pressure that just a few inches away didn’t even register, you’ve found the trouble spot. I’ll methodically work around the hoof wall, across the sole and the edges of the frog to test all the possible locations.

When I’ve located the area of pain, I may use a farrier’s knife to pare away a bit of sole and look for an abscess. If it’s shallow, the pus will drain right then and there, to the relief of the owner and the horse.

So, if we’re all lucky, I can diagnose a hoof abscess, begin the treatment process and be off the farm in a half-hour. But we’re not always that lucky.


JOGGING IT OUT

If the hurt leg isn’t obvious when the horse is standing still, the next step is to watch him move. Some types of lameness can be seen when the horse is simply walking in a straight line, but many times a horse must be jogged and viewed from many angles and as he turns to make a determination.

I usually have an assistant on hand to jog a horse for a lameness exam. Not IN A PINCH: I use hoof testers to pinpoint painful areas on the hoof. These are particularly helpful in diagnosing hoof abscesses, which are common in my practice area. OUT AND BACK: As the horse jogs, I look for gait irregularities as well as the telltale head bob of lameness. Not only does this spare an owner from having to run back and forth for several minutes, but it allows her to observe what I see, at the time I see it. This makes it easier to explain what it all might mean.

My assistant will first walk and then jog the horse in a straight line away from me over a relatively firm surface ---a driveway works well. I’ll then watch the horse head back toward me and, if necessary, move to one side so I can watch him walk and trot across my line of vision. It’s important that the horse be allowed to move freely, so my assistant will jog him on a loose lead, not dragging him behind her. Initially, I try to look at the whole horse to get the big picture, but one of the first things I focus on is head movement.

When a horse puts weight on a sore limb, he’ll lift his head to relieve the pressure quickly. That’s what creates the distinct head bob of lameness: A horse lowers his head when his good limb is on the ground and raises it when the “bad” limb bears weight. When the lameness is in a forelimb, this bobbing may be paired with an obvious favoring of a leg. When it’s a hind limb, detection can be trickier, but I’ll watch for one hip carried higher than the other or a hind foot that is not brought as far forward as the other. Additional clues include how far each fetlock drops as the leg bears weight and the sound of the hooves striking the ground, which can tell me which leg is getting more or less weight as the horse moves.

Some types of lameness become apparent only when a horse turns, heads off or moves in some other specific way. I may have the horse longed in different-size circles or trotted up and down a small hill to get a better look at a subtle gait abnormality. I’ll also rely on the owner to tell me where and when she’s noticed the lameness so we can attempt to re-create the conditions where it is apparent. This is a bit like taking a clunking car to a mechanic: If it doesn’t make the noise when it’s at the shop, there’s little that can be done diagnostically.

Some lamenesses are obvious only when a horse is under saddle. I’ll usually hear from the owner that “he looked perfectly fine until I got on him.” In these cases, I’ll still have the horses jogged in-hand to see if I can detect what the rider feels under saddle, but I’ll occasionally end up also asking that the horse be ridden while I watch. Sometimes bearing the rider’s weight will intensify the problem to the point where we can isolate which limb is involved, but not always. There are lamenesses, most often found in elite competition horses, that only riders can feel, and they are understandably very difficult to unravel.

FLEXION TESTS

Once I’m confident I’ve narrowed the problem to a particular leg, I’ll inspect it and go over it with my hands for any sign of trouble I may have overlooked initially. I’ll also compare it to the opposite leg to look for dramatic differences. Even if it seems certain that the problem is somewhere else, I will put hoof testers on the feet. The foot is the most common source of lameness, and there can be more than one area of discomfort.

It’s helpful if I have had an ongoing relationship with the horse, so I’ll probably know whether the swelling on his fetlock is an old windpuff or something more recent and sinister. If I don’t have a history with the horse, I’ll have to ask the owner and hope she recalls.

If the source of the problem is still elusive, I move on to the flexion test, a time-honored and relatively easy method for pinpointing lameness. For this test, the veterinarian forcibly bends a joint for about 30 to 90 seconds, then has the horse immediately trot off. The flexing stretches the joint tissues, causing pressure to build up and temporarily intensifying any soreness. If, for instance, a horse seems slightly off on his right fore when jogging out but then is dramatically lame after his right front fetlock is flexed, that may narrow the investigation down to that joint.

The results of a flexion test, however, have to be considered carefully. Horses have varying levels of sensitivity to the test. An otherwise sound 20-year-old lesson horse, for example, might hobble off after I flex any joint simply because he’s got more miles on him and a bit of arthritis in every joint. In contrast, a tough-as-nails Appaloosa might not even flinch, no matter how hard and how long a sore joint is flexed. For that reason, many veterinarians will flex the corresponding joint on the “good” leg before flexing the suspect one on the bad leg. This lets us know how the horse normally reacts to flexion so we can keep his reactions in context. I’ve had many owners tactfully point out to me that I’m flexing the wrong leg before I can explain this to them.

If I get a “positive” flexion in a joint, I can do several things with that information. We could then take radiographs or do an ultrasound examination of that joint to gather even more information. Or, if the flexion test confirms a strong suspicion, we may stop the lameness exam, make a preliminary diagnosis based on the information we have and begin to outline a treatment strategy.

NERVE BLOCKS

Sometimes, however, the flexion tests don’t pinpoint the problem as I’d hoped. In these situations, there’s another diagnostic technique veterinarians can turn to: blocking, the injection of a small amount of anesthetic directly into nerves, just under the skin, in strategic locations of the leg. Most sites require two injections; some a few more. The limb will become temporarily numb from the site of the injection down to the ground, so we begin numbing from the bottom up until the horse jogs off sound.

If, for instance, I numb the hoof and the horse is still lame, I numb the pastern area. If the horse is still lame, I move up to the fetlock. If the horse suddenly goes sound, we can be pretty sure there’s something in the fetlock area causing the problem. Sometimes, if  I’ve got a strong suspicion about a particular joint, I may skip ahead and numb a higher joint first. This saves everyone time and the owner money but comes with the risk of confusing results.

Nerve blocks also can help uncover multiple limb lamenesses.  I’ve had this happen to me more than once: I block the obviously lame leg, only to have the horse suddenly come up lame in what I thought was the “good” leg. This means the horse was sore in both, but we were only noticing the worse one. This happens quite a bit in horses who are “footsore” in multiple hooves, and it is very useful information to have.

Nerve blocks are typically limited to below the knee and the hock. You can do them on higher nerves, but it gets tricky to access them and interpret what you’re seeing. Whether your regular veterinarian uses a nerve block higher in the limb depends on her experience and comfort level with the procedure and lameness exams in general. We are explaining this procedure in a simple way, but as with all things having to do with horses, there are exceptions and details that can make the process more complicated than it seems at first.

WHEN THE ANSWER IS STILL NOT CLEAR

If I’ve just spent an hour watching a horse trot, flexing each joint and blocking half a dozen areas, and still nothing on his body says “Pick me, pick me!” I stop and discuss a few options with the owner.

One is to focus on the problem most likely to be causing the lameness and start treating it. We won’t be guessing blindly, though. We’ll use the evidence we’ve gathered during the exam, combined with what we know about how this horse has been used recently as well as his lameness history. This approach is an excellent choice if your budget is limited, your horse doesn’t “have” to be sound immediately, or resources for a more in-depth investigation simply aren’t available in the immediate area. Ideally, we’d have a definitive diagnosis for every lameness problem before we begin treatment, but that’s not always possible. Thankfully, rest and anti-inflammatory medications are the proper treatment for most minor---and even some major---lameness issues, so going that route is likely to help in most cases.

The other option is to refer the horse to a large clinic or university facility that has more state-of-the-art diagnostic imaging equipment. Many field practitioners today have digital radiograph machines and ultrasound equipment, but you’ve got to know where to point them or you’re in for a very long and potentially expensive exploratory mission. And even when you have an idea where to look, some of the portable radiography and ultrasound machines aren’t as powerful as the ones found at clinics.

Images in the field may come up “clean,” but images of the exact same area taken with newer equipment might reveal the problem, making the referral worthwhile. Often the team of board-certified experts at the clinic will see problems your regular veterinarian could not due to the combination of their specialized training and experience, their equipment and facilities and---sometimes---because the horse simply looks different on a different day. Comparisons of images taken over the course of weeks or months can also help with some diagnoses.

In addition, larger clinics will have the capability to perform lameness diagnostics that just aren’t possible on the farm. Nuclearscintigraphy, also known as a “bone scan,” is an imaging process in which a horse is injected with a radioisotope that naturally collects at areas of active bone metabolism, such as an injury site. Specialized cameras are then used to detect areas of increased uptake, which can help direct other diagnostic efforts.

Scintigraphy can detect bone problems in the upper limb, pelvis and back, which are extremely difficult to radiograph, and can detect multiple problem sites during the same test. You run the risk of a spot that doesn’t hurt the horse coming up “hot” because of natural bone remodeling, but you can typically sort through those false alarms. All in all, it’s an extremely useful tool and a relatively easy test.

Magnetic resonance imaging (MRI) is another diagnostic tool available only at large clinics. MRI uses radiofrequency pulses and strong magnetic fields to produce incredibly detailed images of “slices” of the horse that show both bone and soft tissues. It’s amazing technology, but with some limitations. The horse has to be anesthetized for most MRIs, although there are some “standing” machines in a handful of clinics. Also, veterinarians are still learning to interpret MRI images to determine if what we are seeing is normal. And, last but not least as far as owners are concerned, MRIs can be very expensive, so you’ll need to have narrowed your search down to a specific limb or area before you start.

There’s a wave of research leading to all types of computerized systems that analyze how a horse is moving to detect lameness. One, aptly called the Lameness Locator, utilizes sensors and gyroscopes to track the movement of a horse’s head and hindquarters. The collected data are then presented as charts and graphs that can be interpreted by the veterinarian to determine which leg is lame.

While these developments are certainly exciting, we aren’t at the Star Trek scanner phase quite yet: A computer can pick up subtle differences in movements the human eye can’t, but it’s still up to a veterinarian to investigate why a limb is moving differently than the rest.

When you arrive at a referral clinic for a lameness exam, don’t be surprised when the consulting veterinarian starts back at square one, watching the horse jog. It’s not that they don’t trust the information provided by the initial veterinarian, but lameness exams really are “big picture” events, and it’s important for each veterinarian involved to see everything.

They’ll bring out the big diagnostic guns soon enough, but they may also see something new on the preliminary exam that solves the mystery and saves everyone a lot of time and you a lot of money.

Lameness exams are an attempt to impose logic and order on what can be a very messy, complicated problem. Sometimes this works well, and a veterinarian can unravel tangled and overlapping signs to quickly get a clear picture of why a horse is limping. In other cases, however, the exam becomes a test of the veterinarian’s experience and instincts as well as the patience of everyone involved. Even so, it is still our very best tool for keeping horses sound and one that all horse owners benefit from understanding.










This article is copyrighted and first appeared in EQUUS Magazine. It is reprinted here by permission.


Tuesday, March 10, 2015

Romulus the Dressage Horse

Secret Lives of Horses

By Mary Jane Howell, photography by Gary Knoll

The twins Romulus and Remus may be the main characters in Rome’s creation myth, but Aiken has its own Romulus and he has four legs, not two. His owner Melanie Mitchell likes to point out that the 23-year-old gelding does have a Roman nose, but that’s his closest tie to Italy!

Although he has some gray hairs on his face, the 16.3 Westphalian shows no other signs of his age. Retired from a promising dressage career many years ago due to chronic front feet issues, Romulus was never happy without a job, so he became Melanie’s go-to lesson horse and babysitter when she moved to Johnston in 2006.

Melanie is a native Californian and it was there that she first saw Romulus. Shelley Lawder, a well-known dressage trainer, had brought him over from Europe to be her international horse.

“I will always remember the first time I saw Romulus,” recalls Melanie. “Shelley had called me to look at a Thoroughbred mare that was for sale. As I drove to her barn I saw this incredible looking bay in one of the pastures – even from a distance he had that ‘Wow’ factor. I thought to myself, ‘Why can’t I have a horse like that one?’”

Melanie did not purchase the Thoroughbred mare and it was a few months later that Shelley once again called her, with those magical words: “I have your horse.”

The horse was Romulus.

“He came up for sale due to a wide variety of circumstances,” explains Melanie. “It took several months for me to actually get him but he was everything I had wanted in a horse and more. I wanted a horse who had been well taken care of and had a good foundation as far as training went. Shelley had already shown him at Training level and done well.”

Melanie says it took her a few months to really get to know Romulus, even after reading the “Owner’s Manual” that Shelley had written for her.

One of the first things Melanie did was to take her new horse to a clinic taught by Jane Bartle.

“I entered the ring the first day with big spurs, a whip, a flash noseband and draw reins,” laughs Melanie. “Jane took a long look at us and simply said ‘We’re taking everything away and then you will learn to ride him correctly.’”


This was during the late 1990s, when Melanie was the owner and operator of a very successful dog grooming business. She had a store and two mobile grooming vans. Horses were her first love, however, and she would get up at 4:30 each morning to ride Romulus before starting her workday. It should be noted that while Melanie worked hard, overseeing a staff that groomed 100 dogs a day, Romulus spent his leisure time atop the Palos Verdes Peninsula, in a gated equestrian community with an ocean view.

Melanie showed Romulus an average of five times a year, working up to Prix St. Georges level and earning her USDF Silver Medal. Romulus was 10 when Melanie showed at Del Mar. “We did really well,” she says, “but he was unsound afterwards and that was the end of his show career, for the most part.”

“Romulus had a definite sense of humor,” Melanie continues with a laugh. “He loved to make me look foolish – for example, at Second Level he would do flying changes. When he had enough he would simply passage all the way back to the barn. It was never scary – not knowing what might come next in his repertoire – but I wish I could start all over with him now, having learned so much as a rider.”

By 2004 Melanie was getting tired of dog grooming and began looking for another career. A major door opened for her when she was hired by Charlotte Brehal-Baker, an Olympic rider, to be her assistant trainer.

Although she was riding many of Brehal-Baker’s horses and learning her training techniques, Melanie still rode Romulus when he was sound enough. She also met Nicho Meredith at this time. Nicho is a popular, multilingual horse show announcer who travels the world while plying his trade.

With California becoming so expensive, Melanie, Nicho and several horses made the move to the Aiken area in 2006. They have never looked back. They named their farm Aloha Acres, a tip of the hat to their memories of Hawaii, a favored vacation spot.

Although there are currently 25 horses that call Aloha Acres home, there is only one king, and that is Romulus. Melanie quickly realized that he needed to be given some type of job because without work he became quite depressed.

“The sandy soil really helps his soundness issues and we keep him shod,” she says. “There is no reason why he can’t work a bit and for me that means being a lesson horse as well as a confidence-booster.”

Romulus got with the program right away. One of Melanie’s clients was preparing for a show when her horse developed a hoof abscess. With three days to go, there was no way her horse would be sound before the competition, so Melanie made the decision to let her ride Romulus.

“One of the most unsettling parts of a show is the warm-up ring and all the activity – horses passing you, horses coming towards you – and Romulus really took care of this woman. He gave her so much confidence.”

The pair scored 67% and Melanie chuckles when recalling that the judge’s comments included the statement “Your horse shows excellent potential to move up through the levels.” Little did she know whom she was dealing with!

Katie Roth is another of Melanie’s clients, and she has first-hand experience of what an exceptional horse Romulus is:

“I’ll thank Melanie a million times over for allowing me to ride Romi when I was coming back from an injury and had lost my confidence. Romi took care of me and taught me so much about dressage. It’s an absolute privilege to sit on a horse of his caliber and I am grateful for all the lessons he taught me. He is a kind soul who holds a special place in my heart.”

“Romulus takes pleasure on helping riders, but he also is a good trainer,” says Melanie. “If I am giving a lesson and the rider is sitting incorrectly, he will just stop until he feels the position is right. That is priceless.”

Romulus has a simple diet of senior feed, beet pulp and timothy hay. He loves his stall and hates the summer bugs. He loves being in the mix of things, even if it’s just standing in cross-ties as an interview takes place.

“Everyone who meets him falls in love with him,” Melanie says. “They may love him, but he is my special guy, my one-of-a-kind, once in a lifetime horse.”



This article is copyrighted and first appeared in The Aiken Horse. It is reprinted here by permission.