"Slo-Mo" Normal Video vs. "High Speed" Video: Why HS Counts in Gait Analysis

People love to take videos of their horses and then play them back in slow motion, but are ultimately disappointed when their clips don't have the detail that you see in a presentation by Drs Hilary Clayton or Alan Wilson, or in the toe-grab research footage shot by farriers Mitch Taylor and Scott Lampert. And why can't you see that twisting hock action in your videos that Haydn Price shows in his lectures? You know it must be there. Worse yet, speakers at conferences are horrified when their videos project as pixelated blurs in motion on the big screens. "It looked great on my laptop," they mumble.

What's the problem? With digital cameras, it's easy enough to understand the concept of "resolution", or pixels per inch. In an oversimplified nutshell: The higher the resolution, the more pixels per inch. The more pixels per inch, the sharper the image looks when printed on paper. Low-res images usually look ok on computer monitors because the monitors are low-res, too but they won't print in a magazine.

With video, if you want to slow something down, you need a lot of "frames" to see the phases of motion. High speed video delivers those frames, but it is very expensive, and also the very best way to look at a horse's foot in motion.

In the clip above, you are seeing the exact same footage, shown at three different speeds.

My favorite video clip, along with the Danish mousetrap, is one that Dr. Clayton likes to show when she speaks. She shows it first at normal speed: a horse trots across a force plate. There is a little glitch in the action, you see his head lower but you might not give it a second glance.

There's always some clever farrier in the audience who, as this juncture, blurts out: "He pulled a shoe". Most people don't realize it happened.

When she slows the high speed down, you see the hind foot reach forward and catch on the heel of the front shoe. For several tortured frames, front and hind are locked and the horse careens forward in a sliding motion--that would be when the horse's head goes down for a split second.

Then the shoe comes ripping off the foot and the entire lower limb is wrenched so that you would think the pastern would come unhinged. You swear the shoe will take half the hoof wall with it. It flies through the air, somersaulting in slow motion, much like the mousetrap in today's video.

Some barefoot advocates have to leave the room at this point.

And the horse keeps going, as if nothing happened.

High speed video has been a great gift to anyone interested in how horses move. The name is deceptive, since it is not speeding up at all. What it does is allow us to slow motion to a crawl and see every exaggerated detail. We see that little twisty rotational move before breakover. We see the slip in landing. We see that horses rarely, if ever, land symmetrically, even though it may look that way on normal video in slow motion.

Do you need a megabucks camera to record horses in motion? Certainly not. I know of people doing very clever things with decent cameras bought on sale day at Best Buy. Out of the box sports coaching programs like MotionCoach can get you started and if Nokia's cell phone Golf Edition will video-capture your golf swing and analyze it in the palm of your hand, can a stride-length cell phone or a railbird accelerometer be far behind?

At the Badminton Horse Trials in England next month, and at other advanced events there over the summer, a special fence will be in use. Designed by an engineering project called "Competitive Measure", the ascending spread obstacle will have an accelerometer attached to it. If the horse touches the fence, the accelerometer will measure how fast the horse was going when it hit. But that's only half of it: the fence is rigged with a built-in high-speed video camera that will record the horse's approach, the rider's position, the trajectory of takeoff and, should it go down, every detail of the fall.

There's no doubt that motion capture is looming in the future for riders and for their support teams. Just like the early days of the Internet, the best advice is to jump in and get your feet wet. Splash around at the shallow end of the pool and learn to use the cameras and editing software like iMovie, if you're lucky enough to have a Macintosh computer, or Final Cut.

By studying high speed clips from the pros, we can get inspired and we can relate to how difficult and time-consuming the work of true gait/motion analysis is, when proving or disproving lameness or a biomechanical syndrome is at stake. Video analysis will soon enhance the sales value of horses and track training progress. We'll take it for granted, but professional high-speed footage will still be the Holy Grail.

The way I describe it: It's like seeing a hoof--or a mousetrap--for the very first time.

Big Brown’s Trainer Richard Dutrow Says Kentucky Derby Favorite Benefited from Expert Farrier Care Before Florida Derby

In this fun video, you can watch Big Brown gallop nimbly around the track at Gulfstream Park, winning the 2008 Florida Derby in near-record time last week while wearing glue-on shoes to help his front feet, both of which have suffered painful wall separations. What could he have done that day if he was 100 percent? Listen closely to the altered-lyrics of this familiar Jim Croce song; glue-on shoes are having their praises sung!

In an interview today with Hoofcare and Lameness Journal editor Fran Jurga, trainer Richard Dutrow shared some insights into the hoof problems that have been in the headlines lately.

If his horse Big Brown, owned by IEAH Stables Inc., can win the Florida Derby in near-record time from the outside post position with two hoof wall separations and special shoes glued on his feet, what might this horse be able to do if he was sound?

Dutrow said that when he arrived at his barn, Big Brown already had suffered one quarter crack, or wall separation, which was repaired in New York by hoof repair specialist Ian McKinlay. Later, the horse developed a second separation, in his “good” foot, after being shipped to Florida. This repair was handled by Tom Curl, a Florida-based hoof problem specialist who works with Ian McKinlay.

Among the horses on Curl’s resume are Belmont Stakes winner Touch Gold and famed leading money-earner Cigar. He also helped Afleet continue his racing career as he ran in stakes races with the first glue-on race plates back in the mid-1980s.

Dutrow consulted his calendar and said that it has been 40 days since Curl repaired the second foot. He said the first one is all but “history”, but on the second (newer) one, the problem is still visible above the glue holding on the shoe.

On his hind feet, Big Brown wears normal shoes, but with turndowns. A turndown is an exaggerated heel calk, formed by twisting the heel of the shoe toward the ground like a spike. Turndowns are not allowed in New York.

Big Brown will not be in the spotlight at Churchill Downs and Keeneland, where most of the other Kentucky Derby candidates are training.

Dutrow said that Big Brown will stay in training at Palm Meadows in Florida, almost right up until the Kentucky Derby. He will fly to Louisville on the 28th of April, according to Dutrow’s current plans. The Kentucky Derby will be run on May 3rd.

“I see no reason to move him,” Dutrow said. “He’s better off. I’m happy to get him ready right where he is. He’s happy here.”

Dutrow had nothing but praise for McKinlay, who he said has helped him with hoof repair situations before, and Curl, who is close by in Florida. He said that it was great to have experts like them to turn to. “This horse is dodging his problems,” he said. “And he’s going to keep doing that.”

Please click here to learn more about quarter cracks and see a short video from Big Brown's consulting specialist Ian McKinley of a horse with a quarter crack.

Note: Most of the information published so far on Big Brown's glue-on shoes are about their very high cost. I am not sure how or why that information was given to the racing press, or if it is correct and whether or not that price included the patching, which is an involved procedure. There are many expenses involved in treating a complex wall separaton or crack and in gluing on special shoes. What matters is what the care and shoeing and patching allowed the horse to do. I hope to have more details about the shoes to post shortly.

All HoofBlog text and images © Hoofcare Publishing 2008 unless otherwise noted.

To learn more about new research, products, and treatments for the horse's hooves and legs as reported to veterinarians and farriers in the award-winning "Hoofcare & Lameness Journal",
go to http://www.hoofcare.com

Direct “subscribe now” link to Hoofcare & Lameness Journal: http://www.hoofcare.com/subscribe.html

Contact Hoofcare Publishing anytime:
tel 978 281 3222 email bloginquiry@hoofcare.com

Quarter Crack Repair: Why Hoof-Impaired Athletes Like "Big Brown" Need Expert Care

Click on the "play" button to see a closeup video of a quarter crack and the initial stages of the repair process typically undertaken on a horse that needs to stay in training. This video is by Ian McKinlay of New Jersey, the quarter crack expert consulted for Big Brown's hoof problem. The horse in this video is NOT Big Brown and this horse's problem is not identical to Big Brown's!

A freakishly fast young Thoroughbred named "Big Brown" won the Florida Derby last week in spite of having "quarter cracks", or wall separations, in both front feet. The "cracks" were immobilized and he was wearing specially-adapted glue-on shoes (more on them later). From the email queries coming in, it seems that a lot of people are not really sure what a quarter crack is and what it means to a horse...especially a horse who hopes to win the Kentucky Derby three weeks from now.

First of all, please understand that a quarter crack is a specific injury to a foot, but that, at the racetrack, people often refer to multiple problems as quarter cracks. There are also bar fractures, heel cracks, subsolar abscesses that affect the wall, and other problems that are repaired with patches or glues and, in backstretch lingo, are called "quarter cracks".

This article refers only to the explicit condition of an actual crack in the inside quarter of the hoof wall. It is a common problem for racing Standardbreds and Thoroughbreds.

A quarter crack is literally a fracture of the hoof wall through the area of the hoof known as "the quarter", a point where, more or less, the geography of the hoof wall completes its arc around the toe, and the heel region begins. Sometimes you can see where angles of the hoof tubules change between the heel area and the radial part of the hoof. Some farriers refer to toe quarter, "the" quarter, and heel quarter as regions of the hoof wall.

Obviously, the regions of the hoof are much more delineated on a larger foot,and much more visible on a white foot.

Horses usually get quarter cracks in the medial (inside) hoof wall, as opposed to the outside wall. This is generally believed to be because of the shear forces of the horse's weight from above that is either abnormally high on the inside hoof wall, or because the foot is misshapen or weakened (known as "medial-lateral imbalance"). Conformation, improper shoeing, neglect and poor quality hoof walls are some of the causes of quarter cracks but experts say that they are often surprised when relatively normal hooves develop quarter cracks, possibly as a result of training or running over hard ground or changing gait so that suddenly more of the horse's weight loads the inside wall.

In simplest terms, a quarter crack is like a split fingernail that goes right up through the cuticle. Ouch! Now, imagine standing and bearing weight on that cracked nail. And then imagine running on it. And Big Brown has two of these cracks, although they are both in the healing process.

This, of course, is a vast over-simplification of one of the most complex disorders that can affect a hoof, and is meant only as an explanation for people outside the hoofcare field who are asking for more information about what quarter cracks are.

To answer one question: No! Cracks are not like musical notes, there are no half or eighth hoof cracks, that I know about, anyway! (Great question!)

Dr. David Hood of the Hoof Project, in his great little book "Building the Equine Hoof", offers a simple explanation: "Deep cracks occur when loads placed on the wall are greater than the structural strength of the wall. Inadequate blood flow, lack of balanced nutrition, or improper cornification can lead to a weaker wall prone to cracking."

The goal of crack "repair" is not to heal the crack but to immobilize it so that new growth can begin. A very serious crack will damage the top of the wall at the hairline, called "the coronet" (crown of the hoof). This is the area where new growth starts, and scar tissue in the coronet will prevent normal growth. Sometimes the wall that grows down from the cracked hoof is a different consistency and the zone is always in danger of a repeat fracture.

You'll notice on the video how soft the hoof wall is on this Thoroughbred, particularly in the detached heel area.

There's no doubt that these young Thoroughbreds have thin walls and that they are prone to these cracks. It's also pretty amazing how they heal.

As nasty as a quarter crack looks, an expert patch job can keep a horse running. And winning. One of the most famous crack repairs was on Kentucky Derby winner Ferdinand back in 1987 when he ran by Alysheba to win the Breeders Cup. Ferdinand's crack was patched by California horseshoer Buzz Fermin. The great Standardbred Nihilator was known to have raced wearing "mushroom" shoes, which remove pressure from the heel area.

NOTE: This is not a "how-to" video. The hoof walls on these horses are incredibly thin and the skill that it takes to properly drill through the wall without damaging live tissue is critical as is the exact amount of pressure used when lacing. Ian has been doing this for as long as I can remember and his skill is remarkable. Don't try this at home.

Click here to read about an interview with Big Brown's trainer, Richard Dutrow, about the colt's hoof problems, shoes, and consulting farriers.

All HoofBlog text and images © Hoofcare Publishing 2008 unless otherwise noted.

To learn more about new research, products, and treatments for the horse's hooves and legs as reported to veterinarians and farriers in the award-winning "Hoofcare & Lameness Journal",
go to http://www.hoofcare.com

Direct “subscribe now” link to Hoofcare & Lameness Journal: http://www.hoofcare.com/subscribe.html

Contact Hoofcare Publishing anytime:
tel 978 281 3222 email bloginquiry@hoofcare.com

Palm Beach Footing Post Script

Palm Beach International Equestrian Center's International Arena during a recent night class

After posting on Friday about the footing at the Winter Equestrian Festival in Wellington, Florida, I have a few more comments to add.

I think this is the year of the surface: whether its show arenas, home schooling rings, or racetracks, everyone is talking about (and obsessing over) footing! No matter whom I'm with, the subject invariably comes around to it. And no, I don't know about much new research!

One vet said that he thought he had seen more bruised feet this season at Wellington but seemed genuinely pleased overall with the footing.

Show circuit farrier Jack Miller, who happened to cross my path at the airport this afternoon, concurred with the veterinarians' comments. We sat down to chat for a few minutes. He said that the new footing was much more consistent and enabled the show to go on, even after a downpour of six inches of rain. "The new footing was great," he said, "but a little sluggish. The horses were maybe jumping an extra two inches, because they were sinking in. It stopped them. And it cupped a lot out of the bottom of the feet. But it was a lot better than it has been, and they didn't have to use as many studs. We didn't see too many 'Spruce Meadows Specials' (supersized studs) this time."

Also at the airport today, I ran into another vet, Dr. Liz Maloney from here in Massachusetts, who has been flying back and forth to Palm Beach all winter to compete her horses in the amateur owner division at the WEF. She said that her horses, who are shod by "banana shoes" expert Danny Dunson from Tennessee, handled life on the showgrounds very well, although she didn't always compete in the newly renovated "Hong Kong footing" arenas. She said it was great to not to have to use studs, since she worries so much about the injuries they can cause. "It feels hard when you land, but it's not, really," she said of her impression from the saddle.

Other comments I heard were about the hunter ponies that compete barefoot and wore booties to get from the stable area to the arena and schooling rings, since the pathways were crushed stone. Show hunters want as little knee action on the flat as possible so no shoe or the very lightest aluminum shoe is usually the answer for them.

Everyone seemed pleased that the winter season in Wellington was unaffected by disease (EHV closed the showgrounds last year in the weeks before the show started) or disaster (hurricanes have been a threat the past few years) and that the upper echelons of the hunter/jumper/dressage showing scenes seem (so far) unaffected by financial woes troubling other sectors of the US economy.

Thanks to the Winter Equestrian Festival and Kenneth Braddick of Horse Sport USA for the excellent photos and reports shared with this blog all season. Now it's time to pack up and move on. See you next year!

Greetings from Florida: Vets See Happy Hoofprints in the Footing at Winter Equestrian Festival

I should be thinking about the bright blue sky overhead, but this post is about the ground beneath our feet, instead.

The fabulous Winter Equestrian Festival has melted into spring and the newly-renovated arenas at the Palm Beach Equestrian Center have endured thousands upon thousands of hoofprints. The WEF's signature green grass of past years is a memory.

And now it's time for two of the circuit's veterinarians to update us on how the footing worked for the horses this winter.

Dr. Timothy Ober, veterinarian for the U.S. Equestrian Team and a member of the U.S. Equestrian Federation Equine Drugs & Medications Committee, said, "We have no statistics as such, but it seems there are fewer injuries. The horses are holding up better."

Dr. Scott Swerdlin, president of the Palm Beach Equine Clinic, the official veterinary service for WEF, said: "There are fewer catastrophic injuries. Aa result, the veterinary community is excited about the new footing which has been spectacular."

The vets gave their opinions as the CN Winter Equestrian Festival presented by Zimmerman Advertising wound up 12 weeks of competition that began on January 16.

Footing created by Bart Poels, the 2008 Olympic equestrian footing expert, and installed by Poels and Brett Raflowitz of Palm City, Florida, was installed in the two jumping Grand Prix arenas at Palm Beach International Equestrian Center.

In the centerpiece International Arena alone, more than 7,100 "trips" (not including jumpoffs) were completed by hunters and jumpers during WEF. A four-day dressage competition required that two dressage arenas be installed in the International Arena.

Thousands more horses competed in the Bertelan DeNemethy Arena in which the "Poels" footing was also installed, as well as several other competition and warm up rings, including the Grand Hunter and Rost arenas and Ring 6.

Equestrian Sport Productions, LLC, the PBIEC management company, announced that the "Poels" footing will be installed in the Mogavero ring over the summer.

Before the start of WEF, ESP placed the highest priority on improvements in the footing throughout PBIEC to enhance the safety and welfare of horses.

Among the events held in the International Arena was the five Selection Trials for the short list for 2008 Olympic jumping team. And the show grounds were inundated by record rain fall during the course of WEF.

Dr. Ober, who attended the U.S. equine athletes at the 2004 Olympics in Athens, the 2006 World Equestrian Games, and dozens of the other international competitions, said: "Horses in the trials were in good order. That is an example of how the footing has been beneficial. Compared to past trials, the attrition rate seemed smaller and that primarily is due to the footing.

"There was a little bit of a learning curve with the new footing. The type of footing requires an adjustment because it does not allow the foot to glide.

"The footing has been a real positive, mostly for the good of the horses that always come first. But without it, because of the weather, there might not have been the competitions we were able to have."

Thanks to Kenneth Braddick of the Winter Equestrian Festival for help with this report.

Safety Warning: Work-Related Pregnancy Problems in Female Veterinarians

Female veterinarians have twice the risk of miscarrying as a result of increased exposure to anesthesia gases and pesticides, according to a study released on April 1, 2008 in the journal Occupational and Environmental Medicine. These results highlight a warning for all young female vets, who must be made more informed of the inherent risks should they want to become pregnant.

This work was done as part of a study known as the Health Risks of Australian Veterinarians Project (HRAV), surveying all graduates from Australian veterinary schools between 1960 and 2000.

In all, 5,700 graduates were contacted, of which 2,800 responded. Of these, 1,200 were women. Within these female respondents there were 1,355 pregnancies reported, 940 of which took place while the woman was working in clinical practice. This group of pregnancies was considered eligible for inclusion in the study.

Women who carried out surgeries and were exposed to unfiltered anesthesia gases for an hour or more a week had 2.5 times the chance of miscarriage. The same was true for vets who used pesticides in their work.

Female veterinarians who performed x-rays more than five times a week had 1.8 times the chance of miscarrying. The trend appears to be consistent over time, as when the analysis was restricted to recent graduates (between 1980 and 2000), the results were similar.

This prompts the authors of the study to sound a warning to female vets who are of childbearing age, that they "should be fully informed of the possible reproductive effects of ionizing radiation, unscavenged anesthetic gases, and exposure to pesticides."

This warning could potentially apply to other staff members in equine veterinary practices as well. Thus, the authors advise that these women should take protective measures when planning to conceive and during gestation.

Article title: Maternal occupational exposures and risk of spontaneous abortion in veterinary practice
Authors: A Shirangi, L Fritschi, CDJ Holman
Journal cited: Occupational and Environmental Medicine 2008

This summary was brought to the HoofBlog's attention through a daily RSS feed from Medical News Today, a news aggregation service for the medical profession. The summary appears with the permission of the editor.

Photo at top by photographer Jan Verbeke, aka JeBeKe, of Belgium.

flip, originally uploaded by Rachel Robot.