From Sim to Mo-Cap to Slo-Mo: Have Another Look at the Horse in Motion

by Fran Jurga | 28 October 2009 | Fran Jurga's Hoof Blog

Today I hurt my eye and it made the world a different place. Depth perception was different, some things don't quite line up, and this computer screen is a little blurry so this post will be a media-rich one. I'll let the videos tell the story.

And the story is exactly what I have been experiencing: how do we look at things? You read research reports and case studies and observations on this blog all the time, but they are from the viewpoints of different original sources. Here are some examples of the sources the Hoof Blog uses.

This is a computer-generated leg model from the University of California at Davis. The model lives in a perfect world. Someone designed a limb with arbitrary (or perhaps intentional) conformation and measured the resulting tendon, ligament and muscle forces if this ideal limb was moving over a perfectly smooth, non-deforming surface.

This is what we now call "traditional" two-dimensional video analysis, often used for before-and-after shoeing and trimming evaluation.

This very brief clip is 3-D analysis. You might want to use the play button to start and stop it and see more detail.

Finally, here's high-speed video, or what you might call high-quality slow motion. This polo pony is exhibiting the same stride characteristic as the computer model at the top but wow! he is influenced by the weight and lean of his rider and the variable deformability of the field as well as, no doubt, probably some conformational traits that offset his limb alignment. This is the real world.

There are plenty of other ways to capture horses and model their movement to study and analyze them; the idea here is that when you read an article, the authors may be extrapolating data from a computer model or from subjective observation with no data collection. You have to read the fine print and always take into consideration how a study was conducted and how many horses were in a study.

Does the moving horse interest you? Cornell University will host a veritable festival of motion capture, slo-mo and gait analysis at the 26th Farriers Conference November 14-15 in Ithaca, New York at the College of Veterinary Medicine. The early registration deadline is Friday so get organized and save $50 over the on-site fees.

Speakers at Cornell include farriers Scott Lampert of OnTrack Equine in Minnesota and Mark Aikens from Anglia Equine in England, both of whom are leaders in using videography in analyzing how shoeing and trimming effect horses' movement. Dr. Jeremy Rawlinson of Cornell will demonstrate the use of Cornell's force plate system and de-mystify the concept of ground reaction forces.

Hoofcare & Lameness is thrilled to be a part of this event. For a full schedule and list of speakers, and to register online, click here or go directly to http://www.vet.cornell.edu/education/conferences/farriers/


© Fran Jurga and Hoofcare Publishing. No use without permission. You only need to ask.

Fran Jurga's Hoof Blog is a between-issues news service for subscribers to Hoofcare and Lameness Journal. This blog may be read online at the blog page, checked via RSS feed, or received via a digest-type email (requires signup in box at top right of blog page).

To subscribe to Hoofcare and Lameness (the journal), please visit the main site, www.hoofcare.com, where many educational products and media related to equine lameness and hoof science can be found.

Questions or problems with this blog? Send email to blog@hoofcare.com.

A Tribute to Bracy Clark: It's the 200th Anniversary of Natural Hoofcare

by Fran Jurga | 26 October 2009 | Fran Jurga's Hoof Blog

What year is it?

Patrick Ryan was, according to this slip of paper, a doctor (?) of horseshoeing in Baltimore, Maryland in the late 1800s.

You might have to double-click on the image to read the fine print, but across the top of the bill head, Mr Ryan promises "Horses Shod According to the Natural Formation of the Hoof. Satisfaction Guaranteed."

There's nothing new about the new school of thought on natural hoofcare. In the 1800s, a legion of learned professors and prickly posers preached any number of plausible and implausible theories about the so-called natural function of the hoof, as they interpreted it to be at that time. Most of the theories involved employing the frog by using a thin shoe or even a three-quarter shoe that exposed the heels and base of the frog to concussion, in the belief that that would stimulate the pumping action of the frog.

Professor Bracy Clark in England was the leading proponent of truly natural hoofcare, and his writings are quite interesting and worth a read. Just the reverse of Ryan in Baltimore, he was a veterinary surgeon--in the earliest days of the profession--who left academia behind and chose to shoe horses and study the hoof for the rest of his life.

Professor Clark enjoyed a renaissance about ten years ago when Dr Hiltrud Strasser chose selections from his vast body of writings to defend some of her theories. What many people missed was that he was a highly respected veterinarian and actually has a very broad body of writing on the anatomy and function of the foot and its diseases, far beyond simply expressing displeasure with shoes. In fact, he tried tirelessly to invent horseshoes that would work in harmony with the natural function of the foot and not stifle it.

The author/historian Major-General Sir Frederick Smith writes of Bracy Clark, "No writer in the profession before or since [his] day has brought to bear such a degree of scholarship."

In fact, Bracy Clark's first writings were exactly 200 years ago, in 1809. So let's tip our caps to him today. I recently learned that a packet containing Professor Clark's 1809 manuscript sold at auction for 3,130 British pounds--that's roughly $5,000 for some very frail old farrier papers.

Bracy Clark's forge near London's Regent's Park

To quote from an article by Ian McKay in the October 2009 edition of Book Dealer:

...This little collection opened with an illustrated 1809 account of A Series of Original Experiments on the Foot of the Living Horse. On the back of the frontispiece to this main work is a tipped-in prospectus in which Clark explains that he plans to publish his discoveries from time to time but ‘…must depend upon the intelligent and opulent for support in reimbursing the expenses…’, while bound in at the end is a single explanatory leaf, titled A New Exposition of the Horses Hoof, that refer to a pasteboard model of that equine extremity.

Other tracts in this little volume included Essays… on …the Nature and Cure of the Split-Hoof, Vulgarly Termed Sand-Crack and …the Causes and Cure of Running Frush in Horses’ Feet, both of which are dated 1818, plus another of 1822 …on the Canker and Corns of Horses’ Feet.

Another of the seven items that make up the collection is the advertisement ...., in which Bracy Clark announces that he has retired from all work with horses, ‘except what relates to the feet only’, and has opened a "…forge, in the Edgeware Road, near the Paddington Turnpike, for shoeing Saddle Horses, more especially, upon a New Plan, which admits the natural expansion of his Foot, and is more durable than the common shoe."

I got out my magnifying glass and was able to read some of the tiny print in Professor Clark's ad. I could read that he added at the bottom "Shoes made and sent (for ready money) to any part of the kingdom. No rasping off the natural rind of the hoof, no frog scalping--or notching of the heels allowed. A lecture on shoeing and the nature of the foot is delivered by the inventor the first Monday or every month at 12 o'clock. Admission 5 shillings." He would teach "professional characters" how to shoe according to his method for one price, and the sons of shoeing smiths for a reduced rate.

And now the big question: who bought these precious historic manuscripts? And what will he or she do with them?



Click here for original document: Bracy Clark Expansion Shoe -

Here's Bracy Clark's treatise on his tablet expansion shoe; the images are on the last pages. You can click on "full screen" at top right of the image box to read it easily and print it. The pages may load slowly, depending on the speed of your connection. I hope you will read it and realize how articulate this man was in describing the foot and his theory of hoof expansion. Read the part where he says that this shoe is his gift to horses, and that he is not patenting it so that more horses can benefit from it. In that sense, reading this reminds me of the Steward Clog.

What would I give to go back in time and head to Regent's Park for one of his Monday lunchtime lectures? This fellow's writings are worth a read, a re-read and many good long discussions to see where and how we've changed the way we look at the hoof's function. What would he say if he showed up today?

© Fran Jurga and Hoofcare Publishing. No use without permission. You only need to ask. Fran Jurga's Hoof Blog is a between-issues news service for subscribers to Hoofcare and Lameness Journal. This blog may be read online at the blog page, checked via RSS feed, or received via a digest-type email (requires signup in box at top right of blog page). To subscribe to Hoofcare and Lameness (the journal), please visit the main site, www.hoofcare.com, where many educational products and media related to equine lameness and hoof science can be found. Questions or problems with this blog? Send email to blog@hoofcare.com.

Next Stop on the Pub (Art) Crawl: England's Old Smithy Pub

by Fran Jurga | 24 October 2009 | Fran Jurga's Hoof Blog

Old Smithy, originally uploaded by ronclark5329.

Here's the second stop on our tour of the great pub signs of the world that honor the horse's hoof and its culture and craft. I don't know where The Old Smithy is, but perhaps one of the blog's readers from the British Isles will fill me in.

Thanks again to Mr. Ron Clark, the expert and tireless photographer of interesting pub sign art, for capturing another beautiful sign to share with us.

I thought this image was just stunning and if I was driving down the road and saw this hanging from a building I'd probably smash into something (although I usually do that anyway when I drive in Britain).

I think the artist was pretty creative on this one: what do you see in this picture that you probably wouldn't see in real life...on either side of the Atlantic? Click on the word "Comments" below and type in your answers.

Blue Tongue Dressage: Hyperflexion Still a Welfare Issue

by Fran Jurga | 23 October 2009 | Fran Jurga's Hoof Blog



This video clip was shot at an FEI World Cup Dressage qualifier in Europe last week. Luise and Julie from Epona TV were surprised that a rider at this level schooled this stallion for as long as two hours in a hyperflexion frame.

They grabbed the camera when they noticed that the horse's swollen tongue had turned blue. The horse's lips were curled and apparently even the rider could see it, as he stopped and put the horse's tongue back into its mouth.

Apparently the schooling ring steward did not see anything wrong with this rider's method.

Click here to read the full story about this videotape and about the effects of the curb rein and bit of a double bridle on the horse's tongue.

FEI rules discourage what is called hyperflexion, rollkur or "bite the chest"--riding with the horse in an overbent neck and head position for a prolonged period of time. The practice is the subject of last year's best-selling horse book, Tug of War: Classical vs Modern Dressage by German veterinarian Gerd Heuschmann.

Since last spring, Heuschmann's DVD If Horse's Could Speak has been on sale and goes even further than the book to tie overschooling, disconnected riding and especially overflexion/rollkur to unsoundness and musculoskeletal injuries in dressage horses. But it is very, very hard to prove the dots are connected.

Here's a clip from the If Horses Could Speak DVD (this is a German trailer, even though the actual DVD has an English soundtrack, not subtitles):



The DVD is 75 minutes long and is sold in North American format (NTSC) format. The cost is $60 per DVD plus postage. Click here to read more and order from our secure web page. You can order the book as well.

I thought that by the time the DVD was translated and available here in the USA the subject of rollkur would be forgotten but I guess that is not the case.

In a special interview with Olympics champion Anky Van Grunsven on Epona TV, Anky defends her use of hyperflexion as a training method, saying that she uses it for a few minutes at a time, then lets the horse relax, but that she only uses it on her advanced horses, and horses that are strong enough to do it, and for whom it is easy to go to that frame. She said she varies the time that she stays in the overbent frame from horse to horse, depending on how strong the horse is and how it reacts to being in that frame.

In a riding demonstration, Anky pointed out that her horse was pricking his ears while in the overbent frame.

Julie and Luise's Epona TV is a subscription-based library of equitation-science videos with interviews and demos by Gerd Heuschmann, Hilary Clayton, and many behavior and welfare experts. They are making a tremendous effort to provide a service that is a level above what you will find almost anywhere else on the Internet.


© Fran Jurga and Hoofcare Publishing. No use without permission. You only need to ask.

Fran Jurga's Hoof Blog is a between-issues news service for subscribers to Hoofcare and Lameness Journal. This blog may be read online at the blog page, checked via RSS feed, or received via a digest-type email (requires signup in box at top right of blog page).

To subscribe to Hoofcare and Lameness (the journal), please visit the main site, www.hoofcare.com, where many educational products and media related to equine lameness and hoof science can be found.

Questions or problems with this blog? Send email to blog@hoofcare.com.

World Champion Anvil Shooter at Work

by Fran Jurga | 21 October 2009 | Fran Jurga's Hoof Blog



Our mid-week humor is provided by a demonstration of anvil shooting, which is usually pretty entertaining in itself but the fact that the main character in this YouTube video claims to be the world champion suggest that there is some sort of a competition in anvil shooting.

How on earth would you judge the winning shoot? Are points given for technique or difficulty? I might have to get some ear plugs and a helmet and go check this out. The failures might be entertaining.

I thought anvil shooting was illegal; obviously it is not in the state of Missouri.

© Fran Jurga and Hoofcare Publishing. No use without permission. You only need to ask. Fran Jurga's Hoof Blog is a between-issues news service for subscribers to Hoofcare and Lameness Journal. This blog may be read online at the blog page, checked via RSS feed, or received via a digest-type email (requires signup in box at top right of blog page). To subscribe to Hoofcare and Lameness (the journal), please visit the main site, www.hoofcare.com, where many educational products and media related to equine lameness and hoof science can be found. Questions or problems with this blog? Send email to blog@hoofcare.com.

Breeders Cup: The Agony of De Feet

by Fran Jurga | 21 October 2009 | Fran Jurga's Hoof Blog

What kind of horse shoe is this?, originally uploaded by Rock and Racehorses.
Imagine the confused looks when someone spots this horse's hoof print.

The Daily Racing Form announced today that the defections are beginning; the field for next month's Breeders Cup Classic has lost a few interesting entries.

First it was the news that the fast-closing gray Macho Again would not make the trip west to Santa Anita after developing a cough while training at Churchill Downs in Kentucky.

Then it was the withdrawal of California-based Rail Trip, pulled from contention because of bruised frogs. Apparently Rail Trip sloughed his frogs after his last start at Del Mar and his feet are still tender, according to Steve Andersen of the Form.

The race is still three weeks away, so the horse's trainer must be pretty concerned about the horse losing training.

(For Breeders Cup readers: The frog is a fleshy triangle-shaped pad on the bottom of a horse's foot.)

Sloughed and bruised frogs are a common complaint from horsemen in California on the artificial tracks. The problems could be compounded by the heat of the track in summer months. It is normal for real-world horses to shed the outer layer of their frogs, but racehorses are shod and trimmed so often that their frogs are kept neatly manicured.

Horseshoers at the track have a lot of tricks to help a horse with sore frogs. This photo by our friend Sarah K Andrew was taken during Breeders Cup week at Santa Anita last year.

This horse is wearing a frog-protection plate, sometimes called a mushroom shoe. It can either be an aluminum plate that goes between the shoe and the hoof (some of them look like hockey goalie masks and are called spider plates), or it can be a shoe.

Frogs come in all shapes and sizes. This is Visionaire's frog before the 2008 Kentucky Derby. It probably didn't contact the ground. The frog shape and size of winning horses has never been documented. The width of the frog also determines how the shoe is shaped and how the heels are covered. This shoe is almost an oval; it is probably a hind foot. (Dan Burke/FPD photo)

The same type of shoe or plate is used to relieve pressure on sore heels. The horseshoer may medicate the frog and pack felt or foam rubber under it if the goal is to cushion a sore frog.

Conversely, if the frog is healthy and the goal is to relieve sore heels or a quarter crack, the horseshoer will use the plate to "engage" the frog to bear weight while trimming the heels to relieve weight on them.

This perfectly heart-shaped frog belonged to Gayego before the 2008 Kentucky Derby. Compare it to Visionaire's. Gayego is slated to run in the Sentient Jet Breeders' Cup Sprint. There's no statistical relevance between frog size or shape to speed or performance. Notice how much space there is between the heels of the shoe. (Dan Burke/FPD photo)

There are many reasons a frog can be sore. Infection from thrush or canker is the most common but abrasion also can cause soreness, particularly if a horse has a bulbous, protruding, or fleshy frog. Frogs can and do bleed if they are aggravated enough.

The type of shoe shown here might have been just for training and the horse was reshod with regular plates before training at speed or racing. Standardbreds will race in frog plates, though.

Since the horse spends most of the day in its stall, the trainer would pack the sore hooves with a favorite packing or wrap Animalintex poultice against the bottom of the foot. Turbo tubbing, salt water soaks and spas, foam-lined boots and changing stall bedding are some other treatments that trainers may try to get the frogs back in racing shape.

Away from the dry California climate, a frog could be sore because of excess moisture. In that case, the trainer might medicate with a hoof product containing ingredients from the formaldehyde family to wick moisture, or paint the feet with iodine.

Exercise, even walking, would be considered therapeutic, unless the horse is lame. Circulation can help feet recover and grow.

Protecting soles and frogs and preventing injury will be on the minds of trainers who ship their horses to California for the Breeders Cup. When the European and East Coast trainers see local horses sporting plates like the one in this picture, they will catch on very quickly.