Tuesday, November 06, 2012

British Equine Laminitis Research Expands: Why Are Some Horses More at Risk?

New research will look at blood flow to and within the horse's foot to determine why some horses and ponies are pre-disposed to laminitis. The research will be conducted at the Royal Veterinary College in Great Britain. This plastination casting of the blood supply shows the intricate variety of types of blood vessels that serve the foot. A dead horse's foot was injected with plastination material and the foot was treated to remove all evidence of tissue except the plastination. In this model, the blood vessels of the sole were removed to allow a full view inside the foot.  Corrosion casts like this one are sold by Hoofcare Publishing for educational and professional use.
Research announcement:

Great Britain's Royal Veterinary College (RVC) and the WALTHAM® research group are pleased to announce that veterinarian Elizabeth Finding, has joined them and the WALTHAM®-led International Laminitis Consortium to start her PhD on laminitis.

Elizabeth Finding
Finding will continue the essential search into why some horses and ponies have an increased risk of laminitis.

Laminitis is well-recognised as a major global welfare issue; it is a disease causing pain and suffering in those affected. Understanding why some individuals are prone to develop this painful--and potentially fatal--condition has been one of the major goals of the Laminitis Consortium so that targeted preventative measures can be put in place.

Anecdotal information has suggested that there is often an increase in incidence in laminitis following a bout of cold frosty weather. Previous work undertaken at the RVC has suggested that temperature may influence the reactivity of certain blood vessels of the hoof.

As part of her four-year PhD project. Finding will develop novel methods of assessing blood flow so that she can analyze changes associated with diet and season. In addition, she will be comparing innovative markers of blood vessel health between those that are and are not prone to laminitis.

Finding explains: “We hypothesise that ponies prone to laminitis have a dysfunction of the cells lining the blood vessels ("endothelial cells"). This may make them less effective in generating mediators which normally continuously dilate blood vessels and thus protect against the blood vessel constriction. It is thought that abnormal constriction may be initiated by the ingestion of too much rich grass especially under adverse environmental conditions."

The WALTHAM®–initiated International Laminitis Consortium comprises world-leading equine veterinary, nutrition and research experts interested in collaborating on the important topic of laminitis. It includes Dr Nicola Menzies-Gow and Professor Jonathan Elliott of the RVC, Professor Pat Harris of the WALTHAM® Equine Studies Group, and Clare Barfoot of Mars Horsecare UK Ltd.

(End of announcement)

•••••

From Hoofcare and Lameness: Elizabeth Finding is the lead author of a paper published in June 2012 in the American Journal of Veterinary Research (AJVR), "Evaluation of a technique for measurement of flow-mediated vasodilation in healthy ponies".

In that study, Finding and her colleagues tested between-pony and within-pony variations and interobserver and intraobserver agreements of an ultrasound technique for measurement of flow-mediated vasodilation (FMD) in healthy ponies. Testing and evaluation were favorable for using this technique in future research related to laminitis.

Finding is also the author of "Flow-Mediated Vasodilation in Healthy Ponies", published in the Journal of Veterinary Internal Medicine.

Click for Equine Distal Limb current pricing and full ordering information


© Fran Jurga and Hoofcare Publishing; Fran Jurga's Hoof Blog is a between-issues news service for subscribers to Hoofcare and Lameness Journal. Please, no use without permission. You only need to ask. 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.  
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Disclosure of Material Connection: I have not received any direct compensation for writing this post. I have no material connection to the brands, products, or services that I have mentioned, other than Hoofcare Publishing. I am disclosing this in accordance with the Federal Trade Commission’s 16 CFR, Part 255: Guides Concerning the Use of Endorsements and Testimonials in Advertising.

Sunday, October 28, 2012

New Zealand Farrier Stuart Muir Joins Rood and Riddle Equine Hospital Podiatry Center in Kentucky

New Zealand farrier Stuart Muir is now in the USA working at the Rood and Riddle Equine Hospital Podiatry Center in Lexington, Kentucky (image by Fran Jurga © Hoofcare Publishing)
New Zealand farrier Stuart Muir has crossed the Pacific and joined the staff at Rood and Riddle Equine Hospital's innovative Podiatry Center in Lexington, Kentucky.

Muir has been working at the clinic for about six months, but this weekend he took the stage at his first farrier-vet seminar with podiatry center director Scott Morrison DVM. The team traveled to New York to share their expertise at the Equine Clinic at Oakencroft near Albany. The clinic hosts a vet-farrier podiatry seminar each October and invited Morrison back for the second year in a row.

Muir is a native of Christchurch, on the south island of New Zealand, and a 14-year veteran of the farrier profession. In New Zealand, he shod sport and race horses; he is a rider and had taken up Western riding before he and his wife made the decision to move.

How do you prepare for a high-profile job like staff farrier at Rood and Riddle? Muir is a certified farrier through the New Zealand national system and said that, like so many others, he acquired the skills needed for his position at Rood and Riddle by independently pursuing ways to further his education. He traveled to Australia to attend farrier education events with icons like Chris Pollitt and Grant Moon, as well as events at home in New Zealand, but in 2010 won a grant from the Equine Research Fund of New Zealand that financed a trip to the United States.

At the Equine Clinic at Oakencroft, farrier Stuart Muir worked on a pair of front shoes that illustrated two different ways to achieve asymmetric collateral ligament support  for the front hooves of a barrel racing horse. And then he nailed them on. (image by Fran Jurga © Hoofcare Publishing)

As part of that trip, Stuart spent a week doing an externship at Rood and Riddle, which was followed by a second externship in 2011. When fellow New Zealand farrier Rodney King left Rood and Riddle to return home, Stuart was looking into what it would take to fill the vacancy.

Stuart and American Jeff Henderson are currently the two farriers who work fulltime for Rood and Riddle Equine Hospital. The Podiatry Center employs five veterinarians, including Dr. Morrison, and numerous technicians with equine podiatry support expertise.


--written by Fran Jurga

If you like what you read on The Hoof Blog, please sign up for the email service at the top right of the page; this insures that you will be sent an email on days when the blog has new articles. 


To learn more:
Gateway page to the New Zealand government definition of a "farrier" and explanation of the national farriery training and certification program there.

New Zealand government horse careers interview on farriery as a career with Stuart Muir 

© Fran Jurga and Hoofcare Publishing; Fran Jurga's Hoof Blog is a between-issues news service for subscribers to Hoofcare and Lameness Journal. Please, no use without permission. You only need to ask. 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.  
Follow Hoofcare + Lameness on Twitter: @HoofcareJournal
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Disclosure of Material Connection: I have not received any direct compensation for writing this post. I have no material connection to the brands, products, or services that I have mentioned, other than Hoofcare Publishing. I am disclosing this in accordance with the Federal Trade Commission’s 16 CFR, Part 255: Guides Concerning the Use of Endorsements and Testimonials in Advertising.

Monday, October 22, 2012

Prepare for Takeoff: Orsini and Grenager Summary of Laminitis Research at California "Equine Limb" Conference


 in Monterey, California on November 2 and 3, 2012.


When the "Equine Limb" conference opens in Monterey, California next weekend, attendees who are interested in learning about the latest equine laminitis research won't have to wonder, "What page are we on?"

Jim Orsini, conference co-director
with Rustin Moore
It's very easy to dive right into the deep end when it comes to covering laminitis research and treatment, and the conference is carefully planned to simulate a 747 jetliner taking off from a busy international airport: it seems physically impossible for it to become airborne, but it does it by acceleration and lift computed at exactly the right equation. Gravity is defied.

Planning a laminitis conference is very similar. And Dr. Jim Orsini of Penn Vet's New Bolton Center and equine practitioner Nora Grenager are the masters of the craft.

These two standard-bearers of the The Laminitis Conference organizing committee are planning a takeoff that would look familiar to air traffic controllers in their towers. They will review recent research thoroughly but quickly. You should buckle your seat because the conference will reach cruising altitude before you know it!

The review of laminitis research begins at the Monterey event's partner conference, the 2011 International Conference on Laminitis and Diseases of the Foot held in West Palm Beach, Florida, last November; the scientific program there centered on the pathophysiology of laminitis. While the California event has expanded to cover a broader spectrum, its heart is still beating with the mission of solving the laminitis puzzle.

Some highlights that Orsini and Grenager will touch on:

Nora Grenager will review laminitis
research from the Florida conference
as a preface to the California event.
First, the difference between sepsis and systemic inflammatory response syndrome (SIRS), two terms often used interchangeably in laminitis lectures. But when you hear the word sepsis, does it suggest something like a "septic joint", an overwhelming bacterial infection? How does sepsis factor into laminitis? Semantics? Maybe, but it is critical to understanding the new research.

The 2004 Presidential election may have come down to "Florida, Florida, Florida," but the laminitis conference attendees left chanting, "Inflammation, inflammation, inflammation".

But what about the endocrinopathic form of laminitis? Equine metabolic syndrome and Cushing's disease (PPID) research is burgeoning, along with the role of hyperinsulemia (HI). Insulin levels are being re-evaluated as sirens to all sorts of equine health conditions, large and small.  How exactly does hyperinsulemia cause a horse to develop laminitis?

For that answer, researchers looked directly at how insulin functions (or doesn't) in the foot. The role of insulin-like growth factor (IGF) is a critical area of research, since it is possible that insulin is working through a different mechanism in the equine foot's vasculature than it does in the rest of the body.

Can you hear a second chant rising in the background? "IGF, IGF, IGF!"

Laminitis related to hyperinsulemia is the slow, insidious form of the disease, and the one most commonly seen in our horses. The obesity that accompanies it is reversible, and the predisposition of some breeds to hyperinsulemia mean that it is becoming clearer that early identification and therapy for horses at risk must be a priority in the field.

In their abstract, the authors wrote, "Even in horses with no history of lameness, there is a pattern of abnormal hoof growth that is related to HI: abnormal growth rings in the external hoof wall, separation of the wall at the white line, and seedy toe, often with small areas of hemorrhage within the abnormal white line area. This damage is cumulative and at some point culminates in acute laminitis if not properly addressed with diet, exercise, and medication where necessary to normalize blood insulin concentrations."

Support limb laminitis will also be reviewed, and new information on the distinct form of the disease known as "traumatic laminitis", which researchers at Dr. Chris Pollitt's Australian Equine Laminitis Research Unit have outlined. Researcher Brian Hampson PhD discovered that wild horses on arid terrain suffer concussive and/or compressive laminar pathology. Is this laminitis, per se? Much more research on traumatic laminitis needs to be done, but you'll hear about the first phases of this exciting concept.

"Feral horses have little option but to keep moving and either adapt or make do the best they can if they are to survive. In a domesticated horse, comparable changes typically are accompanied by chronic lameness or stiffness, and are incompatible with optimal performance."

That statement in itself is food for thought. While Hampson and Pollitt have cast some doubt on the suitability of the wild horse foot as the ideal equine digit, it seems that there may be deep and profound lessons that can be learned from our domestic horses' wild brethren.

And that, in itself, is just one of the vistas you'll be able to see from the thought clouds of this world-class conference. Distal limb lameness and imaging have been added to the program this year, as the conference's horizons expand over the curvature of the distal limb planet.

If you haven't already reserved your spot at the conference, please do it now. Much more information and a full speaker program is online at www.laminitisconference.com.


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Disclosure of Material Connection: I have not received any direct compensation for writing this post. I have no material connection to the brands, products, or services that I have mentioned, other than Hoofcare Publishing. I am disclosing this in accordance with the Federal Trade Commission’s 16 CFR, Part 255: Guides Concerning the Use of Endorsements and Testimonials in Advertising.

Saturday, October 20, 2012

British Barefoot Hoof Tape Controversy Escalates: Advocate Pledges Legal Assault on Farriers Registration Act, Council, and Illegal Farriery Charges

A hoof trimmer at work on a horse. Both hoof trimmers and farriers wear aprons, use hoof stands, and  carry knives, nippers and rasps. How much of the similarity ends there may be determined in court. (Photo by Jean-Pierre)

It’s just part of the horse. A few cubic inches at the end of a leg. But who’s in charge of it, anyway?

In Great Britain, the furor surrounding sovereignty over the hoof just won’t go away. In other parts of the world, including the United States, it may seem like it’s much ado about nothing. But when decisions and news about the definition of a profession are made half a world away, it potentially makes a difference everywhere.

In September, the Hoof Blog reported on a court case in Great Britain in which a hoof trimmer pleaded guilty to illegal farriery because he applied what is commonly called “hoof casting tape” to a client’s lame horse.

Hoof injuries are often treated with hoof
casting tape. (Extension.org photo)
Information for that article was provided in the form of a press release from the Farriers Registration Council, a statutory body in Great Britain with powers to inititiate legal processes against non-farriers; the agency is charged with enforcing the Farriers Registration Act, an Act of Parliament passed in 1975 which defines farriery for that nation and prohibits anyone but a registered farrier or veterinarian from shoeing a horse.

Read the previous Hoof Blog article about the barefoot trimmer's hoof tape prosecution.

How do you get to be a farrier in Great Britain? It's not easy. A four-year-and-two-months apprenticeship and examination are required; farrier education and training are the province of a separate body, the Worshipful Company of Farriers (WCF). Only "Approved Training Farriers" are allowed to have apprentices.

For a long time, the FRC’s dominion over the hoof was more or less unchallenged, except by the occasional unregistered farrier plying the trade on the sly. When barefoot trimming came along, the new professionals were tolerated outside the dominion of both the FRC and WCF because farriery's definition in the UK describes it as  ‘any work in connection with the preparation or treatment of the foot of a horse for the immediate reception of a shoe thereon, the fitting by nailing or otherwise of a shoe to the foot or the finishing off of such work to the foot’.

Hoof tape is a popular hoofcare product in the United States and is sold in different forms by different manufactures. The  British campaign does not specify particular brands or applications but rather cites the use of the product on hooves. (Hoof Blog archives graphic from first report on hoof tape prosecution)

No shoe? No problem. At least that is how the barefoot trimmers viewed the law. They were free to conduct business. In a move that most freethinking Americans would consider evidence of a nanny state, the British government agency LANTRA set up a government body to develop training and testing systems to manage the new trade.

But perhaps everything wasn’t spelled out as clearly as it needed to be. The professional standards for barefoot hoof trimming don't mention the use of shoes or the application of support materials.

Is hoof tape a shoe? The FRC seemed to think so, and in the recent court case, the legal judgment concurred. But the tempest in the British hoof tape teapot might be a bellwether for legal tests of farriery around the world.

The hoof trimmer pleaded guilty to illegal farriery and was charged a fine and court costs. But he wasn’t the first: Less than a month before, another hoof trimmer was charged for using hoof tape. Her charges were dropped.

Horse owner and hoof tape
advocate, Annette Mercer
But one of her clients doesn’t want to let it drop. A horse owner named Annette Mercer from Bath, England has established a legal defense fund for barefoot trimmers who run foul of the definition of farriery; she has published a manifesto to topple the power of the Farrier Registration Council and re-write the Farriers Registration Act.

Annette Mercer credits the work of her hoof trimmer and the effects of wearing hoof tape for the remarkable recovery of her horses from a variety of hoof-related complaints.

The website "Fighting for the Barefoot Horse" is Mercer's call to arms with three aims. Her web site tells us: (quoted from web site)

  • The immediate aim is to put a stop to the FRC (Farriers’ Registration Council)’s prosecution/persecution of barefoot/podiatry practitioners, such as Lindsay Cotterell and Tom Bowyer;
  • The medium term aim is for the community of barefoot owners and practitioners to take up the LANTRA challenge to put in place a nationally recognised program of training and qualifications for barefoot care.
  • And finally, we would like the current legislation that governs the definition of what is a shoe – The Farriers (Registration) (Amendment) Act 1977-- to be repealed and replaced with something that recognizes both our growing understanding of the miracle of horses’ hooves, and also the technological advances in products to support the barefoot horse. The flexible hoof wrap, featured in current FRC prosecutions, is just one example of such products.
"We don’t believe in telling anyone they must take their horses’ shoes off and allow them to go barefoot, although it’s clearly worked for us. But nor do we accept the right of the FRC, a trade body that represents the interests of farriers who shoe horses, to tell us that we can’t use a barefoot hoof care provider to care for our horses and to threaten us with prosecution if we do," Mercer writes on her new website.

Attorney Lawrie has pledged to
defend the next hoof trimmer
charged with illegal farriery.
(web site photo)
The “Fighting for the Barefoot Horse” campaign has pledged 15,000 British pounds (US $24,000 ) to defend the next trimmer who is accused of performing illegal farriery by applying hoof tape. The money is pledged to the research expenses of Ian Lawrie QC, described as a “top UK lawyer”, who has agreed to represent the barefoot faction on a pro bono basis, minus those research fees, apparently.

Mercer writes that the privileges of the Farriers Registration Act "prevent the progression of the barefoot movement in the UK and mean that owners like us are forced to employ farriers to look after our horses' hooves. It is a blatant case of bullying by the FRC; the big boys thinking that because they have money behind them they can abuse their statutory powers and push people into doing whatever they want."

In reality the FRC is not in business just to ruin a barefoot trimmer's day. The most recent case before the FRC’s Disciplinary Committee was to chastise one of its own. A farrier performed what sounds like excavation of an abscess in a horse's sole, but the horse became more lame. When the vet was finally called, the horse was diagnosed with quittor on its pastern, and the farrier was prosecuted for failing to recognize that condition, as well as failure to seek veterinary treatment of the lameness. Judgment will be forthcoming.

In another case, a farrier convicted in a court of law for drug possession had his professional status reviewed by the FRC. He was not "struck off the register"--banned from working as a farrier--but his judgment will also be announced at a later date.

It sounds like the British governing bodies need to define one of two things--or more: What's the definition of a barefoot horse? Or, what's the definition of a shoe? Must a barefoot horse be literally bare? Is alternative hoof support--whether removable or fixed--a shoe by another name?

In Germany, the situation was even worse, since farriery there was defined with the inclusion of applying steel shoes. Alternative farriers started businesses using plastic shoes, glue-on shoes and hoof boots, as well as barefoot hoofcare, and were not required to go through long apprenticeships the way that farriers did as long as they didn't use steel. An effort to reform farriery there failed to combine the two professions, after proposing that everyone learn to both shoe with steel and use alternate materials. The barefoot faction simply refused, saying that they should not be forced to learn a skill they wouldn't use.

Barefoot hoof trimming worldwide has evolved so that a percentage of horses are being "equipped" with alternative materials like hoof tape, or wearing hoof boots, which are removable hoof protection and could be technically argued to be a type of shoe in a courtroom context.

From far across the Atlantic, it looks like the British missed an opportunity to define barefoot trimming as an adjunct form of farriery so the trimmers would be protected by law instead of being victims of it.

The word "barefoot" may come back to haunt the new profession, just as the word "shoe" pigeon-holes the farriers. Unfortunately for horses and the advancement of hoof science, the British problem continues to divide people into camps and hold back progress, rather than carry hoofcare forward.

If you asked anyone from either camp, they would say that that is what they want: progress in understanding the foot and improving the care they can offer. But, the way things are set up, each camp wants it on their terms.

And if you ask anyone who's been there, decisions made in court rarely clear the air and usually benefit the lawyers involved more than the people on either side who will be affected by even the most well-intentioned efforts to interpret, reform or create a law.


To learn more:
Original article: Hoof Casting Tape: A Shoe By Another Name? Non-Farrier Hoofcare Practitioner Pleads Guilty to Illegal Farriery in Great Britain
Read the National Occupational Standards for Farriery in Great Britain
Click here for full ordering details for Professor Denoix's indispensable reference book.

© Fran Jurga and Hoofcare Publishing; Fran Jurga's Hoof Blog is a between-issues news service for subscribers to Hoofcare and Lameness Journal. Please, no use without permission. You only need to ask. 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.  
Follow Hoofcare + Lameness on Twitter: @HoofcareJournal
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Disclosure of Material Connection: I have not received any direct compensation for writing this post. I have no material connection to the brands, products, or services that I have mentioned, other than Hoofcare Publishing. I am disclosing this in accordance with the Federal Trade Commission’s 16 CFR, Part 255: Guides Concerning the Use of Endorsements and Testimonials in Advertising.

Thursday, October 18, 2012

British Pilots Abort Flight, Alert Firefighters When Burning Smell Noticed

The firefighting unit responded to pilots' notification of a burning smell in their aircraft at a British airport tonight. (Paul Hamilton photo)

A British flight was aborted earlier today when pilots returned to the terminal after they both said they identified a burning smell.

The pilot and co-pilot of a flight from the island of St Mary's in the Isles of Scilly to Newquay in Cornwall were alarmed, according to a report in the newspaper, This Is Cornwall.

Airport firefighter Kevin James said: "It was lined up ready to take off when one pilot said to the other 'can you smell burning?' to which the co-pilot apparently replied 'I was wondering whether you were going to say anything in case it was just me'."

Control tower personnel alerted the firefighting unit.

"We were told of a burning smell in the cabin," said Mr James. "While other flights were put on hold we dashed to the fire engine and put on our kit."I had a chat with the captain and disembarked all the passengers.

"One of the last to get off looked at the first officer and said, 'I think it might be me'."

Mr. James disclosed that the person who spoke up was a farrier from the mainland who had been shoeing horses on the island all day.

Sometimes farriers can't avoid taking their work with them at the end of the day.
(Photo credit: Hugh Hume)

© Fran Jurga and Hoofcare Publishing; Fran Jurga's Hoof Blog is a between-issues news service for subscribers to Hoofcare and Lameness Journal. Please, no use without permission. You only need to ask. 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.  
Follow Hoofcare + Lameness on Twitter: @HoofcareJournal
Read this blog's headlines on the Hoofcare + Lameness Facebook Page
 
Disclosure of Material Connection: I have not received any direct compensation for writing this post. I have no material connection to the brands, products, or services that I have mentioned, other than Hoofcare Publishing. I am disclosing this in accordance with the Federal Trade Commission’s 16 CFR, Part 255: Guides Concerning the Use of Endorsements and Testimonials in Advertising.

Friday, October 12, 2012

Hallmarq Standing MRI: Hoof Conformation from the Inside Out

 
This sponsored blog post is the latest in a series produced in partnership with Hallmarq Veterinary Imaging. Thanks to Hallmarq for their support of The Hoof Blog. This video explains the process known as "Standing MRI" of the equine foot using a Hallmarq system. The units are in use around the world.

Which came first: the chicken or the egg? 
Forget everything you “know” or think you know, about the relationship between foot shape and lameness. What matters in this age of evidence-based veterinary medicine is 1) what can be demonstrated and measured; 2) reliably repeating what was demonstrated; and 3) documenting the data of the measures.

If some hoof research makes you yawn and seems to be proving what is already obvious to you, remember that building a better tower of knowledge means that we know we can count on the blocks at the bottom of the tower. They must be proven before we can move on.

Hoof science is shy a few blocks. The tower is still on the drawing board. In order to document what you "know"via the scientific process, it is necessary to approach it from different angles so that it can be measured.

The deep digital flexor tendon (DDFT) is the most common site of damage in the foot identified by standing MRI scanning of sport horses. As you know, this tendon runs down the leg and attaches to the bottom of the coffin bone (P3). The three arrows added to this scan are directing the eye to the portion of the DDFT which, in this Irish horse, has a lesion that looks like a split. Normally tendon would be solid black. The recent study in England looked at a group of horses with similar injuries of the DDFT and measured for similarities in the conformation of foot structures. (Photo courtesy of Troytown Equine Hospital, Co. Kildare, Ireland.)
When researchers at Great Britain’s Royal Veterinary College wanted to get to the bottom of this age-old conformation to lameness relativity issue, they used Hallmarq standing MRI images to collect data that could be measured. The group of investigators worked under the direction of Renate Weller Dr Med.Vet, PhD, MRCVS, FHEA, senior lecturer in diagnostic imaging and locomotor biomechanics, at the RVC's Structure and Motion Laboratory.

Tim Mair, BVSc, PhD, DEIM, DESTS, DipECEIM, MRVCS is an author of the paper and a partner in England's Bell Equine Veterinary Clinic, where Hallmarq Standing MRI scans were sourced by Hallmarq's Nick Bolas. Also from the private sector, and a recent RVC graduate, Jonathon Dixon BVetMed MRCVS of Rainbow Equine Clinic was involved with the study.

The premise of the study is an inside-out refinement of hoof confomration. Instead of measuring the circumference of the hoof capsule and the contour of the coronet, they measured or calculated characteristics of the structures inside the foot. The availability of real-world lameness cases' standing MRI scans meant that the researchers had the luxury of a library of almost 200 images of injured or lame feet that met the study's criteria.

The MRI would have been originally made to assist in a definitive diagnosis on a lame horse. The clinician noted that the MRI showed a lesion in the deep digital flexor tendon or injury to the navicular bone, etc.

The researchers from the Royal Veterinary College undertook the project of evaluating these standing MRI scans not in the context of a single lame horse, but in the hopes that they would find other similarities in the feet of horses that had received the same diagnosis.

Once again: don’t assume anything, but see what the MRIs had to say.

If you overlaid a dozen images of the same type of injury from a dozen horses’ hooves, would the hoof capsules line up and show similar characteristics?

The researchers found that there indeed was similarity in the measurements of feet with the same diagnosed injuries.

What type of horses and lameness?

The mean age of horses in the study was between ten and eleven years; the average grade of lameness was approximately a “3” on a scale of 1 to 10. Breeds included 37 Warmbloods, 51 Thoroughbreds and Thoroughbred crosses, 22 Irish sport horses, 15 Irish draft horses and Irish draft crosses, 11 Cobs and 43 horses of other various breeds.

The horses had been diagnosed with many types of injuries, including lesions of their deep digital flexor tendon (DDFT), navicular bone (NB), collateral ligaments of the distal interphalangeal joints and
25 other structures.

What was measured? C, sole angle; D, toe angle; H, heel angle; N, deep digital flexor tendon angle; PL1, plumb line 1;  PL2, plumb line 2;  MA1, proximal moment arm; MA2, distal moment arm; SI, distal phalanx length; LC, toe length.

Sole angle


Sole angle is a relatively new term in the lexicon of foot anatomy. It is not the angle formed where the sole meets the wall, as documented in some studies. Its number is not describing the sole at all, in fact, rather the concavity of the coffin bone.

Dr. Weller took the time to explain it for Hoof Blog readers as the concave sole surface of the coffin bone to horizontal angle. Check the diagram to see the point on the mid-sagittal MRI scan where this angle is measured.

Dr Weller explained: "The issue we have in practice is that the sole angle we measure on radiographs does not correspond to the angle at which the DDFT actually attaches, but (rather we measure) the lateral and medial coffin bone borders.

"This (angle of the coffin bone) can be taken as an approximation at best, since the concavity of the coffin bone differs between horses. So some may have little concavity and in those horses the radiographic measurement will correspond quite well to the insertion angle of the DDFT, (however) some horses may have (a) very concave coffin bone and in these the radiographic measurements will not represent the DDFT insertion angle.

"The reason we care about this angle is that it is strongly related to the strain the DDFT experiences and hence the pressure this tendon exerts on the navicular bone," she concluded.

Measurement results

  • A larger sole angle was associated with combined deep digital flexor tendon (DDFT) and navicular bone (NB) lesions, but not with NB lesions alone.
  • A more acute angle of the DDFT around the NB was associated with DDFT and NB lesions.
  • A lower heel height index was linked with DDFT injury.
  • The larger the sole angle, the smaller the likelihood of a DDFT or NB lesion.
  • Measurements of the feet in the study contradicted findings of other studies.

Why is this study important?

Taking measurements from diagnostic images is not a new idea, so why is this study newsworthy? 
Previous studies have shown that certain conformational traits--sole angle in particular--increase forces acting on the DDFT and NB in sound horses. This study supports these findings by showing that conformational parameters are associated with DDFT and NB lesions in lame horses.

Standing MRI is done with the horse
bearing weight on the injured limb
The researchers noted that while this study shows an association between certain conformation parameters and foot lesions, foot conformation cannot be identified as causative factor of lameness. "Foot conformation may change as a consequence of lameness," they concluded.

Which brings us back to the chicken and the egg.

Future studies at the RVC will focus on dynamic conformation by investigating foot-surface interaction in lame versus sound horses, which may eventually open a preventative and/or therapeutic window for horses in the process of developing specific lesions within the foot.

Relevance of this study


The study's findings emphasize the deep digital flexor tendon's influence on the conformation of the foot and that it plays a leading role in many foot lameness problems. The DDFT's angle within the foot and the relative concavity of the distal phalanx (P3) (as measured by sole angle) may become routinely documented in the future.

Studies like this one are changing the way that foot structures are evaluated and measured. Standing MRI scanning provided three-dimensional evaluation of the foot, expanding the diagnostic field for the most precise possible examination of foot tissues and for the most accurate measurement protocols for scientific relevance. 

But Weller’s team’s emerging protocols for evidence-based hoof evaluation provide the sport horse and racing worlds with a basic building block that could one day be used on important studies to answer questions on equine welfare, prevent pain and increase a horse’s useful years. The hoof is one of the last frontiers of equine science, and the Royal Veterinary College is dedicated to learning more about it.

Research can’t be any more relevant than that.

To read the full paper: Kate Holroyd, Jonathan J. Dixon, Tim Mair, Nick Bolas, David M. Bolt, Frederic David and Renate Weller; Foot conformation in lame horses with different foot lesions diagnosed, published online in The Veterinary Journal, September 2012.

 To learn more about Hallmarq Veterinary Imaging and standing MRI technology for horses:



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