Laminitis In Action: Coffin Bone Rotation Time Lapse Video (International Laminitis Conference Preview)

Laminitis, caught in the act: The foot of a horse suffering from Potomac Horse Fever is recorded as it goes through two processes subsequent to the damage in the foot caused by the disease: the coffin bone appears to be rotating away from the hoof wall at the toe and down at its tip; it is also "sinking" within the foot. These two processes are called rotation and sinking, or sinker syndrome. Many laminitis terms have parallel names in other parts of the world or even within the same country. (Andrew Van Eps video)

(You might have to watch this a few times, and if you have a slow connection, you might need to click on the stop button. Once the video is buffered, it should play smoothly. Watching it in full-screen mode helps.)

What you are seeing is a time-lapse of the radiographic view of a horse going through the process commonly called "rotation". What rotation actually is and which part of the foot is the chicken and which is the egg is perpetually debated. This particular foot is also "sinking" within the hoof capsule.

Andrew Van Eps

The video was created by Andrew Van Eps, BVSc, PhD, MACVSc, DACVIM of the University of Queensland. Dr. Van Eps earned a PhD while he was researching laminitis at the Australian Equine Laminitis Research Unit under Dr Chris Pollitt. Among the insights Dr. Van Eps' PhD research has contributed to the treatment of laminitis is the efficacy of cryotherapy in the prevention of laminitis. He created the video of the Potomac Horse Fever case during a residency at the University of Pennsylvania School of Veterinary Medicine.

At the Sixth International Equine Conference on Laminitis and Diseases of the Foot in West Palm Beach, Florida next month, Dr. Van Eps returns once again to speak. Among his subjects will be suggestions for ways to apply cryotherapy, clinical techniques to prevent support-limb laminitis and his intriguing-sounding lecture, "Lamellar Bioenergetics Studied Using Tissue Microdialysis".


You might be interested in reading "Equine laminitis: cryotherapy reduces the severity of the acute lesion" and "Equine laminitis model: cryotherapy reduces the severity of lesions evaluated seven days after induction with oligofructose" by van Eps and Dr. Pollitt, originally published in 2004 and 2009, respectively, in the Equine Veterinary Journal.

He's probably forgotten all about this video. But to anyone dealing with laminitis, the question of whether or not rotation is inevitable in a given horse remains a paramount concern. How many horses technically experience laminitis and have damaged laminae, but have minor rotation or none at all, and why is there such variation between horses? How many horses have bouts of laminitis that their owners never even notice? Is it still laminitis if no one notices but the farrier, the next time the horse is due to be trimmed or shod?

And what is rotation? Is the deep digital flexor tendon, which attaches on the underside of the coffin bone, actually pulling up and back on the bone as the laminae at the toe loosen their hold on the bone, as we've been taught, and as this video would so nicely illustrate? Or is it the weight of the horse on the compromised structures, compounded by unusual posture, that encourages a combination of those forces to work in concert?

A paper from New Zealand published in this month's (September 2011) Equine Veterinary Journal proposes that the soft tissue structures in the back of a contracted, bar-humped foot make it possible for the palmar processes of the coffin bone to act like a fulcrum around which the coffin bone rotates, and that the tendon has no involvement. (See "The effect of hoof angle variations on dorsal lamellar load in the equine hoof" by Ramsey, Hunter and Nash.)

Lead author Gordon Ramsey was kind enough to send his paper and this section begs to be highlighted; using a Finite Element analysis model, Ramsey calculated forces on the proximal hoof wall at the toe when the heels are raised, as recommended in some laminitis therapy regimen. Extrapolating from that finding, he challenged the mainstream concept of coffin bone rotation in laminitis.

Please note that the author is from the University of Auckland in New Zealand and so uses "lamellae" instead of "laminae" in his text; instead of referring to raising the heels of the foot, he refers to mechanically altering the palmar angle of the coffin bone. It's food for thought whether measurements of heels and coffin bone palmar angles are interchangeable.

A typical laminitis foot, with increased heel growth, which would elevate the palmar angle of the coffin bone as per Ramsey's FE model. According to his calculations, as that palmar angle is intentionally increased in some laminitis treatment protocols, the stress on the proximal (closer to the coronet) laminae inside the hoof wall at the toe would be increased. (University of Nottingham vet school photo)

Ramsey writes:

"The first stage of structural failure in a laminitic hoof involves a stretching of the laminar junction (Pollitt 2007), with rotational displacement occurring subsequently. This seems consistent with a mode of failure that begins at the most loaded proximal part of the lamellae, as predicted by this model, with rotation only occurring after the lamellae have been weakened. 

"It has been proposed that rotational displacement of the distal phalanx, as a sequel to weakening or failure of the laminar junction, is a result of the forces imposed by the deep digital flexor tendon (DDFT) and leverage of the dorsal wall on the ground during breakover (Hood 1999). Experimental results have shown that in laminitic ponies the DDFT force is zero for the first 40% of stance and only approaches a normal value near the end of stance, but that the peak vertical ground reaction force (GRF) is only reduced by 13 percent compared to normal ponies (McGuigan et al 2005). 

"Since the peak lamellar load, predicted by this model to occur at the proximal (not the distal) region of the laminar junction, is more strongly influenced by the GRF than the DDFT force and does not occur during breakover, then this mechanism seems unlikely. 

"An alternative proposed mechanism is that the digital cushion and the region of the attachment of the DDFT are a fulcrum about which the distal phalanx rotates (Coffman et al 1970). As both the DDFT and the digital cushion are soft tissues, it seems unlikely that these could provide sufficient support. 

"However, if the hoof has contracted heels or ingrown bars (Strasser 1997), then these could provide support for the palmar processes to act as the fulcrum for rotation. This could explain why in some hooves the distal phalanx rotates but in other cases, where this fulcrum perhaps does not exist, it only displaces vertically."

Join in the discussion at the Laminitis Conference, October 29-31. The early registration discount ends soon!

 TO  LEARN  MORE

© 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.

Insulin Resistance and Equine Laminitis Research: Australia's Melody De Laat's Academic Elevator Video

Imagine the challenge laid down by the University of Queensland to its graduate researchers: give a three-minute presentation encapsulating your doctoral work. Tell an audience of everyday people from all walks of life why it matters, what it's all about. But keep it short. Can an Australian laminitis researcher describe equine metabolic syndrome in that short amount of time--using only one slide? 3-2-1...talk!

What's your elevator speech?

You have to have one.

If you're an entrepreneur, a job seeker, self-employed or just someone who doesn't want to be left in the dust of this ever-changing world, you have to have to an elevator speech. Once all you needed was a firm handshake, and a spare business card in your wallet for when you met someone. Now you need to be able to tell him or her what you do with your life and why you do it in just a few words.

You need to be able to get the message across that you're special and you're interesting and you're worth knowing/hiring/considering, and you need to say exactly why--all in the time it would take to ride a couple of floors on the elevator of a hotel or office building.

When that elevator door opens, your speech is over.

Yes, you're saying...But then there are academics. And forget engineers. Have you ever asked a researcher or engineer what he or she actually does? I know what you're thinking: Maybe there are some elevators in some coal mines in some Third World countries that would take long enough for a researcher's speech to get to the point--if there is one, that is.

But things are changing. We live in an age of pecha-kucha, the PowerPoint challenge to present your idea in 20 slides that change every 20 seconds, whether you're ready or not. It's the age of the "unconference". And the two-minute video rules, thanks to the way that YouTube has reset our attention spans.

So imagine the challenge laid down by the University of Queensland to its graduate research community: give a three-minute presentation encapsulating your doctoral work. Tell an audience of everyday people from all walks of life why it matters, what it's all about. But keep it short.

And if you get your message across? You could be the winner.

Last year, Melody De Laat answered the UQ Three Minute Thesis competition challenge with a topic related to her thesis: The Investigation of Insulin-Induced Laminitis in Horses. Her research at the Australian Equine Laminitis Research Unit (AELRU) focused on how elevated insulin levels, which occur as a result of insulin resistance, damage the sensitive lamellar (laminar) structures of the horse's foot.

And she had to do it on a huge stage, in an even bigger theater, in front of people who knew nothing about horses' feet, let alone about laminitis or insulin resistance.

“Insulin resistance is an increasingly common problem in horses. The lamellar failure, which is known as laminitis, that results as a consequence of the elevated insulin levels in the body is a painful and debilitating condition,” Melody said confidently.

“By uncovering the mechanisms involved in insulin-induced laminitis it is hoped that we will be able to reduce the morbidity and mortality rates associated with this disease.”
 
The Queensland competition was so well-received that it has been extended to other national and international universities in Australia and beyond. Master of Ceremonies for the event is the award-winning science writer and broadcaster with ABC Science Online, and regular judge on Australian ABC TV's The New Inventors, Bernie Hobbs.

I hope you enjoyed Melody's equivalent of her elevator speech. She advanced to the finals, and there are a lot more people in Australia who know a little bit about laminitis thanks to this competition and Melody's PhD.

And--Oh! Is this your floor?

One of Melody De Laat's research breakthroughs on metabolic laminitis was featured on The Hoof Blog on July 1, 2011. If you'd like to learn more, Melody De Laat will be one of four doctoral and post-doctoral researchers from the Australian Equine Laminitis Research Unit (Simon Collins, Melody De Laat, Brian Hampson and Andrew Van Eps are the team) who will accompany AELRU director Chris Pollitt to speak at the 6th International Equine Conference on Laminitis and Diseases of the Foot in West Palm Beach, Florida October 29-31. 

© 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.

Grayson Laminitis Research Funding Breaks New Ground: Richardson, Pollitt and Van Eps Join Forces for International Support-Limb Laminitis Prevention Study

Today the Grayson Jockey Club Research Foundation announced its selection for the 2011 round of equine research projects that will be funded.

Laminitis research figured prominently in the mix of subjects to be studied. In particular, two studies will receive support from the Lexington, Kentucky-based charitable organization.

The first covers the dreadful form of laminitis that led to the death of 2006 Kentucky Derby winner Barbaro. This will be a multiple-year study; "first year" refers to the funding applied for 2011. Andrew van Eps received his PhD at the University of Queensland in Australia by studying laminitis; his previous contributions have included the first studies of the use of cryotherapy to prevent laminitis.

Here are the Grayson descriptions of the new studies:

Laminar Energy Failure in Supporting-Limb Laminitis

Dr. Andrew Van Eps, University of Queensland--First Year

Andrew Van Eps BVSc, PhD, MACVSc, DACVIM A frequent and disheartening result of injury repair is that the leg opposite the one injured develops laminitis. This is known as supporting-limb laminitis and is what eventually caused Barbaro to be euthanized. Although it is a common occurrence, the mechanisms of the malady have not been established. This project is headed by a young researcher, but the co-investigators are world renowned Drs. Dean Richardson and Chris Pollitt. Professor Chris Pollitt BVSc, PhD The project involves testing the hypothesis that supporting-limb laminitis is a result of reduced blood supply to the connection between hoof and bone (lamellar tissue). Further, that the blood supply in normal circumstances is encouraged by a regular loading and unloading of the legs and hooves (alternating which one is bearing the most weight). Injury to one leg interrupts that alternating pattern. The researchers will test the hypothesis with a state of the art, minimally invasive technique known as tissue mycrodialysis in conjunction with three dimensional computed tomography to develop effective methods of preventing or minimizing lamellar tissue energy failure. Comments in the Research Advisory Committee evaluations included “may well provide immediately applicable strategies to prevent supporting-limb laminitis” and “really nice grant, new idea about a devastating problem.” Dr. Richardson received second-year funding for his ongoing study of laminitis: Dr. Dean Richardson, University of Pennsylvania--Second Year In Vivo Gene Transfer for the Treatment of Laminitis Dean Richardson DVM, DACVS This project seeks to develop a gene therapy approach to prevent laminitis in the contralateral hoof when a horse is being treated for a musculoskeletal injury. This, of course, was what eventually ended the efforts to save Barbaro and is a frequent threat to horses with hoof and leg injuries. The well known research team already has compelling preliminary data which encourages the hypothesis that use of recombinant adeno-associated viruses can be used as vectors to deliver a therapeutic gene (TMP-3) to the lamellar tissues. This is meant to inhibit the damage to the epidermal laminae without disrupting the normal hoof structure. Another completely new study will begin at The Ohio State University, where the mechanism of cryotherapy in averting laminitis will be studied and, hopefully, recreated via pharmacology. Digital Hypothermia in Laminitis: Timing and Signaling Dr. James Belknap, The Ohio State University--First Year The most recent figures from a study involving the USDA and State Veterinary Medical Officers project that at any given time laminitis affects 8 of every 1,000 horses in the United States. Based on the American Horse Council survey that there are 9.5 million horses in the nation, that would indicate 76,000 horses being affected at any given time. Of those affected, the USDA survey found that 4.7% died or were euthanized, or about 3,572 deaths from laminitis annually. The authors of this project report that “an integrated research effort over the last decade has enhanced the current understanding of the pathophysiology of equine sepsis-related laminitis (one of numerous causes of the disease). This has mirrored progression of sepsis research in human medicine by moving from (an earlier) concept . . .to determining that a marked inflammatory injury takes place and is likely to play a prominent role in tissue injury and subsequent failure.” However, there have been persistent failure of systemic therapies for organ/laminar injury in both human and equine medicine. One advantage laminitis presents is that it effects the hoof rather than visceral organs, lending itself to artificial cooling more readily. In a present project funded by the Foundation, digital hypothermia (cooling of the hoof) prior to onset of carbohydrate overload-induced equine sepsis resulted in dramatic decrease in laminar inflammatory signaling. The next goal is to find pharmaceutical therapies which can accomplish the same without the cumbersome aspects of maintaining constant hypothermia to the equine hoof (hooves). Click here to easy-order the poster created with the Michigan State U. Equine Foot Laboratory

 © 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.

University of Queensland's Equine Hospital Keeps Its Head Up Above the Flood

The photos of the devastation on the campus of the University of Queensland are pretty discouraging. As you've probably heard by now, the Brisbane River rose far above its banks and spread through and, in some cases, over the beautiful city of Brisbane in Queensland province in the northeastern corner of Australia.

A core group of veterinarians has created a virtual Noah's Ark for the animals that have been able to reach them...but the tragedy of a true flood is that so many animals are stranded where they are.

A dedicated veterinary team fed, washed, provided medical treatment and comfort to the animals that had been able to make it to their new equine hospital in Gatton. Gatton is the site of the University's new vet school, which only opened on August 6th.

University officials described "horses that had worn down their hooves swimming for up to 30 hours to stay afloat. "

Laminitis researcher and equine specialist Andrew Van Eps BVSc, PhD, MACVSc, DACVIM said that seven horses were brought in for medical treatment for injuries sustained in the floods and his staff members were heading out to farms to treat more horses.

“We have horses in various states of health. Quite a few horses have contracted pneumonia after breathing in flood water while swimming to stay alive,” Dr Van Eps said.

“There is a horse here that was housed in a stable when the flood arrived and had to tread water for about a day to survive.

“We are also are caring for a miniature horse foal that is only a few days old and was orphaned by the floods.”

Besides Van Eps, the equine hospital team includes Dr Susan Keane, Dr Philippe Manchon, Dr Steve Zedler, Dr Claire Underwood, Rebecca Johnson, Kylie Semple, Kate Hertrick,Trent Dawson, David Manchon and Natasha Curlew.

Photos and flood details courtesy of the University of Queensland.

 © 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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Friends at Work: Colten Preston, Australian Farrier Apprentice of the Year

16 December 2009 | Fran Jurga's Hoof Blog at Hoofcare.com

Queensland's Colten Preston has been named Farrier Apprentice of the Year in Australia. Colten is 19, and works for racehorse farrier Mark O'Leary on the Gold Coast. He won a competition for apprentices in Victoria recently, but competition is nothing new to him; he is a serious polocrosse rider and has represented Australia internationally in that sport. Colten is just completing the Australian three-year TAFE training program, which includes college courses, and will work for Mark for one more year. Click here to read the nice article about Colten in today's Courier-Mail from Brisbane; photo courtesy of the Courier-Mail.

© Fran Jurga and Hoofcare Publishing. Please, 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.

The Environmental Hoof: Will Wild Horse Feet Adapt to a Sudden Change in Climate and Terrain? Australian Researchers Switch Brumbies, Observe Hooves

By Fran Jurga and Brian Hampson | November 25, 2008 | www.hoofcare.blogspot.com

Herding horses out of the bush in Australia; photo by Dr. Chris Pollitt

One of the challenges to the paradigm of the wild horse foot as a model for domestic horses has been the criticism that most studies have been done on horses running on arid terrain in the US west. Skeptics have pointed to the platter feet of sand dune horses on the east coast of the USA and variations in herds like the Sable Island ponies that have been limited in genetic input.

Dr. Chris Pollitt was scratching his beard over that one when he launched his Wild Horse Research Project at the University of Queensland in Australia last year. Would it be enough to study generic brumby hooves in the wilds of Queensland? Or would he need to hoof it further afield?

For the past six months, Pollitt and his lead researcher, hoof science PhD candidate Brian Hampson, have indeed been hoofing it, to the wilds of the far Australian outback.

“The aim of this project is to determine if the typical shape of the feral horses’ feet from soft sandy country will develop into the typical shape of feet of the rocky country feral horses when placed on hard rocky country for six months,” writes Hampson. “The reverse case will also be tested.”

“There is currently no evidence that horses’ feet can adapt to suit the terrain they are moving over. If the foot type of the feral horse can change by changing the substrate, then domestic horse’s feet, too, can be presumed to respond to a change in environment. We will demonstrate that sub-optimal foot conformation can be rehabilitated by movement over the right terrain.

“It has been confirmed during the first 12 months of this project that feral horses living on soft sandy country have long and often splayed hooves. Feral horses living on hard rocky country have short, rolled hooves. We will swap six horses from each of these environments for six months to test the effect of the environment on the foot type," he writes.

This foot collected during previous studies from the Waterloo Station bush camp is from a horse that lives on dry rocky ground. (Chris Pollitt research series photo)

This hind foot is typical of the brumby feet from the sandy environments of Australia. (Chris Pollitt research series photo)

He continues: “It is hypothesized that the foot type of the subject horses will switch from the sand model to rocky model and vice versa. We hypothesize that it is the environment that shapes the horse’s foot rather than predetermined genetic factors. It is currently believed that certain breed types are predisposed to certain foot types. By exposing the same horse to two different substrate conditions, the breed factor will be controlled.

“We will use this information to devise a better housing model for the domestic horse. The housing model may include hard substrate and movement stimulation. Our aim is to improve the foot health of the domestic horse.”

Pollitt and Hampson plan to pen an important publication from the study; the results will be presented at scientific conferences in Australia and the USA, and publicized to farriers and horse people during an Australian tour.

You know there had to be some drama and poetry in this study, as you will find if you look beneath the surface of most of Dr. Pollitt’s research. In this case, Pollitt and Hampson will saddle up and ride into the back country. No helicopters for them! They will not only capture their chosen brumbies, but gentle them and then lead them out of the bush.

The chosen environments are the sandy beaches of the Gulf of Carpentaria on the north coast of Queensland, and the rocky desert of Central Australia, 400km southwest of Alice Springs, if you have a map handy. Both locations have feral horse populations in excess of 10,000 horses and have been well studied by Pollitt’s team.

Horses will wear a GPS tracking collar for the six months of their release and a VHF beacon for relocation. Horses' feet will be photographed, radiographed, and their loading pressures and pattern will be assessed using an RS scan pressure plate, both before and after the swap. They will also measure hoof wall growth rate over the six month release period.

The Australian Wild Horse Research Project is unique in that the researchers include not only scientists and students but private citizens who are interested in wild horses or hoof physiology. Donors to the projects are eligible for consideration as mates on the trail, presuming you can brew a decent Billy Tea and waltz beside the billabong. Australia has more wild horses than any other place on earth; in excess of 500,000 horses roam freely, according to Hampson, but he notes that they are subject to periodic sustained drought and culls by "government bodies and private graziers".

Visit wildhorseresearch.com for more information about how you can support the research…or possibly be part of it. We will all certainly benefit from this Outback experiment.

PS I thought this post would be appropriate since today is the premiere of the film Australia in the USA.

© Fran Jurga and Hoofcare Publishing for the Wild Horse Research Project and Dr. Chris Pollitt. No use without permission. Permissions for use elsewhere can be arranged.

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.