Sue Dyson: More Information on Collateral Ligament Injuries in the Foot Follows Up Paper in Our Journal

This image from the journal article illustrates the telltale bump on the coronet that indicates a collateral ligament injury. However, Dr. Dyson warns that such visible signs are evident only in a percentage of cases. She recommends scintigraphy or MRI for identifying ligament damage in horses that illustrate specific lameness behavior characteristics.

Sue Dyson's article "Desmitis of the Collateral Ligaments of the Distal Interphalangeal Joint" was very well-received when it was published in Hoofcare & Lameness #79. While it is often difficult to definitely prove that collateral ligament (CL) injury is the sole cause of lameness, particularly in sport horses with degenerative joints and possible multiple foot problems, the good news is that horses do tend to recover from CL injuries.

Recently Sue shared with me her newest paper, which is a retrospective of more than 200 horses that had been diagnosed with lameness related to collateral ligament injury in the foot.

Among the many key points were that there was rarely any outwardly visible sign of injury not could the injury site be palpated or manipulated to induce or replcate the lameness. Trotting in circles on a hard surface was the ideal test. Only occasionally was heat or swelling present. While the injury has now become a common diagnosis for hardworking event horses and jumpers, it may be common in other sports as well.

The horses fell into three groups for comparative study of their diagnostic images, histories, and follow-up, when available.

In a group of 109 selected horses studied for comparison, the medial ligament (73%) was more damaged than the lateral (27%) one; the damage to the ligament was visible on MRIs of all 109 horses. One third of the horses from that sector of the study returned to work. These horses were identified as having lameness caused directly by injury to the ligament, and no other known cause of lameness.

A second group of horses had collateral ligament injury as one of multiple lameness disorders affecting the horse's soundness; these horses had a much poorer prognosis.

A third, smaller group of horses had problems with the ligaments at the point of origin or insertion, but 55% returned to full athletic function.

One of the points made in the paper that is very interesting is the higher incidence of bilateral collateral ligament injury, although the medial is still the more severely affected, in most cases.
A telltale sign of common CL injury in the foot is when the horse is more lame on the outside leg when trotted in a circle on a hard surface.

Whenever possible, Hoofcare & Lameness tries to keep readers up to date with newer research by our authors.

Sue Dyson is a consulting editor of Hoofcare and Lameness and generously shares her articles and photos and cases with us. In Hoofcare 80, she addresses the dilemma of lameness examinations on horses with multiple limb lameness, and suggests guidelines for sorting out horses that are two-legged, three-legged and even all-legged lame.

She is also co-author, with Mike Ross of UPenn, of the reference book Diagnosis and Management of Lameness in the Horse, sold through Hoofcare Publishing.

For more information, see "Desmitis of the Collateral Ligaments of the Distal Interphalangeal Joint" by Sue Dyson MA, VetMB, PhD, DEO, FRCVS in Hoofcare and Lameness Journal, issue #79
and
"Collateral Desmitis of the Distal Interphalangeal Joint in 233 Horses (January 2001 –July 2006)" published in the Proceedings of the 11th North Carolina State Medical Association, 2006

Plastinate: A Funny Name for a Fascinating View of Soft Tissue, Horn, and Bone

If you have visited a Hoofcare and Lameness trade show booth at any of the conferences this winter, chances are that you saw our display of plastinated samples of hoof tissue. If you haven't been to our booth, perhaps you have been to the highly successful (and somewhat controversial) museum exhibit called "Body Worlds," which also uses the plastination process to preserve body tissue. While we can be forgiven for studying closeup hoof tissue, the jury is still out on the ethics of human tissue manipulation.

We are working on bringing Dr. Christoph von Horst of Germany to the USA to share his delicate and precise representations of the hoof. Best guess is that he will be in Palm Beach for the laminitis conference in November.

In the meantime, Hoofcare and Lameness will facilitate orders for Dr von Horst. Each tissue sample is, of course, life size and sandwiched in inch thick Lucite. The sample becomes a living study object but it also is a work of art, and the play of light through the hoof tisue is dazzling.

One visitor to our booth at the AAEP convention was so enchanted that he offered to buy the entire display!

Each sample is treated to resist light damage and will not fade. The cost on most is around $200 including air shipment from Germany. I will try to mount some more images to share them with you, but please contact Hoofcare and Lameness if you are looking for a unique gift, award, trophy, or a real treat for your own study of the hoof. Navicular damage and P3 rotation samples are available but sometimes are in great demand and have a longer lead time.

What's the Antithesis of Natural Horsemanship? Meet No Horsemanship: Robotic Horse Training on a Sanitized Track

Call this the round pen backlash. Or high technology's answer to the average human's inability to train a horse. Several sources on the web have pointed me to a web site for what appears to be an Eastern European group that is promoting horse training systems that remove the influence of humans from the conditioning process.

Did you ever wonder what Disney World did with ride parts when they go through periodic renovations?

Kurt Equine Systems of course would appeal to a trainer who has more horses than exercise riders. Or someone who needs to condition multiple endurance horses but simply does not have the time to get them all ridden. There are also problems with weather and reliable help and many other variables in training that can make you dream of a "system" that would get all the horses moving and know when to quit.

Watching this video, I thought I was in a bizarre futuristic equine science fiction film. Dr Who goes to the racetrack? But the racetrack has been sanitized, and the only people in sight are in the control room--or are those robots, too?

The web site promo doesn't give many details; it tells us that these systems work for either horses or camels, so that is a broad hint to me that this prototype has been installed in the Middle East, possibly in Qatar, Saudi or The Emirates, although I think if it was in the UAE I would have heard about it. Someone would have called me from the World Cup back in March and said, "You MUST see this!"

I present this to you only as a wonderment. No comments, just wonderment. I knew when I posted the video of the Seawalker system for hoof rehab that someone would have to top it. And this is way over the top!

Link to individual video clips of horse monorail and robotic training systems.

For the time being, I think exercise riders still have job security but if Todd Pletcher's string gets much larger...

Pergolide Cleared for Equine Veterinary Use by FDA

This announcement just in from the FDA:

May 11, 2007

CVM Working to Address Concerns about Supplies of Pergolide for Horses

The Center for Veterinary Medicine (CVM) is aware that veterinarians and horse owners are concerned about the issuance of an FDA Public Health Advisory (PHA), www.fda.gov/cder/drug/advisory/pergolide.htm, detailing the removal of pergolide products from the market. Pergolide, a drug used to manage the signs and symptoms of Parkinson’s disease in humans, is being removed from the market due to concerns about cardiac side effects.

CVM recognizes that veterinarians are prescribing pergolide for the treatment of Cushing’s Syndrome in horses. Veterinarians have been prescribing the drug under the provisions of the Animal Medicinal Drug Use Clarification Act which allows veterinary practitioners to prescribe approved human drugs for “extralabel” use in animals.

FDA is working with the sponsors of the approved products and all other interested parties to ensure that pergolide remains available to treat Cushing’s Syndrome in horses until a new animal drug application is approved for that use. This includes trying to make the approved product available through veterinary distribution channels and exercising enforcement discretion as appropriate over the pharmacy compounding of pergolide. Bulk substance used for pharmacy compounding should be labeled for “animal use only.” All pharmacy compounding must be done under a valid veterinary prescription to treat an affected horse.

Although the sponsor has stopped marketing pergolide for human use, CVM will also work with sponsors who are interested in seeking approval of a new animal drug application for the use of pergolide to treat Cushing’s Syndrome in horses.

For more information, contact Christopher Melluso, DVM, at Christopher.Melluso@fda.hhs.gov or (240) 276-9065.

New Lameness Treatments: IRAP™ Therapy

One of several new high-tech treatments for equine lameness is the creation of an enriched serum injection for horses with potential joint damage. "IRAP" is not a new hip-hop group; it's a therapy that has quickly made its own place at the table of equine therapy, especially for sport horses and racehorses whose owners expect a return to the previous level of soundness and performance...in the shortest possible length of time.

Interleukin-1 Receptor Antagonist Protein (IRAP™) therapy works like this: the veterinarian, often a surgeon or lameness specialist, injects a horse’s affected joint with serum that contains anti-inflammatory proteins that block the harmful effects of Interleukin-1 (IL-1), an inflammatory cytokine that has been shown to accelerate destruction of cartilage during osteoarthritis. (A cytokine is a chemical secreted by the immune system to attack infections and damaged or dying cells.)

What makes the process a little complicated is that Interleukin-1 (IL-1) is a quite normal part of the horse's inflammatory response but it can sometimes be detrimental to a horse's joints and accelerate damage to cartilage there. IRAP™ creates a barrier that prevents IL-1 from having its damaging effect.

Since the serum sample is derived from the horse’s own blood, there is minimal risk of an adverse reaction. The incubated serum also does not contain any drugs.

The treatment process consists of drawing a blood sample using a special syringe containing glass beads. The blood is incubated for 24 hours and a centrifuge separates the serum from the red blood cells. The serum, now enriched with Interleukin-1 receptor antagonist protein, is divided into three or four doses. The horse receives one dose injected into the affected joint once weekly for three to five weeks.

A quick check around the web found that quite a few vet clinics are promoting IRAP therapy. Here are some comments from veterinarians:

Dr. Laura Werner of The Equine Center in San Luis Obispo, California: "The reason IRAP is so exciting is its potential for a long-term effect on battling osteoarthritis. Whereas some of the therapies might only have short-term effect, IRAP has the potential to stop the cartilage matrix from being degraded and increase healing. IRAP has the ability to stop the inflammation cycle and bring comfort to your horse. The research on IRAP is ongoing but the results have been very encouraging."

Dr. Laurie Tyrrell of Virginia Equine Imaging: "IRAP can also be used as maintenance therapy throughout a competition season to reduce the amount of steroid use. IRAP therapy is not for every horse. There are some factors that make a horse a less successful candidate; however the therapy shows great promise for horses that have become refractory to traditional management of osteoarthritis, as well as offering an alternative therapy for those worried about excessive use of corticosteroids."

According to the web site of Steinbeck Country Equine Clinic in Salinas, California: "Coffin joints and stifles that don’t respond well to steroid injections seem to be the most popular condition to treat (with IRAP therapy). Reactions are uncommon largely due to the fact that it is the patient’s own serum."

IRAP is one of the many therapies and treatments that will be on the program of the 4th International Equine Conference on Laminitis and Diseases of the Foot to be held in West Palm Beach, Florida, from November 2-4.

Pergolide Update: Resource Blog Launched for Horse Owners Concerned about Drug Ban

Above: a horse shows common signs of Cushings disease, including the telltale long coat that does not shed. Horse owners report a rapid improvement of the appearance of horses when they receive pergolide as a medication for Cushings disease. Photo courtesy of our friend, Dr. Christian Bingold.

A proactive horse owner in Pennsylvania has pleaded her case for U.S. Food and Drug Administration (FDA) release of the Parkinson's disease drug "pergolide" for equine veterinary use by enlisting the power of the broadcast media. Horseowner Judy Amick and her veterinarian were interviewed for a story that ran on the 5:00 news yesterday on WJAC-TV6, the NBC affiliate in Johnstown, Pennsylvania.

Pergolide is widely used to medicate horses suffering with Cushings disease. Many people credit oral pergolide medication with controlling their horses' Cushings symptoms, especially the periodic low-grade laminitis that is a common side effect of the disease.

Recently, pergolide was removed from the US drug market by the FDA because of side effects experienced by human users.

Horse owners say that their horses have no side effects, and that the drug is actually keeping horses alive that would have to be euthanized without the drug.

Click on this link to watch a clip from the segment: http://www.wjactv.com/news/13288711/detail.html?rss=john&psp=news

The withdrawal of pergolide has been a call to arms for Pennsylvania veterinary expert and author Eleanor Kellon VMD. She is the resident medication expert on the 5000-member "Cushings list" discussion group on Yahoo.com. The discussion group helps support owners of horses with Cushings or insulin resistance problems.

To mobilize of horse owners to take action in the pergolide situation, Kellon has launched a blog designed to give details on the drug's political battles, and to give owners resources for letterwriting and petitions.

Click on this link to go to the new blog: http://pergolideaction.blogspot.com/

"This site has been started to keep (people) current on the latest information in the fight to keep pergolide available for our horses," Kellon writes of the new blog. "There is at present no viable alternative to pergolide to control Cushing's Disease (PPID) or to stave off the debilitating, often painful and life-threatening side effects of this disease."

Kellon encourages horse owners to sign the "Save Pergolide" petition, and use the site's links to write to federal and state officials, elected representatives, equine veterinarian associations, state horse councils and groups.