The Modern
Equine Vet www.modernequinevet.com
Vol 5 Issue 12 2015
Headshaker Not a diagnosis you want to make AAEP Meeting: Wound care without the trauma Suspensory ligament branch injury risk Technician Update: Removal of a sequestrum on the proximal tibia
Table of Contents
Cover story:
Headshaking: 4 Not a diagnosis you want to make Cover photo Shutterstock/ Lenkadan
Dermatology
Wound care without the trauma........................................................................................8 Sports Medicine
Risk factors for injury in Swiss horse racing.................................................................13 technician update
Surgical removal of a sequestrum on the proximal tibia...................................17 News
Suspensory ligament branch injury risk in Thoroughbreds..........................................................................3 UC Davis integrates sports medicine for horses....................14 AAEP honors Dr. Nathaniel A. White, others..........................15
advertisers Shanks Veterinary Equipment.................................. 3 CEVA Animal Health.................................................... 5 Avalon Medical............................................................. 7
Merck Animal Health.................................................. 9 Universal Imaging.....................................................11 AAEVT............................................................................16
The Modern
Equine Vet Sales: Matthew Todd • ModernEquineVet@gmail.com Editor: Marie Rosenthal • mrosenthal@percybo.com Art Director: Jennifer Barlow • jbarlow@percybo.com contributing writerS: Paul Basillo • Kathleen Ogle COPY EDITOR: Patty Wall Published by PO Box 935 • Morrisville, PA 19067 Marie Rosenthal and Jennifer Barlow, Publishers percybo media publishing
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Issue 12/2015 | ModernEquineVet.com
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news notes
Suspensory ligament branch injury risk in Thoroughbreds
Photo courtesy of the Equine Veterinary Journal
There is an association between sesmoiditis and suspensory ligament branch changes, and these changes can be found on ultrasound, according to a recent study. There is also a relationship between these conditions and subsequent clinical suspensory ligament branch injury (SLBI), especially when these findings transpire concurrently. This prospective study aimed to investigate the associations among radiographic signs of sesamoiditis, ultrasonographic signs of suspensory ligament branch desmitis and subsequent clinical SLBI.
prevalence of Grade 2–3 suspensory ligament branch change was 18.5% (Observer 1) and 23% (Observer 2). Once adjustments were made for interobserver differences, there was a significant association between Grade 2–5 sesamoiditis and Grade 2–3 suspensory ligament branch injury: 28% of sesamoids with Grade 2–5 sesamoiditis also had Grade 2–3 suspensory ligament branch change of Grade 2–3, compared with 4% of sesamoids considered to be normal. Eight horses developed clinical SLBI, of which 5 had Grade 2-5 sesamoiditis and Grade 2–3 suspensory ligament branch change at initial imaging assessment. When considered separately, both Grade 2–5 sesamoiditis and Grade 2–3 suspensory ligament branch change were significant risk factors for subsequent SLBI. When these happened concurrently, there was a significantly increased risk of clinical SLBI. MeV
Lifting Large Animals Since 1957
Transverse image of subsequent injury of the suspensory ligament branch.
Before commencing training, 50 yearling Thoroughbreds from a single training facility were evaluated. Radiographic changes in sesamoid bones were graded on a scale of 0 to 5: Changes of Grades 2–5 were considered as possibly significant sesamoiditis. Ultrasonographic changes in the forelimb suspensory ligament branches were graded from 0 to 3, with Grades 2–3 considered as possibly significant. Further imaging was performed only if clinical SLBI occurred over the course of the subsequent nine months. The prevalence of Grade 2–5 sesamoiditis in initial radiographs was 20.5% (Observer 1) and 23% (Observer 2) of all 200 sesamoid bones assessed. The
For more information: Plevin S, McLellan J, O’Keeffe T. Association between sesamoiditis, subclinical ultrasonographic suspensory ligament branch change and subsequent clinical injury in yearly Thoroughbreds. Equine Vet J. 2015. [Epub ahead of print Oct. 29] ) http://onlinelibrary.wiley.com/doi/10.1111/evj.12497/ abstract
www.shanksvet.com • info@shanksvet.com ModernEquineVet.com | Issue 12/2015
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cover story
Headshaking Not a diagnosis you want to make
DACVIM, wants to put on a horse that “shakes” its head is headshaker, he said at the Northeast Association of Equine Practitioners annual meeting in Pittsburgh. “Headshaking is a really difficult problem to deal with,” he said. The true etiology is unknown; it is difficult to diagnose; and good treatments are lacking, explained Dr. Morresey, an internal medicine specialist at Rood and Riddle Equine Hospital in Lexington, Ky. In addition, there are many reasons why a horse could be moving its head. Therefore, a horse should not be diagnosed and labeled as a headshaker until all other differentials have been eliminated. Precipitating causes can be as simple as ill-fitting tack or a more-complicated disease process, he said. Classic characteristics of the clinical syndrome of headshaking are intermittent and violent swinging of the head up and down and side to side. The onset is typically early middle age—about 8 to 9 years old—and geldings are overrepresented. In addition, there appears to be a predilection among certain breeds, especially Quarter horses, Paints and Appaloosas. The problem tends to occur in late spring and summer, and exercise can exacerbate the condition. Headshaking is not normally associated with the horse looking behind, he said. It is associated with snorting and rubbing the nose. Some horses will strike their noses on surfaces and can actually do some serious damage. These actions imply some sort of irritation to the nasal cavity, he said.
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M a r i e
R o s e n t h a l ,
M S
Photo courtesy of www.boblangrish.com
One of the last labels that Peter R. Morresey, BVSc, MACVSc, DACT,
NOW AVAILABLE IN THE U.S. Over 250,000 doses administered worldwide in the last 12 years. Now FDA approved for use in the U.S. and available from your veterinary distributor, Tildren® (tiludronate disodium) controls clinical signs associated with navicular syndrome in horses. Tildren works at the areas of active bone resorption, restoring balance to the process of bone remodeling. Contact your local distributor or Ceva Animal Health representative for more information.
Do not use in horses with impaired renal function or with a history of renal disease. NSAIDs should not be used concurrently with TILDREN. Concurrent use of NSAIDs with TILDREN may increase the risk of renal toxicity and acute renal failure. Horses should be observed closely for 4 hours post-infusion for the development of clinical signs consistent with colic or other adverse reactions. Caution should be used when administering TILDREN to horses with conditions affecting mineral or electrolyte homeostasis (e.g. HYPP, hypocalcemia) and conditions which may be exacerbated by hypocalcemia (e.g. cardiac disease). The safe use of TILDREN has not been evaluated in horses less than 4 years of age, in pregnant or lactating mares, or in breeding horses.
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cover story
Bisphosphonate drug for intravenous infusion. For use in horses only. Brief Summary: See package insert for full prescribing information. Caution: Federal law restricts this drug to use by or on the order of a licensed veterinarian. Description TILDREN is a sterile powder. Each vial of TILDREN contains 500 mg of tiludronic acid (as tiludronate disodium) and 250 mg mannitol USP (excipient).
Indication TILDREN is indicated for the control of clinical signs associated with navicular syndrome in horses. Contraindications Do not use in horses with known hypersensitivity to tiludronate disodium or to mannitol. Do not use in horses with impaired renal function or with a history of renal disease. Bisphosphonates are excreted by the kidney; therefore, conditions causing renal impairment may increase plasma bisphosphonate concentrations resulting in an increased risk for adverse reactions. Warnings Do not use in horses intended for human consumption. NSAIDs should not be used concurrently with TILDREN. Concurrent use of NSAIDs with TILDREN may increase the risk of renal toxicity and acute renal failure. Appropriate wash-out periods should be observed between NSAID and TILDREN administration, and BUN and creatinine should be monitored. If treatment for discomfort is required after TILDREN administration, a non-NSAID treatment should be used. Human Warnings Not for human use. Keep this and all drugs out of the reach of children. Consult a physician in case of accidental human exposure. Precautions Approximately 30-45% of horses administered TILDREN will demonstrate transient signs consistent with abdominal pain (colic). Hand-walking the horse may improve or resolve the colic signs in many cases. If a horse requires medical therapy, non-NSAID treatments should be administered due to the risk for renal toxicity. Avoid NSAID use. TILDREN should be administered slowly and evenly over 90 minutes to minimize the risk of adverse reactions. Horses should be well hydrated prior to administration of TILDREN due to the potential nephrotoxic effects of TILDREN. Concurrent administration of other potentially nephrotoxic drugs should be approached with caution, and if administered, renal function should be monitored. Caution should be used when administering TILDREN to horses with conditions affecting mineral or electrolyte homeostasis (e.g. hyperkalemic periodic paralysis (HYPP), hypocalcemia, etc.) and conditions which may be exacerbated by hypocalcemia (e.g. cardiac disease). TILDREN should be used with caution in horses receiving concurrent administration of other drugs that may reduce serum calcium (such as tetracyclines) or whose toxicity may exacerbate a reduction in serum calcium (such as aminoglycosides).
Headshakers will have an unremarkable physical and neurological examination. If the veterinarian sees dental disease, oral mucosal ulcerations, pain in the neck or upper spine—those issues should be dealt with first to see if the headshaking is eliminated. There are several ideas about its cause. One is that it is a photosensitivity, equivalent to the human photic sneeze, which makes sense given its seasonal onset, he said. Researchers are starting to think that light stimulates the trigeminal nerve in the horse’s face and causes it to tingle, itch or burn, and the horse reacts by shaking its head or snorting, rubbing and banging its nose to stop the sensation. “In horses, headshaking can be tied to the daylight period, and headshaking is treated with melatonin,” he said. “So, it’s not a leap.” A similar syndrome is seen in humans who suffer photic sneeze or trigeminal neuralgia. In some individuals, bright light kicks the trigeminal nerve into action. They will get nasal engorgement, their eyes will run and they sneeze. It almost looks like an allergic reaction, but there is no allergic component to this, so that is what makes it so difficult to understand, according to Dr. Morresey.
Other people will experience a profound, acute onset of burning and itching that shoots across the face and feels like an electric shock. There are no other pathological signs. If horses suffer conditions similar to the human photic sneeze and trigeminal neuralgia, it’s easy to see where it might start violently shaking its head, he said. Another contributor may be a hormonal imbalance (which is why geldings might be overrepresented), vascular changes, or temporohyoid osteoarthropathy, according to Dr. Morresey. Some reports have linked it to an infection, but other studies have not borne that out. Seasonal allergy could also be a cause, especially in a horse that has a good bit of skin irritation, he explained. “Nasal irritation may be giving us a syndrome that is similar to the classic headshaker in horses. Like us, some of these horses suffer from allergies and these allergies are often going to be seasonal. You might see other things on this horse. Perhaps you will have urticaria and the horse is moving its head around in a noxious fashion, and the client will say, ‘My horse is a headshaker,’” Dr. Morresey said.
Diagnosis
“Headshaking is a diagnosis of exclusion.
Headshaker Treatment Treatment
Dose/frequency
Comments
Horses with HYPP (heterozygous or homozygous) may be at an increased risk for adverse reactions, including colic signs, hyperkalemic episodes, and death.
Cyproheptadine
0.3mg/kg PO q12h
The safe use of TILDREN has not been evaluated in horses less than 4 years of age. The effect of bisphosphonates on the skeleton of growing horses has not been studied; however, bisphosphonates inhibit osteoclast activity which impacts bone turnover and may affect bone growth.
Moderate improvement. Lethargy
Carbamazepine
2–8mg/kg PO q6h-q12h
Bisphosphonates should not be used in pregnant or lactating mares, or mares intended for breeding. The safe use of TILDREN has not been evaluated in pregnant or lactating mares, or in breeding horses.
Moderate improvement. (May be combined with cyproheptadine) Unpredictable efficacy
Hydroxyzine
1mg/kg PO q12h
Moderate improvement.
Fluphenazine
50 mg IM
Repeat 1–4 monthly. Neurological dysfunction.
Phenobarbital
3–6 mg/kg PO q12h
Calmative. Sedation.
Gabapentin
5–20 mg/kg PO q12h–q24h
Anecdotal reports, variable.
Corticosteroids
Standard dosage
Also variable success pulse therapy reported.
Magnesium
Variable
Calmative.
Melatonin
15–18 mg PO q24h
Altered hair shedding.
Increased bone fragility has been observed in laboratory animals treated with bisphosphonates at high doses or for long periods of time. Bisphosphonates inhibit bone resorption and decrease bone turnover which may lead to an inability to repair microdamage within the bone. In humans, atypical femur fractures have been reported in patients on long term bisphosphonate therapy; however, a causal relationship has not been established. Adverse Reactions: The most common adverse reactions reported in the field efficacy and safety studies were clinical signs consistent with abdominal discomfort or colic. Other reported signs were frequent urination, muscle fasciculations, polyuria with or without polydipsia, and inappetance/anorexia. For technical assistance or to report suspected adverse reactions, call 1-800-999-0297. Marketed by: Ceva Animal Health, LLC Lenexa, KS 66215 Tildren is a registered trademark of Ceva Santé Animale, France ®
NADA 141-420, approved by the FDA
Sodium cromoglycate eye drops Apply OU q6h 6
Issue 12/2015 | ModernEquineVet.com
Seasonal head shakers.
We need to get rid of all the organic causes of disease,” he said. Take a detailed history, including management procedures, diet, exercise and environmental changes. When investigating idiopathic headshaking following exclusion of other diseases, the horse should exhibit characteristic head motion of rapid downward motion of the nose followed by upward flinging of the head. The physical should include oral cavity, ophthalmic and otoscopic examinations. Endoscopy of the upper airway, including the guttural pouches, and radiography of the head and throatlatch region are indicated. Computed tomography and magnetic resonance imaging may help visualization bone and soft tissue. In some cases there is thickening around the trigeminal nerve. Local anesthesia of the infra-
orbital nerve has been used as an aid to diagnosis but reported success is low. In a study by Mair, et al., infraorbital anesthesia with 2% mepivacaine improved three out of 19 horses, had no effect on eight horses and worsened symptoms in another eight horses. In another study by Newton, et al, only one in eight horses improved and only by 50%, however, a lower dose of mepivacaine was given. Using more local anesthetic infiltration may affect adjacent nerves, he said. Bilateral anesthesia of the posterior ethmoidal nerve (maxillary nerve) improved 13 of 17 horses in one study and 23 of 27 horses in another. However, the location of the nerve requires an extended period for diffusion of the anesthetic to achieve a full effect, Dr.
Morresey cautioned. Management of the condition involves changes in the environment to minimize stimluli such as light and airborne irritants, and various medications that show some efficacy in some cases. Surgical approaches have been reported, however complication and reoccurrence rates are high, and improvements slight in most cases, meaning this approach is at best an attempt at salvaging the horse “It is quite interesting to talk to clients [about headshaking]; it almost seems like they tend to want their horse to be a headshaker so they can blame the behavior on something,” he said. “But I really, really don’t want them to have a headshaker. The owners just want something to fix it. And as we know, that is very difficult to do.” MeV
ModernEquineVet.com | Issue 12/2015
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dermatology
Wound care without the trauma Photo courtesy of Dr. Dean A. Hendrickson
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A dry wound with crusting after tumor removal
There’s an old adage in the
wound healing field that says, “Never put something on a wound that you would be unwilling to put in your eye.” It’s a simple premise, but it’s one that can be overlooked in general practice. “In the veterinary field, it’s a bit horrifying to consider all the things we put in horse wounds,” said Dean A. Hendrickson, DVM, DACVS, professor of clini-
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cal sciences at Colorado State UC University. “Think about someone coming by and squirting these things into your eye one week apart just to see how you would respond to it. Except for a hypertonic saline dressing, I don’t put anything in a wound that I wouldn’t put in my eye, and I’ve seen much better healing responses. Sometimes the animal heals in spite of us, not because of us.”
Wound Preparation
It is crucial to truly evaluate the wound, and Dr. Hendrickson recommended clipping the area first. “I had a horse that came in caked with dirt, blood and debris,” he explained at the 61st Annual AAEP Convention here in Las Vegas. “The skin edges had been carefully opposed with horizontal mattress sutures, but the horse became sorer as time went on. I
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ModernEquineVet.com | Issue 12/2015
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Wound Care
cleaned the wound and clipped the area, and two puncture wounds could be seen going into the carpus with synovial fluid leaking out. You can’t see what’s there until you get the hair out of the way.” After the hair is removed, cleaning the wound may be the most important step. Dr. Hendrickson noted that clinicians probably do more accidental harm to the wound at this stage. Gloves are necessary. If the wound is over an area of bone or a synovial membrane, then aseptic technique is indicated. Organisms are not picky. Whether it’s a stick, a rock, suture material or a $200 titanium screw, foreign material in a wound can affect healing and increase the infective dose of some organisms.
Evaluating the Antiseptics There are many antiseptic options, but all are not equal. Dr. Dean A. Hendrickson offered his thoughts on the available options. Chlorhexidine — This has a longer residual effect than povidone iodine, but the label says that we shouldn’t put around the cornea, in the ear, or in synovial structures. Any time we see that, we should probably look a little more carefully at what we’re doing. A study in 2012 in The Journal of Orthopaedic Trauma showed no statistical difference in the presence or quantity of bacteria with saline vs chlorhexidine. Hydrogen peroxide — The old argument for hydrogen peroxide was that if it was bubbling, that meant it was working. Its antimicrobial effect is overstated. A recent study in PLOS One showed that there is some benefit in low concentrations for enhancing angiogenesis in wound closure, but the process is slowed at high concentrations. Vinegar — Studies have shown that using vinegar on the right wounds and with the right bacteria can have great results. A solution of 0.25% or 0.5% has shown to have bactericidal effect against grampositive and gram-negative organisms, with particular effectiveness against Pseudomonas species. 10
Issue 12/2015 | ModernEquineVet.com
Moist wounds are happy wounds. The balance between dry and wet can make the difference in helping the wound heal. “In some cases, wounds are dirty and need to be cleaned, but if you stop for a minute and are honest about the situation, then we have to admit that everything we do to a wound causes some trauma to the wound bed,” Dr. Hendrickson explained. In 1919, Dr. Alexander Fleming said that it was impossible to sterilize a wound using an antiseptic. Almost a full century later, there has not been a controlled clinical study that refutes that assertion. The best case scenario for antiseptics is to reduce the bacterial burden, but standard antiseptic therapy tends not to do that as well as is commonly thought. Povidone iodine, the unofficial gold standard in veterinary and human medicine for wound care, has been used in countless wounds, but the controls in the published clinical studies were fairly suspect, Dr. Hendrickson said. In fact, studies have repeatedly failed to show that povidone iodine promotes healing, and it can actually impair wound healing, reduce wound strength and can lead to infection. The povidone iodine effectively causes necrosis of the tis-
sue that functions as foreign material leading to increased bacterial counts. “I come from a ‘big hammer’ family in northern Montana,” Dr. Hendrickson joked. “If I did something with a small hammer that didn’t work, then I just got a bigger hammer. We do a lot of that when we scrub. If a little bit of scrubbing doesn’t clean the wound, then we scrub harder. I would ask that clinicians ignore that second step. If the wound isn’t cleaned with gentle scrubbing or lavage with a moist sponge using a physiologic agent such as saline or lactated Ringer solution, then try something else.”
Antibiotics
Dr. Hendrickson tends to shy away from continued use of systemic antibiotics following an initial “blast” dose, but topical antibiotics can be highly valuable for equine wound care. Silver sulfadiazine (SSD) cream is a common choice in wounds in both equine and human medicine. Silver impregnated dressings elute silver into the wound to kill the bacteria and can be easily removed following use. This can offer a respite from having to apply SSD cream to a wound and then having to use lavage or scrub the wound to remove the cream. Nitrofurazone is another commonly used topical antibiotic in horses, but Dr. Hendrickson is not sold. “As much as we use nitrofurazone in horses, there is not one positive study for its use in wound healing,” he explained. “I sometimes joke that if you’re going to investigate a new topical agent then you should use povidone iodine and nitrofurazone as control agents, because almost everything looks better than these two.” Triple antibiotic ointment (bacitracin, neomycin and polymyxin B) has shown some great effective-
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Photo courtesy of Dr. Dean A. Hendrickson
Wound care
Wound after it had healed using moist wound healing techniques.
ness. The product was launched in the 1950s as a prescription and in the 1970s as an over-the-counter agent, and the resistance pattern has had almost no change since its inception. “SSD, triple antibiotics and surfactant-based cleansers are some of the things that we can put on a wound to minimize our negative impact on the wounds themselves,” Dr. Hendrickson said.
Wound dressings
Moist wounds are happy wounds. The balance between dry and wet can make the difference in wound healing. “I believe that you must keep a wound moist if you want the most effective healing to take place,” Dr. Hendrickson said. “Choose a dressing that helps to accomplish this.” Debridement dressings (e.g., hypertonic saline) are simple, easy to use and essentially suck fluid out of the bacteria until they die. 12
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Dr. Hendrickson prefers 20% saline dressings. Healthy cells can handle this solution of saline, but tenuous cells cannot. “I change dressings based on the amount and character of the exudate, not by the calendar,” he said. “If a wound has a lot of exudate, I will change dressing frequently because the exudate can dilute the hypertonic saline. For wounds with less exudate, I may cover the dressing with plastic to maintain moisture.” It is important to never use hypertonic saline directly over bone. This may lead to bone sequestrum. Dressings that are impregnated with polyhexamethylene biguanide (PHMB) are available in sponges, roll gauzes and other types. These dressings are designed to stop bacterial penetration to wounds, but they can also kill the bacteria within the wounds themselves. “Other uses for PHMB include contact lens solutions, so this works out well for our goal,” he said.
PHMB works by disrupting the outer phospholipid membrane and allowing the cytoplasm to leak out. Dr. Hendrickson recommended moistening the dressing before placing it. “I no longer believe that horses create more exuberant granulation tissue than other species,” he noted. “I think equine veterinarians create more exuberant granulation tissue than other species. For years we were always afraid to consider granulation tissue in horse wounds because the wounds we dealt with already had so much exuberant granulation tissue.” In the right environment, however, granulation tissue can be helpful to cause wound contraction and help wounds heal faster. One of Dr. Hendrickson’s preferred dressings for this purpose involve alginate, a derivative of seaweed. The dressings come in a nonwoven pad and also include calcium to encourage wound contraction. Wound exudate tends to be high in sodium; the dressing pulls in the sodium and donates calcium to the wound. “One thing to note about these is that they are very absorptive,” he said. “If you have a wound on the edge of being dry and you put a calcium alginate dressing on it, it will desiccate the wound. I always pre-moisten these with saline solution.” Alginate dressings also stimulate the granulation beds to come through bone. If a bone is exposed, Dr. Hendrickson recommended curetting and debridement followed by a moistened alginate dressing. The bone should be debrided until it is bleeding or glistening. “I can cover an almost completely denuded, dry, chalky cannon bone and have it covered in granulation within about seven days with calcium alginate,” he said. “I have not had a horse develop a bone sequestration as a result.” MeV
Sports Medicine
Risk factors exist in horse
racing in Switzerland, which are specific to each discipline (trot, flat and obstacle), according to a new study by researchers at the University of Berne. This retrospective study aimed to evaluate the risk factors related to clinical injury in various horse racing disciplines in Switzerland. The researchers analyzed all race starts in flat, obstacle and trot racing over four years, including a total of 17,760 race starts in 1,738 races at 10 racecourses. The age, sex, earnings, distance and time raced, place, jockey/driver, owner, trainer, track surface typeand (if grass) the surface conditions were recorded. Racetrack veterinarians recorded clinical and non-clinical observations and recorded these with a standardized Veterinary Code system. At least one Veterinary Code was
recorded for 525 horses: the most common was non-clinical one, i.e. Non-Starter. The highest incidence of Veterinary Codes was associated with obstacle races (106/1000 starts), followed by flat races (27/1000) and then trot races (21/1000). Multivariable logistic regression models were used to analyze risk factors in each discipline. Horses were more often recorded as fallen or pulled up in obstacle races than in other disciplines. Horses finishing over eighth place had a higher risk of clinical events than those placed 1–3 in flat, obstacle and trotting races. In trot racing, gait abnormalities and lameness were the most common Veterinary Codes recorded and there was a lower risk of clinical events for runners on Porphyre sand than on grass. The risk was approximately doubled for those whose driver was also their train-
er. The researchers speculated that this may be due to trainers feeling more able to take risks when driving their own horse. In flat racing, one race course had a higher risk of clinical events than some of the others but no associations were found relating to the race course surface. Obstacle races of over 2,401 meters carried a lower risk of injury. The researchers pointed out that some confounding factors may account for some of the associations found in this study, and that there is a need to improve the standardization of event recording. However, the study represents a positive initial step in identifying risk factors for racing injury that may allow steps to be taken toward prevention. Further study is required to determine how these factors influence rates of injury and how they can be reduced. MeV
Shutterstock/ Ventura
Risk factors for injury in Swiss horse racing
Š
For more information: Schweizer C, Ramseyer A, Gerber V, et al. Retrospective evaluation of all recorded horse race starts in Switzerland during a four year period focusing on disciplinespecific risk factors for clinical events. Equine Vet J 2015 [Epub ahead of print Nov. 18, 2015] http://onlinelibrary.wiley.com/doi/10.1111/evj.12515/abstract ModernEquineVet.com | Issue 12/2015
13
news notes
UC Davis Integrates Sports Medicine for Horses
Photo courtesy of University of California Davis
A burgeoning service at the UC Davis veterinary hospital is its Equine Integrative Sports Medicine Service. Consisting of an array of complementary medical and evaluative procedures, the service is attracting many clients looking to maximize the performance of their sport horses. Led by Sarah le Jeune, CVA, Cert, Vet. Chiro, DVM, assistant professor of clinical surgical and radiological sciences, who is board certified in surgery and sports medicine/rehabilitation, as well as certified in acupuncture and chiropractic, the service offers treatments and
Dr. Sarah le Jeune applies a chiropractic treatment at the Equine Integrative Sports Medicine Service at UC Davis veterinary hospital.
evaluations of the entire equine athlete. With the subtlest issues potentially affecting an athlete, Dr. le Jeune said it is important to examine every aspect of a horse and its equipment, right down to a blanket or a small piece of tack. Beyond physical limitations such as injuries, equipment can certainly play a role in determining the success of an athlete. One of the most important elements of peak performance can be proper saddle fit. Ill-fitting saddles can be a determining factor in a horse with back pain. Many saddles are too narrow and can pinch a horse’s back, causing significant restrictions of back movement, which is critical to proper functionality of an athlete. Many of Dr. le Jeune’s patients compete in dressage, where a horse’s performance is judged on its gaits and movements. Even the slightest ailment can cause a decrease in performance and ultimate score. So while Dr. le Jeune evaluates for limb lameness and other significant ailments, she also examines secondary factors like a horse’s hoofs, teeth, and diet. The benefit for her 14
Issue 12/2015 | ModernEquineVet.com
clients of using UC Davis is that if Dr. le Jeune discovers a dental or nutrition issue, she can consult with UC Davis’ board-certified experts in those areas without having to refer the horse to another facility, saving her clients added trips to other locations. Many of Dr. le Jeune’s appointments are not at the hospital. She prefers to see horses in their home environment. Traveling to a hospital can cause a horse’s adrenaline to mask any mild or subtle issues it may have. By seeing them in their natural environment, however, horses remain calm and the evaluation will reveal their true state of health. Home visits also give Dr. le Jeune an opportunity to evaluate a training session with a horse’s rider and trainer, giving her a better understanding of that horse’s condition. Often times, Dr. le Jeune will even ride a horse herself to get a feel for more subtle issues that can only be discovered by riding rather than by examining. Working with trainers is important to gain insight into the full background of a horse and what may be affecting its optimal performance. Is the horse having behavioral issues or is it in pain? “In my experience, most of those issues are pain related,” said Dr. le Jeune. “Rarely are there truly primary behavioral issues. Most horses want to do what we want them to do. The reason they’re not doing a particular task is because there’s pain.” After discovering the cause of pain, there are several treatment options Dr. le Jeune can perform. Some major injuries will require surgery, and she will work with clients to rehabilitate the horse and hopefully return it to competition. Recovery for equine athletes is similar to that for human athletes, and Dr. le Jeune will team with trainers to determine the proper timing of recovery procedures and workouts. Many times, an athlete’s back, neck or muscle pain can be treated with chiropractic and acupuncture treatments. These procedures are becoming increasingly popular, and can easily be integrated into conventional diagnostic and treatment modalities to optimize clinical outcome. In addition to equine athletes, Dr. le Jeune also sees livestock athletes, such as bucking bulls. Bulls with back pain simply won’t perform. Like other animals, many livestock also respond positively to acupuncture to alleviate their pain. Previously, she has used acupuncture to optimize the performance of a popular bull from the Professional Bull Riders tour. Not every patient of Dr. le Jeune’s is an athlete, though. Many non-athletes also benefit from her service, such as geriatric or arthritic horses that have MeV trouble standing up and laying down.
AAEP Honors Dr. Nathaniel A. White II, Others influenced by Dr. Reef, whether in the classroom, in the lab or through her hundreds of publications that include more than 50 original re- Nathaniel A. White II, Virginia Reef, DVM, DACVIM, DACVSMR, search papers, over DVM, MS, DACVS DECVDI 50 case reports, about 130 abstracts in proceedings, 11 major review articles and 80 book chapters. Dr. Reef is an invited speaker at domestic and international meetings. Her dedication to expanding ultrasonography technique among her veterinary colleagues is further evident when conducting wet labs. Dr. Reef seeks out local practitioners to procure live horses with the types of injuries she is teaching, arranges shipping of these horses to the wet lab and coordinates co-instructors and assistants to ensure a first-class learning experience for attendees. Dr. Reef earned her DVM in 1979 from The Ohio State University. She completed her internship and residency in large animal medicine in 1982 at Penn Vet, where she has served on the faculty ever since. She is the Mark Whittier and Lila Griswold Allam Professor of Medicine as well as section chief of sports medicine and imaging at Penn Vet’s New Bolton Center. Among her honors and awards are the Michael Moxon Kate Memorial Distinguished Lecturer Award and The Ohio State University Distinguished Alumnus Award. Recently retired, Dr. Lee's enthusiastic support and guidance of new veterinarians and students helped shape many successful careers. The Distinguished Educator—Mentor Award honors an individual who has demonstrated a significant impact on the development of equine practitioners through mentoring. A 1974 graduate of Cornell University, Dr. Lee founded Unionville Equine Associates in Oxford, Penn., where he practiced from 1983 until relocating to New Mexico in May. During this time, he nurtured the confidence and development of his young team members gradually by presenting challenges in a manner that encouraged independent thinking while honing their craft. Dr. Lee also promoted a healthy growth trajectory by helping his team develop professional connections throughout the industry and by presenting opportunities for career advancement. His influence also extended to students through institution of a formal internship/externship program at the practice and his enthusiasm to share his joy of veterinary medicine and serve as a source of advice and support to the many high school, college and veterinary school stuMeV dents who shadowed Dr. Lee on ride-alongs.
John W. Lee Jr., DVM
Photos courtesy of AAEP
The American Association of Equine Practitioners (AAEP) presented Nathaniel A. White II, DVM, MS, DACVS, with the Distinguished Life Member Award for his leadership and substantial volunteerism within the association during his 43 years of membership. The Distinguished Life Member Award honors an AAEP member who has made outstanding contributions to the association throughout his or her career. Dr. White, professor emeritus of equine surgery at Virginia-Maryland College of Veterinary Medicine’s Marion duPont Scott Equine Medical Center and president of the AAEP in 2010, is chair of the AAEP’s National Equine Health Plan Task Force, which is establishing an Equine Disease Communication Center to serve as a national hub for equine disease reporting. He serves on the management board and as co-U.S. editor of Equine Veterinary Education. A 1971 graduate of Cornell University, Dr. White was instrumental in the establishment and served as longtime chair of the AAEP Foundation, which has distributed more than $3.3 million to improve the welfare of the horse. He served two terms on the AAEP board of directors, volunteered with the AAEP On Call program from 1994–2000, delivered the 2006 Frank J. Milne State-ofthe-Art Lecture and received the AAEP’s Distinguished Service Award in 2004. Since joining the AAEP in 1973, Dr. White has also volunteered his time and expertise through service on numerous committees and councils, including Abstract Review, Convention Planning, Educational Programs, Finance, Nominating, President’s Advisory, Public Policy, Research, Student Relations, and Trail and Events. Also honored were Virginia Reef, DVM, DACVIM, DACVSMR, DECVDI, director of large animal cardiology and diagnostic ultrasonography at the University of Pennsylvania School of Veterinary Medicine, who received the American Association of Equine Practitioners 2015 Distinguished Educator—Academic Award and John W. Lee Jr., DVM, who received the 2015 Distinguished Educator—Mentor Award. The Distinguished Educator—Academic Award honors an individual who has demonstrated a significant impact on the development and training of equine practitioners. A pioneer in the diagnostic use of ultrasonographic technology, Dr. Reef perfected the technology in her clinical use and then taught it to students and practitioners alike. In the ensuing 30-plus years, ultrasonography has contributed to early diagnosis of musculoskeletal injury, significantly reducing catastrophic athletic tendon and ligament injuries. Many practitioners who use ultrasound have been
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AAEV T M E M b E r s h i p Membership in the AAEVT is open to all veterinary technicians, assistants, support staff and those employed in the veterinary health care industry worldwide. Student membership is open to those currently enrolled in an AVMA/CVMA accredited veterinary technology program.
AAEVT Membership • • • • • • • • • • •
Bi-Annual Newsletter Weekly “HoofBeats” Email Newsblast Full access to www.aaevt.org, including the Career Center and the Library Up-to-date information on the AAEVT Discounted registration for AAEVT Regional Meetings and the annual AAEP/AAEVT Convention NTRA, Working Advantage and Platinum Performance Benefits The opportunity to participate in the AAEVT Online Certification Program or to become a member of the AEVNT Academy-Specialty in Equine Veterinary Nursing Scholarship opportunities. AAEVT’s Equine Manual for Veterinary Technicians (Blackwell Publishing 20% discount on purchase price) Opportunity to attend Purina’s Annual Equine Veterinary Technician Conference - All Expenses paid!
AAEVT Objectives • • • •
Provide opportunities for CE, training, communication, and networking Educate the equine veterinary community and the public about our profession Inform Members of issues affecting our profession Assist in providing the best medical care to improve the health and welfare of the horse
AAEVT Online Equine Certification Program
• A three course, 10 module, equine-only online program offered through ACT • Geared toward Credentialed Veterinary Technicians, Assistants, Support staff, & Students • Areas of study include: equine medical terminology, anatomy and physiology, parasitology, laboratory, diagnostics, equine basics (breeds, wellness, husbandry,) diagnostic procedures, emergency medicine, restraint, pharmacology, surgical assistance and anesthesia, equine office procedures • A certificate of completion is awarded to those who: Successfully complete required courses Complete the list of required skills (per a supervising DVM who is an AAEP member) Attend an AAEVT regional CE symposium and participate in the we labs • Those individuals who successfully complete the programs will be recognized as AAEVT Certified Equine Veterinary Technicians / AAEVT Certified Equine Veterinary Assistants depending on their current designation. The certificate is recognized by the AAEVT and the AAEP but does not grant the credentialed status by the AVMA • For more information go to www.aaevt.4act.com or call 800-357-3182
AAEVT Mission Statement: To promote the health and welfare of the horse through the education and professional enrichment of the equine veterinary technician and assistant.
Fo r m o re i n f o r m a t ion v ist w w w.a ae vt.or g
*American Association of Equine Veterinary Technicians and Assistants
technician update
Surgical Removal of a Sequestrum on the Proximal Tibia By Jenna Powell, BS, RVT of San Dieguito Equine Group A 17-year-old mare, used for polo, was presented for treatment of a wound with a chronic draining tract. The wound occurred approximately four weeks prior to presentation when the mare was kicked while in the pasture. The wound was located on the mare’s proximal left hind limb, corresponding with the cranial aspect of the proximal tibia. Radiographs were taken one week prior to presentation and confirmed the presence of a sequestrum. The wound was cleaned and aseptically probed. The wound tract extended to the surface of the proximal tibia. The bone surface was rough and irregular. An ultrasonogram showed an irregular surface on both the proximal and cranial surfaces of the tibia. The irregular surfaces corresponded with the presence of the sequestrum. In the interest of proper healing and a return to work, the horse underwent surgery for debridement of the bone surface and removal of the sequestrum. The mare was brought to the clinic five days later and surgery was scheduled for the next day. The pre-surgical bloodwork revealed that the mare was healthy and able to undergo the planned general anesthesia. For the surgery, a 14-gauge, 5.25 inch IV catheter was placed in the left jugular vein, and 3 g of IV gentamicin and 2 g IV phenylbutazone were administered. Nine million units of IM procaine penicillin G and 5 mg of detomidine were administered, and the patient was walked to the surgery suite. The mare was tranquilized with 350 mg xylazine. Anesthesia was induced using 30 mg of diazepam and 1.5 g of ketamine. The induction went smoothly, and the patient was placed in right lateral recumbency on the surgery table. The surgical plane of anesthesia was maintained using inhaled isoflurane. The left hind leg was clipped from hock to stifle and then aseptically prepped and draped with an Ioban. An orthopedic surgical drape was then placed over the whole leg. An 8 cm incision was made over the cranial aspect of the proximal tibia and the abnormal tissue of the draining tract was identified and resected. The cranial surface of the tibia and the sequestrum were debrided. The bone surface was lavaged with saline and amikacin. Next, the subcutaneous tissue was closed over the bone surface using absorbable suture. The cutaneous tissue was closed with non-absorbable suture.
The patient was taken off of isoflurane inhalation anesthesia as the closing of the surgical incision was started. A sterile bandage was placed over the surgical site. The mare was moved to recovery and placed in right lateral recumbency. The mare had a smooth recovery but spent a prolonged period in lateral recumbency before standing. The mare was administered 5 g IV methocarbamol after standing to help with residual muscle spasms and cramping. The day after surgery, the mare was sore and stiff on her left hind leg but began to ambulate more freely as she walked. The mare was released to her owner with instructions to keep the mare on stall rest. The owner was given the following medications to administer: 1.5 g doxycycline to be given orally twice a day for 14 days and 2 g phenylbutazone to be given orally once a day for five days. An appointment was made to recheck the mare three days postsurgery. At her three day recheck, the mare was bright and eating, drinking, defecating, and urinating normally. She was ambulating well, the incision site was clean and the sutures were in place. There was no peri-incisional edema. At a recheck eight days after surgery, there was moderate swelling of the surgical incision and there was slight gaping at the proximal aspect of the incision. Aspiration of the peri-incisional edema showed that a seroma had formed at the incision site. The seroma was infused with 600 mg gentamicin, and the two distal sutures were removed from the incision site to facilitate draining. Five days later (day 13 post-surgery), the surgical site was rechecked. The seroma was still present, and the incision site was sterilely prepped and drained again. Amikacin was infused into the seroma. At that time, the owner was advised to keep the mare on 1.5 g doxycycline orally twice a day for an additional seven days to help with any possible infection associated with the seroma. The mare was checked two more times in the following week, and made good progress. At the final recheck 23 days after surgery, the mare was given clearance to make a gradual return to work provided that she did not become lame with increased exercise. Special thanks to Dr. Maureen Kelleher and Dr. Michael Manno for their assistance. MeV
About the author
By Jenna Powell, BS, RVT, is an equine technician at San Dieguito Equine Group in San Marcos, Calif. ModernEquineVet.com | Issue 12/2015
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