b'SPONSORED BYartery with one lever, then makes the finalis a tendency to label all orthopedic inju-cut for testis removal. The Serra crushesries in young horses as osteochondrosis, the artery and removes the testis at once. and some are likely caused by trauma, she The researchers tested the methods onbelieves the veterinary community needs a two groups of 40 equine cadaversonebetter definition of osteochondral lesions.group using an open technique (incising the parietal tunic, or the sac surroundingSubchondral Bone Cysts & Stressesthe testis) and the other using a closedSantschi et al. examined how subchon-technique (removing the parietal tunicdral bone cysts (subchondral lucencies, or with the testis). Then they further splitSCLs, a common finding in radiographs at the groups, castrating half using the Serrapublic auction) in the stifles medial femo-and half using the Reimer emasculators.ral condyle impact local bone stresses. The team found few differences be- They ran a CT scan on a yearling, then COURTESY DR. ERIC MUELLERtween the groups. Leaking pressure wasdesigned a 3-D model in which they could Both the Serra (pictured) and the Reimer emas-higher (less likely to bleed after castration)culators are effective for equine castration. create cysts and load the joint to see in the open group with the Reimer, shehow it reacts to different degrees of stress.said, and within the Reimer group, it wasstudy in which researchers tested the du- The team found significant differences higher for open than closed castration. ration of action of two local anesthetics in tension and shear stress (in which the But ultimately, Santschi said, eithermepivacaine and lidocaineon eightstructures shape deforms) throughout emasculator works fine. horses with induced forelimb lameness.cyst development, which could lead to fur-They found that: ther bone damage and cyst enlargement. Navicular Bursotomy Outcomes Mepivacaine resolved lameness in eight; These data provide a first step in un-Horses with septic or contaminatedLidocaine resolved lameness in three; derstanding the altered mechanics of sub-navicular bursae typically face a long andBoth resulted in skin desensitization inchondral bone surrounding a SCL, they uncertain road to recovery. Even with sur- all horses, but it happened sooner thansaid. Additional studies may provide the gical intervention, prognosis is typicallylameness resolution after mepivacainebasis for improved treatment strategies guarded. To try to improve outcomes,administration; and for SCL in young horses and may improve a research team added regional limbLameness resolution and skin sensitiv- the understanding of SCL in humans.perfusion (RLP) to the equation. Santschiity lasted longer with mepivacaine.shared the results of their study of 19The researchers concluded that mepi- PRP to Treat Endometritishorses that were at least lame at the walk. vacaine is superior, with a reliable onsetA group in Brazil studied the effects of Horses underwent a navicular bur- and longer duration of action.administering intrauterine platelet-rich sotomy, in which the surgeon opened theplasma (PRP, which has anti-inflamma-bursa through the bottom of the hoof andJoint Lesion Heritability, Prevalence tory properties) on uterine inflammation lavaged the affected area with sterile fluid,When potential buyers are perusing(endometritis) and conception rates in in combination with RLP, which deliverssurvey radiographs of yearlings theyremares with persistent-mating induced high levels of drugs to leg tissues below ainterested in purchasing at a sale, osteo- endometritis (PMIE). Mares with PMIE tourniquet, and systemic antimicrobials.chondral lesions arent an uncommonhave lowered chances of conception. Santschi said horses underwent two tofinding. But just how common are they inThe team evaluated 13 mares with his-three more RLP treatments and therapeu- Thoroughbreds, and are they hereditary?tories of PMIE bred via artificial insemina-tic shoeing at the surgeons discretion. In a retrospective study scientists re- tion (AI) once over each of three estrous All horses survived. Sixteen returnedviewed 34 radiographs from each of 1,962cycles. During the control cycle mares to their previous use, and three becameThoroughbred yearlings in Australia.received no treatment. In the second cycle pasture-sound. The team reported that allThey identified osteochondral lesions andthey infused mares with PRP 24 hours 19 horse owners were satisfied with theanalyzed the horses pedigrees to estimateprior to AI, and in the third, they infused outcomes and deduced that bursotomy inheritability. Their key findings included: with PRP four hours after AI. combination with systemic and local an-23% of yearlings had at least one lesion; There was a significant decrease in timicrobials is an effective treatment forLesions were found in 10% of stifle, 8%markers of inflammation in both treated septic or contaminated navicular bursas. of fetlock, and 6% of hock joints; cycles compared to the control cycles,Overall heritability ranged from 0% tosaid Turner. Similarly, on histology Mepivacaine vs. Lidocaine in Blocks about 20%, with an average of 8%; and (microscopic evaluation) and biopsy there Vets perform palmar digital nerve Heritability was 16% for stifle lesions,was a significant decrease in evidence of blocks (PDNBs) to numb the hoofs rear2% for fetlock, and 0% for hock. endometritis in PRP-treated mares.portion for diagnostic and treatmentSantschi cautioned that while this studyTo see if this meant improved fertility, purposes. PDNBs must last long enoughrevealed a modest genetic component,the team determined pregnancy rates 14 for them to gather the information theyreprior studies have shown a higher degreedays post-ovulation on each cycle. Control seeking. Santschi shared the results of aof hock lesion heritability. Because there(Continued on page A16)March 2018THE HORSE AAEP Wrap-Up TheHorse.com/AAEP2017 A13'