b'YOUR GUIDE TO THE 2017 AAEP CONVENTION SPONSORED BYThe Lateston LamenessALEXANDRA BECKSTETT;ERICA LARSONThe Most Common WesternPerformance Horse Lamenessesesearchers have identified muscu-loskeletal issues prevalent among horses in many disciplines knowledge that helps vets take steps to reduce injuries. However, until recently, these figures hadnt been well-quantified in Western performance horses. Sherry A. Johnson, DVM, and col-leagues investigated diagnostic blocking patterns (using analgesia to locate pain) in Western performance athletes. Johnson isBIANCA MCCARTYa sports medicine and rehabilitation resi-dent at Colorado State Universitys (CSU)Regarding blocking patterns: bone to the top of the long pastern; two College of Veterinary & Biomedical Sci-Veterinarians localized forelimb lame- sesamoid bones sit to the junctions rear. ences, in Fort Collins, and Equine Sportsnesses most commonly using a palmarThe long pasterns sagittal groove (which Medicine LLC, in Pilot Point, Texas. digital nerve block (which numbs theunderlies the ridge in the bottom of the The team reviewed 10 years of medicalheel and part of the hoof walls), ancannon bone) is a common site of race-records of horses competing in West- abaxial sesamoid nerve block (whichhorse injury. While many of these injuries ern performance classes and reining atdesensitizes the entire hoof from ap- in racing horses have a good prognosis for nationally sanctioned competitions. Theyproximately below the fetlock jointreturn to athletic function, how they im-focused on identifying the affected limbs,down), or a combination of the two;pact other horses has remained unclear.lameness grades, and diagnostic analge-They localized hind-limb lamenessesSarah Gold, DVM, carried out the first sia patterns. They only included horsesmost commonly to the proximalstudy evaluating MRI characteristics andwith performance-related lameness andmetatarsal/distal tarsal (top of cannonoutcomes of sagittal groove injuries in complete diagnostic work-ups.bone/lower hock) region (16% of cases).nonracing horses. Gold is a sports medi-In all, they reviewed records fromThe team found 47 nonlocalizablecine vet at B.W. Furlong and Associates, 2,677 lameness exams on 2,521 horses.hind-limb lamenesses, in contrast with 11in Oldwick, New Jersey, and Advanced The team knew specific disciplines fornonlocalizable forelimb lamenesses.Equine Imaging of Wellington, in Florida.73.5%1,188 were all-around WesternThe pelvis as a source of pain thatGold and colleagues reviewed medi-performance horses, and 616 were rein- manifests itself as diagnostically nonlo- cal records from 2007 through 2016 and ers. Most were Quarter Horse geldings.calizable hind-limb lameness should beidentified 19 Warmbloods with sagittal Key findings included: considered in these cases, Johnson said.groove injuries examined using MRI.The primary lame limb was the rightUltimately, she said, the team foundFour horses had a history of chronic forelimb in 809 horses, left forelimb inits still challenging to pinpoint lamenesslameness that became acutely severe; 15 695 horses, right hind in 616 horses,source using diagnostic analgesia. Buthad a one- to nine-week history of lame-and left hind in 557 horses; continued research on how Western per- ness. Gold said clinical signs were variable The average lameness grade was aboutformance horses respond to nerve blocksand not specific to the fetlock. How horses 2 on a 5-point scale; could help vets better define the mostblocked to different diagnostic anesthesia 56.3% of horses had a secondary lame- common injuries in that discipline. injections also varied greatly and was not ness, 17.4% had a tertiary lameness; always specific to the fetlock. Vets didnt All-around horses were most likely toSagittal Groove Injury Outcomes inperform blocks on two horses, opting for have a single hind-limb lameness; and Warmblood Horses nuclear scintigraphy (bone scan) to check Reining horses were most likely to haveThe fetlock is a complex high-motionfor suspected fractures, with a plan for a single forelimb lameness. joint that joins the bottom of the cannonMRI based on results. All horses were March 2018THE HORSE AAEP Wrap-Up TheHorse.com/AAEP2017 A17'