b'HIND-LIMB ENIGMASmovement or hip hikes, an unwilling- equinecondition. While its mostgreatly decreased, thereby magnifying ness to bring a leg forward, toe dragging,common in geriatric horses, OA canthe traumatic forces on the cartilage and and a bunny hopping canter are just ahavedevastating effects on any equinebone, says Durham.few routine signs of hind-end lameness.athlete, dramatically interfering withWhile OA can develop in any joint, its No two presentations are the same. performance. a common cause of hock pain. The hockcomprises four joints. The lowest two, Imaging the Hind Limb the distal intertarsal and tarsometatarsal Before choosing an imaging method, With distal hock OA,joints, are especially susceptible. veterinarians perform diagnostic analge- it is common for bothWith distal hock OA, it is common for sia (joint blocking) to isolate lameness toboth limbs to be affected, which means a certain area. Because vets perform mostlimbs to be affected,the clinical signs can be a little less obvi-of their equine work on the farm, stallsidewhich means the clini- ous and can creep up over time, says radiographs (X rays) are the modality ofDurham. In horses where hard stops are choice for evaluating any bone or jointcal signs can be a littlecommon, such as in many Western disci-in this setting. Radiography, however,less obvious and canplines, the horse may tend to overuse the does not reveal many details about softfront end when stopping or have a slower, tissue. Ultrasound is ideal for evaluatingcreep up over time.stuttering stop.tendons, ligaments, or other soft tissueDR. MATTHEW G. DURHAM Thankfully, veterinarians have many structures in the field. OA management and treatment options Your veterinarian might choose toOA starts as inflammation in a jointavailable to them. The least invasive prod-perform advanced imaging back at the(synovitis), progresses to arthritis whenucts are nutraceuticals, better known as hospital. There, he or she can use nuclearthe cartilage becomes involved, and finallyoral joint health supplements, containing scintigraphy to better pinpoint a problemto osteoarthritis when the bone surround- glucosamine, hyaluronic acid (HA), and area, along with magnetic resonanceing the joint starts to remodel, says Mat- other compounds. imaging (MRI) or computed tomographythew G. Durham, DVM, Dipl. ACVSMR,Practitioner-prescribed non-steroidal (CT) to further evaluate more insidiousof Steinbeck Peninsula Equine Clinics, inanti-inflammatories (NSAIDs) such as conditions such as proximal suspensorySalinas, California.phenylbutazone and firocoxib can also ligament desmitis, navicular bursitis, orCartilage has incredible compressionbe helpful. However, chronic usage does sesamoidean ligament conditions. Letsand tensile strength. Synovial fluid, whichincrease a horses risk of developing gas-review five conditions they might find. is produced by the lining of the joint sac,tric ulcers and kidney disease, so discuss acts as an outstanding lubricant for jointthese drugs with your veterinarian.Osteoarthritis (OA) surfaces and also provides nourishmentSystemic injectable treatments are Osteoarthritis is not just your grand- for cartilage. When the joint becomesoften effective, Durham says. Legend mothers diseaseits also a commoninflamed the lubricatingabilities are(intravenously administered HA) helps to restore synovial fluid to its normal state and is picked up by inflamed joints anywhere in the body. Adequan (intra-muscularly administered polysulfated glycosaminoglycan) is incorporated more directly into cartilage. In horses with multiple joints affected, particularly geriatric horses, these treatments can be very effective.Hock injections are one of the most common joint injections veterinarians perform in the field. But not all injection cocktails are equal. Of the many com-binations available, corticosteroids are the mainstay. They work to reduce the inflammation in OA cases and minimize damage to synovium and cartilage.Newer joint injection treatments leverage the bodys own immune system to treat itself, says Durham. Various systems use different tactics but, in general, blood is drawn and processed in a way that encourages expression of certain proteins which have potent 16August 2020The Horse|TheHorse.com'