b'YOUR GUIDE TO THE 2017 AAEP CONVENTIONWarmblood horses diagnosed with sagit- consider adding advanced imaging (suchand adjusting front hoof balance thantal groove injury and concurrent osteoar- as MRI) to exams to allow for earlierrear hoof balance. This is because front thritis is poor, she said. diagnosis and treatment if no other lame- imbalances typically manifest as obvious She advised veterinarians to alwaysness causes are identified. foot pain. Rear limb imbalances are less evaluate the fetlock when clinical work- obvious but just as critical to monitor, up, imaging, and treatment do notRear Hoof Imbalance and Lameness however, because they can cause pain produce desired results, as fetlock injuryHistorically, veterinarians and farri- higher up in the limb and body.can cause similar signs. She also said toers have spent far more time evaluatingIve spent the majority of my career talking about front feet, said Tracy Turner, DVM, MS, Dipl. ACVS, ACVSMR, of Turner Equine Sports Medicine and Surgery, in Stillwater, Minnesota. I started looking and realized that rear hoof imbalance has been largely ignored. But rear hoof imbalance might have more effect on the upper body due to its direct attachment to the axial skeleton (the ver-tebrae, skull, ribs, and sternum). The hind leg attaches directly to the pel-vis, which attaches to the sacroiliac joint, which attaches to the vertebrae. You cant move those parts until the foot leaves the ground, said Turner. Theres a lot more effect on all those joints. The horse can move and adjust his front limbs more eas-ily, without affecting his upper body. When the horse lifts his hind foot off the ground, he must contract his stifle, hamstring, hip, and gluteal muscles to propel forward. Any imbalance in the hooves is going to alter these biomechan-ics and can lead to lameness, said Turner. He then described three of the most common rear hoof imbalances: Broken Hoof-Pastern Axis In any foot the front (dorsal) hoof wall should align with the pastern. In the rear feet this axis can change for many reasons, said Turner, but often because of age-related suspensory ligament weakness in older horses with hyperextended fetlock joints. It can also occur if the horse is placing his hind feet farther under his body to compensate for painful or underrun front feet, thus overloading his rear heels.Most commonly, Turner said, farriers and vets encounter a broken-back hoof-pastern axis, in which the hoof wall angle is lower than the pasterns. In the rear feet, this imbalance causes the hoof to stay on the ground longer than normal, he said. The strain on the deep flexor tendon will be markedly increased over normal before heel lift. This can lead to many lameness issues, the most serious of which is teno-synovitis (inflammation of the membrane surrounding the tendon sheath). A20 TheHorse.com/AAEP2017 AAEP Wrap-Up THE HORSEMarch 2018'