Page 137 - Speedhorse April 2019

tissue grew with the foal as he was running and playing, evolving with early training into what it had to do. With a healing injury, you have this new tissue that you’ve either regenerated or healed from surgery and if you ask the horse to immediately go back to being an athlete, often that tissue is more juvenile and not as strong. It has to be trained as it heals.” It can take a bit of time to accomplish this.
For many years we’ve known, from work- ing with racehorses, that bones condition
to what they do for a living every day. For instance, if a two-year-old racehorse goes
to the track and you x-ray his front cannon bones before he is working into his training program, and then again after he is well into training, you find obvious thickening in the wall of the cannon bone from the training. It will grow to three times its normal thickness in response to the work, modeling to its pres- ent use and stresses.
The trainer walks a fine line trying to
give the horse enough work to stress the bone enough to strengthen it without stressing it
so much that it becomes damaged. “If you overwork the horse, the bone won’t remodel properly and you’ll see bucked shins or cracks that may lead to breakdown injuries later on. Modeling is the term for a bone that is adapting in a normal fashion from a non-athletic bone
to an athletic bone. Remodeling usually means a pathologic condition of a bone responding to some kind of injury,” he explains.
“We’ve known for many years that bones model and remodel as the horse is conditioned with exercise. Bones, ligaments and tendons
are all living structures. The horse’s skeleton is not like the frame of a house that you build and then put the covering over the top and it’s solid. The skeleton is a living frame, so it adapts to stress and injury and attempts to strengthen itself,” says Easter.
“Even back in the early days we also realized that suspensory ligaments and the ligaments
of young horses when they first started training would model and condition to what the horse had to do every day as a high-level athlete. The rehab research in recent years has proven this to be true. We think of a healed injury as new or juvenile tissue, and it has to be trained to do what the rest of that horse could do before the injury in order for it to function properly,” he says.
Sometimes this is a painful stage and can lead owners/trainers to think the therapy was a failure. “The horse still looks lame, and if you don’t know that you need to go through the proper processes and start slowly and do all the various things we need to do to train the new tissue, people may assume that the surgery or treatment procedure didn’t work. The horse is still lame, so they give up on it,” Easter says.
Rehab is essential to deal with severe injury to ligaments and tendons. Today, we don’t even consider treating that horse and putting it back into normal exercise without some kind of rehab program. “This might range from hand walking for a while, then walking under saddle, then going to a gradual increase in work—15 minutes of walking, 5 minutes of long trotting, then increasing the long trotting by 5 more minutes each week—until the horse is doing an extended amount of trotting, and then adding the lope.”
This regime often works well for rehab
after minor injuries or for horses whose owners can’t afford a more extensive rehab program
or horses that are in a lesser degree of work. “Rehab goes all the way from that kind of minimal program to a more extensive regime in which horses are free swimming or working on an underwater treadmill. The underwater treadmill more effectively mimics exercise that a horse normally does and puts a little bit of load on the skeletal structure, depending on how much buoyancy there is. On a treadmill in water there is not nearly as much concussion, but it enables the limbs to have a little concus- sion and move in a normal fashion, as if they were working on ground.”
After you start working the horse on the underwater treadmill, you can slowly decrease the water level as the horse makes progress, gradually adding more concussion in a very gentle, mild way. You can thus ease the horse back into work.
“For a severe injury, where you want to get some movement in the leg, or after something like resecting an annular ligament, which
is similar to resolving human carpal tunnel syndrome, when the horse has adhesions in
the canal behind the fetlock, the underwater treadmill can be helpful in getting more range of motion with low stress. We cut that adhesion loose and it’s sore so the horse can’t sustain much weight on that limb, yet we need the horse mov- ing the tendons back and forth in that sheath. As soon as the stitches are out and the surgical wound is healed enough to be resistant to water, we get the horse moving again in the underwater treadmill to regain range of motion without loading the leg so much,” he says.
Cold therapy is also useful for rehab, to help reduce inflammation. “Rehab involves inflam- matory responses because we are training
tissue and have to push it to the edge. A rule
of thumb to keep in mind for damaged tissue in humans or horses is that it is only going to heal to the stage of what it is being asked to do every day. If you want to heal enough to just be a couch potato, you don’t have to do much rehab. You can break your leg and heal it back to where you can sit all day. But if you are a marathon runner, or a horse that races, you need to train those injuries all the way back to that level to call it a success,” says Easter.
“Bone only stays as strong as what it is asked to do every day. It is always in a state of flux, weakening and strengthening. If you stop exer- cising, it weakens. This is one of the reasons
we have to leg horses back up after they’ve been in a rest period. If there’s an orthopedic injury, whether bone, tendon or ligament, when it
is in healing phase, the body is geared up for
The underwater treadmill mimics normal exercise and puts less load on the skeletal structure due to the buoyancy of the water. There is not nearly as much concussion and the limbs move in a normal fashion as if they were working on ground.
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EQUINE HEALTH