Any horse can sustain an injury at any time however showjumping, and the stresses and strains that come with it, can make certain injuries more common.
Showjumping puts huge amounts of stress on the joints and the soft tissues (tendons and ligaments) that support the limbs and feet during both push-off and landing phases. Speed and tight turns also increases the forces that are put through the limbs, so risks are higher for jumpers who are against the clock. Many showjumping horses compete all year-round and we know that with repetitive stress, minor damage can build up in ligaments, tendons and joints making these structures much more vulnerable to a more serious injury. If we now look at some specific injuries in more detail;
Suspensory Ligament Injuries
The Suspensory Ligament acts like an elastic sling, supporting the fetlock joint as it sinks under weight and helping to return the joint to normal when the weight comes off. The ligament starts just below the knee (or hock), splits into two branches that attach onto small bones (the sesamoids at the fetlock and ends up in the pastern.
If the pressures on the ligaments become too great, or through repetitive strain, the tough fibers that make up the ligament may break or tear. Although fibers can tear at any point on the ligament, injuries near the top (proximal) of the cannon bone are most commonly seen. These injuries may be mild with just a few damaged fibers, but in severe cases, the ligament may tear and can even damage the bone where it is attached to. The horse may show up suddenly lame, but usually damage builds up as a result of recurring stress. Identifying the problem as early as possible gives the horse the best chance of recovery. Early detection isn’t always easy with suspensory injuries. A horse with a mild injury may only be very slightly lame and may show very little or no swelling/sensitivity at the injury site.
Diagnosis is usually made with local nerve blocks and detailed lameness examinations. An ultrasound scan will show the exact site and the degree of the injury to the ligament. Every case is different, so your vet will help you work out a treatment plan that suits your horse’s injury. Treatment usually includes:
· Anti-inflammatory treatment including cold therapy and a nonsteroidal anti-inflammatory drug, such as phenylbutazone (Bute).
· A period of rest to allow healing to occur.
· Rest is followed by walking exercise once inflammation has reduced to encourage further healing.
· Gradual return to exercise following a program that eases the horse back into work over several months, using ultrasound to monitor the ligament healing.
· Selected cases are best treated by surgery
Other therapies, such as extracorporeal shockwave therapy, or stem cells or platelet-rich plasma injected into the injured area can help improve the prognosis by increasing the quality of healing.
The healing process should not be rushed. Re-injury is a risk even after healing because scar tissue that forms isn’t quite as strong as the original ligament tissue.
Front Feet Pain
Horses front feet take huge strains on landing after a jump. Structures within the hoof capsule work in unison to absorb the shock. The coffin joint and navicular bone dissipate these force. Ligaments that hold the joint together continuously stretch then spring back, as does the deep digital flexor tendon, which runs behind the joint and supports the navicular bone.
Horses feet are designed to handle great forces but jumping fence after fence takes its toll.
Common problems include:
· Strains and tears in the deep digital flexor tendon or the ligaments in the foot
· Inflammation in the coffin joint (osteoarthritis)
· Deep tissue or bone bruising
· Inflammation and degeneration of the navicular bone and associated structures.
· A combination of 2 or more of these
Because the hoof capsule encases the injured structures it is unusual to see or feel any swellings, however the affected foot may be warm and have a strong digital pulse. Often these problems involve both front feet, so the horse may not appear obviously lame. The horse may begin to move with a shorter stride length. They may be lame and improve with a period of rest, but be sore again when put back into work. The horse may also shift weight from one foot to the other when standing resting.
A lameness exam and diagnostic nerve blocks will help in the diagnosis of the problem. X-rays can show any bone damage, but they don’t show soft-tissue injuries. The best diagnostic tool is MRI as this shows all of the internal structures but is expensive to perform.
· A tendon or ligament injury usually requires a long period of rest. A recovery program will be similar to that described above for a suspensory injury.
· Inflammation or osteoarthritis of the coffin joint and/or the navicular bone may respond to injections of corticosteroids and remedial shoeing
· Areas of deep bruising need rest and anti-inflammatory treatment. These injuries aren’t as serious. Healing can take weeks or months depending on the degree of damage caused.
Obviously, a horse with a mild injury has the best chance of recovery. Good farriery is essential to keep the horse comfortable, regardless of what structures are involved. It is so important to keep the horses feet trimmed at the correct angle and accurate shoe placement and balance, so the bones are properly aligned and the foot breaks over correctly.
Showjumping horses are especially prone to joint problems. Common sites include the hocks, stifles and fetlocks but Osteoarthritis (OA) can develop in any joint that comes under stress when the horse works. Chronic inflammation in the joint from injury or simple wear and tear sets off a destructive chain of events. The oily fluid that lubricates the joint becomes thin and watery, affecting the cartilage that cushions the working surfaces of the joint. Cartilage may start to wear away as more inflammation continues and eventually underlying bone responds by remodeling.
Joint problems often come on gradually. At first the horse may be mildly sore or stiff in its movement especially at the start of work. Over time this may worsen and begin to affect performance over jumps. There may be heat or swelling present in the affected joint(s).
A lameness exam will help diagnose OA. X-rays can show damage to bone and cartilage, but often by the time this damage shows up the osteoarthritic process may be well under way. Damage to a joint cannot be reversed, but it is possible to slow the progress of the disease by managing inflammation. Anti-inflammatory medications like phenylbutazone (bute) can help the horse when a flare-up occurs, but for long-term management other options include;
· Joint injections of corticosteroids and hyaluronic acid help reduce inflammation and slow damage.
· Many feed supplements claim to protect joints from inflammation, but what little research exists is inconclusive. If these products help, they may be most useful in the early stages of inflammation. They are unlikely to help a severe case.
· Adjusted work levels can help. Frequent low intensity exercise is good for joint health. Increasing the amount of turnout and long warm-ups can help.
OA generally worsens over time, putting limits on the horse’s career. Careful management can keep the horse in competition, however eventually there maybe a need to switch to easier work.