DSLD In Horses: Degenerative Suspensory Ligament Desmitis

One common problem for older horses is a condition in which the fetlocks become swollen, painful and inflamed and begin to drop. These are classic symptoms of degenerative suspensory ligament Desmitis or DSLD. This degenerative condition can be difficult or even impossible to deal with. In this article, we will explain the symptoms and nature of DSLD in horses and provide advice to help you cope. Read on to learn more.

DSLD Causes Systemic Problems

DSLD is a degenerative disease that most obviously affects the connective tissue of the lower limbs, but it’s important to understand that it also affects the whole horse.

Watch for these eight classic signs, symptoms and behaviors:

1. You may find that your horse wants to lie down a great deal and does not want to get up. While this may seem to be colic, be careful not to misdiagnose it.

2. Your horse may change his gait and move in a stiff manner and/or shift his weight to land toe first rather than heel first.

3. Your horse may become unstable when moving about or even when standing still. Symptoms may resemble a neurological disorder. In advanced stages, symptoms are obvious as the horse moves around with difficulty. In the late stages of this disease, your horse will be completely unsound.

4. Your horse may take up a post-legged stance in his hind legs, and his hocks may appear to be straight up-and-down rather than gracefully curved. He may trip, stumble and display varying degrees of lameness.

5. Swelling and heat in the fetlocks of the back legs is common, but this symptom may also occur in all four legs.

6. In advanced stages, the disease may cause pasterns to be parallel to the ground when weight-bearing.

7. The flexor tendons and suspensory ligaments may be quite painful when flexed and upon palpation. When you palpate these ligaments, you may find lumpy areas and hard, fibrous growths. This is because of calcification. Alternately, you may find mushy, soft, hot tissue. This is inflamed tissue affected by edema or water retention.

8. Horses in pain may seek relief by digging holes and then standing with toes pointed into the hole.

Degenerative Suspensory Ligament Desmitis

What Causes DSLD?

Initially, researchers believed that horses who had DSLD were developing an abnormal type of protein (proteoglycans) within the suspensory ligaments and in tissues throughout the body. When this was the belief, this disease was called equine systemic proteoglycans accumulation or ESPA.

As more research has been done, this theory has fallen out of favor and is no longer accepted. New research indicates that horses who have DSLD experience abnormal healing processes within the suspensory ligaments.

This means that the wear and tear that goes along with normal every day exercise creates an unusual amount of trauma (or micro trauma) within the suspensory ligaments.

Normally, a horse will produce more cells and create more collagen fibers to efficiently repair everyday wear and tear. Horses who have DSLD do not go through this process.

Instead they convert another type of cell which produces cartilage. This results in abnormal tissue inside of the ligaments that cannot stretch and extend, so the end result is breakdown.

Even with this information, full understanding of the cause is elusive. Many believe that the problem is genetic, and still others believe that it is environmental. It’s likely that it’s a combination of both, meaning that horses of certain types may succumb to environmental circumstances more easily than others.

This disease is most commonly seen in:

• Quarter Horses
• Thoroughbreds
• Peruvian Pasos
• Paso Crosses
• Saddlebreds
• Arabians

Unfortunately, no genetic marker has been identified, so it is not possible to do genetic testing to predict whether or not a horse may potentially develop this disease. It is generally accepted that if a horse does develop DSLD, it should naturally not be bred because every effort must be made to prevent the spread of this debilitating disease.

Equine DSLD-ESPA

What Can Be Done?

In the early stages, a clear diagnosis cannot be made without testing. Your veterinarian will want to perform an ultrasonographic evaluation. This will give you a clear picture of the type and causes of the enlargement in the fetlocks . Furthermore it will reveal details of the irregular fiber patterns, tearing of collagen fibers and calcified growths on the ligaments.

If caught early, you can manage this condition with lifestyle changes and environmental adaptations. This is the best that can be hoped for as there is no cure for DSLD.

1. Engage A Skilled Farrier

Some methods of coping include therapeutic farrier work and shoeing to help support the damaged limbs. Look for a farrier who knows how to safely trim the toe short allowing for easy breakover.

Your horse’s hooves should be properly balanced both side-to-side and front-to-back. Providing a heel wedge and using bar shoes can help to support your horse’s legs and relieve tense suspensory ligaments.

At the outset, your farrier should apply a high wedge, especially if the disease has already progressed to a severe stage. Once some relief has been attained, the height of the wedge can be brought down gradually until your horse is able to obtain relief from the use of normal wedge pads.

Good farrier work can provide dramatic and immediate relief for the pain your horses suffering.

2. Use Supplements & Medications

In addition to therapeutic hoof care (check our thrush treatment advice), dietary supplements can also help relieve inflammation and pain. Methyl sulfonyl methane (MSM) can help restore flexibility.

Phenylbutazone (bute) is a non-steroidal anti-inflammatory (NSAID) that can be used as needed for pain management, but it should not be used in an ongoing manner because this can result in ulcers.

Bute can be very helpful initially (especially after your horse has just been fitted with therapeutic shoes) to address acute pain. Previcox or firocoxib is another NSAID that works in a manner similar to bute, but it doesn’t tend to cause gastrointestinal problems the way that bute does.

3. Keep Moving

While you might think that a horse in pain would need plenty of stall rest, this isn’t true with DSLD. Inactivity will just cause more stiffness and lameness.

When your horse is first fitted with therapeutic or magnetic shoes and as adjustments are being made, you may want to minimize turnout time; however, once your horse is properly fitted with good shoes and is accustomed to them you should increase turnout.

How Debilitating Is DSLD?

Keep in mind that horses with DSLD are not sound and should not be ridden. These horses become strictly companion animals or pasture ornaments.

Unlike in the old days when an unsound horse was good for nothing, these days a beloved companion animal can continue to live a happy life and be a valued member of your family even with DSLD.

Working closely with your vet and your farrier, you can give your horse a happy life and enjoy his companionship for many years to come.