A year or so ago, I wrote about DSLD and today I saw this update, so I’d like to present it, in case any of you need this information and missed it.
DSLD is thought to run in families. It’s somewhat somewhat similar to some hereditary diseases that affect connective and musculoskeletal tissues in people such as Marfan syndrome (on a completely unrelated note, some people think that Abraham Lincoln may have had Marfan syndrome), or Ehlers-Danlos syndrome. Like these diseases, DSLD ultimately leads to breakdown of connective tissue.
As the supporting connective tissues of the limb break down in affected horses, you might see any number of clinical signs. The fetlocks drop towards the ground, pasterns move towards horizontal, and hocks and stifles straighten out. Sometimes affected horses have a hard time
standing when the opposite leg is held up due to the pain. You can sometimes feel enlargement and/or hardening of any or all of the suspensory ligaments (even though the problem is horse-wide). DSLD frequently leads to persistent, incurable lameness, especially of the hind limbs. The disease is slow, and progressive, and affected horses are often ultimately euthanized due to breakdown of their limbs – a horse that’s walking on the ground with its fetlocks is not pretty to see.
Diagnosis of DSLD is typically based on family or breed history (horses that have DSLD tend to breed more horses with DSLD), clinical examination of the horse with sinking fetlocks, and ultrasonography of the affected ligament(s), which shows mostly that the tissues are breaking down, but for no specific reason. In fact, up until a few years ago, the final diagnosis of DSLD was always pretty much a matter of waiting and seeing what happened to the horse – if they got really bad, and nobody could do anything about it, bingo, the diagnosis was made (albeit a bit late).
In 2006, however, some very clever investigators at the University of Georgia started to unravel the mysteries of the disease. As good scientists like to do, particularly when they’ve found something really revolutionary (but even when they are just trying to get tenure), they’ve published their findings.
CLICK HERE to see the article, “Degenerative suspensory ligament desmitis as a systemic disorder characterized by proteoglycan accumulation,” published from the Department of Large Animal Medicine at the College of Veterinary Medicine at the University of Georgia.
Out of this work came a technique to suggest a diagnosis for DSLD, based on biopsy of the nuchal ligament, a big, tough ligament that connects the poll to the withers, and helps hold the horse’s head an neck in position. Don’t worry, your veterinarian can take a small piece of the ligament, and your horse will still be able to hold up his head. For information on this, have your veterinarian contact:
Dr. Jaroslava Halper, Department of Pathology
College of Veterinary Medicine, The University of Georgia
Athens, GA 30602-7388
Now for the really bad news; there is currently no cure for DSLD. Of course, the lack of a cure should stop absolutely no one from trying to find a cure, and it doesn’t even stop a few people from claiming that they do have a cure. SupportGroup.3Internet support groups have formed, and various treatments have been proposed, but nothing has really been shown to slow down the disease – and certainly not cure it – in good studies (trust me, if there was anything that really worked to cure a horse of DSLD, everyone would be using it).
The typical treatment for a DSLD horse is based on things that people think that the ought to do, such as “supporting” the limb by means of various shoeing and bandaging techniques, reduction in exercise, and pain relievers, as needed. More novel therapies, and various supplements, have also been proposed. Unfortunately, ultimately no treatment has been shown to be effective in stopping disease progression (and since you don’t know how the disease will progress in any one horse, it’s hard to say how it might have done without the treatment that you think is working).
The best way to deal with DSLD is to try to avoid it. If you’re purchasing a horse from an affected breed, it wouldn’t be a bad idea to look into its genetic history (if possible). Ultimately, selective breeding and identification of affected strains – as has occurred with HYPP – will be needed to eliminate this problem.