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Kirsten's e-mail to me began, "Well, I had the worst day and the best day of my life yesterday."
She was referring to Albert, the 22-year-old Thoroughbred gelding who had been her show horse, pleasure horse, and best friend for some 18 years. Kirsten Bech and I were childhood friends reunited by the Internet and a mutual love of horses, and over the past few months she had been acquainting me with the strange and discouraging story of Albert, who had been given to her by her parents when she was 16.
"Albert was five when Mom and Dad bought him for me," wrote Kirsten, "but I'd been riding him since he was four. We didn't have enough cash to purchase him, so half of the payment consisted of a table and four chairs from Mom and Dad's furniture store!
Kirsten and Albert had what she calls "a semi-successful run at the shows", garnering many favorable comments about his elegant way of moving from dressage judges. College intervened with their showing plans after three years, but Albert eventually made his way out to East Lansing, Michigan, to join his owner. There, Kirsten's new coaches, Sharon and Jim Rowe, first began to notice that there was something wrong with Albert's gait. "We think," says Kirsten, "that other judges and trainers had been so "wowed" by his stride (he overstepped almost two feet at the trot) that they didn't notice he was tipping his (hind) toes down before picking his feet up. He also had trouble making tight turns, like turning around in the barn aisle." Still, it was nothing anyone could really put their finger on.
After graduating from Michigan State University with a degree in communication and market
research, Kirsten moved to Arizona, where Albert again joined her after being leased to one of the
Rowe's students for a year. It soon became obvious that the hind toe-dragging was becoming worse.
Concerned, she had veterinarians run him through a battery of tests.
The difficulty the horse had in turning tight corners pointed to damage to the nervous system, so that's where the examination started. "Everyone was amazed," she remembers, "at how well he did on some of the maneuvers used to test for neurological damage (such as backing on an incline and walking with his head turned to one side), but the vets still said he must have some kind of lesion that caused the 'funkiness' in his gait." For lack of any better diagnosis, Albert was labeled a wobbler. ("Wobblers" suffer from a neurological disorder that affects their coordination. Stemming from damage to the spinal cord in the neck, wobbling can originate from an injury, protozoal infection, or nutritionally-induced osteochondritis of the spinal vertebrae, which pinches the spinal cord.)
Baffled and discouraged, Kirsten gave up any hope of showing Albert again, and relegated him to the role of occasional trail-riding companion. In an effort to help his condition, she tried bar shoes and shoes with rolled toes, sports massage, chiropractic, acupuncture, applied kinesiology, and Tellington-Jones techniques for spatial awareness.... all of which, she says, made him somewhat more comfortable but did nothing to improve his gait. He continued to drag his toes, and his hind fetlocks, it seemed, were gradually dropping towards the ground. Kirsten gave up riding him altogether when he became very back-sore after a trail ride. "My vet thought that the original condition had worsened and it was time for him to 'rest'. That's when Albert became the foal sitter extraordinaire," she says.
At Gayle Faber's farm in Queen Creek, Arizona, Albert seemed to be in only moderate discomfort as he minded Gayle's two weanlings. But his mystery condition continued to progress. Never an easy keeper, he dropped further weight in his teens, and had great trouble holding his feet up for the farrier. Kirsten, meanwhile, had followed a job opportunity to Cincinnati, Ohio and acquired a young Arabian mare, Dea, to be her new dressage prospect... but she continued to keep in close touch with Gayle as to Albert's well-being.
"Gayle called me one day early in May, 1996, and said Albert was in so much pain that his knees had buckled when she had tried to put a brush to him. The horse had almost collapsed in the barn aisle. I figured his neurological condition had worsened to the point where it was time for him to move on."
Kirsten made the heart-wrenching decision to put Albert down. But as she wanted to be there to say good-bye to her old friend, she asked Gayle to find a local veterinarian with a specialty in acupuncture and chiropractic, who might be able to give Albert some pain relief until she could make the trip to Arizona the following weekend.
The veterinarian Gayle found was Jan Young, DVM, based in Black Canyon City, Arizona. Dr. Young agreed to come out and examine Albert, and consulted with Kirsten soon afterwards by phone. "I know you said this horse had a neurological condition," she said, "but I did the standard neuro battery on him, and he did quite well. Based on his conformation and the way he's compensating, I'd say that it isn't a neurological condition at all.... it's degenerative suspensory ligament desmitis."
DSLD, Dr. Young explained, is a relatively unknown disorder on which very little has been published. By lucky coincidence, she is one of the few vets in the country who has investigated this strange condition... and said that when she saw Albert, everything "clicked". "She described to me the typical way horses with DSLD typically move and behave, and it was like she was telling me his life story after knowing him for 20 minutes," says Kirsten.
In a paper funded by the Equine Trust Foundation, Dr. Young notes that DSLD "is a syndrome being recognized with greater frequency. First recognized at UC/Davis in the early 1980's, few reports exist in the veterinary literature." Dr. Young saw her first case in 1986, "and at the time, I didn't know what I was looking at. Now I see one or two cases a month, and I suspect that for every one I do see, there are nine out there that are undiagnosed."
At the heart of DSLD is an abnormal healing process in the suspensory ligaments. Horses with DSLD typically have an obscure lameness that develops over time, and exhibit pain (even grunting audibly) when the suspensories are palpated. As the condition progresses, there may be filling in the fetlock joints (windpuffs), an exaggerated dropping of the fetlocks (especially noticeable when the horse is in motion) and a gradual straightening of the stifle and hock angle in the hind legs. Pasterns eventually become horizontal and high ringbone (arthritis of the pastern joint), as a secondary symptom, is fairly common.
Some DSLD horses become resistant to having their feet picked up, making shoeing an ordeal -- Dr. Young describes horses who will stand with their legs snatched up under their bellies for minutes at a time. Others will dig holes in soft footing so they can rest the affected legs in a position with the toes down and heels elevated. On hard surfaces, horses may rock back and forth, relieving one leg and then the other.
One of the interesting things about DSLD is that is always bilateral -- that is, it affects both front legs, both hind legs, or all four. No other suspensory injury matches this pattern of distribution, notes Dr. Young. This helps to distinguish it from other conditions, but can also disguise lameness until it is quite progressive.
Dr. Roy Pool, of UC/Davis, studied over 30 DSLD cases in 1992 and found a consistent pattern to the condition. He hypothesizes that at some point in the life of a predisposed horse, a previously normal suspensory ligaments begin to fail to resist the everyday forces exerted during exercise. Normal ligament tissue repairs the day-to-day 'microtraumas' of ridden work with the help of fibroblasts (cells that produce collagen), bridging the damage before the ligament can tear and cause lameness, but in DSLD horses, something goes wrong with the process. Instead of new collagen fibres being laid down in line with the stresses on the ligaments, the fibroblasts seem to 'change their job description' (through a process not yet fully understood) and become chondrocytes instead. Chondrocytes are cartilage-producing cells, and as cartilage is laid down in the suspensories, the ligaments can't restore themselves to normal tissue strength or elasticity. Without the ability to stretch, even the strain of normal weight-bearing on the limbs becomes too much, and over time, the ligaments lengthen and break down.
The results of this faulty healing process can be felt when the suspensories are palpated. A thickening or hardening of the mid-body of the ligament or the suspensory branches is typical, and ultrasound imaging easily confirms the diagnosis. An ultrasound image will show an enlarged circumference of the ligament (greater than 1.2 cm), tearing of the fibres, and a poor fibre pattern, with a characteristic "mottled" appearance. "Over time," notes Dr. Young, "the fibres get arrayed in this starburst pattern
-- a unique kind of flare you don't see with any other condition." Radiographs will reveal a lowering of the sesamoid bones relative to the fetlock joint (sometimes even ending up 'underneath' the fetlock in advanced cases) and, sometimes, mineralization in the soft tissue areas of the suspensory branches. But Dr. Young feels that nuclear scintigraphy may be the best way to diagnose DSLD "You'll see hot spots in both the soft and hard tissue, in a unique bilateral distribution," she says.
Most often occurring in paso-gaited breeds (where the lameness may be "lost in the gait"), DSLD has also been diagnosed in Arabians, Quarter Horses, and Saddlebreds, and seems to be more prevalent in certain bloodlines, implying there may be a genetic predisposition. Attempts to find a genetic marker from blood samples of affected horses has so far been thwarted, however, by breeders unwilling to cooperate with full disclosure of the animals' pedigrees or a list of related horses who also showed symptoms of DSLD.
No-one yet knows what triggers the faulty healing process, why the suspensory ligaments seem to be singled out (the condition has been noted in the distal sesamoid ligaments as well, but so far in only two known cases), or how we might be able to reverse the process. Eventually, severe cases of DSLD may progress to the point where the horse is only comfortable when lying down, and when standing, will be reluctant to move even for food and water. DSLD is progressive and irreversible, and as the
question of heredity is unanswered at this point, Dr. Young recommends that any horse who has been diagnosed with the condition not be bred.
But there was good news for Albert: with some changes to his farriery and management, Dr. Young felt he could be made sound enough for light riding again.
"I'm so excited," said Kirsten's e-mail to me that evening, "and so is Gayle. We're really looking forward to proceeding with the treatment. I started out in the morning thinking I would have to put Albert down, and now he may have a new lease on life. I can't believe this poor horse has been misdiagnosed for 17 years!"
The first step in Albert's rehabilitation was to add methyl sulfonyl methane, or MSM, to Albert's diet. MSM, a tasteless white powder chemically related to DMSO (dimethyl sulfoxide), appears to help restore flexibility to soft tissues, and Gayle noted an improvement in the 'hang time' of Albert's hind toes after only a week on the supplement. The second, and most important step, was to boost Albert's heels to relieve pressure on his hind suspensories. Specially designed bar shoes with 'high heels', providing an elevation of about two inches, were prescribed. "These usually bring instant relief," says Dr. Young. "After six months, you can gradually bring it down and use wedge pads instead." Farrier Lisa Barnes worked closely with Dr. Young to custom-design and construct Albert's special "Patton" shoes.
Following Dr. Young's instructions, Gayle Faber kept Albert confined to his stall for two weeks after the new shoes were applied in May, 1996. "You could see that he was immediately more comfortable," she says, "but about three days after the shoes were put on, he was sore --I think from the strain of the new position of his hind legs. I put him on bute for 24 hours, and after that, he was fine. In fact, the shoes stayed on beautifully, and while they looked pretty unusual, the difference in the horse was dramatic. After two weeks, I turned him out by himself, and it was the first time I'd ever seen him move properly. He was gorgeous! He felt so good, he was bucking and rearing all over the paddock -- it brought tears to my eyes. For the first time, I could see the beautiful horse Kirsten always knew was there."
The only downside of Albert's new shoes was that Gayle was hesitant to turn him out in company, for fear the shoes would do significant damage if he were to kick another horse. The heels of the shoes also provided an easy opportunity for Albert to snag a foot on the fencing, so she kept a close eye on him while he was turned out; fortunately, he never got himself into trouble. By December, 1996, Dr. Young judged Albert sufficiently improved to graduate to the next step: ordinary shoes with wedge pads. Gayle combed the local feed stores for the highest wedges she could find, and farrier Lisa Barnes ended up stacking two pads on each of Albert's hind feet. The resulting 'high heel' was quite a bit lower than the Patton shoes, and Gayle repeated the routine of two weeks of stall rest, and a little bute when Albert seemed uncomfortable on the third day. But the horse continued to move soundly, and with his safer footwear, is now back out with the group, babysitting Gayle's yearling and enjoying the company of her twentysomething broodmare.
Gayle notes that the difference in the conformation of his hind fetlocks is noticeable. "Before, his pasterns were almost horizontal...now, you can see how the angle has been boosted." She also remarks on the change in his general condition. "The combination of the MSM, and being pain-free, seems to help him get better value out of his feed. For the first time since I've had him, his coat is bright, he's carrying good weight -- in fact, I've had to cut his feed back! -- and he doesn't look like a 22-year-old horse. To watch him out in the field now, you'd swear he wasn't older than 12. It's just been a miracle."
As for Kirsten, she has been given the green light by Dr. Young to try riding Albert again, for the first time in over four years -- though Gayle warns that the gelding is now feeling so feisty that Kirsten may have her hands full! A trip to Arizona was postponed due to the ill health of a grandparent, but she hopes to see her old friend soon... and perhaps even bring him back to Cincinnati with her this summer. For Albert, the diagnosis of DSLD has been anything but a death sentence.
Post Script: Albert moved to Cincinnati in the spring.
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