The trophy rested on a mantel in their family room, beside an oil painting. It was elegant, though small. Roy Jackson easily lifted it down and, in the thin gray light of winter, offered it for closer admiration. Engraved in gold was an event: 132nd Kentucky Derby. A venue: Churchill Downs. A date: May 6, 2006. And: Won By Barbaro.

Roy and his wife, Gretchen, live on 190 acres of Wyeth country in southeastern Pennsylvania, up a sinuous driveway that leads to a house on a knoll. They own sheep, cats, cows and dogs, but mostly they own horses. In more than 30 years, they had never had a superlative racer, never had a horse in a Kentucky Derby nor even been spectators at one until that date etched on the trophy. As Barbaro shifted into an unworldly gear in the far turn that Saturday and began flying as if his 19 competitors had been flash-frozen, Gretchen thought, "Oh my gosh, he really is that good."

Victory meant that he had run six races and had yet to lose. Grass (three wins) or dirt (three), the surface didn't matter. The next jewels of the Triple Crown, the Preakness and the Belmont Stakes, beckoned. Maybe after that, the Jacksons would take him to England to race, just for fun.

Now their 3-year-old colt was living in a veterinary hospital three miles away. He had been there since bones in his right hind leg blew apart in the opening seconds of the Preakness, May 20, 2006. It is mere coincidence, nothing more, that the Jacksons are neighbors of the University of Pennsylvania's New Bolton Center. They did not buy their farm in 1978 to ensure easy visits to sick horses. It just worked out that way. Each day since the accident, they gathered grass from their fields and drove down a two-lane road to the intensive care unit. The home-picked meals were not an official medical regime. They helped keep the bond intact.

Gretchen, 69, and Roy, 70, have known each other since their high-school days in Philadelphia, and finding a more gracious couple would take a long search. As they sat in the family room on a January morning, fenced fields filled the view through a wall of windows. Another wall held a lithograph of six hounds. No one knows to whom the dogs once belonged, but the image has been in Roy's family a while. Imprinted on the lithograph beneath each hound's face is a name. The one farthest right reads "Barbaro."

"He is always in my heart," Gretchen said of the hound's namesake. But seeing him each day was "really, really difficult." He was almost unfailingly alert and playfully nippy, still magnificent, if thinner than before the accident. But looking at the world through a hospital window was not a Thoroughbred's life.

"My thing is," Gretchen said, "when I walk into this house, I let all the dogs out. I let them all run. I just love...."

She stopped, searching for a word.

Freedom?

"Yes. I love it. It's what they're meant to do. Run. Hunt. I don't worry about them at all. And to see a horse cooped up in a stall, it sort of really bothers me. But what would bother me worse is if we don't give him a shot."

Nearly 32 years ago, a champion filly named Ruffian snapped her right front leg on the backstretch at Belmont Park on Long Island, New York, during a heralded one-on-one match race with Derby winner Foolish Pleasure. In the genteel euphemism of racing, Ruffian "broke down." Surgeons labored, but euthanized her within hours.

Today, swift death after such a severe injury is still the fate of many, many racehorses. By virtue of size and anatomy, they make challenging patients, and healing them often costs more than they are worth or their owners can afford. But surgery, anesthesia, infection control and recovery have raced far forward since Ruffian's death in 1975. The public may see Barbaro merely as a compelling narrative. A model athlete, he was nearing his sport's pinnacle when, in a finger snap, the quest became not more trophies but survival. Yet Barbaro also represents bigger things. He is the greatest illustration of the advancements of equine medicine. He also highlights how far it needs to go.

There remains an insidious threat to the health of all horses, not just Thoroughbreds. It is a hoof disease called laminitis. Science has not fully parsed its workings, much less found a pill to ward it off. Research money is scant, even though a federal study suggests tens of thousands of horses have laminitis each year and several thousand die from it. A horse with a broken limb is especially susceptible to it. "It is the Achilles' heel of all these repairs we do," said Wayne McIlwraith, a professor of equine surgery at Colorado State University.

After the accident, New Bolton's medical skill gave Barbaro a chance to live, and by January his broken leg was healed, though not perfectly. But by then, laminitis was trumping medicine.

With the 2006 Preakness having just concluded, a veterinarian named Dan Dreyfuss stood inside Stall 40 at Pimlico Race Course in Baltimore. He was waiting for images to materialize on a computer he had set atop a straw bale. Or maybe it wasn't a straw bale. He cannot recall all the details of those intense moments. Stripped of saddle and silks, Barbaro stood diagonally in Stall 40, which on Preakness Day is offered to the reigning Kentucky Derby winner.

The colt was the least anxious mammal present. "He stood there like a statue," Dreyfuss said. Barbaro seemed calmly aware that he was grievously wounded, because he was keeping weight off the injured leg, now braced with an aluminum splint called a Kimzey. Any horse person would know the leg was broken near the fetlock, a joint just above the hoof, but only X-rays would tell how severely.

Dreyfuss, a private practitioner in Maryland, had never seen Barbaro up close until earlier that day. Trainers often hire a local veterinarian when they bring a horse to a track, and Barbaro's trainer, Michael Matz, had used Dreyfuss before. Having seen the leg break on a television in a hospitality tent, the doctor had started sprinting even as jockey Edgar Prado slowed Barbaro to a sickening walk as the field thundered ahead.

In the stall, in the straw, a technician was bent beneath the horse, moving a radiographic plate around the damaged leg, as Dreyfuss' partner, Nick Meittinis, snapped images with a hand-held X-ray machine. At the computer screen, black-and-white photos took shape, one after the other.

The pastern bone, below the fetlock joint, had dissolved into some two dozen pieces. The cannon bone, above the fetlock, had splintered. A sesamoid bone in back of the fetlock had cracked. Even a single break is bad. Barbaro was at the extreme end of the injury scale. "One look at that and you know you're in for an absolutely huge fight," Dreyfuss said.

A Thoroughbred weighs more than half a ton, and as he gallops, no more than two legs at a time absorb the shock of earthly contact at more than 35 miles per hour. Sue Stover, a professor at the University of California at Davis veterinary research laboratory, says that many runners, animal or human, wind up with microscopic bone damage because of the repetitive pounding of training and competition. Regularly, the body swaps such damaged tissue for new, but weak spots can develop if damage occurs faster than replacement.

That does not mean a bone will break. It means the risk of injury is higher. After examining sample tissue from racehorses that died or were euthanized after leg fractures, Stover's laboratory found that more than 90 percent had preexisting bone damage. Nor are fatalities the only threat, she said. Imagine a stable of 50 horses that race regularly. In three months, there might still be 50 horses, but a fifth will no longer be competing. Age or illness will have taken some, but muscular-skeletal injury will have sidelined the rest, at least temporarily. "It's huge, it's huge attrition," Stover said.

Nobody, certainly not a family on a Sunday outing, wants to see a mercy killing on the track. Nobody wants to lose a prized investment, either. Racing is a $10.7 billion-a-year business that employs 146,000 people, according to a 2005 study done for the American Horse Council. So there are reasons both humane and economic to reduce track fatalities, which average more than one a day in the United States and Canada.

One idea is to replace dirt track surfaces with more forgiving, man-made materials. The California Horse Racing Board, in fact, has ordered major Thoroughbred tracks in its state to switch to synthetic surfaces by January 1, 2008. But a dream solution involves finding an early-warning system. Researchers believe markers in the blood can telegraph whether a horse is experiencing risky bone damage, says McIlwraith of Colorado State. If so, the animal could be held out of training or competition until it heals. "We're not quite there yet," McIlwraith said, "but we're getting there."

No evidence exists that Barbaro had underlying bone damage. In fact, Matz, his trainer, was criticized before the Kentucky Derby for not running him enough to have him in top form. That complaint evaporated after Barbaro won by six and a half lengths, the biggest margin in 60 years.

Perhaps in the Preakness he did nothing more than take "a bad step," the phrase often heard after a horse breaks a leg. Or perhaps an incident that occurred just before the bell was a factor. Barbaro burst through his gate and had to be checked before being led back to his post position. No injury was found, but that doesn't guarantee that nothing was wrong. We might never know why, moments later, the skeletal structure of his lower leg failed massively.

After seeing the images in Stall 40, Dreyfuss told Matz and the Jacksons, who had gathered just outside, that the leg was "bad." Then he returned to Barbaro, ducked beneath him and took off the Kimzey splint. He unwound Barbaro's rundown bandage, the white legging horses wear as protection against abrasions. There was more that Dreyfuss needed to know.

Running his hands up and down the leg, he checked to see if bone splinters had pierced the skin. Incredibly, none had—a small piece of luck. An open wound would have meant that dirt and germs from the track were inside, creating a grave risk of infection. Then Dreyfuss checked circulation near the hoof. Without good blood flow to promote healing, the future would be very bleak. "I could feel a pulse," he said. Another good sign.

The doctor never considered putting Barbaro down. Nobody did. This was the Derby champion. And Dreyfuss knew the Jacksons by reputation as owners who cared. "I knew we were going to try to save this horse," Dreyfuss said. "No matter what."

He knew who would do the saving too.

Barbaro had been hurt only 82 miles from one of the best large-animal hospitals in the country, and from the very surgeon who had pioneered the use of a surgical device that would be central to Barbaro's salvation. Some 90 minutes after the Preakness, the horse was secured inside a trailer heading northeast to Kennett Square, Pennsylvania.

On a shelf in a nurse's room at the New Bolton Center is a framed photograph of the chief of large-animal surgery. Scrawled beneath is a caption: "He is as blunt as his crew cut." Dean W. Richardson, who is 53, can be intimidating—but is "a marshmallow" inside, Dreyfuss said. He can be hard—on himself as much as anyone. And his fan base among his peers is sizable. Midge Leitch, who supervised Richardson when he was a surgical intern at New Bolton, said he gives great speeches off the cuff, loves tools and loves solving the puzzles of surgery on massive animals.

Shortly before he performed a recent arthroscopic operation, Richardson entered a small conference room at New Bolton and tossed a hefty stack of mail on a table. "This is what I get," he said. Americans had been thanking him, offering home remedies and, in rare instances, urging him to euthanize Barbaro. He found the last sentiment odd: "Their knee-jerk reaction to any animal that's uncomfortable is to think they're doing them a favor by killing them."

If an injured animal can be helped to a life of quality and comfort, he said, "then I think going through a period of pain is something most of us, if we had our choice, we'd elect to go through." This is not the old era. Surgeons can do much more. "A situation like this, you get slapped in the face that people really don't know that we fix horses' broken legs on a pretty regular basis."

Not all broken legs. As much as anything, the decision usually comes down to money. Does an owner have thousands of dollars for surgery and recovery? Does the horse have value, economically and emotionally? Such judgments are intensely personal, not only with a horse but with anything. Some of us use our money to buy art, some to buy football season tickets, some to give to charity, some to save our dog or cat. Or horse.

In the Jacksons' case, Richardson said, "money's just not a limiting issue." Roy, a descendant of the Rockefellers, is a former owner of two minor-league baseball teams and a former president of three minor leagues, and Barbaro had just won $2 million at the Derby. And, Richardson said, "they love the horse. They truly love the horse."

The goal of Barbaro's surgery was not to enable him to compete again. His racing career was over. But if the leg could be rebuilt, he might pass happy days strolling pastures and producing little Barbaros. To reproduce, a stallion must be able to stand on his hind legs and mount a mare; artificial means are not allowed in Thoroughbred racing. Stud fees for a champion like Barbaro would be huge. But Gretchen Jackson's reasons seem simpler. She just wanted him to be a horse again, at least as much as possible. Barbaro had done a marvelous thing, won the Derby. He deserved a chance to live on, as long as his pain and discomfort during the rehabilitation effort did not become intolerable.

On Sunday, May 21, the day after the Preakness, a surgical team assembled in a New Bolton operating room. Richardson said he made no pep talk and laid out no plan. He knew what he would do. The surgery would not be groundbreaking; it would merely be immensely challenging.

Any operation to fix a horse's leg is more complex than fixing a human's. For one thing, horses are anesthetized while standing and promptly collapse, leaving a massive, limp animal to be moved around operating and recovery rooms. At New Bolton, slings suspended from ceiling monorails do the job.

Then, as anesthesia starts to wear off after surgery, a fearful or disoriented horse might flail his legs, striking the floor or walls and destroying the very repairs that have just been made. That is what happened to Ruffian in 1975. At New Bolton, a horse can awaken on a raft in a heated pool, his legs dangling below in glove-like rubber sleeves. If he flails, he hits nothing but warm water. Finally, after a horse is awake and calm, he cannot be put to bed while the leg heals. Lying for long periods hampers breathing, digestion and other functions. Very quickly, a horse must be able to do what seems counterintuitive: stand and put weight on a repaired limb.

In Barbaro's case, that would seem almost miraculous. Liberty Getman, a surgical resident who assisted Richardson in the operating room, said she was stunned that morning to see the X-rays. "I don't know that I've ever seen a leg look like that that anyone has thought of repairing. It was much worse than I had hoped."

But Richardson had an ally, a narrow, stainless-steel bar with 16 threaded screw holes. Inserting plates with screws beneath the skin to stabilize human bones is common, and it's been done as long as 35 years in horses. But in the past few years, Synthes Inc. of West Chester, Pennsylvania, has developed the locking compression plate (LCP), a particularly secure and effective type. No equine surgeon had more experience with it than Richardson.

Using an LCP about 12 inches long, as well as about a dozen independent screws and a cast on the outside, the veterinarian methodically reestablished a solid bone network in more than five hours of surgery. Steven Zedler, another surgical resident who assisted, said the process was a "piece-by-piece, step-by-step thing, ‘Yeah, I'll take that and screw it to that.'" Richardson had to fuse both the fetlock and pastern joints, though that would mean Barbaro would walk awkwardly. At no point, Richardson said, did he see any sign of preexisting bone damage. On the contrary, the staggering amount of breakage suggested "a very significant misstep."

No plate can hold the weight of a horse indefinitely by itself. And infection under and around it is always a threat. The hope was that the leg would heal and resume supporting Barbaro before either metal fatigue or infection became a problem. The overhead monorail took him to the recovery pool. In public comments during the next few days, Richardson made no promises. The horse had a fifty-fifty chance, no more. If those odds seemed low, Richardson was acutely aware that laminitis could undercut the surgical work.

For surgeons, is that prospect irritating?

"Irritating"? Richardson repeated, as if to say you're joking.

More like maddening.

On July 10, after weeks of good news about Barbaro's recovery, Roy Jackson telephoned his wife from an office he keeps near their home. He told her Richardson wanted them at New Bolton, immediately. Barbaro had laminitis as bad as a horse can have it. "To me, it was the kiss of death," Gretchen said. "So I went over there to say goodbye to him, basically."

A horse's feet are complex marvels, because the animal moves on its toes, like a ballerina. Each leg ends in a single digit called the coffin bone. That digit is surrounded by the hoof, which is the equivalent of a toenail that completely encircles the toe. In the middle, between coffin bone and hoof wall, are two layers of laminae.

Larry Bramlage, a former president of the American Association of Equine Practitioners and a surgeon at Rood & Riddle Equine Hospital in Lexington, Kentucky, likens laminae to a tiny forest of pines whose branches intertwine. They bind the coffin bone to the hoof wall, preventing the digit from shifting as the horse moves. Laminitis breaks that bond. The laminae start to give way, causing pain and discomfort; if enough laminae detach, the coffin bone rotates within the hoof or moves downward. The pain is usually so excruciating that often the only humane step is euthanasia.

In 1998 and '99, the U.S. Department of Agriculture checked thousands of horses and found that 2.1 percent had experienced laminitis in the previous 12 months, and that 4.7 percent of those horses had died or been euthanized. Applied to today's estimated population of 9.2 million horses, that would mean 193,000 cases and 9,000 deaths.

For owners, the disease is emotionally and financially draining, and for the horse it is "horrible," said Fran Jurga, editor of Hoofcare and Lameness magazine. Horses are "prey" animals, meaning the hunted, not the hunters. Running is a defense; it's in their genes. If laminitis restricts them, they become depressed. "They know they can't escape," Jurga said. "They're kept in their stalls. They lose their sociability."

Laminitis begins with any of an odd assortment of triggers, many of them involving problems in the gastrointestinal tract, including eating too much green grass or too many carbohydrates. Among other causes are severe colic and pneumonia. But knowing the triggers is not the same as knowing why they cause laminitis. How the feet wind up in trouble is not yet fully understood. All a horse owner can do is try to avoid the triggers and, if laminitis begins, treat the symptoms and reduce the effect of the triggers.

From the first moments after the Preakness, Barbaro faced a serious trigger: uneven weight distribution. A horse with a broken leg will, naturally, shift weight to the other three legs. That burden often leads to laminitis in the hoof opposite the broken leg. But, says Rustin M. Moore, an equine surgeon and researcher at Ohio State University, "we really don't know" the precise sequences and interactions. Sometimes laminitis comes, sometimes it doesn't.

Barbaro's laminitis came soon after major follow-up surgery. Screws in his leg had bent or shifted, and infection had set in. On the leg opposite the broken one, the disease erupted so severely that Richardson had to remove most of the hoof in the hope that Barbaro would grow a better one with working laminae. It was a very long shot.

"We were close to putting him down," Gretchen said. "We just thought we're asking too much of him." She kept turning it over. "You see all this, and it's just like, ‘God, this poor horse.'" But then: "He's back, trying to bite you. Eating. Never stopped eating." Sick horses often retreat to corners, lose their appetites, surrender their spirit. But Barbaro, Roy said, always kept looking at them as if to say "I can get through this." In conversations with Richard-son, they agreed to go forward as long as Barbaro was comfortable.

Slowly, the horse got better. His hoof started to regrow. As the months passed, Richardson took him outside for short walks. Christmas came, and New Bolton released a video of the patient, strolling. Soon, he might be well enough to continue his recovery in more comfortable surroundings, perhaps the fields of Kentucky.

On Monday, January 29, the Jacksons brought grass from the farm to Barbaro, who ate every shoot. Then, as they stood by at his stall, Richardson gave America's most famous horse a tranquilizer and then an overdose of barbiturate, and Barbaro died in a deep sleep. Gretchen hugged the doctor and thanked him. "And he said, ‘I failed you.'"

The turn of the year had brought a swift descent. In the leg with laminitis, the hoof wall was regrowing only in front. The foot was unstable, so Barbaro was shifting more weight to the broken leg, which developed an abscess. Richardson tried to ease the burden on that leg with an exterior scaffold, but then the two front legs developed laminitis. Every leg was impaired. On the last weekend of January, Gretchen and Roy were ready to let go. "I think Roy and I were pushing Dean more than Dean was pushing us," she said.

In the end, was it all for nothing?

"I feel good he had eight months," Richardson said by phone a week later. That was nearly 20 percent of his life, and most of those days were pleasant. "I would love for the public at large to understand that he had lots of time where he was a good, comfortable horse." But the patient died, so "in my mind, I absolutely failed."

Medicine does not advance in a straight line. There are always setbacks, and they increase knowledge and awareness. Maybe, instead of putting down a horse with a broken leg, owners might remember how much was done for Barbaro and "wonder if there's anything we can do for our horse," said Bramlage, the surgeon from Rood & Riddle hospital. Perhaps other veterinarians will see how effective locking compression plates are.

Barbaro's greatest impact will surely be the spotlight he has cast on laminitis. The key is to learn how to prevent it, and researchers believe major progress toward solving its mysteries could be made with $10 million or more, Moore said. Joan C. Hendricks, dean of Penn's School of Veterinary Medicine, said she is angry that so many horse owners still lose their animals to laminitis. "I want it over," she added.

Reaching that goal became easier in mid-February, when Penn received a $3 million gift from the Jacksons, who are both Penn graduates, to endow a chair for the study of equine disease. That position will be "the cornerstone" of a campaign against laminitis, a school spokesman said. The endowed chair will bear the name Dean Richardson.

The Jacksons were still contemplating what sort of memorial to erect to Barbaro, who was cremated. We will never know for certain whether he would have gone on to be one of the truly exceptional racehorses. But the Jacksons still have the memory of a great day in May. "It's just amazing that something we bred won it," Gretchen said. They still have the trophy, and they still have the oil painting that was beside it, done by famed horse painter Fred Stone. It shows Barbaro, with Edgar Prado aboard, flying down the track at Churchill Downs.

Steve Twomey, who has reported for several newspapers over three decades, now teaches journalism at New York University.