Joint Injections: “Litmus Test” for HISA

Last month, California Horse Racing Board (CHRB) chairman Greg Ferraro scratched a persistent industry itch.

While discussing his thoughts on the rollout of the Horseracing Integrity and Safety Act’s (HISA) drug control program, Ferraro shared his fears that the new federal rules on joint injections were weaker than had previously existed in California.

“It’s a step backwards,” Ferraro said. And this regulatory reshuffle, he added, could lead to an increase in California of irreparable musculoskeletal injuries, especially of the fetlock joint.

“California is the point of the spear in terms of dealing with the public and the liability of horse racing,” said Ferraro, advocating for federal adoption of California’s joint injection regulations. “I think they should use us as a sort of leader in animal welfare and jockey welfare.”

Ferraro’s comments re-ignited a debate that has been simmering away in some fashion or other for decades. Just take the New York Task Force report into the rash of fatalities that bedeviled Aqueduct during the winter of 2011-2012.

“The Task Force believes that the use of systemic or intra-articular corticosteroids may have impaired veterinarians and trainers in accurately assessing horses’ soundness leading up to a race,” the report found.

“The Task Force also believes that the use of these medications too close to the race may have limited the ability of the NYRA veterinarians to identify the presence of pre-existing conditions disposed to progressing to catastrophic injury.”

The New York Task Force’s findings frame a key bone of contention among trainers, veterinarians and regulators: What is a smart regulatory timeframe for limiting joint injections before workouts and race days?

HISA’s joint injection rules bar joint injections within 14 days prior to post-time, and within seven days of an official workout.

In California prior to HISA, the intra-articular corticosteroid fetlock injection rule mandated a 30-day stand down period prior to racing, and all corticosteroid joint injections had a 10-day stand down before workouts.

After those rules were adopted, the number of irreparable fetlock injuries in California had fallen off precipitously. Experts point to this as a prime example of the long-term systemic effects from corticosteroid usage.

Even so, there remains some skepticism within the industry that California had indeed got it right.

“Thirty days is ridiculous,” said trainer Mark Casse, who argues that such a rule is difficult to police. “What happens is, when you make rules that you cannot really enforce, it only makes the bad guys better because they don’t care.”

Another key point in this whole debate? Not all joint injections are made equal.

In the decade since the New York report was issued, veterinary experts describe a shift away from corticosteroids towards hyaluronic acid joint injections, and biologic therapies like IRAP and platelet-rich plasma (PRP) injections.

They don’t mask injuries the way corticosteroids can and are better at promoting joint health and healing in a way more advantageous to the horse in the long term, say proponents of these therapies.

Nevertheless, these same proponents voice frustration that the rules governing joint injections often treat corticosteroids and biologic therapies as equals.

“A lot of these injections are actually helpful, especially when you’re doing PRP or you’re putting [hyaluronic] acid in there,” said Casse, about biologic therapies. “I can tell you for a filly like Tepin, we would put acid in her ankles. We probably did it 20 times and she ran for years.”

Internationally renowned orthopedic surgeon Larry Bramlage is among those experts who believe HISA has got its rules surrounding corticosteroid joint injections about right.

“I think it is a good approach to being able to treat the joint that has been properly examined,” said Bramlage, who explained that corticosteroid joint injections should never be part of a “routine training program,” no matter the stand down time. “You want plenty of time to reassess the condition of the joint without the corticosteroid masking anything.”

Part of Bramlage’s reasoning is how the marketplace for corticosteroids has evolved from high-dose, long-lasting versions like Methylprednisolone acetate–also called Depo-Medrol–to lower-dose, shorter acting corticosteroids like Betamethasone and Vetalog.

What kind of difference are we talking about? “We tend to think in terms of volume injected into a joint,” said Bramlage. Depo-Medrol can come in doses as strong as 40 milligrams per milliliter (mg/ml). Betamethasone, on the other hand, typically comes at a strength of 6 mg/ml.

“The original one–and as it turns out the most harmful one–was Depo-Medrol. When I was a student, we would put as much as two cc’s [cubic centimeters] of Depo-Medrol when we were treating a joint,” explained Bramlage.

“But it’s very long acting,” he added. “Its crystals are absorbed very slowly, so it can be found up to three months in the joint after you put it in. And that is a big disadvantage.”

Bramlage believes that the new wave of corticosteroids continues to play a role in managing the sorts of routine aches and pains that accompany high stress training programs.

“If you let inflammation go unchecked within a joint, it can eat up the articular cartilage. So just leaving a joint seriously inflamed without treating it with anything is also not the best route once you know there is no structural damage,” he said.

And the use of a low-dose, short acting corticosteroid like Betamethasone within a week of a timed workout, Bramlage said, is “a medically sound” approach if the joint has been properly assessed beforehand.

If the corticosteroid is eliminated from the horse’s system enough to be undetectable in a test, he added, and the horse is still exhibiting signs of lameness, then there is a strong possibility the lameness is tied to some deeper-seated structural problem. A burgeoning stress fracture, for example, or abnormal bone remodeling. “That is the rationale for the stand down time,” he said.

The modern short-acting corticosteroids “reduce the inflammation and then get out of the way so you can read the joint again,” explained Bramlage. “And if there is a physical injury, a structural problem of some kind, it’ll show up again.”

Other veterinary experts in the field have a slightly different take.

Though a corticosteroid won’t necessarily show up through testing after seven days, it can still impart a systemic effect on the horse through effects like decreased inflammation in the joint and reduced lameness, said veterinarian Wayne McIlwraith, a distinguished professor at Colorado State University and like Bramlage, internationally renowned in the field.

As an example, McIlwraith cited a study he was involved in from 1997 where researchers studied the effects from triamcinolone acetonide joint injections–drugs which come under the trade names Vetalog or Kenalog. The horses were suffering osteoarthritis in the knee and were injected at 14 days and 28 days after the study start.

“We showed that lameness was significantly reduced at day 70–42 days after the second injection,” said McIlwraith. He described these effects as reduced inflammation in the joint fluid and in the joint lining membrane, as well as beneficial effects on the articular cartilage.

These effects were seen “whether we injected the osteoarthritis joint or we injected the opposite normal joint,” McIlwraith said. “In other words, a systemic effect that was very long lasting.”

McIlwraith and his fellow researchers used the same study design on Depo-Medrol–then considered the most potent corticosteroid available. They found “significant deleterious effects” to the joint cartilage in both the osteoarthritic joint and the opposite “good” joint, he said.

“The bottom line is that all the tissues of the musculoskeletal system are being exposed to the multiple complex effects of corticosteroids,” he said.

The fetlock has long been the Thoroughbred racehorse’s Achilles heel. As an example, fetlock failures constituted in California nearly 60% of all musculoskeletal injuries that proved fatal during the 2018-2019 fiscal year, according to CHRB data.

The CHRB instituted its 30-day standdown regulations for corticosteroid fetlock injections on Oct. 19, 2021.

In the 20 months preceding that date, there were 83 catastrophic fetlock failures statewide, according to CHRB data. In the 19 months after that date, there were 24 catastrophic fetlock failures statewide.

Zeroing in specifically on Los Alamitos, the number of catastrophic fetlock failures dropped from 21 to just three during those two same periods of time bookending the rule change.