joint injection

Many equine practitioners have serious concerns about inducing the painful hoof disease laminitis when administering corticosteroids intra-articularly (IA, into the joint). But those fears might be unfounded when treating healthy horses, said Paula Tokawa, DVM, of the University of San Paulo’s School of Veterinary Medicine and Animal Science, in Brazil. Tokawa presented his team’s data on the subject at the 2022 American Association of Equine Practitioners Convention, held Nov. 18-22 in San Antonio, Texas.  

To better define the relationship between IA corticosteroids and laminitis, Tokawa and colleagues conducted a systematic review of the available literature. They identified four studies that matched their inclusion criteria, and only two included control groups.

They found that the overall incidence of laminitis was low, similar to that seen in control groups in the controlled studies.

“Because the overall incidence of laminitis is low and similar to the control groups, it is possible that corticosteroids weren’t necessarily the cause of the laminitis,” said Tokawa. “Other risk factors may explain the development of laminitis.”

For example, overweight horses might be at-risk for equine metabolic syndrome and/or pituitary pars intermedia dysfunction (PPID, formerly known as equine Cushing’s disease) and, therefore, laminitis.  

Regarding dose, one study involved administration of up to 80 milligrams of the corticosteroid triamcinolone (generally, no more than 18 mg of triamcinolone should be administered per horse at any given time). In that study, the incidence of laminitis was not higher than in other studies that used lower doses of corticosteroids.

“In conclusion, corticosteroid injections intra-articularly had only a weak association with laminitis development if the horses didn’t have a history of previous laminitis or other concurrent risk factors,” said Tokawa.  

She emphasized, however, that the current evidence is scarce and intra-articular steroids are not without risk factors.

“There is no safe dose reported in literature that would avoid laminitis development completely. More high-level studies are needed,” Tokawa said.