Updates on intra‐articular corticosteroid administration in horses

Summary Intra‐articular (IA) corticosteroid administration in equine athletes has gained increased attention recently, particularly in racing. Despite widespread corticosteroid use in equine practice for decades, there are still a lack of equine‐specific studies to address key questions related to their use. Extrapolation of best practices from human literature supports that while IA corticosteroids elicit transient symptom‐modification of osteoarthritis (OA), they can have deleterious effects on articular cartilage depending on drug selection, dose and time‐ indicating the lowest efficacious dose should be used to achieve clinical benefit. While there are limited data supporting current clinical protocols related to dose or injection frequency diminishing returns have been noted with multiple‐injection protocols. Recent studies have led to heightened awareness of equine endocrinopathies and the sensitivity of equine patients with those disorders to the effects of steroids, putting them at increased risk for complications such as laminitis and secondary infection. These findings prompt reconsideration of long‐term or high‐dose corticosteroid administration, particularly given the evolution of alternative IA orthobiologic and immunomodulatory therapies for OA, which require further investigation and comparison for relative modification of clinical signs and disease progression. As much of the referenced literature does not permit direct comparisons across studies, further research is needed to compare corticosteroids at equivalent body doses and dosing intervals in horses with and without endocrinopathies. Without such studies, definitive evidence linking IA corticosteroid use to laminitis risk, subchondral bone injury or catastrophic injury is lacking at this time. This narrative review seeks to summarise the current literature available as well as gaps in knowledge on equine IA corticosteroid use for the practising clinician.