A longitudinal study of fractures in 1488 Thoroughbred racehorses receiving intrasynovial medication: 2006-2011.
Authors: Smith L C R, Wylie C E, Palmer L, Ramzan P H L
Journal: Equine veterinary journal
Summary
# Editorial Summary Smith *et al*'s longitudinal analysis of 1488 Thoroughbreds receiving intrasynovial medication between 2006–2011 addressed a clinically important but under-investigated question: does joint medication increase fracture risk in racehorses? Over 3925 treatment sessions affecting 8692 synovial spaces, 96 fractures occurred within 56 days of medication, with 44 cases (3.0% of the population) classified as serious injuries and 11 requiring euthanasia; notably, 56.4% of affected horses returned to racing. The research identified a significant dose–response relationship: horses receiving three or more intrasynovial medication sessions showed a 2.31-fold increased hazard of fracture within 56 days compared with those receiving fewer treatments, independent of age-related risk. A striking finding was that pre-medication diagnostic imaging was performed in only 7.3% of horses that subsequently sustained fracture, suggesting that improved diagnostic protocols prior to treatment could reduce injury rates. For practitioners, this study supports the principle of selective medication use and emphasises the clinical value of thorough imaging assessment before administering intrasynovial agents, particularly in horses with recurrent joint pathology requiring multiple treatment sessions.
Read the full abstract on PubMed
Practical Takeaways
- •Consider cumulative fracture risk when horses require repeated intrasynovial medications—horses with ≥3 previous sessions show significantly elevated injury risk within 56 days post-treatment
- •Implement targeted diagnostic imaging before intrasynovial medication to identify pre-existing damage and reduce post-medication injury rates
- •Counsel owners that 3% serious injury rate exists following intrasynovial medication, but 56% of injured horses may return to racing
Key Findings
- •3.0% (44/1488) of horses suffered serious fractures within 56 days of intrasynovial medication
- •Horses receiving ≥3 previous intrasynovial medication sessions had 2.31 times increased hazard of fracture compared to those with ≤3 sessions
- •56.4% of horses with post-medication fractures returned to racing, while 0.7% were euthanased
- •Pre-medication diagnostic imaging was performed in only 7.3% of horses that subsequently sustained fracture