Bone biomarkers and risk of fracture in two- and three-year-old Thoroughbreds.
Authors: Jackson B F, Dyson P K, Lonnell C, Verheyen K L P, Pfeiffer D U, Price J S
Journal: Equine veterinary journal
Summary
# Editorial Summary: Bone Biomarkers and Fracture Risk in Young Thoroughbreds Fracture risk in young racehorses represents a significant welfare and economic concern, prompting investigation into whether measurable bone turnover markers could serve as predictive tools. Jackson and colleagues measured four serum biomarkers—osteocalcin (bone formation), PICP and ICTP (collagen turnover), and CTX-I (bone resorption)—in two- and three-year-old Thoroughbreds before their racing season, then tracked which horses sustained fractures during competition. Despite measuring these established indicators of skeletal metabolism, the researchers found no significant relationship between biomarker levels and subsequent fracture occurrence, suggesting that single pre-season measurements of these markers lack predictive value in young racehorses. Whilst this represents a negative finding, it has important implications for practice: practitioners cannot currently rely on these biomarkers as screening tools for fracture susceptibility in juvenile horses, and fracture risk assessment must continue to depend on clinical evaluation, training history, and radiographic assessment rather than biochemical profiling. Future research measuring biomarkers serially throughout a training season, or evaluating their predictive value in mature horses, may yet establish whether bone turnover markers have clinical utility in other contexts.
Read the full abstract on PubMed
Practical Takeaways
- •Bone biomarker testing cannot currently be used as a screening tool to identify young racehorses (2-3 year-olds) at high risk of fracture before racing
- •Alternative assessment methods beyond these four biomarkers are needed to predict fracture susceptibility in young Thoroughbreds
- •Fracture risk management in young racehorses should rely on clinical evaluation and other established methods rather than these biomarkers
Key Findings
- •Bone biomarkers (osteocalcin, PICP, ICTP, CTX-I) cannot reliably identify 2- and 3-year-old Thoroughbreds at increased fracture risk in subsequent racing season
- •Current panel of bone biomarkers lack predictive value for identifying young horses susceptible to fracture
- •Serial measurement and assessment in older horses may warrant further investigation for biomarker utility