Biomarkers for monitoring racehorse musculoskeletal injuries and injury risk

In most catastrophic racehorse fractures, postmortem examinations have found evidence of chronic accumulation of microdamage attributed to high-stress loading during high-speed exercise. Biological responses to this microdamage accumulation may be an avenue to identify biomarkers indicative of this damage, offering insight into musculoskeletal adaptation and dysregulation. Since the first description of an equine bone degradation biomarker in 1975, our understanding of various biological molecules associated with bone modeling, remodeling, and damage has greatly improved, although none has become a mainstream, clinical screening tool. Here, we describe the history and current state of research on biomarkers in racehorse musculoskeletal health. Although not yet in clinical use, biomarkers present a promising area of research for screening and monitoring racehorses at risk for musculoskeletal injury.