Racing and sales performance in Thoroughbred yearlings after carpal osteochondral fragment removal.

Background: While radiographically evident carpal osteochondral fragments (COF) in Thoroughbred yearlings impair sales, their impact on future racing performance has been minimally investigated.

Objective: To assess the impact of COF on Thoroughbred yearling sales and racing performance, and whether these are improved by arthroscopic removal. We hypothesised that surgical removal of COF improves Thoroughbred yearling sales and racing performance.

Study design: Retrospective observational.

Methods: Using clinical records from years 2015-2018, 46 Thoroughbred yearlings with COF were identified and allocated to a surgically (SX group, n = 26) or conservatively (No-SX, n = 20) treated group. A control group consisted of 138 sire- and year-matched siblings without radiographic findings. Data were analysed using ANOVA with backward selection regression.

Results: Identification of COF on radiographic surveys was associated with significantly lower sales prices and total winnings, regardless of treatment, with horses in both SX and No-SX groups achieving fewer starts and seasons raced when compared with controls. Overall variables and co-variables indicating racing and sales performances did not differ significantly between the SX group and the No-SX group; however, horses with COF treated surgically were more likely to achieve a racing career than those treated conservatively (OR: 6.2, p = 0.03, 95% CI: 0.987-69.690). When compared with control horses, conservative management of COF was overall associated with significantly poorer sales and racing performances. No such differences were observed between the SX group and the control group.

Main limitations: The limited sample size and single centre limit generalisability. No further radiographic re-examination data were obtained during horses' careers.

Conclusion: Our data indicates that COF can impair a Thoroughbred's racing and especially sales performance. Larger cohorts of affected horses may help demonstrate the benefits of arthroscopic COF removal on sales and athletic performance.