Epidemiology of Musculoskeletal Injury during Racing on New Zealand Racetracks 2005–2011

SIMPLE SUMMARY: There is currently limited information on the types, or risk, of injuries occurring for horses racing in flat races in New Zealand. Race reports and records from six racing seasons were used to determine the reasons why horses failed to finish a race. In total, 544 horses failed to complete a race, of which 177 were due to veterinary events. Most of the veterinary events that occurred during a race were classed as musculoskeletal injuries (136/177; 77%). The rate of musculoskeletal injuries during a race, 0.72 per 1000 starts, was lower than the rates reported for other racing jurisdictions. The condition of the track and the distance of the race were associated with the rate of musculoskeletal injury during a race. There may be differences in the training programmes and racing schedules for horses in the southern hemisphere, which may have contributed to the low rates reported in this study. ABSTRACT: The objective of the study was to determine the incidence of veterinary events that resulted in a horse failing to finish a race and identify risk factors for musculoskeletal injury (MSI) during a race. Data were obtained on Thoroughbred flat race starts in New Zealand between 1 August 2005 and 31 July 2011 (six racing seasons). Stipendiary Steward’s reports were key-word searched to identify veterinary events that prevented a horse from finishing a race. Race data were used calculate the incidence of veterinary events per 1000 horse starts and Poisson regression was used to investigate risk factors for MSI. There were 188,616 race starts and 177 reported veterinary events. The incidence of MSI on race day was 0.72 per 1000 starts, whilst the incidence of respiratory events was 0.21 per 1000 starts. The rate of MSI was significantly lower on ‘dead’ and ‘slow’ tracks compared with ‘good’ tracks and significantly greater in longer races (≥1671 m) compared with races of ≤1200 m. The rate of MSI during flat races in New Zealand appears lower than that reported worldwide, which may be due to the management and training of horses in New Zealand or differences in case definitions used in comparable studies.