Horse Performance “Not Significantly Affected by Tendon Injury”

A research project funded by The Horse Trust has discovered that a racehorse’s performance does not markedly change after it has recovered from a tendon injury.

The research was led by Bryan O’Meara, who is in the final year of a three year clinical training scholarship funded by The Horse Trust. O’Meara carried out the research at Donnington Grove Veterinary Surgery in Newbury, under the supervision of epidemiologist Dr Tim Parkin from University of Glasgow.

Tendonitis is one of the most common musculoskeletal injuries in racehorses, with a prevalence of 11-30%, according to earlier research.

O’Meara examined the clinical records and racing histories of 400 racehorses who had been treated for superficial digital flexor (SDF) tendonitis injuries over a five year period (2003-2008).

The race records of horses affected by tendon injury were compared with 400 matched control horses that had never suffered SDF tendon injuries. The controls were horses training in the same establishment at the time of injury and of the same age and sex as the case horse.

The Horse Trust-funded research looked at the performance of the racehorses in races before and after treatment for the injury, and at the performance of the control horses before and after the treatment date. The Racing Post Rating (RPR), which is published by the Racing Post after every race, was used as a measure of performance.

O’Meara found that there was no significant difference in RPR before and after the treatment date in case and control horses.

This result is unexpected as in vitro studies have found that healed tendon tissue has reduced elasticity due to the presence of scar tissue. This suggests that a horse with a healed SDF tendon would need to work its muscles harder to compensate and would therefore be expected to have lower performance.

O’Meara said more research is needed to back-up his finding that performance isn’t significantly affected by tendon injury.

“It could be that using Racing Post Rating to measure performance isn’t sensitive enough to pick up a change in the horse’s performance,” said O’Meara. “However, it’s encouraging that there’s no marked change in performance after a horse has recovered from a tendon injury. These findings show that there’s no need to give up on a horse that has a tendon injury – they can still come back and perform well, or can be used for other, less demanding riding activities.”