Treatment of osteochondrosis dissecans in the stifle and tarsus of juvenile thoroughbred horses.

The research article investigates the effect of arthroscopic surgery on juvenile thoroughbred horses diagnosed with trochlear ridge OCD of the femur (stifle OCD), or intermediate ridge of the tibia (tarsal OCD). The study discovered that horses who underwent this surgery performed less successfully in races compared to non-treated controls, with fewer race starts, wins, places, and smaller amounts of prize money earned.

Methods of the Study

• The study was a retrospective case control study involving thoroughbred weanlings and yearlings that presented stifle (37 cases; 22 male, 15 female) and tarsal (35 cases; 22 male, 13 female) OCD conditions.
• The researchers established outcome measures related to racing performance, including the number of race starts, wins, places, and the amount of prize money earned from races when the horses were 2- and 3-years old, and also from the total period studied.
• The researchers then compared these figures from the treated horses to two age and sex matched controls using multilevel linear regression models.
• The research exploration also extended to examining if the age of the horse at the time of surgery and the experience of the surgeon have any impacts on the outcomes for cases with stifle OCD.

Results of the Study

• The results showed that the stifle OCD cases, where surgeries were performed between 190-563 days of age, had significantly lower total earnings (P = .043), and fewer total starts (P = .001) and 1st place finishes (P = .003) than their matched controls.
• For tarsal OCD cases, surgeries were performed between 127-470 days of age, there were fewer starts by cases than controls (P = .018).
• Younger horse age at the time of surgery and less experienced surgeons were significantly associated with worse outcomes for stifle OCD cases.

Conclusions of the Study

• The results suggested that stifle OCD cases perform less successfully as racehorses than non-treated matched controls.
• The age of the horse at the time of surgery was also found to have an effect on subsequent racing performance.