Risk factors for cranial cruciate ligament rupture in dogs participating in canine agility

Cranial cruciate ligament rupture (CCLR) is one of the most common causes of pelvic limb lameness in dogs. Risk factors for CCLR include breed (especially large and giant breeds), body weight, gender and spay/neuter status, and age. Few studies have evaluated physical activity and fitness indicators, however, as risk factors for disease. This study used an online questionnaire distributed primarily via social media to assess risk factors for CCLR in dogs actively engaged in agility training or competition to determine demographic and physical activity factors associated with rupture. Data from 260 dogs with CCLR were compared to similar data from 1006 dogs without CCLR. All dogs were actively training or competing in agility at the time of CCLR or the time of data submission, respectively. Physical characteristics associated with increased risk of CCLR included younger age, spayed female sex, greater body weight, and greater weight to height ratio. Agility activities associated with increased odds ratios included competition in events sponsored by the North American Dog Agility Council (NADAC), competing at novice and intermediate levels, and competing in fewer than 10 events/year. Odds ratios were lower in dogs that competed in events sponsored by United Kingdom Agility International (UKI). Other activities associated with increased odds ratio for CCLR included involvement in flyball activities and short walks or runs over hilly or flat terrain on a weekly basis. Activities associated with decreased odds ratio included involvement in dock diving, barn hunt, nosework, or lure coursing/racing activities and participation in core balance and strength exercises at least weekly. These results are consistent with previous studies demonstrating that body weight and spay/neuter status are risk factors for CCLR in dogs. This is the first report to demonstrate that risk of CCLR in agility dogs is decreased in dogs that engage in regular core strengthening exercises, compete more frequently, compete at higher levels, and compete in more athletically challenging venues.