A new study shows that more than 86,000 people a year end up in the emergency room because they tripped over the family pet. The data from the Centers for Disease Control and Prevention show that while we sometimes trip over our cats, dogs are the primary cause of pet-related falling accidents. Dr. Judy Stevens, whose research focuses on preventing falls in senior citizens, said she’s often heard people explain that they were tripped up by the family pet, but until now there were no data to show how common a problem it really is.