During a race, a horse's legs have to support more than 1,000 pounds of bodyweight traveling at speeds up to 40 miles an hour, so it is no surprise that joint injuries are common among racehorses.

Humans and horses are alike in that joint cartilage is highly susceptible to injuries. Joint cartilage suffering from excessive wear and tear likely causes arthritis, which is a common symptom after excessive exercise.

Horses suspected of suffering from arthritis are sent to the Veterinary Department and diagnosed by clinical examination and X-ray check. Veterinary surgeons will provide appropriate treatment to horses according to the progress of their condition, usually reducing the amount of exercise and prescribing joint medication.

In addition to arthritis, the edges of joint bones are at risk of chipping when horses race, especially the front of knee joints and the front of fetlock joints. When chipping problems occur in knee or fetlock, the chips have to be taken out by arthroscopy surgery. The injured horses rest for a period and joint medication must be applied.

Even when horses recover after arthroscopy surgery, there is no guarantee they will completely convalesce and be able to race as well as they previously did. There are different cases with different factors. The later performances of some horses may not be affected at all.

Racing fans have to make their own decisions by observing how the horse works after resuming from a long break. In particular, they need to make an objective assessment of it after they have watched its first few races back. Decisions need to be based on hard facts, and it may need to be down-rated - even if it has been your favorite horse!