Infection is treated by draining and flushing the area and putting the horse on appropriate antibiotics. Horses which are quite lame need to be rested during the recovery period, which can range from three or four weeks, to three or four months. For developmental abnormalities that cause tendon enlargement in foals, a veterinarian usually will put the affected leg in a half-cast for a couple of weeks. When the cast is removed, the leg is put in support bandages, and the foal is kept in a stall for a couple of months. The results usually are good.
Prognosis depends on what's wrong.
With removal of the bone chips, some horses can perform very successfully. Spend a Buck won the Kentucky Derby after surgery to remove a bone chip. With direct trauma, successful recovery depends on which structures are damaged. Prognosis ranges from limited to full recovery. The prognosis for popped knees due to infection depends on the invading organisms, how long they've been there, and the cause of injury.