Pain in the rearfoot of children isn't common, however when it does occur, the most common cause is a disorder called Severs disease. It's not a real “disease”, but it's the term that has regrettably stuck. It is actually correctly called calcaneal apophysitis. It is a problem in the growing area at the back of the heel bone. Because it is a problem, of the growing bone, the disorder is self-limiting and will no longer be an issue once the growth of that bone has finished. It is more common around the age groups of 10-12 years.
The classic signs of Severs disease are pain on activity and soreness on squeezing the sides of the rear area of the heel. Initially the discomfort is relatively minor and does not affect activity much, however later it will become more painful and impacts exercise participation and may also lead to limping. The precise cause of it is not known, but it is certainly an overuse type condition because it is more common in those who participate in more sport and more frequent in kids who have a higher BMI. Kids with tighter leg muscles can also be at a higher possibility for the development of this problem.
Commonly, treating Severs disease is load management. The child is encouraged to keep active, but just cut back exercise levels to a level that can be tolerated and not too painful. A soft heel pad in the shoe might be helpful to cushion it. Ice soon after activity may also be useful to help the symptoms. If the calves are tight, then a stretching program ought to be started. At times foot orthotics can be helpful if the arch of the foot is flat. On rare occasions a brace can be used, and all activities halted until it gets better. By the mid-teens the growing area that this occurs at merges with the rest of the heel bone, and this ceases to be an issue at those ages.