Calcaneal apophysitis is a painful inflammation of the calcaneal apophysis believed to be caused by repetitive microtrauma from the pull of the Achilles tendon on the unossified apophysis. It frequently occurs before or during the peak growth spurt and often shortly after a child begins a new sport or season. Coaches and parents should be aware of the clinical symptoms of Sever disease so that early protective and proactive measures and appropriate treatment can be instituted.