Heel pain due to retrocalcaneal bursitis-radiographic diagnosis (with an historical footnote on Sever's disease).

Retrocalcaneal bursitis is a distinct condition causing posterior heel pain in active, healthy children. It appears to result from post-traumatic inflammation of the soft tissues of the posterior heel, and is unrelated to avascular necrosis of the calcaneal apophysis. The diagnosis may be confirmed radiographically by the loss of the lucent retrocalcaneal recess, with a normal Achilles tendon and superficial soft tissue contour, and intact cortex of the underlying os calcis.