This condition is a break in the heel bone, called the calcaneus, which forms the back of the foot. This bone supports the foot and is important for normal walking.

This condition is a bony enlargement on the back of the heel that can aggravate the retrocalcaneal bursa, a fluid-filled sac located on the back of the heel between the Achilles tendon and the calcaneus. The bursa can become inflamed and swollen, a condition called bursitis. Haglund's deformity most commonly affects young women.

This isn't a true disease, it's a painful heel condition that affects growing children. It's an inflammation of the growth plate in the heel bone (called the "calcaneus"). Growth plates are places where new bone forms as bones grow and lengthen.