Haglund’s deformity is usually caused by bursitis or pressure against the shoe. It can be aggravated by the height or stitching of a heel counter of a particular shoe. To some extent, heredity plays a role in Haglund’s deformity. People can inherit a type of foot structure that makes them prone to developing this condition. The calcaneus is shaped differently in different people. People who have a bump underneath the attachment of the Achilles tendon are more likely to develop Haglund’s deformity. This prominent bump squeezes the soft tissues between the bone and the back of the shoe. Over time, this irritates the soft tissues and causes inflammation. This can cause swelling and thickening of the tissues, which makes the pressure even worse.

Haglund’s deformity can occur in one or both feet. The primary symptom of this deformity is pain at the back of the heel. The bursa on the back of the heel can become swollen and inflamed as well, causing bursitis .The bumps do not usually cause any problems with function, such as walking, except for the pain that occurs when the area is inflamed.