Inflammation with the bursa powering the heel is known as Retrocalcaneal Bursitis. Repetitive pressure or friction around the again of your heel causes the bursa to swell resulting in heel pain and tenderness, swelling and ankle stiffness. Usually linked to Achilles Tendonitis and Haglunds Deformity.   It refers to any irritation https://www.theorthopaedicandpainpractice.com/the-definitive-guide-to-diagnosing-and-treating-ankle-pain-in-singapore/