Inflammation with the bursa powering the heel is named Retrocalcaneal Bursitis. Repetitive tension or friction above the back again on the heel triggers the bursa to swell resulting in heel pain and tenderness, swelling and ankle stiffness. Usually affiliated with Achilles Tendonitis and Haglunds Deformity.   It refers to any soreness https://www.theorthopaedicandpainpractice.com/the-definitive-guide-to-diagnosing-and-treating-ankle-pain-in-singapore/