Inflammation on the bursa guiding the heel is referred to as Retrocalcaneal Bursitis. Repetitive force or friction around the back again on the heel will cause the bursa to swell leading to heel pain and tenderness, swelling and ankle stiffness. Often linked to Achilles Tendonitis and Haglunds Deformity.   Can arise https://www.theorthopaedicandpainpractice.com/the-definitive-guide-to-diagnosing-and-treating-ankle-pain-in-singapore/