A pump bump is an enlarged piece of bone situated behind the heel bone and is a bothersome ailment commonly experienced by athletes. It can be quite troublesome to deal with. The prominent portion of the heel bone rubs against footwear, leading to bursitis and blisters. This bursitis may be rather puffy. https://runningone.net/how-to-deal-with-a-bony-bump-at-the-back-of-the-heel/