The Achilles tendon can be a fibrous tissue that connects the calf muscle to your heel bone. It causes swelling and stiffness from the back from the heel. Plantar Fasciitis is undoubtedly an overuse on the ligament at the bottom with the arch from the foot which causes pain at https://www.theorthopaedicandpainpractice.com/why-does-the-back-of-my-heel-hurt/