Gap in the back of the ankle
You may notice a gap or depression in the tendon about 2 inches above your heel bone. Tendons are long, tough cords of tissue that connect your muscles to bone. When these are dislocated from their proper place, they leave a gap.
Conditions
Achilles Tendon Injuries – Rupture/Tear
This happens when the tendon that connects your heel bone to your calf muscle tears making its fibers separate.