Achilles tendon enthesopathy is pain where the Achilles tendon attaches to the back of the heel.
The cause is chronic stretching of the Achilles tendon where it attaches to the heel. Contracted or shortened calf muscles caused by being sedentary and overweight or caused by athletic overuse increase the risk.
People typically feel pain at the back of the heel below the top of the shoe when walking.
The diagnosis is based on a physical examination of the tendon. Manually bending (flexing) the ankle during the examination usually makes the pain worse.
Exercises that stretch the calf muscles for 10 minutes 3 times daily can help. A person can stretch the calf muscle while facing a wall at arms' length, with the knees straight and the foot bent upward. To minimize stress to the Achilles tendon when walking, the foot and ankle should be moved actively through the ranges of motion for about a minute when rising after long periods of rest. Night splints may also be used to stretch the tendon during sleep and help prevent shortening. Heel lifts should be used temporarily to relieve pain and decrease stress on the tendon while walking.
Resource: Merck Manual Home Edition