Retrocalcaneal bursitis is inflammation of the small fluid-filled sac (bursa) between the back of the heel bone and the Achilles tendon, just above the point where the tendon connects to the bone. The inflammation causes swelling, tenderness, and pain on the back of the foot.
Retrocalcaneal bursitis develops gradually, usually from pressure from the back of a shoe. Activities that repetitively overflex the foot upward, such as hill running, cause the Achilles tendon to press against the bursa and can also cause inflammation. Wearing shoes and being active can often make symptoms worse; however, symptoms usually improve with rest.
Treatment for this condition may include changing footwear if necessary, ice massage, and nonsteroidal anti-inflammatory drug (NSAID) treatment. Runners are advised to avoid hill running, reduce mileage, and run on a soft yet firm surface while rehabilitating.
WebMD Medical Reference from Healthwise