Without seeing your foot I can not be certain. Possibilities include a Haglund's deformity, a posterior calcaneal spur, a retrocalcaneal bursitis, even a tendon callus.
You should see a podiatrist for more evaluation and treatment options.
Posted By Vivian Abrams DPM on February 18, 2005 at 21:18:42:
In Reply to: What is it???
posted by Kimberly on February 18, 2005 at 15:14:05:
This slip-on device is a soft and stretchable Nylon/Lycra® fabric molded with a proprietary gel pad to protect the entire Achilles tendon of the foot by absorbing pressure and friction resulted from rubbing with the surface of the shoe.