Bursitis is a condition that occurs when a bursa becomes inflamed. Bursae are small, fluid-filled sacs found throughout the body that help reduce friction between tissues such as muscles, tendons and bones as they move over one another. There area several bursae located in the feet, common areas include, between the Achilles tendon and the heel bone, in the joints of the toes, between toes and around the ankle. However, additional bursae can develop in response to repeated pressure or “micro-trauma” from walking, footwear or altered foot mechanics. When this ongoing stress continues, the protective bursa can become irritated and inflamed, resulting in bursitis.