The injection of cortisone into a localized area of the foot or ankle is used to relieve inflammation and discomfort. This injection can be used in joints, bursa, or at the attachment of tendons or ligaments to the bone. The most common of these is the attachment of the plantar fascia to the heel.
Cortisone is a natural hormone in your body. The injection concentrates the amount available in a specific area, with a minimum effect on the rest of the body. The concentration of the injection in the inflamed area can relieve the pain of the inflammation with a much smaller amount of medication than if given systematically.
After an injection of this type, the area injected will remain numb for five to six hours, then the sensation with gradually return. When the sensation returns, there is usually less pain than before the injection was given.