A foot ulcer is an open sore on the foot. A foot ulcer can be a shallow red crater that involves only the surface skin or can also be very deep. It may be a crater that extends through the full thickness of the skin, and may involve tendons, bones and other deep structures. People with diabetes and people with poor circulation are more likely to develop foot ulcers. Among people with diabetes, a foot ulcer is the beginning stage of approximately 85% of severe foot infections that ultimately require some part of the toe, foot or lower leg to be amputated. If an infection occurs in an ulcer and is not treated right away, it can also develop into an abscess (a pocket of pus), a spreading infection of the skin and underlying fat (cellulitis), a bone infection (osteomyelitis) or gangrene. This book gathers and presents the latest research in this field.