A foot ulcer is an open wound on the leg or foot that may or may not be painful. It can affect only the surface of the skin or may extend deeper to affect other structures like tendons or bones. It typically does not heal on its own and has a high risk of infection.
There are many causes of foot ulcers, such as impaired blood circulation, a compromised immune system, and systemic diseases such as sickle cell anemia. However, the most common cause of foot ulcers is diabetes due to the associated peripheral neuropathy and poor blood flow to the limbs.
Ulcers usually develop at areas of high stress: the ball of the foot and heel, or areas where shoes rub against the skin. Trauma such as stepping on a sharp object or scratching the skin may also lead to the development of a wound. If left untreated, the ulcer can become gangrenous, leading to amputation.