I hear a lot about footwear and foot care for diabetes. Why is this so important?
Proper care and protection of the feet are extremely important for people with diabetes. This is due to the fact that the feet are frequently affected by diabetic nerve damage with a resultant loss of protective sensation. Protective sensation is the perception of potential injury, such as awareness of sharp, rough, or excessively hot or cold objects or friction, such as rubbing against the inside of shoes. When this is impaired, it is possible for the person with diabetes to sustain wounds, abrasions, burns, or freezing of which he or she may be unaware. Other types of injuries such as bites and blisters can similarly occur unnoticed.
Even fractures to the bones of the foot can occur painlessly when more severe forms of diabetic nerve damage are present. The most serious consequence of unperceived injury is infection. Because the blood supply to the feet may also be impaired, the healing and immune response to both the injury and the infection can be compromised, so that a chronically infected wound results. The most dangerous consequences of chronically infected wounds are spread of infection to the deeper tissues, including the bones, and entry of infectious organisms into the bloodstream, which can lead to blood poisoning (septicemia) or spread by the bloodstream of infection to other body tissues.
Both of these consequences can cause severe illness or even death. Local infection of the bones of the feet can require amputation, since infection in the bone (called “osteomyelitis”) is very difficult to treat. Even powerful modern antibiotics given intravenously over several weeks may fail to completely eradicate infection in bone when its blood supply is poor.
Diabetic nerve damage in the feet may lead to disturbance of the mechanics of the foot, such that pressure may occur on bony areas not designed to bear this. This can cause unusual prominences of the bones of the feet on all of their surfaces, which are more prone to injury than usual. Corns, calluses, cracks, fissures, and ulcers of the feet can all occur in people with diabetes in the absence of specific injury, but as a result of abnormal pressure distribution caused by nerve damage.
For all of these reasons, it is very important to protect the feet by wearing suitable footwear, not going bare-foot, paying attention to the environment (i.e., removal or covering of protruding furniture legs etc. and hard, abrasive floor surfaces), performing daily inspection of the feet, foot hygiene, nail care, and prompt cleaning and dressing of minor injuries.