Caring for the Diabetic FootKenneth G. Venos, M.D.
Improvements have been made in the medical management of diabetes; however the diabetic foot remains vulnerable. In fact, undiscovered diabetics are frequently “found” when a healing ulcer on the foot, patch of gangrene, or minor trauma brings them to the attention of a physician. Of the 12 million diabetic persons in this country, about twenty-five percent will develop a severe foot or leg problem during their lifetime. Amputation statistics indicate that diabetes mellitus is one of the leading causes of limb loss of the lower extremity in the western world.
Diabetics are fifteen times more likely than non-diabetics to develop gangrene of the extremities. About fifty percent of all non-traumatic amputations occur in diabetics, accounting for about 120,000 amputations annually. Twenty to twenty-five percent of hospitalizations for diabetes are due to foot infections which account for more hospital days than any other complication of the disease. The duration of the diabetes and the degree of control are clues to the likelihood of deep foot infection or other problems. Surprisingly, however, the duration and severity of the diabetes is not directly related to the severity of the complications. A vast majority of complications occur in patients with a milder form of diabetes. Once breakdown has begun in one diabetic foot, it is generally not long before problems are seen in the other foot.
Renowned centers such as Rancho Los Amigos (USC), the Joslin Clinic (Harvard University), and Barnes Hospital (University of Washington at St. Louis) have recognized the wide diversity of skills required to successfully manage the diabetic foot, and have implemented multi-disciplinary, multi-specialty teams in their programs.
An aggressive multi-disciplinary approach is the key to avoiding serious problems. Even a seemingly minor problem often needs immediate attention because of the dire consequences of neglect. The well-coordinated team approach is a cost effective method for dealing with the economic problems of the patient with a diabetic foot. Patient costs are controlled through careful planning and implementation of treatment prescriptions prior to infection or hospitalization.
Diabetic patients often have no pain whatsoever accompanying their infections. In such a situation, most patients have both a circulatory and neurologic problem. As a result, careful examination of all surfaces of the feet is mandatory. The diabetic patient must be evaluated by their family physician, internist or endocrinologist for fungal infections, other dermatitis, general diabetic control ultimately systemic illness.
X-rays of the foot are taken and may reveal bony erosions or changes indicative of bone infection or osteomyelitis. Considerable time may elapse before any x-ray changes due to bone infection become apparent. The blood supply of the leg and foot must also be evaluated. A simple test with an ultrasound Doppler device can help the examining physician predict whether or not a lesion will heal or if a vascular or blood vessel surgery is necessary. Feet with deformities such as bunions, claw and hammertoes, or pressure beneath the ball of the foot or metatarsal area should be relieved surgically before a pressure ulcers or infection develops.
Once an ulcer has developed, it must be attended to immediately. A history of fever and chills, nausea or vomiting in the presence of a foot ulcer or area of redness, must be considered a life-threatening limb infection. A broad spectrum antibiotic and appropriate surgical intervention removing all dead tissue is often necessary. In less serious situations, local or dead tissue is removed in the physician’s office. Appropriate cultures for bacteria are taken and frequently, a broad spectrum oral antibiotic is given if there is any evidence of local spread.
A lesion on a weight bearing surface requires complete avoidance of weight bearing in order to heal. Customized shoes, crutches, or a wheelchair may be recommended. Daily inspection of the ulcer is crucial. The patient is usually seen in the physician’s office on a weekly basis. At times, total contact casting over an antibiotic dressing will hasten the recovery of the ulcer. Throughout such episodes, good control of diabetes is especially important to minimize the risk of complications. Frequent capillary glucose monitoring is recommended at least four times a day. Patients usually maintained on oral agents may find that insulin is required during these episodes.
Preventative care and education of patients with newly diagnosed diabetes, including daily foot inspection, cessation of smoking, dietary modification, control of glucose levels, moderate exercise and weight loss are all important. During all routine visits, the foot is carefully examined by the physician. Modifications of footwear include shoes that fit well, and have a deep and wide enough toebox to allow toes and forefeet to survive without pressure and ulceration. Early identification of small lesions and pressure points by daily foot inspection can save a patient from an amputation and/or prolonged hospitalization.
In the diabetic patient who has had a foot infection, the loss of a limb remains a substantial consideration for about six months after the infection. Therefore, because of the enormous human and economic cost of foot ulcers in the diabetic patient, and their complications, the prompt diagnosis and treatment of minor problems is extremely important. With daily foot care and the participation of a multi-disciplinary preventative treatment approach to the management of these problems, there can be a significant improvement in patient outcomes. Experts predict a fifty to seventy-five percent reduction in amputations using this approach to the care of the diabetic foot.
Remember: Careful, regular examination of the diabetic foot is essential so that problems can be identified and treated as early as possible.