Epidemiology of the Neuropathic Foot
In the United States, 1.3 million new cases of diabetes are diagnosed annually in people aged 20 and over.1 The prevalence of diabetes in the United States for all ages is 6.3%. In the Medicare population (aged 65 and over), persons with diabetes incur 1.7 times the health-care expenditures of those without diabetes. Individuals with diabetes who are enrolled in private health insurance through their employers incur higher mean annual costs; $132 billion was spent in 2002, with direct medical expenditures of $91.8 billion and indirect costs of $23.2 billion. Inpatient days accounted for 43.9% of direct medical expenditures. Patients in this group incurred costs that were approximately 2.4 times higher than a similar group without diabetes ($7,778 versus $3,367).2
Neuropathic foot ulcers are a serious complication of diabetes.3 Of the over 20 million patients in the United States with this disease, 15% will develop foot ulcers, and 6% will be hospitalized with this condition.4,5 Vascular disease is 20 times more prevalent in this group, and impaired blood flow impedes healing.6 Functional microangiopathy leads to many sequelae, including neuropathy; this condition is the most important factor leading to ulceration and is present in more than 80% of patients with diabetes and ulcerative lesions.7 Williams et al proved that neuropathy and microvascular complications increased the annual cost of care by 70%. Among the millions of patients in the United States with diabetes, there are an estimated 1200 amputations performed each week; 84% of these surgeries are preceded by a foot ulcer.8,9 The direct costs of lower-extremity amputations in patients with diabetes range between $20,000 and $60,00010; however, when expenditures relating to rehabilitation and failed vascular procedures are coupled with the indirect cost of lost productivity, these amounts exceed these cited costs.11
It is estimated that up to 15% of the 20 million persons with diabetes in the United States will develop a neuropathic foot ulcer.
In a retrospective review of 186 amputations performed on 146 patients with diabetes, Van Damme et al determined that an aggressive control of infection and distal revascularization of calf or foot arteries,12 when feasible, could improve the results of foot surgery in this patient group. Additionally, the poor functional recovery after major amputation (only 63% had autonomic gait with limb prosthesis) argued for foot-sparing surgery whenever possible. A retrospective study by Apelqvist et al involving treatment of patients with diabetes who had foot ulcers indicated the potential cost savings of preventative and multidisciplinary foot care.13
Limb amputation in patients with diabetes is associated with a 5-year mortality rate of 39% to 68%, increasing with more proximal amputation.
Persons with diabetes often develop a triad of neuropathy, including the sensory, autonomic, and motor systems. Insensate feet coupled with dry, ...