Epidemiology including risk factors and primary prevention
The exact number of people who have had amputations worldwide is difficult to ascertain, as many countries do not keep records of the number of people with limb amputation. Each year over 150,000 individuals are admitted to hospitals to undergo amputations secondary to peripheral vascular disease or diabetes.4 As of 2005, an estimated 1.6 million people with amputation live in the United States, of whom approximately 65% underwent lower limb amputation.10 Of the approximately 1 million unilateral lower-extremity amputations due to dysvascular conditions, the most common were toe (33.2%), transtibial (28.2%), transfemoral (26.1%), and foot amputations (10.6%). Ankle disarticulation (Syme), through-knee, hip disarticulation, and hemipelvectomy amputations combined added an additional 1.5% of all amputations.1,2 Minority populations have been shown to have different incidences of lower limb amputation for reasons not currently understood.6 Asians were found to have a lower relative risk of lower limb amputation, while African Americans have a higher risk. This seems to be independent of other risk factors associated with minority status, such as a higher prevalence of diabetes and hypertension.9 Men more frequently require amputation than women, especially for vascular disease.
Persons with diabetes are anywhere from 8-24 times more likely to undergo a lower limb amputation than non-diabetics.8 Patients who have diabetes tend to have more minor amputations (e.g., toe, ray, partial foot) than individuals who have peripheral vascular disease, who have more major limb amputations (ankle or proximal).1,7 Nonetheless, the frequency of subsequent amptuation is also higher in diabetics.8. Significant reduction in the incidence of lower extremity amputation has been achieved with the introduction of specialist diabetic foot care clinics,9 and this is reflected by projected limb loss estimates, which suggest a substantial decrease in the prevalence of individuals living with limb loss, with just a 10% reduction in incidence rates secondary to dysvascular disease.10