Etiology of diabetic foot
Reported by different institutes of the diabetic foot ulcer prevalence vary considerably in different countries and different diagnostic criteria may lead to differences in the prevalence rate. In general, patients with diabetes, about 5-10% of patients will have varying degrees of diabetic foot ulcers, which may be 1 percent of patients in need of treatment of lower extremity amputations. In many countries, diabetes is leading to lower limb amputation the most important reasons, such as in the United States each year 60,000 cases of non-traumatic amputations, there is more than half caused by diabetes in diabetic patients, the occurrence of lower limb amputation the risk of non-diabetes 15 times.
In the United States, diabetic foot caused by medical expenses was about 500 million U.S. dollars, of which nearly 1 / 3 for the treatment of diabetic foot ulcers; in the United Kingdom for the treatment of diabetic foot cost is around 12 million pounds (20 million U.S. dollars ). And amputation is the more expensive treatment, amputation in the United States the average medical cost of 25,000 U.S. dollars, compared with 43,000 in Sweden, U.S..
Diabetic foot ulcer pathogenesis
The past used to think that, as a result of diabetic foot complications in the lateral lower limb neuropathy, vascular disease and infection caused by common diseases. However, the view that abnormal plantar pressures, as well as the formation of the corpus callosum leading to diabetic foot disease is the most important factors. In addition, the foot makes the abnormal microcirculation of oxygen and nutrient supply of the obstacles, which is caused by factors of diabetic foot disease; the formation of foot infections are emerging as a result of the first caused by ulcers, rather than a foot infection the appearance of ulcers and infection from shallow to deep-seated development organizations. Diabetic foot complications in the process, the following factors have played a role:
• diabetic neuropathy. Diabetic sensory neuropathy, motor neuropathy and autonomic neuropathy may lead to the occurrence of diabetic foot ulcers. Sensory neuropathy may be caused by the feet of patients with pain, feeling hot and cold and vibration down and lack of feeling of pain can be a direct result of foot injury. And motor neuron disease can cause small foot muscles (foot muscle) and the inability to shrink, making the foot flexor and extensor of the loss of balance, so that buckling claw toes were shaped, convex metatarsal head, flat foot. This change makes the whole body weight on the metatarsal head and foot root, excessive load will result in the pressure foot pressure point of the formation of the corpus callosum, which is a prelude to cause foot ulcers. Autonomic neuropathy can be sympathetic nerve fibers of lower extremity injury, resulting in lower limb skin sweat gland to reduce secretion of sweat, the skin becomes dry and prone to cracks, which provide opportunities for bacterial infection. In addition, the sympathetic skin lesions also lead to lower extremity arteriovenous anastomosis open branch, which will reduce the oxygen and nutrient supply.
• vascular disease and ischemia. Many studies have shown that peripheral vascular disease of lower extremity diabetic foot complications in the role, where this article will no longer be explained in detail one by one.
• abnormal foot pressures and the formation of the corpus callosum.
• other risk factors. In the existence of diabetic retinopathy or neuropathy in diabetic patients, the occurrence of the risk of lower extremity ulcers significantly increased, indicating that these patients there is a wide range of microcirculation 6. Other studies also showed that understanding of diabetes and its management in patients with less risk of foot ulcers was also higher. In addition, age is a risk factor, research shows that 1 / 3 the age of the patients with more than 65 years of age can not conduct its own inspection of the feet.
A variety of bacteria can cause the occurrence of diabetes in patients with infected foot ulcers. Superficial infections by Staphylococcus aureus or Streptococcus caused by, and osteomyelitis, as well as deep abscess, there may be caused by aerobic bacteria (Gram positive cocci), Gram negative bacilli such as Escherichia coli, Klebsiella spp and anaerobic bacteria such as Bacteroides are, Streptococcus caused by joint infection. Aerobic and anaerobic bacteria synergies and a lot of oxygen consumption, resulting in serious infections of the gangrene, and sometimes can produce gas, the formation of gas gangrene. Is sometimes difficult to determine the lesion from the foot of the bacteria isolated a number of pathogens or symbiotic bacteria, which include Staphylococcus and Corynebacterium white, but in any case, these bacteria can lead to infection.
