There are two main theories regarding the occurrence of chronic complications of diabetes due to hyperglycemia, namely sorbitol theory and glycosylation theory.
Sorbitol theory
Hyperglycemia will cause a buildup of glucose in the cells and certain tissues and can transport glucose without insulin. This excess glucose will not metabolized normally discharged through glycolysis, but most of aldose reductase enzyme mediated be converted to sorbitol. Sorbitol will accumulate in cells / tissues and cause damage and changes in function.
Glycosylation theory
As a result of hyperglycemia will cause the glycosylation of the proteins, especially lysine-containing compounds. The process of glycosylation on the basal membrane proteins can explain all the complications of both macro and micro-vascular. The main factor that the incidence of diabetic foot is angiopathy, neuropathy, and infection. Neuropathy is an important factor for the occurrence of diabetic foot. The presence of peripheral neuropathy will cause sensory and motor disturbances. Sensory disturbance will lead to lost or reduced sensation of pain in the feet, so it will be traumatized unnoticed resulting in motor disorders foot ulcers will result in leg muscle atrophy, thus changing the fulcrum which causes ulceration of the legs of patients. Angiopathy will cause disruption of blood flow to the feet. If the blood clots occur in the blood vessels bigger then the patient will feel pain in the legs after walking a certain distance. Manifestations of other vascular disorders that can be: toe feels cold, leg pain at night, arterial pulse is lost, the foot becomes pale when raised. The existence of angiopathy will cause a decrease in the intake of nutrients, oxygen (acid) and antibiotics causing poor healing wounds (Levin, 1993). The infection is often a complication that accompanies diabetic foot due to reduced blood flow or neuropathy, so angiopathy and infection factors affect the healing or treatment of diabetic foot.
