Clinically, diabetic patients are affected by long-term high blood sugar, lower limb vascular sclerosis, blood vessel wall thickening, elasticity decline, blood vessels are prone to the formation of thrombosis, plaque, and lower limb vascular occlusion, branch end nerve damage, resulting in lower limb tissue lesions. The “foot” is the farthest from the heart, and the occlusion phenomenon is the most serious, which leads to edema, blackening, decay, necrosis, and finally has to be amputated.
Statistics report that the amputation of diabetic patients accounts for 40%-60% of all non-traumatic lower limb amputations, about 85% of diabetic patients have foot ulcers before amputation, 50%-70% of diabetic patients have gangrene at the time of amputation, amputation hand trauma surface is large, the wound is difficult to heal, easy to infection and recurrence, the mortality rate is 51% within two years after amputation, the rate of amputation of the opposite limb is greater than 50%. Therefore, traditional treatment is risky and ineffective.
I. Overview of diabetic foot
According to the definition of World Health Organization (WHO), diabetic patients have lower limb infection, ulcer formation and/or deep tissue destruction due to combined neuropathy and various degrees of peripheral vasculopathy. Clinically, due to the long-term impact of hyperglycemia in diabetic patients, lower limb vascular sclerosis, thickening of the vessel wall, and decreased elasticity, blood vessels are prone to thrombosis, and set into plaque, resulting in lower limb vascular occlusion, nerve damage at the branch end, resulting in lower limb tissue lesions. The “foot” is the farthest from the heart, and the occlusion is the most serious, which leads to edema, blackening, decay, necrosis, and gangrene. Among the problems of the diabetic foot, the main serious consequences are foot ulcers and amputations. Currently, amputation, bypass, angioplasty stent implantation or dry thin chest transplantation are generally performed in major hospitals for diabetic foot patients.
It has been demonstrated that amputation rates vary considerably between countries and between geographic regions. Between 40% and 60% of all non-traumatic lower limb amputations are done in patients with diabetes. It has been demonstrated that approximately 85% of diabetic patients have foot ulcers prior to amputation, 50-70% of diabetic patients have gangrene at the time of amputation, and 20%-50% have co-infection.
In the majority of patients, amputation is necessary because of a combination of deep infection and ischemia. According to a study of 15,089 diabetic foot cases by the world’s only diabetic foot research institute, the Jia Chunbao Diabetic Foot Research Institute, most of the patients with “diabetic foot” are old, and the traumatic surface of the surgical hand is large and the wound is difficult to heal, so it is easy to get infected and recur. Moreover, after amputation, the mortality rate is 51% within two years, and the amputation rate of the opposite limb is more than 50%, so the risk of traditional treatment is high.
Second, the stages and clinical symptoms of diabetic foot
Stage I Asymptomatic stage, discomfort only after intense exercise
Stage II Lower limb pain when walking at normal speed
Stage III Lower limb pain at rest – resting pain
Phase IV Lower limb pain at rest, accompanied by local nutritional disorders, dystrophic ulcers, gangrene
III. Pathogenesis of diabetic foot
1, due to the diabetic patients in a long-term state of hyperglycemia, blood viscosity increases, too much blood sugar will lead to hardening, brittle, thickening of blood vessels, vascular deformation Wan ability to reduce the blood supply; on the other hand, increased blood viscosity also leads to vascular inflammation, many of the above reasons, will lead to the formation of blood vessels thrombosis, resulting in occlusion of blood vessels, resulting in a serious lack of blood supply, organ malnutrition, metabolism If the body tissues and organs are in this state for a long time, it will easily lead to necrosis of the organ division, as the “foot” is the farthest from the heart, the occlusion of blood vessels is the most serious phenomenon, which can easily lead to edema, blackening, decay, necrosis, the formation of foot necrosis.
2, on the other hand: vascular injury and occlusion, but also lead to injury tissue nerve damage, causing the limb vascular phytonuropathy to weaken vasomotor, local tissue resistance is reduced, a small trauma can cause infection, and because of local sensory impairment, small lesions can not be treated in a timely manner, resulting in rapid expansion of the wound. Also due to limb sensory impairment, it can easily lead to burns. Neuropathy can cause atrophy of the small muscles of the foot, and due to the absence of antagonistic pulling of the long muscles, claw-like toes are formed [especially the third, fourth and fifth toes.
This deformity makes the metatarsal head a weight-bearing support point for the sole of the foot, and due to friction, there is callus formation, which is highly susceptible to infection and penetrating ulcers, and in severe cases, spreads to the nearby bones causing osteitis. Due to the loss of deep sensation and impaired joint movement reflex, the patient unconsciously overloads some joints and loses the protective effect against repeated trauma, making the joints and joint surfaces very irregular and prone to fractures, joint dislocation and subluxation, especially in the metatarsophalangeal joint.
IV. Vascular interventional treatment
Vascular lesions of diabetic foot can be treated by vascular interventional surgery. Simply speaking, a catheter is inserted into the blood vessels of the lower limbs to show the vascular lesions, such as stenosis, occlusion, thromboembolism, etc., through imaging, and treat diabetic vascular lesions through balloon dilation technology, stent support technology and infusion of thrombolytic drugs through the catheter, so as to promote the healing of ulcers and solve the symptoms of coldness, numbness and pain in the lower limbs. Interventional treatment is now accepted and recommended by a wide range of international experts.
Diabetic foot vasculopathy is characterized by atherosclerosis of the lower limb vessels, often involving several arteries of both lower limbs, among which the tibiofibular artery of the lower leg is the most common (including the anterior tibial, posterior tibial and peroneal arteries). Due to the small diameter of the lower leg vessels and the large number of branches, once the narrowing or occlusion occurs, the treatment by conventional surgical bypass is often ineffective, and the chance of restenosis and re-occlusion after surgery is very high, so the long-term results are not very satisfactory.
Interventional therapy is a minimally invasive procedure that has been used in the cardiovascular field for many years, but the lack of a dilating balloon for the calf vessels previously limited the application of this technology. The introduction of small balloons has completely broken this limitation. The balloon is small and long, thick at one end and thin at the other, which is very compatible with the anatomical characteristics of the calf vessels.
For patients with arterial vessels in the lower leg that are not completely occluded and that meet the indications for this treatment, this small balloon is used to dilate, unblock and shape the arteries as far as the dorsalis pedis artery, allowing the ischemic limb to improve. The effect of this treatment is immediate, with an increase in skin temperature, a significant improvement in blood supply, enhanced pulsation of the dorsalis pedis artery, and significant relief of numbness and pain in the affected limb, and is characterized by the absence of incision, less pain, relative safety, and fewer complications.
In patients with vascular occlusion, the condition usually undergoes such a course. In the beginning, there is intermittent claudication, which is manifested by the inability to walk long distances, and when walking for a while, the legs feel painful and need to walk and take a break. In the second stage, not only walking will be painful, but also sitting will feel pain and some numbness, which will be properly relieved by massage with hands.
If it deteriorates further, the foot will ulcerate and the limb will gradually become necrotic. Many patients will also feel numbness and coldness in both legs, skin pigmentation and bruising, toenail deformation, hair loss, and even swelling, and they cannot feel the presence of both feet anymore. At the stage of intermittent claudication, treatment is most effective at this time if the patient can then detect the condition.
Of course, not all diabetic foot can receive this surgery, patients should be alert to the development of the disease, grasp the appropriate timing of surgery, in principle, should be the earlier the better the treatment, the more delayed the more serious the degree and length of vascular occlusion, the greater the difficulty of treatment, the worse the effect, surgical amputation will be difficult to avoid, and even threaten the lives of patients.
V. What are the dangers of diabetic foot?
Serious lower limb complications caused by diabetes include foot ulcers, infections, peripheral vascular disease, lower limb amputation and foot xeric osteoarthropathy. 15% of diabetic patients will have foot ulcers during their lifetime. The causes of diabetic foot ulcers are often multifactorial, with diabetic neuropathy, ischemic lesions or neuro-ischemic lesions being the most important factors in the formation of ulcers.
The causes of foot ulcers are usually peripheral neuropathy, minor trauma, foot deformity, edema, ischemic lesions, callus and infection. Studies have shown that the recurrence rate of ulcers is 34% in the first year, 61% in the second year, and 70% in the third year, and is even higher in patients with a history of amputation. The results of the follow-up of amputation in patients with cured ulcers are: the amputation rates in the first, third and fifth years are 3%, 10% and 12%, respectively; among those with a history of amputation, the re-amputation rates in the first, third and fifth years are as high as 13%, 35% and 48%.
Diabetes, as a metabolic disease, causes pathophysiological changes in the foot, including various neuropathies (sensory, motor and vegetative nerves), microangiopathy, increased plantar pressure, foot deformities such as claw toes, and abnormalities in vascular smooth muscle and vascular endothelial cell function. These many risk factors and local pathophysiological alterations interact and work together to lead to the formation of foot ulcers and injuries in diabetic patients.