Thromboangiitis obliterans
Introduction
Introduction to occlusive thrombotic vasculitis Thrombosis angiitis obliterans (TAO) is a kind of vascular inflammation that is different from arteriosclerosis and segmental distribution. The lesions mainly involve the middle and small arteries of the distal extremities. The pathologically mainly characterized by inflammatory cells. Invasive thrombosis, and less involvement of the vessel wall. Anyone who can make the peripheral blood vessels persistently paralyzed may be a causative factor. The cause may be comprehensive, the blood vessels may be persistent, affecting the blood supply of the nourishing blood vessels in the wall, and may cause ischemic damage to the wall. , leading to inflammatory reactions and thrombosis, which form the basis of the occurrence and development of this disease. basic knowledge The proportion of illness: 0.03% Susceptible people: no specific people Mode of infection: non-infectious Complications: neuritis
Cause
Causes of occlusive thrombotic vasculitis
(1) Causes of the disease
The etiology of thromboangiitis obliterans is still not fully understood. It is generally believed to be caused by a combination of factors, including:
Smoking (20%):
Refers to active and passive smokers, nicotine can cause vasoconstriction. According to statistics, 80% to 95% of patients have a history of smoking. Smoking cessation can improve the condition, and then relapse after smoking. Although smoking is related to this disease, Close, but not the only cause, because women smokers, the incidence is not high, and a small number of patients never smoke.
Cold and infection (10%):
Cold damage can cause vasoconstriction, so the incidence rate in the north is significantly higher than that in the south. Since many patients have skin fungal infections, some scholars believe that it affects human immune response and can increase fibrinogen content in the blood. Thrombosis occurs, but some susceptible people are often exposed to cold environments due to work relationships, and although there are fungal infections, the incidence is not high, so it is not possible to confirm the main cause of cold and infection. It may be an inducement that aggravates vasospasm.
Sex hormones (15%):
Most of the patients are male, and they are all young and young, which may be related to prostate dysfunction and vasomotor dysfunction.
Vascular dysregulation (11%):
The autonomic nervous system's dysregulation of endogenous or exogenous stimuli can cause the blood vessels to be paralyzed, which can lead to thickening of the wall and thrombosis.
Trauma (20%):
A small number of patients have a history of physical injury, such as crushing, strenuous exercise, long-distance walking, etc., the incidence may be related to vascular injury, but some minor trauma, not enough to cause limb vascular injury, and sometimes one side of the limbs mild trauma and other The pathogenesis of vasculitis in the limbs is difficult to explain with direct trauma violence. Some people think that after trauma, the nerve receptors are stimulated, which causes the central nervous system to become dysfunctional, which gradually loses the regulation of peripheral blood vessels, causing vasospasm and long-term paralysis. Causes a blocked blood clot.
Immunology (20%):
Clinical studies have shown that patients with vasculitis have special cellular and humoral immunity against human arterial antigens, anti-arterial antibodies in serum, and various immunoglobulins (IGM, IGG, IGA) and C3 complexes found in the blood vessels of patients. The presence of antinuclear antibodies in serum, no anti-mitochondrial antibodies, abnormal human leukocyte antigens and the presence of these autoantibodies suggest that the disease may be an autoimmune disease. In recent years, it has been reported in the literature that patients with arterial antigens are tested for complement fixation. 44.3%, the positive rate is higher when the condition is in acute activity.
In short, from a clinical point of view, any person who can make the peripheral blood vessels persistently paralyzed may be a causative factor. The cause may be comprehensive, and the blood vessels may be persistent, affecting the blood supply of the nourishing blood vessels in the wall. Ischemic damage to the wall of the tube leads to inflammation and thrombosis, which form the basis of the occurrence and development of this disease.
(two) pathogenesis
1. Pathological features Vasculitis is a disease of peripheral blood vessels. The inflammatory reaction in the whole vascular layer has intracavitary thrombosis and luminal obstruction. Its characteristics are as follows:
(1) The lesion mainly invades the blood vessels of the lower limbs, and the progress of the disease can invade the upper limbs. Although the internal organs such as the heart, brain, intestines and kidneys can be involved, it is extremely rare. Among the 261 cases in Shanghai Zhongshan Hospital, 21 cases were affected by the upper and lower limbs. One case occurred alone in the upper limbs.
(2) The lesions mainly involve small and medium-sized arteries, such as anterior iliac crest, posterior iliac crest, foot, sputum, sputum, ulnar and palm, etc., other large arteries such as femoral and radial artery lesions are less common, according to a group of 198 Patients with vasculitis underwent bilateral femoral angiography analysis. Analysis of 105 patients with 210 arterial angiography showed that anterior, posterior, and radial occlusions accounted for 90%, 80%, and 50%, respectively. Half of the patients were not occluded. In 40% of patients, except for calf arterial occlusion, the femoral artery was also involved. The femoral artery disease developed from the calf artery lesion to the proximal end. About 40% of the calf vascular occlusion types were similar on both sides. The above disappeared in the occlusion of the distal arterial trunk.
(3) The whole vascular wall of the lesion is non-suppurative vasculitis, with extensive lymphocytic infiltration and proliferation of endothelial cells and fibroblasts in the full-thickness vessel wall, and less neutrophil infiltration, occasionally giant cells. In the early stage, there is intraluminal thrombosis. The initial stage of thrombosis is red or brown, then it turns pale yellow, contains many endothelial cells and fibroblasts, and later thrombosis, accompanied by small revascularization of the lumen of the blood vessels. Sympathetic nerves can produce peri-inflammation, neurodegeneration and fibrosis, and the pathological changes of venous involvement are roughly the same as those of arteries.
(4) The lesions are segmental and often have a segmental distribution. There is a normal wall of the intima between the segments, and the boundary between the lesion and the normal part is distinct.
(5) A small number of patients in the late stage of the disease, the vessel wall and perivascular tissue are extensively fibrotic, arteries, veins and nerves can be surrounded by fibrous tissue, forming a collateral vein around the formation of a collateral.
(6) At the same time of vascular occlusion, although the collateral circulation can be gradually established, it is often not enough to compensate, so the affected limbs are insufficiently supplied with blood, pain, dysfunction and dystrophies of bones and soft tissues, muscle and skin atrophy, osteoporosis or Necrosis, osteomyelitis, fat absorption and fibrosis of the feet and toes, thickening of the nails, slow growth, hair loss, increased toe capillaries, expansion without tension, late gangrene and ulcers, secondary infections, Diffuse cellulitis, tendon sheath abscess or ascending lymphangitis, severe cases of neurofibrosis, and even the separation and degeneration of nerve fibers and their cell bodies.
2. Pathological process The pathological process of thromboangiitis obliterans can be divided into acute phase, advanced phase and terminal phase.
(1) acute phase: the pathological changes in the acute phase are the most characteristic and diagnostic value, mainly manifested in the inflammatory reaction of the full layer of the blood vessel wall, accompanied by thrombosis, luminal occlusion, polymorphonuclear leukocyte infiltration around the thrombus, There is a microabscess formation.
(2) Progression period: In the advanced stage, it is mainly the occlusion of occlusive thrombus, and a large number of inflammatory cells infiltrate into the thrombus, while the inflammatory reaction of the vessel wall is much lighter.
(3) End-stage: The main pathological changes in the terminal phase are the recanalization after thrombusization, the revascularization of the outer wall of the vessel wall, and the fibrosis around the blood vessels, and the sympathetic nerves of the vessel wall can also develop nerves. Peripheral inflammation, neurodegeneration and fibrosis, pathological changes in this period are often lacking in characteristics, and are easily confused with late changes in vascular occlusion caused by arteriosclerosis. In general, thrombosis, massive inflammatory cell infiltration and hyperplasia are thrombotic occlusive vessels A characteristic pathological change in inflammation.
Prevention
Occlusive thromboangiitis prevention
The cause of this disease is unknown, but some factors can induce the disease, and can cause the development of the disease, so take proactive measures to stabilize the disease and reduce symptoms.
1. Absolute smoking is an important measure to prevent and treat this disease.
2. The feet are clean and dry to keep the feet clean and prevent infection. Because wet and cold is more harmful to the disease than dry and cold, it is better to keep the feet dry. Because the affected part has poor blood circulation, even slight trauma can easily cause tissue necrosis and ulceration. Formed, so avoid any form of trauma.
3. Keep warm and keep warm in the foot, whether it is at work or rest, to improve blood circulation in the foot, but not overheat, so as not to increase oxygen consumption.
4. Position change and foot exercise should change position at any time to facilitate blood circulation, and usually perform foot exercise (Buerger exercise) to promote collateral circulation of the affected limb. The method is: the patient is lying flat and raising the affected limb 45 °, maintain 1 ~ 2min, then two feet to the side of the bed 2 ~ 5min, while the two feet and its toes to move around 10 times, then rest the limbs rest for 2min, so repeated 5 times, several times a day.
5. Avoid applying vasoconstrictor drugs.
Complication
Complications of occlusive thrombotic vasculitis Complications
Tissue dystrophy can be complicated by ischemic neuritis. If the arterial lumen is completely occluded, the local tissue blood supply is completely lost, resulting in ulceration and gangrene.
Symptom
Symptoms of occlusive thromboangiitis Common symptoms Limb numbness Muscle atrophy Partial skin of the limbs... Skin pale lower extremity Skin nutritional changes Nodules Intermittent claudication Limb distal numbness, ... Hyperthermia chilly calf ulcer
The onset of the disease is concealed, the disease progresses slowly, and it is often a periodic episode. After a long period of evolution, the condition is gradually aggravated. The clinical manifestation is mainly caused by the decrease of limb ischemia caused by blood flow after limb artery occlusion, and the severity of the disease. It is different depending on the location of the vascular occlusion, the extent of the collateral circulation, and the presence or absence of localized infection.
Symptom
(1) cold and paresthesia: the affected limb is cold, cold is a common early symptom, the surface temperature of the affected part is reduced, especially the toe (finger) end is most obvious, because the nerve endings are affected by ischemic influence, the affected limb ( Toe, refers to the feeling of sensation, acupuncture, numbness or burning.
(2) Pain: It is also an early symptom, which originates from arterial spasm. It is caused by stimulation of nerve receptors in the blood vessel wall and surrounding tissues, and the pain is generally not severe.
(3) Intermittent claudication: a special manifestation of ischemic pain caused by occlusion of endarteritis and thrombosis, that is, when the patient walks for a long time, the calf or foot muscles are painful or pumping. Pain, if you continue to walk, the pain is aggravated, you have to stop, after a short break, the pain is relieved quickly, and then the pain reappears after walking. This symptom is intermittent claudication. As the disease progresses, the walking distance is gradually shortened, and the rest is stopped. Time is growing.
(4) Resting pain: The condition continues to develop, the arterial ischemia is more serious, and the pain is severe and persistent. Even if the limb is at rest, the pain is still more than that. It is called rest pain, especially at night, when the limb is raised, it is aggravated. After the drooping, the pain can be slightly relieved. The patient knees and knees to sit and sleep, staying up all night, sometimes even sagging the affected limb to the bed to relieve the pain. If the infection is complicated, the pain is more severe.
(5) Changes in skin color: skin is pale due to arterial ischemia, accompanied by a decrease in superficial vascular tone and thinning of the skin, flushing or cyanosis may occur.
(6) Arterial pulsation weakened or disappeared: the pulsation of the dorsal or posterior tibial artery, the ulnar or radial artery, weakened or disappeared as the lesion progressed.
(7) Nutritional disorders: long-term chronic ischemia of the affected limbs, malnutrition in the tissues, manifested as dry skin, desquamation, chapped, hair loss, thickening of the toe (finger), slow deformation and growth, relaxation of the calf muscles, atrophy, The circumference is thinner, the disease develops worse, the tissue of the extremity is severely ischemic, and eventually ulcers or gangrene are produced, mostly dry gangrene, which first appears at the end of one or two toes or next to the toenail, then involves the entire toe and begins. When the toe end is dry and black, the necrotic tissue is detached and forms a long-lasting ulcer. At this time, the pain in the extremities is more severe. The patient can not fall asleep day and night, the appetite is reduced, the weight is weak, the complexion is pale and even anemia. If the infection is concurrent, it is wet and gangrene. , there are hyperthermia, chills, irritability and other symptoms of toxemia.
(8) ambulatory thrombotic superficial phlebitis: about 1/2 of the patients before or during the onset, in the calf or superficial veins of the foot, repeated migratory thrombophlebitis, manifested as superficial The veins are red, nodular, with mild pain. After 2 to 3 weeks of acute attack, the symptoms subsided and repeated over time, and the condition was not noticed by the patient for several months or years.
2. Physical examination
(1) Burger test: the patient was placed in a supine position, and the lower limbs were raised 45°. After 3 minutes, the skin of the positive person was pale, numbness or pain. When the patient sat up, the skin of the foot became flushed or appeared after the lower limbs drooped. Local purpura, this examination indicates that there is a serious lack of blood supply to the affected limb.
(2) Allen test: The purpose of this test is to understand the occlusion of the hand artery in patients with thromboangiitis obliterans, that is, to suppress the patient's radial artery, so that it can repeatedly punch and punch the fist, if the original finger ischemic area skin color recovery, proof The collateral artery-derived collaterals are sound, and conversely suggest the presence of distal arterial occlusion. Similarly, this test can also detect the soundness of the collateral artery of the radial artery.
(3) nerve block test: that is, through spinal anesthesia or epidural anesthesia, block the lumbar sympathetic nerve, if the skin temperature of the affected limb is significantly increased, suggesting that the distal limb ischemia is mainly caused by arterial spasm, otherwise it may have There is arterial occlusion, but this test is an invasive procedure and is rarely used clinically.
3. Clinical stage according to the severity of the disease, the clinical process is generally divided into three phases: the first phase, the ischemic phase; the second phase, the dystrophic phase; the third phase, the gangrene period, master the clinical stage to identify the severity of the disease It is important to choose a reasonable treatment.
(1) Ischemic period: in the early stage of the disease, the affected limb is numb, cold, cold, sore, followed by intermittent claudication. When examined, the skin temperature of the affected limb is slightly lower, the color is paler, and the back is (or) the posterior tibial artery pulsation is weakened, and the migratory thrombotic superficial phlebitis may occur repeatedly. This period causes ischemic causes, and the functional factor () is greater than the organic factor (occlusion).
(2) dystrophic period: for the progression of the disease, the pain turns into persistent rest pain, the pain at night is severe, the patient can't fall asleep while sitting on the foot, the skin temperature drops significantly, obviously pale or flushing, purple spot, dry skin, no Sweat, toenail thickening deformation, calf muscle atrophy, foot and/or posterior iliac artery pulsation disappeared, various arterial function tests were positive, after the lumbar sympathetic block test, skin temperature rise may still occur, but not To normal levels, this stage of the disease is an arterial occlusion, and the collateral circulation can still maintain the survival of the affected limb.
(3) gangrene period: in the late stage of the disease, the toe (finger) end of the affected limb is black, dry, dry gangrene, ulcer formation, severe pain, sitting on the knees and feet, day and night, can not fall asleep, weight loss, anemia, such as concurrent infection Become wet gangrene, plus the above position, can cause swelling of the affected limb, severe cases of systemic poisoning symptoms and life-threatening, this period of arterial complete occlusion, collaterals are not enough to compensate for the necessary blood supply, necrotic limbs can not survive .
In clinical practice, the diagnosis of thromboangiitis obliterans is generally easier, but early diagnosis sometimes becomes difficult.
Examine
Examination of occlusive thrombotic vasculitis
1. Determination of blood coagulation and fibrinogen factor Determination of antithrombin III (AT-III), plasminogen (Fibrinoben), -macroglobulin (2-Macroglobulin), etc. to understand whether the blood is hypercoagulable.
2. Histopathological examination.
3. Blood, urine and liver and kidney function tests to understand the patient's general condition, determine blood lipids, blood sugar and blood coagulation indicators, to determine whether there is a tendency to hypercoagulability and other risk factors.
4. Rheumatoid immune system examination may exclude other rheumatic diseases, such as RF, CRP, antinuclear antibodies, complement, immunoglobulin and the like.
5. Non-invasive vascular examination is to understand the patency of the blood flow of the affected limb by electrical impedance blood flow tracing. By measuring the blood pressure of each segment of the upper and lower limbs, the / index (ABI) is calculated to assess the degree of ischemia of the affected limb. In the plane of vascular occlusion, the normal ABI should be 1. If ABI<0.8 indicates the presence of ischemia, if the ABI value of the two segments decreases by 0.2 or more, it indicates that the vessel has stenosis or occlusion. In addition, this test can also As an objective indicator of follow-up efficacy.
6. Ultrasound examination can visually display the blood vessels of the affected limbs, especially the extent and extent of the distal movements and veins of the limbs. Combined with color Doppler flowmetry, the diameter and flow rate of the blood vessels can also be measured. Guiding significance.
(1) Two-dimensional ultrasound: Gray-scale ultrasound shows thickening of the intima in the arterial wall, and the intimal roughness is "worm-like"; in severe cases, the entire lumen can be occluded, and most of the lesions below the radial artery are present. Segmental, no plaque formation at the lesion, and the intima of the upper and lower arteries are often normal.
(2) Color Doppler flow imaging: showing that the narrow blood flow channel is thin, uneven, color is color, severe stenosis or occlusion, color Doppler visible darkening or disappearance of blood flow, distal artery The color of the bloodstream is also dim.
(3) Doppler flow velocity curve: pulse Doppler shows increased blood flow velocity in the stenosis and distal segment, the curve is widened, the reverse blood flow disappears, and when severe stenosis or occlusion, pulse Doppler shows low velocity blood flow, The distal arteries may have a low-speed, low-resistance blood flow curve (Tardus-parvus phenomenon) in which the diastolic flow rate is increased and the systolic flow rate is decreased.
7. Magnetic resonance angiography (MRA) This is a non-invasive angiography technology newly developed in recent years. Based on magnetic resonance scanning, image integration is performed by using intravascular blood flow phenomena. It shows the lesions and stenosis of the affected limbs and veins. The imaging effect can replace angiography (especially the arteries of the lower extremity femoral condyle) to some extent, but the MRA has poor imaging effect on the peripheral blood vessels of the extremities. This limits the use of MRA in patients with thromboangiitis obliterans.
8. Digital subtraction angiography (DSA) It is generally believed that angiography is not necessary for the diagnosis of thromboangiitis obliterans, but the choice of diagnosis and treatment of suspicious cases (especially surgical methods) is still very The value of the auxiliary examination method, the typical signs are mostly segmental stenosis or occlusion of the limb artery, the lesion is mostly confined to the distal part of the limb, while the proximal vascular is not abnormal, from normal to the diseased vessel segment is suddenly changed The lesion is near, the distal artery is smooth, flat, showing normal morphology, visible "root", "spider" and "spiral" collateral vessels (Figure 2), in addition, DSA examination can also show There is a rich collateral circulation around the occluded blood vessels, and it can also rule out the presence or absence of arterial embolism.
Diagnosis
Diagnosis and diagnosis of occlusive thrombotic vasculitis
Diagnostic criteria
1. Diagnostic criteria In 1995, the diagnostic criteria for thromboangiitis obliterans revised by the Committee on Peripheral Vascular Diseases of the Chinese Association of Integrative Medicine was:
(1) Almost all men, the age of onset is 20 to 45 years old.
(2) Chronic limb arterial ischemia, such as numbness, cold, intermittent claudication, congestion, changes in nutritional disorders, etc., often involving the lower extremities, fewer upper limbs.
(3) 40% to 60% have a history and signs of migratory thrombophlebitis.
(4) Various examinations have shown that the arterial artery is occluded, and the location of the stenosis is mostly in the radial artery and its distal artery (often involving the small and medium arteries of the limb).
(5) Almost all have a history of smoking, or have a history of cold.
(6) Exclusion of limb arteriosclerotic occlusive disease, diabetic gangrene, arteritis, limb arterial embolism, Raynaud's disease, traumatic arterial occlusive disease, connective tissue disease vascular disease, cold injury vascular disease and allergic vasculitis .
(7) During the active period of the disease, the patient's blood IgG, IgA, IgM, anti-arterial antibodies, immune complex positive rate increased, T cell function index decreased.
(8) Arteriography:
1 lesions are more common in the iliac femoral artery and its distal end.
2 Arteries are segmental occlusion, stenosis, and the arteries and proximal cardiac arteries between the occlusion segments are mostly normal.
3 There are many "roots" collateral circulation arteries at the proximal end of the arterial occlusion.
4 Arteries have no distortion, stiffness and plaque imaging.
The previous five items of clinical diagnosis are the main basis. If there are conditions, other indicators can be more accurate.
2. Special clinical manifestations of thromboangiitis obliterans should also pay attention to some special clinical manifestations of thromboangiitis obliterans, which is conducive to early diagnosis.
(1) Beginning with thrombotic superficial phlebitis: some patients often start with migratory thrombophlebitis, first invading the limb veins, intermittently recurring for several months, after several years or more than 10 years, the limb arteries are involved. Appearance of limb ischemia, if clinically do not pay attention to the characteristics of "recurrent migratory", often misdiagnosed as general thrombotic superficial phlebitis and delayed treatment.
(2) first joint pain: some patients first suffered from lower extremity joint pain, followed by limb ischemia and foot arterial pulsation disappeared, therefore, can be misdiagnosed as rheumatoid arthritis in the early stage of the disease, according to anti-rheumatic treatment .
(3) Single toe ischemic manifestations: Some patients first have a single toe or two toes. The toes are cold and cold, and they are pale or purplish red, sometimes intermittent, and the dorsal artery of the foot. The posterior tibial artery pulsates well, which is the first violation of the toe artery, causing paralysis or occlusion of the simple toe artery.
(4) First intermittent claudication: Patients often have initial symptoms of intermittent deafness. When walking, the calves and soles are tired and painful. After a little rest, they can be relieved or disappeared. After a period of time, limbs appear. When cold, cold, and color change, it will cause the patient's attention. Therefore, all young men with long-term smoking habits and intermittent claudication of the lower extremities should consider thromboangiitis obliterans, and should be further examined to confirm the diagnosis. , timely early treatment.
Differential diagnosis
According to the history of thromboangiitis obliterans, the following diseases should be identified in the diagnosis.
1. Arteriosclerosis obliterans This disease is more common in the elderly over 50 years old, often accompanied by hypertension, hyperlipidemia and other history of atherosclerotic cardiovascular and cerebrovascular disease (coronary heart disease, cerebral infarction, etc.), the lesions mainly involve large, medium Arteries, such as the abdominal aorta, radial artery, and femoral artery, can be seen by X-ray examination of irregular calcification of the arterial wall. Angiography shows arterial stenosis, occlusion, distortion, angulation or worm-like changes.
2. Acute arterial embolism is sudden onset, and there is often a history of rheumatic heart disease with atrial fibrillation. In the short term, the distal limb may be pale, painful, without veins, numbness, paralysis, and angiography may show a sudden interruption of arterial continuity. The unaffected arteries are smooth and flat, and cardiac ultrasound can also clarify the source of proximal emboli.
3. Multiple arteritis is more common in young women, mainly involving the aorta and its branch arteries, including the carotid artery, subclavian artery, renal artery, etc., which is characterized by arterial stenosis or occlusion, and produces corresponding ischemic symptoms. During the active period, the erythrocyte sedimentation rate may increase, and other rheumatoid indicators may be abnormal.
4. Diabetic gangrene should be differentiated from acral ulcer or gangrene in the late stage of thromboangiitis obliterans. Diabetes often has a history, blood sugar, elevated urine sugar, and mostly wet gangrene.
5. Raynaud's disease is more common in young women. The main manifestations are the pale upper limbs with pale hair, purple and flushing. The skin color is normal during the interictal period. The distal arteries of the affected limbs are normal, and few gangrene occur.
6. Autoimmune diseases are first identified with CREST syndrome and scleroderma. Both diseases can cause peripheral vascular disease, but at the same time there are pathological changes in the skin, and serum Scl-70 and anti-centromere antibodies are positive. Combined with the microcirculation changes of the nails of the nails, it can be identified, followed by the differentiation of vasculitis caused by SLE, rheumatoid arthritis and other systemic rheumatoid diseases, mainly through medical history collection, some characteristic laboratories. Check and organize biopsy to identify.
7. Nodular arterial inflammation This disease mainly invades the middle and small arteries, and the limbs may have ischemic symptoms similar to thromboangiitis obliterans. The characteristics are: extensive lesions, often involving the kidney, heart and other internal organs, subcutaneous The nodules of the arteries often have a weaker and hemorrhagic erythrocyte sedimentation rate, and the blood tests are hyperglobulinemia ( and 2). A biopsy is needed for the diagnosis.
8. Idiopathic arterial thrombosis is rare, and it can occur in other diseases, such as systemic lupus erythematosus, nodular arteritis, rheumatoid arthritis and other connective tissue diseases or polycythemia. After surgery or arterial injury, the onset is more likely to cause extensive necrosis.
9. Other non-vascular diseases such as frostbite, flat foot, gout, neurotrophic ulcer, sciatica, arthritis, peripheral neuritis, etc. should also be noted.
