Clinical some patients suddenly without any signs of leg pain, and even cold, numbness, impaired mobility and other symptoms, often choose to go to the orthopedic department, the results of a series of orthopedic examination is not abnormal. At this time, the clinically experienced doctors will give the patient line lower extremity vascular examination, do not know, a check shock: lower extremity “stroke” (lower extremity arterial embolism)! Lower extremity arterial embolism refers to emboli from the heart, proximal arterial wall, or other sources of arterial blood flow into the artery and embolize the distal smaller diameter branch arteries, which in turn causes ischemia in the artery-supplied limbs, most commonly in the lower extremities, and in severe cases, will ultimately lead to amputation. Therefore, the clinical etiology of arterial embolism lies in the “embolus” blocking the blood vessels. I. Clinical causes 1, according to the embolus type: blood clots in the blood vessels, air, fat, cancer embolus, broken catheters, etc. can become embolus blockage of lower extremity arteries. 2.According to the source of embolus: (1) cardiac origin: about 90% of embolus originates from the heart, atrial fibrillation has a close relationship with embolus, and most of the embolus caused by atrial fibrillation originates from the thrombus attached to the wall of the left atrium. Rheumatic heart disease, coronary heart disease, bacterial endocarditis, artificial heart valves can produce emboli of cardiac origin. (2) Vascular origin: aneurysm, artificial blood vessel lumen, atherosclerotic plaque detachment (3) Medical origin: fractured catheter, embolic material, implanted material, etc. (4) Others: cancer embolism, amniotic fluid embolism, air embolism, etc. II. Pathological manifestations 1. Early vasospasm, endothelial cell degeneration, thrombus formation. 2.6~12h tissue necrosis. 3, Ischemia reperfusion injury. Clinical manifestations—5 Ps Typical manifestations of acute arterial embolism include the “5P” signs, i.e., pain (pain), numbness (parasthesia), dyskinesia (paralysis), pulselessness (pulselessness) and pallor (pallor). 1, pain Most patients with acute arterial embolism complain of severe pain in the affected limb, the pain site depends mainly on the site of embolism, generally acute arterial embolism to the far plane of the affected limb pain, pain intensified during activities. With the formation and extension of secondary thrombus, the pain plane can be developed to the proximal end. 2, numbness, dyskinesia As the nerve tissue is quite sensitive to ischemia, thus in the early stage of acute arterial embolism, that is, the affected limb sensory and motor impairment. The manifestation of the affected limb distal sock-like sensory loss area, the proximal end of the sensory loss area, and then the proximal end of the sensory hypersensitivity area, the sensory loss area plane is lower than the plane of the arterial embolism. In addition, the affected limb has muscle weakness, paralysis and different degrees of ptosis, when the eventual muscle necrosis and the performance of the complete loss of motor function, suggesting that the affected limb is about to have irreversible changes. 3, pallor, syncope cold can be seen between the pale skin scattered cyanotic plaques. The limbs are severely ischemic, so the skin is cold, especially at the extremities. It should be pointed out that usually the affected limb skin color, skin temperature changes in the plane than the embolism site is lower than a palm width to two joints plane. 4, arterial pulsation weakened or disappeared embolism and arterial spasm, resulting in embolization of the plane distal to the arterial pulsation significantly weakened or disappeared. Systemic effects: left heart failure, shock, hyperkalemia, eosinophilia, metabolic acidosis, renal failure. IV. EXAMINATION AND DIAGNOSIS Etiology+symptoms→diagnosis+examination→localized diagnosis Examination: ultrasound, MRA, CTA, DSA, ECG, cardiac X-ray, biochemical and enzymatic examination. V. Clinical treatment Principle: clear localization and diagnosis, active surgical treatment 1. Non-surgical treatment: mainly applicable to early stage, mild limb dysfunction, incomplete embolism; or as an adjunctive treatment to surgery. 2.Surgical therapy: it is the main means to treat acute arterial embolism. The time of ischemic necrosis of the limb is usually 4~8 hours, thus the earlier the surgery time, the better. Otherwise, the amputation rate rises with the prolongation of arterial embolism. ①Thrombolysis: Intervention under the arterial catheter thrombolysis is the main means of thrombolysis, compared with surgical treatment, the advantages are that it can dissolve the thrombus in the small arteries, gradually open the side branch to reduce ischemia-reperfusion injury, and less traumatic. Arterial thrombolysis ② arteriotomy Fogarty balloon catheter thrombolysis arteriotomy thrombolysis Therapeutic effect left lower extremity arterial embolism right lower extremity arterial embolism