The popliteal artery is located deeper, adjacent to the popliteal surface of the femur and the posterior part of the knee capsule. It runs obliquely outward along the outer edge of the semitendinosus muscle to the level of the femoral condylar fossa in the middle of the posterior knee, and then vertically downward to the inferior edge of the popliteal muscle, where it divides into the anterior tibial artery and the posterior tibial artery. The former enters the anterior region of the calf via the superior border of the interosseous membrane, while the latter goes to the posterior region of the calf via the deep surface of the tendon arch of the hallux valgus muscle. In addition to the muscular branches of this artery, there are five articular branches, namely the superior medial and lateral knee arteries, the middle knee artery and the inferior medial and lateral knee arteries, which all participate in the arterial network of the knee. The upper popliteal artery is closely related to the popliteal surface of the femur. Weak pulsation of the dorsal foot and posterior tibial artery: diabetic foot is a disease state in which ulceration and gangrene occur in the lower extremity of diabetic patients due to neuropathy, inadequate arterial perfusion caused by macrovascular and microvascular lesions, and weak or absent pulsation of the dorsal foot and posterior tibial artery, local skin dystrophy, decreased skin temperature, abnormal color, pale when the finger is high on the affected glue, and drooping with The foot is prone to chronic ulceration. Diabetic foot is a serious complication of diabetes mellitus, and is one of the important causes of disability and even death in diabetic patients, which not only causes pain to patients, but also adds a huge economic burden to them. Loss of dorsalis pedis artery pulsation: Lower limb atherosclerosis is often accompanied by numbness of the extremities and loss of dorsalis pedis artery pulsation. This disease is mostly seen in middle-aged and elderly people, often accompanied by a history of hypertension. Early symptoms are mainly intermittent claudication, and pain at rest is a sign of severe ischemia of the lower limbs, often accompanied by numbness of the extremities. Late stage ulceration and gangrene of the extremity may also occur. Physical examination may reveal a decrease in skin temperature of the extremity, and a weakened or absent distal arterial pulsation in the narrowed or occluded segment of the artery. Doppler ultrasound and angiography can be used to determine the site, degree and extent of the disease and help in the selection of surgical methods.