Blood flow disorder means that blood circulation cannot be completed normally, and blood flow disorder is manifested as arterial blood flow disorder and venous blood flow disorder, which have different clinical manifestations. Arterial dyscrasia will show coldness and pale skin on one side of the limb, because the arterial dyscrasia will narrow the lumen of the artery, and the blood supply to the distal limb of the artery will be reduced, which will show pallor and cold skin, and in serious cases, necrosis of the limb will occur, such as diabetic patients often have necrosis of the limb due to the blockage of blood vessels. Venous blood flow disorders are mainly manifested as venous reflux disorders, mainly manifested as swelling on one side of the limb, accompanied by painful symptoms, so different blood flow disorders will have different clinical manifestations.