Lower extremity venous thrombosis can be determined by ultrasound of the lower extremity veins and coagulation function. Lower extremity venous thrombosis is usually characterized by painful swelling of the lower extremities, a sudden increase in skin temperature, and in some cases dilatation of the superficial veins, and the swelling and pain worsens as the patient walks. If the above symptoms occur, it is recommended to go to the hospital to measure the coagulation function and do ultrasound examination of the veins of the lower extremities to determine whether the lower extremity venous thrombosis, and after diagnosis, it is necessary to carry out surgical treatment in a timely manner. It is recommended that patients with lower extremity venous thrombosis should pay attention to bed rest, do not do strenuous exercise, to prevent thrombus fall, resulting in pulmonary embolism. Therefore, it is recommended that patients should follow the doctor’s instructions, under the guidance of the doctor to carry out the corresponding treatment, so as to achieve early detection and early treatment.