There are several common causes of lower limb swelling in sedentary conditions: a. In elderly patients, the valve closure of the deep veins of the lower limbs is incomplete, causing venous blood to reflux when sitting down due to gravity and accumulate in the blood vessels of the lower limbs, causing lower limb swelling. At this time, patients can take oral medication, wear elastic stockings on both lower limbs and avoid sitting and standing for a long time to reduce the reflux of blood in the lower limbs so as to improve the symptoms of swelling in the lower limbs. Secondly, for patients with varicose veins in the lower limbs, because a large amount of blood accumulates in the superficial blood vessels, it will cause obvious expansion of the blood vessels in the lower limbs and accompanied by swelling of the lower limbs. It is recommended that patients should have the superficial tortuous blood vessels stripped completely, which can completely solve the symptoms of swelling of lower limbs and avoid recurrence of patients’ disease.