Ankle swelling is commonly caused by the following reasons: First, ankle sprain: ankle sprain occurs when going down steps, which can lead to ankle swelling, accompanied by pain and limited ankle movement, and it is difficult for the patient to continue walking and exercising with weight. Second, lower limb vascular lesions: such as varicose veins and deep vein thrombosis can lead to localized swelling of the ankle joint, mainly due to venous reflux obstruction, which increases the pressure in the surrounding soft tissue space, and the patient will have obvious limitation of ankle joint activities and a soreness and swelling of the lower limbs. Puffiness in the ankle joint should be diagnosed and treated early. Cardiac insufficiency should also be excluded to avoid delayed diagnosis and treatment in order to get complete relief of clinical symptoms.