The swelling of broken foot may be caused by the serious injury or due to the combination of vascular disease of the lower limbs. 1.serious injury: broken foot belongs to the more common injury in daily life, most of the patients with broken foot edema is caused by soft tissue injury, under normal circumstances, edema will gradually subside in about 7-10 days. Under normal circumstances, the edema will gradually subside in 7-10 days. If the edema does not subside for a long time after breaking the foot, it may be caused by more serious injuries, such as tearing of ligaments around the ankle joint and fracture of the ankle joint. 2. Lower extremity vascular disease: patients with lower extremity vascular disease may also have edema that does not subside for a long time after breaking their feet. Lower limb vascular diseases may lead to increased permeability of lower limb blood vessel wall, abnormal function of venous valves and other pathological changes, causing long-term venous blood stagnation, resulting in edema for a long time. For example, varicose veins of the lower limbs, thrombotic occlusive vasculitis and so on. The swelling of the broken foot does not subside may also have the foot for a long time low hanging, improper braking, premature hot packs and other reasons, it is recommended to go to the hospital in time, improve the examination to clarify the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment.