If the swelling of the sprained foot does not go down for six months, there may be several reasons. First, poor recovery of the venous power of the lower extremity, resulting in blood pooling due to poor blood return to the lower extremity, leading to local swelling of the injury. This situation is often due to the long time of braking and fixation during the treatment, which causes the veins to atrophy and the lack of venous power. After six months, the venous power is slow to recover and has not been fully restored, resulting in persistent swelling. The second, also seen in the initial injury is more serious, resulting in extensive local soft tissue damage, tissue adhesions, scar contracture, ligament hypertrophy, these conditions will lead to poor local blood circulation swelling, also due to the initial injury decision. Third, it can also be seen in the recovery after sprain, recent heavy load work or long standing, long walking, resulting in poor blood circulation to the injury site, resulting in swelling. Generally, if this condition is not accompanied by pain and dysfunction, it is only necessary to pay attention to daily recuperation and regularly elevate the affected limb to reduce swelling, which can basically recover slowly.