Foot a press a pit, usually this is called depressed edema, may be caused by the following aspects: 1, may be trauma or fracture, and the formation of local soft tissue swelling, usually in addition to local subcutaneous bruising, if the impact of the local lymphatic drainage, will not appear the formation of depressed edema; 2, it may be the lower limb of the lymphatic vessels are injured or local lymphatic drainage obstacles, resulting in; 3, may be chronic functional diseases, such as cardiac failure, renal failure, or systemic hypoproteinemia, in which cardiac failure and renal failure are usually the case, the heart and kidney failure, or systemic hypoproteinemia, in which the heart and kidney failure are usually the case, the heart and kidney failure. It may be caused by injury to the lymphatic vessels of the lower limbs or localized lymphatic reflux disorders; 3. It may be caused by chronic functional diseases, such as cardiac failure, renal failure, or systemic hypoproteinemia, in which cardiac failure and renal failure usually occur in both lower limbs at the same time, and systemic hypoproteinemia. In addition to bilateral lower extremity depression edema, there will be bilateral upper extremity and generalized edema.