The blackening of the wound stitches may be due to the following two reasons: First, if the location of the wound cracks, or the location of the stitches needle holes appear blackened is a normal performance, because the epidermis appears crusted and formed a blackened situation. Generally after the wound is completely healed, the scab will naturally fall off, the wound has shown to be the case of healing. Second, there may be too tight stitches, resulting in local skin or soft tissue ischemia, or injury wound damage is very serious, poor blood circulation and ischemic necrosis of the skin and soft tissue. Usually this is a relatively large area of blackening, and in this case, it is necessary to remove some of the sutures to relieve the local pressure, so as to see if the necrotic skin can be preserved.