There are local and systemic factors in foot swelling, mainly including the following: 1. Trauma leading to plantar fracture or soft tissue contusion, causing local bruising and swelling. 2. Long-term strenuous exercise or weight-bearing walking, leading to chronic strain on the plantar fascia, resulting in a sterile inflammatory reaction and local swelling caused by exudation of inflammatory substances. 3. 4.Venous thrombosis or varicose veins in the lower extremities, resulting in obstruction of blood flow to the lower extremities, causing significant bruising and swelling on the soles of the feet. 5.Sprain or dislocation of the ankle joint and damage to the local ligaments and tendons, affecting local blood circulation, can also cause swelling of the feet. 6.Malfunctioning of the heart, kidneys, hypothyroidism and hypoproteinemia This can cause edema on the bottom of the foot and the entire lower leg.