The possible causes of bunion toe fracture and swelling of the foot and calf when walking on the ground after surgery include poor blood circulation and venous injury. 1. Poor blood circulation: Swelling of the foot and calf after walking on the ground after surgery for a fractured big toe may be due to poor blood circulation caused by localized injury. 2. Venous injury: Swelling of the foot and calf after walking on the ground after surgery is usually caused by localized venous injury after the fracture, resulting in poor venous return and some symptoms caused by localized bruising, which is usually accompanied by severe pain. There may be other reasons for the swelling of the foot and calf after walking on the ground after surgery. It is recommended that you go to a regular hospital in time to complete the relevant examinations, clarify the cause of the disease, and then carry out targeted treatment under the guidance of the doctor.