Bruised and swollen knee may be caused by patellar fracture, ligament injury, etc. It is necessary to take general measures to adjust to the cause of the disease, and medication, surgical treatment and rehabilitation treatment are needed if necessary. 1. Soft tissue injury: If the knee is swollen with bruises due to soft tissue injury, first of all, it needs to be immobilized and the affected limb needs to be elevated, and it also needs to be bandaged with pressure. In addition, local application of diclofenac diethylamide cream, ketoprofen gel, etc. is also needed. For patients with open wounds, debridement and suturing are needed. 2. Ligament injury: If there is a ligament injury in the knee area, it will also show up as bruising and swelling of the knee. At this time, the patient should rest in time after the injury, and within 72 hours after the injury need to ice and pressure bandage, while the patient also needs to elevate the affected limb. In addition, patients with pain need to follow the doctor’s instructions with acetaminophen, indomethacin and other non-steroidal painkillers. If the patient’s joint ligament damage is large, arthroscopic minimally invasive surgical treatment is needed. 3. Patellar fracture: for patellar fracture caused by knee bruising and swelling need to use the lower limb support or plaster brace to fix the knee joint, and then within 72 hours after the injury need to be iced, and at the same time also need to carry out the knee joint braking. If the patient has fracture displacement, partial or total patellar resection and wire tension band suture are required. In addition, the patient needs to carry out straight leg raising and knee extension training in the first week after the operation, and also needs to carry out gradual resistance training in 6 weeks after the operation. It is recommended that patients with knee bruising and swelling need to consult a doctor in time and follow the doctor’s instructions.