Surgical treatment of osteoarthrosis of the knee joint Mid-stage: If there is frequent interlocking of the knee joint, X-ray finds that there is a free body in the knee joint (proliferation of bone fragments fall off, free in the knee joint, causing interlocking), arthroscopic examination, free body removal and synovectomy can be performed. Late stage: Artificial total knee replacement Li Qiang, Department of Orthopaedics, Beijing Friendship Hospital Artificial knee replacement is to amputate the broken joint surface as required and replace it with an artificial knee surface, just like putting an iron palm on a horse’s hoof. This way, there is no pain in walking and the knee joint is normal in appearance. (Figure 13a,b,c) Figure 13a Placement of femoral prosthesis Figure 13b Placement of tibial prosthesis Figure 13c Placement of patellar prosthesis (patella is not usually replaced because of the thin patella in China) Typical cases in our hospital (Figure 14, Figure 15) Figure 14 Pre-operative severe O-leg deformity, X-ray revealed severe medial bone loss, intra-operative filling of the defect with autogenous bone (metal wedge spacers are routinely used) Figure 15 Post-operative 2 weeks The prosthesis was well positioned on postoperative radiographs, the knee was well aligned, and the inversion of the knee was corrected. Since the tibial spacer of the artificial knee is made of polyethylene, the wear resistance has not yet reached perfection. Therefore, the age for artificial knee replacement is generally set at 55 years or older. This is because the patient is not as active as a young person and the joint is not as worn out, so the surgery can be performed at this time to meet the needs of daily life while not having to worry about frequent re-replacement. However, the age is not absolute. If the knee pain is significant and conservative treatment does not work, the age can be relaxed, but the joint should be replaced with a better design and more wear-resistant material. Is there an upper age limit? Theoretically, no. As long as the medical condition can tolerate the surgery, it can be replaced. However, the older you are, the greater the risk of surgery and the less time you will have to enjoy the joint after replacement. Therefore, in this era of emphasis on quality of life, if it becomes necessary to replace the knee joint, early surgery is recommended. What factors are associated with the outcome of knee replacement surgery? A common question asked by patients is why some people walk like flies after surgery, while others still walk with crutches. Even though they all had surgery at a major hospital? As a joint surgeon, I know that the surgical technique is important for a good knee replacement surgery, but it is also important to have a well-designed and rigorous rehabilitation plan and full cooperation from the patient. The result of surgery is “6 points of work, 4 points of practice”. If the joint is well designed, but not placed on the normal knee joint force line, the wear and tear of the prosthesis is bound to increase, shortening the life of the prosthesis, and making it easier for conditions such as anterior knee pain and patellar dislocation to occur. In addition, for artificial knee replacement surgery, the sterile environment of the operating room is very demanding, i.e., it is required to operate in a class 100 laminar flow operating room (<100 colonies per cubic meter). Otherwise, in case of infection, the replaced joint must be removed. Therefore, it is important to go to a major hospital for surgery. The surgery is perfect, and if the patient cannot cooperate with the surgeon in rehabilitation exercises, the range of motion of the replaced knee joint is limited and it will not meet the requirements. Rehabilitation exercises are tough and cannot be achieved without pain. Of course, there are analgesic measures available to reduce pain. Finally, the psychological factors of the patient are also important. Pre-operative communication between the doctor, patient and family is important. The determination to do the surgery should be made by the patient himself, and the patient should respond to the surgery with a normal mind before the surgery and not have too high expectations. The higher the expectations, the higher the disappointment when the postoperative recovery period is difficult. Relief of pain and improvement of knee function is the main goal of surgery.