There are many middle-aged and elderly patients with knee pain in the bone and joint surgery clinic, and osteoarthritis accounts for a large proportion of them. What is osteoarthritis and how does it occur? The surface of the normal knee joint is evenly covered with a layer of white cartilage tissue, which is very smooth and acts as less friction during knee movement. When a person reaches a certain age, obesity, overwork, trauma, etc., it causes aging, degeneration and wear of the joint cartilage, resulting in knee pain, swelling, difficulty walking and, in severe cases, joint deformation. We call this disease osteoarthritis, which can also be called degenerative arthritis. The disease is classified according to the specific area involved: patellofemoral arthritis, tibiofemoral arthritis, and total knee arthritis. MR can detect abnormal changes in the articular cartilage and subchondral bone at an early stage. Of course, we also need to differentiate it from other diseases that cause knee pain, such as meniscal injury, cruciate ligament injury, gouty arthritis, rheumatoid arthritis, compulsory spondylitis, synovial fold hyperplasia, and joint tuberculosis, before making a final diagnosis. The current treatment for osteoarthritis of the knee remains a triangular stepwise treatment. The first is general treatment, which includes reducing activity, avoiding high-intensity exercise, and reducing weight in obese individuals. Then comes the pharmacological treatment for early stage patients: 1. Non-steroidal anti-inflammatory and analgesic drugs, commonly used are celecoxib, diclofenac sodium, etc., can relieve pain in the acute phase with obvious effect. However, attention should be paid to taking them after meals to reduce gastrointestinal reactions. 2, nutritional cartilage drugs, commonly used glucosamine hydrochloride tablets, chondroitin sulfate, etc., no obvious side effects, need to be taken continuously for more than three months, those who have the conditions can be taken for a long time. 3, diacerein (Ambitin), which is the world’s first IL-1 inhibitor, can significantly slow down the course of the disease, reduce knee pain and improve joint mobility. It also needs to be taken orally continuously for more than three months. 4. Intra-articular injection of sodium vitrate, which acts as a lubricant in the joint and reduces friction between worn cartilage, while reducing the inflammatory response of synovial tissue, thus relieving pain and increasing joint mobility. Finally, surgical treatment is available. For patients who are not well treated with medication but are younger, have no significant narrowing of the joint space, and have normal joint force lines, arthroscopic debridement can be chosen. This procedure is less invasive, has a shorter hospital stay, and is quicker to get down to the floor, and can provide pain relief and improve joint mobility for most patients. Patients who are older, generally older than 60-65 years of age, have significant joint space narrowing, joint deformity, or poor arthroscopic results can opt for an artificial knee surface replacement. The procedure is now fully mature and is routinely performed in tertiary hospitals (prefecture-level hospitals), with an excellent rate of over 95%, and the patient can get out of bed and exercise with the aid of an abductor 5-7 days after surgery. With the continuous improvement of the surgical technique and the continuous improvement of the artificial knee prosthesis process, the service life of the prosthesis has also been improved as never before.