Painful knee joints with limited movement are a common cause of orthopedic outpatient visits, and most patients have been seen by multiple hospitals, with some doctors diagnosing “osteophytes of the knee” based on knee x-rays alone. Is osteophytes the cause of knee pain? As the largest and most complex joint in the body, the knee joint is the most degenerative of the joints in the limbs due to its weight bearing and high mobility. Most of the common clinical causes of knee pain and swelling are due to synovial hyperplasia, degeneration of the meniscus, or the exfoliation and exposure of the articular cartilage due to prolonged disease. The pain is not caused by the usual “bone spurs” that irritate the joint. This type of disease can generally be treated with joint braking and rest, physical therapy, oral anti-inflammatory and pain-relieving drugs such as Fotarim and Fenbid, or intra-articular injection of sodium hyaluronate, and physical therapy. If there is a large amount of fluid in the joint, the fluid should be pumped under aseptic conditions and injected with prednisolone and other drugs. If the joint swelling and pain persist or recur, arthroscopic treatment of the knee may be considered. In some patients, the knee joint is severely deformed and the x-ray shows narrowing of the joint space. This means that the articular cartilage has been destroyed and damaged, and conservative treatment is basically ineffective. The only treatment is surgery to replace the joint.