Osteoarthritis, also known as degenerative arthritis, commonly known as “bone spurs” or “osteophytes”, is not actually an inflammatory disease, but is primarily a degenerative process that involves aging and wear and tear of the joints, especially the cartilage of the joints. Osteoarthritis represents the aging of the joints and is therefore called age-related arthritis. Osteoarthritis is the most common joint disease and the prevalence increases rapidly with age; more than 50% of people older than 65 years have radiographic evidence of osteoarthritis, but 25% will be symptomatic. 80% of people older than 75 years will be symptomatic. Osteoarthritis is the leading cause of pain and disability in older adults. The main cause of osteoarthritis is destruction of articular cartilage, softening and loss of elasticity of the articular cartilage matrix, loss of strength, and sclerosis or cystic degeneration of the subchondral bone and formation of bone fragments. The etiology of osteoarthritis has yet to be studied in depth. Currently, the disease is generally divided into two main types: primary and secondary. Primary is the most common. 1, age: age is the most risk factor, the incidence is directly proportional to age. With aging, repetitive use of the knee joint can stimulate inflammatory changes in the cartilage. In addition, the decrease in mucopolysaccharide content in cartilage in old age, the loss of chondroitin sulfate in the matrix, and the decrease in toughness make it vulnerable to mechanical injury and degenerative changes. Especially in more than 45 years old women are common, more than 50 years old women about 60% will be affected by this disease. 2, obesity: obese weight increases the load on the joints and due to changes in posture, gait, etc., resulting in changes in the biomechanics of the joints. Most obese people knee osteoarthrosis common site concentrated in the medial cartilage. Especially the lack of exercise obese people are more likely to suffer from this disease. 3, genetic: the prevalence of osteoarthritis in different races and populations is different and this inference is drawn. 4, estrogen: the incidence is higher in women and increases significantly after menopause, and is related to the discovery of estrogen receptors in articular cartilage. Therefore, many scholars inferred that the occurrence of osteoarthritis in female patients is related to estrogen. 5, climate factors: people who often live in a humid, cold environment have more symptoms. This may be due to the bottom of the temperature and poor blood circulation in the bone. 6, joint morphology: many patients with knee osteoarthritis have congenital knee valgus deformity or patellar subluxation deformity, etc.. The imbalance in the line of force makes these patients more susceptible to osteoarthritis than others of the same age. 7, joint strain: occupational types of work (miners, field workers, athletes, textiles, etc.) have a high prevalence. This means that strain on the joints can increase joint degeneration. Studies have shown that the incidence of knee pain and knee osteoarthritis in residents of buildings without elevators are higher than those in cottages. 8, other: joint trauma: fractures, dislocations, cruciate ligament and meniscus injuries can increase the local load and wear on the cartilage surface of the joint; severe trauma, especially fractures, may also change the function of other parts, leading to osteoarthritis. Rheumatoid arthritis, large osteoarthrosis, gout, diabetes, and scoliosis can all lead to osteoarthritis of the knee.