There are many factors in life that can lead to the destruction of joint cartilage. Although the exact pathology is not clear, the following factors are closely related to the formation of osteoarthritis: (1) Weight: The higher the body weight, the greater the likelihood of osteoarthritis, because increased weight leads to increased weight bearing on the joints and mechanical damage to the structures within the joints from friction and compression when moving the joints. The mechanical damage to the structures in the joints from friction and compression will also increase. In addition, weight gain causes changes in posture, gait and exercise habits, which may also be the cause of osteoarthritis. (2) Age: Age is one of the most important factors in the treatment of osteoarthritis, and the incidence increases with age, because after old age, the muscular function of people decreases, the function of the peripheral nervous system is also decreasing, the reflexes are weakened, the nerve conduction time is long, which is often said that the elderly are more slow to respond, which may lead to uncoordinated nerve and muscle movements, thus more likely to cause muscle damage In addition, as the bone structure of the elderly changes with age, the inorganic content of the bone increases progressively (e.g., 50% in young people, but increases to 66% and 80% in middle-aged and elderly people, respectively), and the inorganic content of the bone becomes less elastic and tough, while the reduction of blood flow to the joints can lead to changes in the function of articular cartilage cells and cartilage properties. (3) Excessive application and injury: Most knee injuries, including cruciate ligament and meniscal tears, are a common cause of knee osteoarthritis, with osteoarthritic changes occurring in 89% of those with meniscectomy and osteoarthritis of the knee occurring in the vast majority of those with complete rupture of the anterior cruciate ligament. Osteoarthritis is also associated with a variety of sports, such as marathon sports (hip osteoarthritis) and soccer (knee and hip osteoarthritis). In addition some bad habits can also induce the occurrence of osteoarthritis, such as long-term work in front of the computer, poor sleep posture, the incidence of cervical osteoarthritis is particularly high in people with inappropriate pillows. (4) Hormone levels: Women after the age of 50 have a higher chance of developing osteoarthritis than men of the same age, which may be related to the reduced secretion of estrogen in postmenopausal women. Some studies have concluded that women who take estrogen have a smaller chance of developing osteoarthritis than those who do not. (5) Genetic factors: Genetic factors may also have an impact on the incidence of osteoarthritis, such as congenital structural abnormalities and defects (e.g. congenital hip dislocation, acetabular dysplasia and femoral head epiphyseal dislocation), abnormalities in cartilage or gut metabolism. Inheritance of obesity and osteoporosis, etc. can all contribute to an increased incidence of femoral arthritis.