Osteoarthritis is also known as degenerative joint disease, degenerative arthritis, osteoarthrosis, hypertrophic or proliferative arthritis. It is generally believed to be related to local cartilage degeneration and stress abnormalities. In the early stages, the articular cartilage becomes yellow, rough, and loses its luster, followed by fissures, softening or exfoliation, and exposure of subchondral bone. Later, the perichondral tissue proliferates, bone redundancy forms, subchondral bone hardens, and the joint becomes enlarged, deformed, and movement disorders occur. Osteoarthritis is the most common joint disease in the middle-aged and elderly population and can develop in both men and women. 50% of the population over 60 years of age have osteoarthritis on X-rays, of which 35-50% have clinical manifestations; over 80% of the population over 75 years of age can have osteoarthritic symptoms. The disability rate of the disease can be as high as 53%. Osteoarthritis occurs in joints that carry a lot of weight and activity, such as the knee, hand, hip, and spine. There are two types of osteoarthritis: primary and secondary. Primary osteoarthritis is due to degeneration of joint cartilage and occurs after middle age, mostly in weight-bearing joints. Secondary osteoarthritis can occur in young adults and can be secondary to traumatic, inflammatory diseases or congenital diseases such as hip dislocation, hip dysplasia, ischemic necrosis of the femoral head, etc. Clinical manifestations of osteoarthritis of the knee joint Osteoarthritis of the knee joint, which is more common in women, may present with intra-articular friction sounds, joint interlocking and playing soft leg, in addition to joint pain, swelling, morning stiffness and restricted movement. The knee joint is moderately flexed and cannot be fully straightened, with joint effusion and, in severe cases, with internal and external knee deformity. X-ray shows narrowing of the joint space, dense subchondral bone, and cystic changes, lipoid hyperplasia of the joint edge, and sometimes intra-articular free bodies are seen. Clinical manifestations of hip osteoarthritis Patients with hip osteoarthritis may exhibit varying degrees of claudication, lower limb deformity, and pain in the hip, thigh and knee joints. Pain is often the first symptom to occur, swelling is usually not obvious, tension in the adductor muscles, reduced or limited range of motion in hip flexion, internal rotation and external rotation, and in severe cases, atrophy of the thigh muscles and shortening of the affected limb. X ray: sclerosis, cystic change or bone redundancy formation under the femoral head or acetabular cartilage, narrowing of the hip joint space. Treatment objectives To reduce or eliminate pain; to correct deformity; to restore or maintain joint function; to improve quality of life. Treatment (a) Non-pharmacological treatment 1. Patient education: self-care methods (including avoidance of bad posture and harmful movements and other triggers); attention to weight loss; appropriate exercise: such as swimming, cycling training; joint function training, such as knee joint in a non-weight-bearing position, practice flexion and extension activities to maintain maximum joint mobility; enhance peri-articular muscle training, such as hip osteoarthritis should pay attention to abductor muscle training; knee joint Osteoarthritis of the knee should pay attention to quadriceps training to avoid muscle atrophy and contracture deformity. 2, physical therapy: heat therapy, hydrotherapy, ultrasound, acupuncture, massage, traction, etc. 3.Pay attention to joint protection, reduce weight bearing, such as the use of knee pads in the knee joint, from sitting after standing up, should support the hands on the support or knee. 4.Activity or mobility support: use canes, crutches or walkers to assist with mobility or walking. 5.Orthopedic insoles or braces: According to the inversion or valgus deformity associated with osteoarthritis, use the corresponding orthopedic braces to balance the load on each joint surface. （If non-pharmacological treatment for osteoarthritis is ineffective, the following medications can be used respectively. (1) For patients with mild to moderate osteoarthritis, acetaminophen can be used. (2) In order to prevent the occurrence and development of osteoarthritis or delay the pathological process of osteoarthritis, joint cartilage protective drugs such as glucosamine hydrochloride or chondroitin sulfate can be taken. (3) For patients with moderate-to-severe osteoarthritis, selective COX-2 inhibitors (e.g., celebrex) or non-selective NSAIDs may be considered. (4) Other analgesics: such as tramadol, opioids, etc. 2.Local treatment Local use of various NSAIDs emulsions, creams, patches and Chinese ointment patches, etc. For severe symptoms, local closure treatment can be used. 3.Joint cavity injection Joint cavity injection of viscoelastic supplements, such as sodium hyaluronate, etc., once a week, generally 3-5 times a course of treatment, the joint fluid should be aspirated before injection, and the patient should reduce weight bearing for 48 hours after injection. (iii) Surgical treatment For those who have severe symptoms of osteoarthritis, non-surgical treatment is ineffective and progressive activity is limited, the following surgical treatment can be taken after examination by orthopedic surgeons 1. Arthroscopic surgery: such as flushing and cleaning, which is suitable for osteoarthritis with short symptoms, normal joint force line arrangement and moderate symptoms. 2.Osteotomy: Various orthopedic osteotomies to improve the balance of joint force lines are indicated for relatively young or obese individuals with osteoarthritis of the knee with internal or external knee deformity without severe lesions in the corresponding contralateral (medial or lateral) joint space. 3. Arthroplasty: For patients with persistent moderate-to-severe pain, limited mobility, X-ray confirmation of significant articular cartilage damage, and primary osteoarthritis generally older than 60 years of age. The advantages of arthroplasty are: relieving pain, preserving joint movement, maintaining joint stability, and basically equal length of the limb after surgery. In the past decade, artificial joint replacement has developed rapidly in China, and the indications for the treatment of serious hip and knee disorders have been gradually clarified, and the surgical technique has become increasingly mature. The use of artificial joint replacement for hip and knee osteoarthritis has been hailed as a “revolutionary advance in treatment”. Arthroplasty is a relatively mature orthopaedic surgery and is considered the most effective and successful procedure for the treatment of end-stage or severe arthritis.