1.What is femoral head necrosis? Blood flow to the femoral head is blocked or destroyed and causes bone ischemia in the head, which is called ischemic necrosis or aseptic necrosis of the femoral head. People who take hormones for a long time, drink alcohol, young children with acetabular dysplasia and hip trauma belong to the high-risk group. 2, what are the common clinical symptoms of femoral head necrosis? ① Pain is the most common symptom, intermittent episodes or continuous pain, and the pain is aggravated after activity, and in severe cases, pain occurs at rest. ② joint stiffness, decreased flexibility of activities, walking, running, squatting and other activities are significantly limited. Difficulty in flexion and extension of the affected hip joint, inability to stand for a long time, duck gait, etc. ③ Limping. Due to the unequal limbs, the patient has a limp. 3.What is the most common imaging test for femoral head necrosis? There are various cases of necrosis of the femoral head, including all necrosis, cone (wedge) necrosis, top hemimelia necrosis, focal necrosis, etc. CT or MRI also has an important diagnostic value. The correct diagnosis and staging directly determine the choice of treatment and efficacy. 4.What are the common clinical treatment methods? ①Conservative treatment: reasonable diet, low fat, appropriate high calcium and phosphorus intake; external traction and internal medicine; local massage, acupuncture, physiotherapy, fumigation and other Chinese medicine treatment methods; appropriate functional exercise. When the effect of conservative treatment is not obvious, timely surgery is needed to avoid the aggravation of the disease and delayed treatment. ②Surgery is the main treatment method for femoral head necrosis at present. Palliative surgery can be used in the early stage of the disease, such as: core decompression, bone grafting with blood vessels, vascular implantation, bone stenting and so on. In the late stage, most patients need to undergo artificial total hip or hemi hip arthroplasty to obtain a better quality of life.