In daily life, many patients with osteonecrosis of the femoral head have experienced “misdiagnosis” and “missed diagnosis” of bad luck. What exactly is the reason why femoral head necrosis is so easy to miss and misdiagnose? Sometimes patients have pain not in the hip, but in the surrounding joints, such as the knee, lumbosacral. Patients cannot accurately describe the main location of the pain during consultation, so it is not easy for clinicians to analyze the condition and conduct reasonable auxiliary examinations, thus easily misdiagnosed as other diseases such as lumbar disc herniation or osteoarthrosis of the knee. 2. Clinicians have insufficient knowledge of the disease and cannot understand the incidence of femoral head necrosis in recent years, so clinicians are prone to consider other diseases in the diagnosis and treatment process, while neglecting the analysis of the femoral head disease. 3. The analysis of femoral head disease. 3. Clinicians are not careful about the patient’s history inquiry and physical examination, and rely too much on CT and MRI examinations. It is not possible to determine the site of the disease through a comprehensive analysis of history analysis, clinical positive signs and auxiliary examinations.4. Femoral head necrosis can be accompanied by other orthopedic diseases, such as lumbar intervertebral disc herniation, osteoarthritis, rheumatoid arthritis, ankylosing spondylitis, etc. The symptomatic manifestations of these diseases can be confused with the symptoms of femoral head necrosis, and clinicians are prone to meet the diagnosis and treatment of the primary disease, while neglecting the The clinicians tend to satisfy the diagnosis and treatment of the primary disease, but neglect the diagnosis and treatment of the complications and secondary diseases. For example, ankylosing spondylitis and rheumatoid arthritis can involve the hip joint and cause osteonecrosis of the femoral head; after osteonecrosis of the femoral head occurs, the walking is swaying from side to side, causing uneven force on large joints such as the human lumbar spine and knee joint, which can be complicated by lumbar disc herniation and osteoarthrosis of the knee joint.