The staging of femoral head necrosis is very important. The staging reflects the different progress of the lesion, different pathological changes, and the corresponding treatment modalities are different. For example, in the early stage of femoral head necrosis, when the necrosis has just formed, the pathological changes are not very serious and the shape of the femoral head is relatively good, only some bone changes have occurred inside the femoral head, so it is obviously not suitable to replace the entire femoral head, but can do some more conservative treatment, including some medication, physical therapy, more rest, avoid excessive weight bearing, etc., and can also choose some preservation of the femoral head Surgical treatment, such as drilling and decompression, bone grafting, and strengthening support, can also be chosen to preserve the femoral head. However, in the case of advanced osteonecrosis, the entire femoral head is deformed and the osteoarthritis is severe, with severe and persistent clinical pain. For those who have osteonecrosis between very mild and very severe, it is a challenging choice for both the patient and the doctor to choose whether to choose a more conservative approach or to choose joint surgery. For example, this patient is more than 60 years old, his lesion is not the most serious case, but also not very light, if you take a more conservative approach, do some more conservative surgery, although he may drag a period of time temporarily without joint replacement, but also may not be able to achieve very good results; if you choose artificial joints, may be faster to relieve pain, faster to restore the function of the affected limb, and, modern artificial joints In general, the survival rate for 20 years of use can reach 85% to 90%, so we would favor artificial joint replacement surgery for a patient in his 60s. On the contrary, if the patient is very young, for example, in his thirties, he may have to have two or three more surgeries in the future because the artificial joint has a certain life expectancy. Therefore, for young patients, we can choose some relatively conservative methods, including conservative surgery, which is called head preservation (preservation of the femoral head), if the condition allows, in the hope of giving these young or middle-aged people a chance to recover their femoral head. Of course, if the lesion is more serious, including imaging and clinical manifestations are more serious, and the patient has tried many methods, but still does not work, and obviously affects daily life and work, even if young, may have to choose artificial joint replacement surgery.