It is pointless to rely on chemotherapy alone without surgical removal to treat osteosarcoma. For osteosarcoma, surgery is ultimately needed to take out the tumor, and the patient can survive only when the tumor is removed cleanly. It can be said that surgical treatment of osteosarcoma is very important and essential. Is there a high rate of limb preservation in surgical treatment of osteosarcoma? Is the limb preservation rate related to the effect of chemotherapy? The limb preservation rate for osteosarcoma in our hospital and some major international hospitals is around 90%. The limb preservation rate is closely related to the growth site of the tumor, for example, whether the tumor grows in the limb or pelvis or spine, whether the tumor encircles important blood vessels and nerves, and whether there is sufficient soft tissue coverage after resection. The rate of limb preservation is also related to the effect of chemotherapy. The better the effect of chemotherapy, the higher the rate of limb preservation; if the effect of chemotherapy is poor and the edema band is getting heavier, the doctor may consider amputation in this case. Which patients cannot have limb preservation? 1.The tumor is surrounded by or passes through important blood vessels and nerves, and it is difficult to remove the whole tumor, so limb preservation cannot be performed at this time; 2.Lack of sufficient soft tissue coverage when bone reconstruction is carried out after tumor removal, at this time, limb preservation is risky; 3.The patient cannot tolerate chemotherapy or has poor response to chemotherapy, and the prognosis is considered high risk, so limb preservation treatment is not suitable at this time; 4.The presence of active infection is a contraindication for limb preservation surgery. In addition to the above-mentioned situations where limb preservation therapy is contraindicated, limb preservation is also contraindicated in cases where the patient is subjectively uncooperative or the family is uncooperative during the limb preservation process. What are the methods of limb preservation? Which limb preservation methods are commonly used in children? The common methods of limb preservation are: (1) tumor-based prosthesis replacement; (2) large allogeneic bone graft; and (3) autologous bone transfer including autologous bone molding. Among them, tumor-based prosthesis replacement is the most used and the most mature technology at present. However, it still has certain complications, such as the prosthesis cannot stay in the body for a lifetime, and it may cause secondary revision after a long time due to loosening and other problems. Allogeneic bone grafting technique is also a more commonly used surgical procedure, and the problem of non-healing of large sections of allogeneic bone that occurs with it still has no solution. Autologous bone transfer technique is a more popular surgical procedure in our hospital nowadays, however, its indications are very limited, the patient’s tumor must grow in the middle segment of the long bone, in addition, if this technique is performed both joint ends must retain sufficient bone volume. However, if the patient is eligible for the autologous bone relocation technique, it is expected to enable the patient to be reconstructed by autologous bone after tumor removal with excellent long-term results without problems such as loosening and infection. As for rotationplasty, it is more common in foreign countries, but not much used in China. Is it true that the younger the age, the worse the effect of limb preservation treatment? This is true. The younger the age, the thinner the bone marrow cavity, the thinner the marrow cavity, the thinner the medullary needle can not be inserted, which leads to a thin root stem, and the long thin root tibia will cause the prosthesis to fracture after a long time. Therefore, in younger patients, the doctor needs to consider whether there is a matching prosthesis and other issues. Also, the patient is younger and is in a growth spurt, while one leg is growing during the growth spurt and the other is a prosthesis that is not growing. This can cause unequal length of both lower limbs after a long time. In addition, due to the young age of the patient, there may be uncooperative functional exercise, joint stiffness and poor joint function after replacement. Therefore, the younger the patient is, the more difficult it is to preserve the limb and the limb preservation plan should be carefully considered. Limb preservation in distal femoral osteosarcoma – tumor prosthesis replacement proximal tibial tumor prosthesis removal at the time of photo real meaning of limb preservation —- bone removal technique in osteosarcoma patients. After successful surgery completely own leg can Lengthening prosthesis in patients with osteosarcoma Application of allogeneic structural bone grafting in patients with osteosarcoma for limb preservation.