Bone tumors are tumors that occur in the bones and their accessory tissue sites. While benign bone tumors are easily curable, malignant bone tumors develop rapidly and have poor prognosis. There are two types of malignant tumors: primary and secondary. Malignant tumors that metastasize from other tissues and organs in the body to the bone through blood circulation or lymphatic system are secondary malignant bone tumors. The main treatment for malignant bone tumors is surgical resection, and the most common method is amputation or joint severance. However, with the advancement of technology, the medical profession has started to carry out many effective attempts to preserve limbs through comprehensive treatments such as artificial prosthesis replacement, “extensive local excision combined with functional reconstruction” and adjuvant chemotherapy. Nowadays, it is no longer a dream for bone cancer patients to keep their legs. 1.Tumor resection and limb preservation surgery After patients are diagnosed with bone cancer, they should first undergo systemic high-dose combination chemotherapy, and then perform tumor resection and limb preservation surgery. The complete chemotherapy regimen is the most important part of the whole limb preservation treatment process. The multi-drug combination chemotherapy regimen can control the tumor cells in all stages, eliminate the tiny lesions of local and distant metastases, make the tumor decomposition obvious, reduce the tumor blood vessels and increase the necrosis, which is conducive to the removal of lesions in surgery, thus increasing the chance of limb preservation and reducing the metastasis and recurrence after surgery. Current clinical data show that proper surgical method combined with complete chemotherapy regimen, limb-preserving surgery for malignant bone tumors of the extremities improves the quality of survival of patients while not reducing the survival rate of patients. 2. Reconstruction of bone defects After bone resection for tumor segment, reconstruction of bone defects can be performed, and specific methods include artificial joint replacement, autologous or allogeneic bone transplantation, and reuse of tumor segment. Preventing and reducing complications can obtain satisfactory long-term results, which is very helpful to patients’ postoperative recovery. 3.What are the cases that can be done without amputation? (1) Tumors of the limbs and part of the spine with moderate degree of soft tissue invasion; (2) No invasion of the main neurovascular bundle, and the tumor can be resected with the best border. (3) No metastatic lesions, or metastatic lesions can be cured. (4) The overall condition of the patient is good, no signs of infection, and can actively cooperate with the treatment.