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. Limb Preservation Surgery After a patient is diagnosed with bone cancer, he or she should first undergo systemic high-dose combination chemotherapy, and then undergo limb preservation surgery by tumor resection. 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 at all stages, eliminate the microscopic 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 during surgery, thus increasing the chance of limb preservation and also reducing the metastasis and recurrence after surgery. Current clinical data show that proper surgical approach combined with a complete chemotherapy regimen, limb-preserving surgery for malignant bone tumors of the extremities improves the quality of patient survival while not decreasing the survival rate of patients. Reconstruction of bone defects After bone resection for tumor segments, reconstruction of bone defects can be performed, including artificial joint replacement, autologous or allogeneic bone grafting, and reuse of tumor segments. Prevention and reduction of complications can achieve satisfactory long-term results and are very helpful for patients’ postoperative recovery. In which cases can amputation not be done? Patients with the following four conditions can be considered for the surgical option of limb preservation without amputation: 1. Tumors of the limbs and part of the spinal bones with moderate degree of invasion within the soft tissues; 2. The main neurovascular bundle is not invaded and the tumor can obtain the best border resection. 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.