Erosive bone destruction is defined as a malignant bone tumor with no definite boundary of destruction, no sclerotic ring envelope, and gradual migration between the tumor and normal bone. Erosive bone destruction is caused by malignant bone tumors and also seen in bone infections. Diagnosis of erosive bone destruction: 1. Systemic reaction: Patients with acute inflammation often have elevated body temperature and increased white blood cell count, while patients with benign bone tumors have normal body temperature and normal blood picture. Patients with certain malignant bone tumors such as undifferentiated reticulocytic sarcoma or rapidly growing malignant tumors also show elevated body temperature and increased white blood cell counts. The blood sedimentation of patients with acute and chronic inflammation and bone tuberculosis is mostly increased, while that of patients with benign bone tumors is mostly normal and that of patients with malignant bone tumors is often increased. 2.Process of development: Inflammation gradually subsides after developing to a certain extent or after anti-inflammatory treatment, some benign bone tumors can stop developing after developing to a certain extent, while malignant bone tumors continue to develop and destroy, and those who stop or disappear by themselves are extremely rare. 3.Local palpation: Inflammation often produces abscess, which is generally soft and fluctuates obviously. Bone tumors are generally harder or tougher, with solid feeling when touched and clear borders, and their tomb bases are mostly adhered to bone and cannot be moved. However, certain malignant tumors with rich blood vessels or bleeding may also have fluctuating sensation. 4.Puncture: abscess puncture can aspirate pus, and pus culture or smear staining can sometimes detect septic bacteria. Tumor puncture can only aspirate blood, and tumor tissue fragments can sometimes be aspirated by thick needle puncture.