At present, the causes of osteosarcoma are not yet clear, but it may be related to genetics, exposure to radioactive substances, and viral infections. It can also be secondary to other deformative osteitis and fibrous dysplasia of bone. Furthermore, some cases can also develop from other benign tumors, gradually degenerating into malignant tumors. Osteosarcoma commonly affects the long bones, mostly located at the metaphyseal ends, with fewer cases in the middle of the diaphysis. The tumor develops very rapidly, generally spreading gradually towards the ends of the bone, destroying the bone tissue, causing the tumor mass to quickly reach under the periosteum, and invading the neighboring muscle tissue outwardly.