Osteosarcoma is a very common malignant tumor, primarily occurring at the distal femur, proximal tibia, and proximal humerus. Its manifestations mainly include persistent pain at these three locations, which gradually worsens and is accompanied by nighttime pain. Secondly, there is local swelling; the surface of the tumor may feel warmer to the touch and may even exhibit prominent veins, leading to restricted joint movement near the tumor. Thirdly, some patients may exhibit signs of systemic deterioration, such as weight loss, anemia, and fatigue. Fourthly, osteolytic osteosarcomas often erode the bone cortex, eventually weakening the bone and leading to pathological fractures. Thus, the symptoms of osteosarcoma include persistent pain in specific areas accompanied by nighttime pain, local swelling, systemic deterioration, and pathological fractures in many patients.