Patient: My relative’s child, 18 years old, had a blow injury to his right thigh in August 2007. Six months later, he started to have pain in his right thigh. Later, the hospital confirmed the diagnosis of osteosarcoma in front of the femoral head. They suspect that it was caused by that traumatic stimulus. Do you think there is a theoretical and clinical possibility? Doctor: There is no report of post-traumatic osteosarcoma in the medical literature, but the possibility of osteosarcoma caused by trauma cannot be completely excluded. There is no evidence in the medical community to prove the direct causal relationship between trauma and osteosarcoma, and there are no similar reports in our clinical work in the hospital. Therefore, I believe that trauma or bone injury does not directly cause the development of osteosarcoma. Trauma is a kind of irritation, which theoretically can be one of the causes of tumor induction, but this association is not obvious in actual clinical work, and the medical conclusive conclusion cannot be based on a single case. However, on the other hand, trauma can cause either because the tumor is found on post-trauma radiographs or because the tumor can develop rapidly and thus be detected because of post-trauma tissue damage.