Bone marrow edema of the knee joint of the right arm in a construction site injury dr examination is not a fracture, it is a reaction of the bone marrow to the injury. Bone marrow edema is not a fracture, it is a reaction of bone marrow to trauma, this kind of injury is mainly in the bone marrow but not in the bone, it belongs to the non-specific pathological phenomenon. Bone marrow edema is mainly caused by infection, bone trauma, etc. Aseptic inflammation occurs in the bone marrow, which indirectly leads to damage to the bone marrow due to damage to the bone mass, resulting in edema. Generally, non-steroidal anti-inflammatory drugs such as ibuprofen and physical therapy should be applied in a timely manner. After timely and effective treatment, most of the patients have a good prognosis, and the above drugs should be applied under the guidance of a doctor.