Abnormal signal in the marrow cavity of the lower femur may be due to abnormal bone marrow proliferation or lesions in the marrow cavity of the lower femur. If the number of hematopoietic cells in the patient’s bone marrow is abnormal, it may lead to the development of acute myeloid leukemia, which will eventually lead to abnormal bone marrow proliferation and show abnormal signals. At the same time, the presence of lesions such as malignant lymphoma and myeloma may also lead to the appearance of abnormal signals. Generally speaking, depending on the sequence of the abnormal signals, the significance of the signals may be different. Therefore, it is important to consult with a doctor in time and undergo relevant examinations in order to clarify the cause of the disease. If you have abnormal signals in the lower femoral medullary cavity, you should go to the hospital in time to confirm the diagnosis, and under the guidance of the doctor, treatment should be carried out.