There are many causes of swollen lymph nodes in the femur, which are usually caused by inflammation and tumor, etc. 1. Inflammatory reaction: Mostly abnormal enlargement of lymph nodes, usually related to inflammatory reaction of nearby tissues. For example, bacterial or viral infections can lead to infections in the lower limbs, buttocks, and perineum. Inflammatory factors will travel up the lymphatic vessels and stimulate the enlarged lymph nodes in the femoral region, resulting in enlarged lymph nodes. These enlarged lymph nodes often have obvious tenderness, soft texture and good mobility. 2. Tumor: malignant tumors in the lower limbs, pelvis and abdominal cavity, such as bone cancer, intestinal cancer, ovarian cancer, cervical cancer and other malignant tumors, can be metastasized through lymphatic transfer, resulting in enlarged lymph nodes in the femoral region; lymphoma, lymphoblastic leukemia can also invade lymph nodes in the femoral region, resulting in enlargement. These causes of lymph node enlargement, often hard texture, no tenderness, poor mobility. In addition, some connective tissue diseases, such as systemic lupus erythematosus and tuberculosis, can also lead to enlarged lymph nodes in the femur. Therefore, if you find enlarged lymph nodes in the femur, you should consult the doctor in time, complete the examination, make a clear diagnosis, and then follow the doctor’s instructions to be treated accordingly.