Swollen lymph nodes in the elbow joint mostly refers to swollen lymph nodes on the trolley, and the common causes of swollen lymph nodes on the trolley lymph nodes are infection, tumor, cell proliferation and metabolic abnormality, reactive hyperplasia and so on. 1. Infection: because of acute and chronic inflammation caused by bacteria, viruses, etc., such as the infection around the elbow joint or localized infection of the upper limb, or infection in other parts of the body through the body’s lymphatic system through the lymph nodes on the scooter, lymphocyte reactive hyperplasia, which can cause enlargement of lymph nodes. 2. Malignant tumors: such as lymphoma, tumor cells pass through the wall of lymphatic vessels and transfer to the lymph nodes along with the flow of lymphatic fluid, and the lymphocytes reactive hyperplasia will cause lymph node enlargement. 3. Abnormal cell proliferation and metabolism: it can also cause abnormal proliferation of lymphocytes, causing lymph node enlargement. 4. Reactive hyperplasia: such as systemic lupus erythematosus and other inflammatory reactions caused by lymphocytes, histiocytes reactive hyperplasia. Lymph nodes on the bursa are on the inner side of the upper arm, 3~4cm above the medial epicondyle of the humerus, in the intermuscular groove of the biceps and triceps muscles. There are many reasons for the enlargement of the lymph nodes on the bursa and it may also be related to leukemia, tuberculosis, inflammation of the drainage area, etc. If the symptoms continue to be unrelieved, it is recommended to consult a doctor in time to clarify the cause and carry out targeted treatment.