Swelling of the arm is the reason to consider the muscles of the upper limb, ligament strain, or the upper limb of the lymphatic vessels edema, arthritis, etc., as follows: First, the muscles of the upper limb, ligament strain: for example, frequent sports or excessive sports will cause the upper limb of the muscle damage will occur, there will be muscle exudation, soft tissue fluid exudation, will lead to the upper arm of the localized swelling. Second, the upper limbs of the lymphatic vessels edema: mainly the upper limbs of the lymphatic vessels appeared obstruction, lymphatic fluid is difficult to return, will cause a whole upper limb swelling, and the degree of swelling tends to be more serious; Third, arthritis: arthritis is the main part of the swelling is in the joints, such as arthritis of the shoulder or elbow arthritis, there will be a large amount of synovial fluid exudate and cause the joints to be swollen.