The inner side of the arm feels swollen and accompanied by pain, and there are several common causes.1, swelling and pain due to strain or injury of the inner muscles of the upper limb, commonly seen in the daily work of the heavier, that is, the upper limbs of the work of the heavier people. It can also be seen in the more physical exercise, strenuous activities in the injury, thus appearing local inflammatory infiltration, congestion, edema, resulting in swelling and pain. 2, can be seen in the humerus medial epicondylitis, also often known as golf elbow, but also corresponding to the production of tendon inflammation, tendon stopping point of the congestion, edema, and thus the radioactive emergence of the medial arm pain and swelling. 3, can be seen in the upper extremity bony Tumor, due to the compression of the tumor leads to local swelling and pain. 4, see cervical spondylosis, due to cervical spondylosis leads to ulnar nerve nerve root compression, so that the ulnar nerve innervated area of the inner arm of the swelling and pain.