The symptoms of soft tissue injury in the arm are as follows. 1. pain. Soft tissue injury, due to the formation of local inflammatory edema, and often accompanied by small nerve damage, resulting in inflammatory metabolites on the peripheral nerves around the stimulation, there is a significant sense of pain. After the injury, due to the rupture of small blood vessels, there is bruising and exudation, and with the gradual increase in bleeding, local swelling is formed, which also produces irritation to the surrounding tissues and pain. 2. Local swelling. Mainly due to inflammatory edema and local bleeding after the injury leads to a gradual increase in swelling, especially after the injury, if no timely brake rest, resulting in further aggravation of the local injury, resulting in swelling is also more obvious. 3, unfavorable activity. After the injury, in the activity will be stretched to the location of the injury, resulting in pain more obvious, so there are unfavorable activities.