Injury to the testicle and swelling when touching it may be caused by localized damage, infection, testicular torsion and other factors. 1. Localized damage: when the testicle area is injured, there may be soft tissue fluid oozing and a small amount of bleeding, which will make the local swelling, and when you touch it with your hand, you will feel the local swelling, which may be accompanied by pain, subcutaneous bruising and other symptoms. 2. Infection factor: after the testicle is damaged locally, and the local skin is broken, without good care, it may lead to infection in the damaged area, and the aggravation of infection will lead to localized enlargement of testicle, which may be accompanied by itching, redness, and even pus outflow. 3. Testicular torsion: after the testicle is damaged, testicular torsion may be induced, which will also cause pain and swelling symptoms, and the pain is particularly severe, and untimely treatment will also lead to testicular ischemia and necrosis. After testicular injury, it is recommended to consult a doctor for examination to identify the specific cause, and then under the guidance of the doctor to carry out targeted treatment to avoid causing other complications.