Please choose the correct ending to complete the given sentence: Health: [header] How to diagnose a broken thumb [title] Note any severe pain in the your thumb. [step] It is normal to experience severe pain right after you break your thumb. The pain happens because your bones have nerves surrounding them.

Ending1: They vibrate the top of your thumb in an attempt to detect the damage you have caused. [substeps] You may be able to identify the problem by feeling it. Ending2: When a bone breaks, it can irritate or compress the surrounding nerves, which causes pain. If you don't experience severe pain right after the injury, there is a chance that your thumb is not broken. Ending3: The pain can begin in your left hand and radiate outward into the right one or vice versa. Because of this pain, hold your hands in a closed position for a few minutes to help reduce the pain. Ending4: These nerves give you an electric shock, causing pain. When you break your thumb, the nerve is forced to go into the bone, resulting in pain.

Answer format: ending1/ending2/ending3/ending4