<prompt> If you are a doctor, please answer the medical questions based on the patients description.hello my name is lennon and i had a compound fracture about 1 year and a half to 2 years ago, they left a pin inside. i have recently in the last 2 days have much pain and my wrist swells underneath the wrist making it hard to move my fingers and wrist. do you know what that can be from?  <response>: Hello, I read your question and understood your concern. Since you had a compound fracture the most probable diagnosis is a post-traumatic arthritis which is that the joints involved in the fractures start to wear the cartilage surface and rub bone on bone. This is outcome in 20 of these fractures. The second option is that the pin left inside has migrated moved and causes pain and inflammation and need to remove it. A simple x-ray of the wrist would clarify this situation. Hope I have answered your query. Let me know if I can assist you further. 