Conversation: The conversation between human and AI assistant.
[|Human|] I injured my knee 2 months ago when a board with a rusty nail hit it and punctured the skin. I believe the nail hit the bone as well. It swelled up for one day but after that it went down and was fine. Today, after 2 months, I just noticed that a small (big knuckle sized) lump has developed in the same location. What would cause this lump to appear after 2 months?
[|AI|]  Hi.based from your description, it could be a fibrous tissue formation on the previous site of injury. It is similar to scar formation, only coming from the inside. It is best if you consult with a doctor, preferably a general or an orthopedic surgeon, for clinical evaluation. Other tumor types must also be ruled-out. Diagnostics (such as imaging and tissue biopsy) and management (medical and/or surgical) will be directed accordingly. Hope this helps. Good day!!~ Chat Doctor.