<s>[INST] 2 days ago I noticed a nodule which seems subcutaneous on the palmar surface of my left index finder. It is just proximal to the proximal IP joint. It is about 4 mm in size, blue, and painful. I thought it might be a ganglion cyst, but the blue color, location pain and tenderness make me doubt that. Any thoughts? [/INST] Hello, Most probably it will be a ganglion. Other possibilities like arthritic nodule have to be ruled out. Consult an orthopedician and get evaluated. An MRI scan is required for further assessment. Hope I have answered your query. Let me know if I can assist you further. Regards, Dr. Shinas Hussain, General & Family Physician </s>