<s>[INST] I have two toes that have turned black under the nail bed, one on each foot. They have been this way for several months, with no pain. Yesterday, a third toe began turning black under the nail bed, and the toe itself is red, swollen, and painful. I have not been injured and my shoes are very comfortable. I have no other symptoms of anything. What could this be? [/INST] Hello,The sore and swollen toes can be related to a local fungal infection or a past injury in the area. This can also happen due to chill pains. A direct examination is needed to find the cause. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Praveen Tayal, Orthopedic Surgeon </s>