several weeks ago a laundry basket full of wet towels fell on my upper inside bicept. immediately a large lump the size of an orange formed on my arm but no visible bruising. It is very sore and hurts all the way up to my shoulder causing constant pain. i thought it would go away by now. what do you think it is?
Hi and welcome to Chat Doctor. Thank you for your query. Well, this is probably post-traumatic hematoma or fibrous and this should pass spontaneously in several weeks.  Also, considering your description this may be some other benign subcutaneous lesion such as lipoma, fibrous or atheroma and if there are no skin changes such as redness, pus discharge or pain and fever then you should not be worried since it can be easily surgically removed under local anesthesia. Then it there is doubts it can be sent to the patohistologic analysis. I hope I have answered you query. If you have any further questions you can contact us in every time. Kindly regards. Wish you a good health.