<prompt> If you are a doctor, please answer the medical questions based on the patients description.I have had knots to form over the last year in the krook of my elbows. They seem to be muscle related and become sore and achey after doing a repetitive or strenguous exercise with my arms. I wonder if they are related to donating plasma on and off for a few years. Another one has popped up the last few weeks and I haven t given plasma in this arm for almost a year.  <response>: Hi, DEar, thanks for your query to Chat Doctor. I studied your query in depth.1-In My opinion the sore lumps which popped up last few was, most probably are due to the -post-donation thrombophebitis with fibrosis tissue in it-.2-Still you should check up for the Drums disease-which are painful lipomas, which could be other possibility for such lumps, without any relation to the donation.3-Hope this would solve your query.4-Wellcome for any more questions on new or this subject also... Have A Good Day.!! 