Hi - I ve recently noticed a dull pain in my left shoulder blade (or the crevice between the shoulder blade & spine). I guess it s been going on for maybe 5 or 6 months now. I don t notice it being constant, more sporadic, and it s not a sharp pain that takes my breath away, but more of an ache that requires readjusting my posture & possibly taking an ibuprofen. Over the past couple of days I ve noticed it more, but in the last 3 weeks I ve taken up an exercise routine that involves using the weight machines. I used to be an avid exerciser, and now after a couple of years I m trying to get back into it. I m worried about this pain due to things I ve seen online about left shoulder blade pain, particularly pancoast tumors . I m not a smoker (but my mom smoked when I was little), and I m in decent health as far as I know. I m a 31 yr old female, 5 4 & 170 lbs. Note: I can really notice the pain/ache when I m sitting in a chair & lean forward with my arms dangling on either side of my legs. Please let me know what you think!