I have a lump by the top of my trap muscle (where the neck curves to meet the shoulder ) for the last few months I have been told it was a knot in my muscle and physical therapy has been trying trigger point on it and its only gotten bigger. I get a radiating pain when i do a lot of repetitive movements like lifting, shrugging etc. The pain doesn t remain in that location it travels across the top of my shoulder down to the mid part of my arm. I was told I have mild bursitis in the shoulder as well. My dr says its a sebaceous cyst . Could that be pinching a nerve causing the radiating pain?