Discomfort In The Serratus Anterior Area Turning Into Twitching. Protruding, Bulge In The Ribs. Cause?

Hi, my name is Lindsay and I have a question. I am in school for PT and having been working on my dad s back. All of a sudden (he said it came out of no where) he is having discomfort in the serratus anterior area on the right side that turns in to a twitching at night when he is on the couch that is persistent. When I was feeling the muscles, I noticed that the 9th rib specifically is protruding out with the ribs 10 and 11 also slightly bulging, lateral, almost in line with the superior angle of the scapula , roughly 6 inches below. Its is probably 3/4 of an inch out more than the other ribs and my dad said there is no pain in the area and he doesn t feel any rib discomfort but just the lower trap area and the serratus anterior is causing him pain. Years ago he broke the right clavicle and he has chronic headaches and back pain , specifically the low back. Any idea what is causing the rib bulge and the muscle pain? Please help!