What are the possible causes of lower rib cage protrusion? I am currently undergoing ultra sound, MRI, and blood work to determine the cause of jaundice. The ultrasound included liver, pancreas, gall bladder, spleen, kidneys and bladder with nothing significant indicated. The MRI results are not yet reported. I am just wondering if something else could be pressuring the liver and causing the jaundice. At some time in the recent months I have suspected that the lower part of my rib cage was protruding. I can t help wondering if there could be a connection.