Girl has steel bar behind sternum to reshape her sunken chest With the fix, Mackenzie Kurko is breathing easier. “Hey Mackenzie, how are you doing?” asked Dr. Steve Rothenberg during a recent checkup. She told him she has no pain when she lifts her arms and no trouble breathing. Her mother, Jessica Ketterhagen, says she is pretty much 100%. Just 3 months ago, Mackenzie was in Rocky Mountain Hospital for Children (RMHC) for surgery to fix what’s called pectus excavatum, funnel chest. Some ribs and her sternum grew abnormally. Mackenzie told CBS4 Health Specialist Kathy Walsh her chest was so sunken her mother used to say,” You could fit a whole tennis ball in there.”