I decided to do my project on concave chests. The medical term is Pectus Excavatum. It happens as a result of the sternum being sunk into the body. I created a 3D version of what a rib cage would like if the sternum was sunk in. normally the sternum appears flat which creates a oval-ish shape with the ribs (view of cross section). When the sternum is sunk in it creates a pumpkin shape. Depending on the person Pectus Excavatum can have an effect on the lungs functions.