An expandable medical framework for implantation in a mammalian body comprises a plurality of serpentine bands and connector columns. Each serpentine band comprises alternating straight band struts and turns. Each connector column comprises a plurality of connector struts and connects adjacent serpentine bands. The turns of a serpentine band comprise connected turns and unconnected turns, each connected turn having a connector strut extending therefrom. Each unconnected turn has no connector struts extending therefrom. The serpentine bands at the ends of the framework are each connected to an intermediate serpentine band via four or more connector struts which are equally spaced about the circumference of the expandable medical framework. Each two adjacent intermediate serpentine bands is connected one to the other via two connector struts which are equally spaced about the circumference of the expandable medical framework.