An expandable tissue supporting device of the present invention employs
ductile hinges at selected points in the expandable device. When
expansion forces are applied to the device as a whole, the ductile hinges
concentrate expansion stresses and strains in-small well defined areas.
The expandable medical device including ductile hinges provides the
advantages of low expansion force requirements, relatively thick walls
which are radio-opaque, improved crimping properties, high crush
strength, reduced elastic recoil after implantation, and control of
strain to a desired level. The expandable tissue supporting device
includes a plurality of elongated beams arranged in a cylindrical device
and connected together by a plurality of ductile hinges. Although many
ductile hinge configurations are possible, the ductile hinges preferably
have a substantially constant hinge cross sectional area which is smaller
than a beam cross sectional area such that as the device is expanded from
a first diameter to a second diameter, the ductile hinges experience
plastic deformation while the beams are not plastically deformed.