Patent ID: 7695427

Claim:
A prosthetic device for implantation around a body tissue structure in a patient in order to resiliently apply radially inwardly directed forces to the body tissue structure only when the body tissue structure has a circumferential size that is greater than a predetermined non-zero circumferential size comprising: a plurality of magnetic bodies arranged in a series so that each magnetic body is magnetically attracted to the next adjacent magnetic bodies in the series; and a plurality of link members, each link member extending from a respective one of the magnetic bodies into an interior of a next adjacent magnetic body in the series along an axis of magnetic attraction between the magnetic bodies between which that link member extends, each link member being movable by a limited amount into and out of the interior of the magnetic body into which that link member extends, such movement being parallel to the axis along which that link member extends, and each link member having a stop in the interior of the magnetic body into which that link member extends for cooperating with that magnetic body to stop, at a predetermined point, movement of that link member outward from that magnetic body, wherein each of the link members extends into the interior of the next adjacent magnetic body through an aperture in an exterior surface of that magnetic body, wherein the stop of that link member is larger than that aperture, wherein the interior of each magnetic body defines an open space that is larger than (1) the link member extending into that interior and (2) the stop of that link member when the open space, the link member, and the stop are measured perpendicular to the axis along which the link member extends, and wherein the aperture is larger than the link member extending through that aperture but smaller than the stop of that link member when the aperture, the link member, and the stop are measured perpendicular to the axis along which the link member extends.