An endoluminal support structure or stent, comprising: a frame comprising a first opening, a second opening, and a longitudinal axis therebetween, and comprising a plurality of elongated strut members interlinked by a plurality of swivel joints , wherein the swivel joints comprise a rotation axis perpendicular to the longitudinal axis of the frame and cooperate with the strut members to adjustably define a shaped structure between a compressed orientation and an expanded orientation, wherein each swivel joint forms a scissor mechanism with a first strut member (11-1) and a second strut member (11-2), wherein the strut members are arranged as a serial chain of linked scissor mechanisms, wherein the last scissor mechanism is joined to the first scissor mechanism in the chain; and an actuation mechanism comprising a rod , a first support mount (35-3) configured to couple the rod to the frame at a first anchor point (15-3) and a second support mount (35-5) configured to couple the rod to the frame at a second anchor point (15-5); wherein the first support mount (35-3) comprises a first threaded mount, the rod comprises a first helical thread, and the first threaded mount is configured to cooperate with the first helical thread; wherein the actuation mechanism is configured such that rotation of the rod in a first direction urges the anchor points (15-3, 15-5) outwardly to actuate collapse of the frame to the compressed orientation, and rotation of the rod in a second direction opposite to the first direction urges the anchor points (15-3, 15-5) inwardly to actuate expansion of the frame to the expanded orientation; wherein the actuation mechanism is self-locking to maintain the frame at a desired diameter; and wherein the endoluminal support structure or stent is configured to be implanted into a biological lumen. a frame comprising a first opening, a second opening, and a longitudinal axis therebetween, and comprising a plurality of elongated strut members interlinked by a plurality of swivel joints , wherein the swivel joints comprise a rotation axis perpendicular to the longitudinal axis of the frame and cooperate with the strut members to adjustably define a shaped structure between a compressed orientation and an expanded orientation, wherein each swivel joint forms a scissor mechanism with a first strut member (11-1) and a second strut member (11-2), wherein the strut members are arranged as a serial chain of linked scissor mechanisms, wherein the last scissor mechanism is joined to the first scissor mechanism in the chain; and an actuation mechanism comprising a rod , a first support mount (35-3) configured to couple the rod to the frame at a first anchor point (15-3) and a second support mount (35-5) configured to couple the rod to the frame at a second anchor point (15-5); wherein the first support mount (35-3) comprises a first threaded mount, the rod comprises a first helical thread, and the first threaded mount is configured to cooperate with the first helical thread; wherein the actuation mechanism is configured such that rotation of the rod in a first direction urges the anchor points (15-3, 15-5) outwardly to actuate collapse of the frame to the compressed orientation, and rotation of the rod in a second direction opposite to the first direction urges the anchor points (15-3, 15-5) inwardly to actuate expansion of the frame to the expanded orientation; wherein the actuation mechanism is self-locking to maintain the frame at a desired diameter; and wherein the endoluminal support structure or stent is configured to be implanted into a biological lumen. <EOS>