Cord for vertebral fixation having multiple stiffness phases

摘要

A dynamic stabilization system for stabilizing a vertebral segment of a spine. The system includes a first vertebral anchor, a second vertebral anchor and a cord. The system may also include a spacer positioned between the first and second vertebral anchor through which the cord extends. The first vertebral anchor is configured to be secured to a first vertebra and the second vertebral anchor is configured to be secured to a second vertebra. The cord is extendable from the first vertebral anchor to the second vertebral anchor. The cord has a variable stiffness through a range of displacement, wherein the stiffness of the cord increases as an applied tensile force on the cord is increased.

主权项

1. A dynamic stabilization system for stabilizing a vertebral segment of a spine, the system comprising:
a first vertebral anchor configured to be secured to a first vertebra; a second vertebral anchor configured to be secured to a second vertebra; a cord extendable from the first vertebral anchor to the second vertebral anchor, the cord having a variable stiffness through a range of displacement; and a spacer surrounding a portion of the cord; wherein: the stiffness of the cord increases as an applied tensile force on the cord is increased; the cord has a first phase of stiffness through a first range of displacement, a second phase of stiffness through a second range of displacement, and a third phase of stiffness through a third range of displacement; and the stiffness in the cord in the first phase is less than the stiffness in the cord in the third phase, and the stiffness of the cord in the second phase progressively increases from the stiffness in the cord in the first phase to the stiffness in the cord in the third phase.