Devices for introduction into a body via a substantially straight conduit to form a predefined curved configuration, and methods employing such devices
View Patent ↗A device for introduction into a body in a straight configuration and assuming within the body a predefined curved configuration, includes an elongated element formed from a number of segments interconnected so as to form effective hinges therebetween. When the elongated element is confined to a straight state, the effective hinges transfer compressive forces from each segment to the next so that the elongated element can be pushed to advance it through a conduit. When the elongated element is not confined to a straight state, the effective hinges allow deflection of each segment relative to adjacent segments until abutment surfaces of the segments come into abutment, thereby defining a fully flexed state of the elongated element with a predefined curved configuration. The device can be produced with a wide range of two-dimensional and three-dimensional curved forms, and has both medical and non-medical applications.
1. A device for introduction into a body, the device comprising:
(a) a plurality of segments sequentially interconnected so as to form an effective hinge between adjacent of the segments; and
(b) a sequential deflection arrangement including a tensioning element linked to a terminal one of said segments,
wherein said segments, said effective hinges and said sequential deflection arrangement are configured such that:
(i) said plurality of segments initially assume a substantially straight state for introduction into the body, and
(ii) said sequential deflection arrangement causes sequential deflection of said segments about said effective hinges from the substantially straight state to a deflected state such that said plurality of segments cooperate to form a deflected shape within the body.
2. The device of claim 1 , wherein each of said segments is hollow.
3. The device of claim 1 , wherein each of said segments has a generally rectangular shape as viewed in cross-section perpendicular to a direction of elongation.
4. The device of claim 1 , wherein at least one of said segments has a generally isosceles trapezoid shape as viewed in cross-section perpendicular to an axis of rotation of said effective hinges.
5. The device of claim 1 , wherein said segments are separately formed segments interconnected at each of said effective hinges by a hinge pin.
6. The device of claim 1 , wherein the device is sized for deployment in an intervertebral space of the human spine.
7. The device of claim 1 , wherein said terminal segment is formed with a leading edge defined by at least one bevel surface to facilitate introduction into the body.
8. The device of claim 1 , wherein said sequential deflection arrangement further comprises a rigid element associated in sliding relation to said plurality of segments.
9. A method for performing spinal surgery comprising the steps of:
(a) providing a device comprising:
(i) a plurality of segments sequentially interconnected so as to form an effective hinge between adjacent of the segments, and
(ii) a tensioning element linked to a terminal one of said segments;
(b) with said plurality of segments deployed in a substantially straight state, introducing at least part of the device into an inter-vertebral space; and
(c) actuating said tensioning element to selectively induce sequential deflection of segments of said elongated element about said effective hinges from a straightened state to a deflected state such that said plurality of segments cooperate to form a deflected shape within the inter-vertebral space.
10. The method of claim 8 , wherein each of said segments is hollow.
11. The method of claim 8 , further comprising at least partially filling an internal volume within the deployed device with an osteo-inductive agent.
12. The method of claim 8 , wherein each of said segments has a generally rectangular shape as viewed in cross-section perpendicular to a direction of elongation.
13. The method of claim 8 , wherein at least one of said segments has a generally isosceles trapezoid shape as viewed in cross-section perpendicular to an axis of rotation of said effective hinges.
14. The method of claim 8 , wherein said segments are separately formed segments interconnected at each of said effective hinges by a hinge pin.
15. The method of claim 8 , wherein said terminal segment is formed with a leading edge defined by at least one bevel surface to facilitate introduction into the body.