Segmental tensioning of spinal tethers
View Patent ↗Implantable devices for dynamic interconnection between bones, and especially between vertebrae. The devices provide for various types of manipulation of a flexible connection such as a tether, such as by providing an aperture through which the flexible connection is passed and guided, or a post to which a loop of the flexible connection can be attached, or a groove in which a loop of the flexible connection can be placed.
1. A method for flexibly connecting vertebrae, comprising:
attaching a first tethering head to a first vertebra;
attaching a second tethering head to the first vertebra spaced apart from the first tethering head;
attaching a third tethering head to a second vertebra;
attaching a fourth tethering head to the second vertebra spaced apart from the third tethering head;
attaching a fifth tethering head to a third vertebra;
placing a first flexible member in a first groove in the first tethering head;
placing a second flexible member in a second groove in the second tethering head;
placing a third flexible member in a third groove in the third tethering head;
placing a fourth flexible member in a fourth groove in the fourth tethering head;
connecting the first vertebra to the second vertebra by tethering the first tethering head to the third tethering head with the first flexible member;
connecting the first vertebra to the second vertebra by tethering the second tethering head to the third tethering head with the second flexible member;
connecting the second vertebra to the third vertebra by tethering the third tethering head to the fifth tethering head with the third flexible member;
connecting the second vertebra to the third vertebra by tethering the fourth tethering head to the fifth tethering head with the fourth flexible member; and
leaving the first tethering head untethered from the fourth tethering head.
2. The method of claim 1 , further comprising:
attaching together free ends of the first flexible member and creating a first loop of flexible member before said tethering the first tethering head to the third tethering head with the first flexible member.
3. The method of claim 2 , further comprising:
leaving the second tethering head untethered from the fourth tethering head.
4. The method of claim 1 , further comprising:
attaching together free ends of the first flexible member and creating a first loop of flexible member before said placing the first flexible member in the first groove in the first tethering head.
5. The method of claim 4 , further comprising:
leaving the second tethering head untethered from the fourth tethering head.
6. The method of claim 1 , wherein the first flexible member is a loop.
7. The method of claim 6 , further comprising:
leaving the second tethering head untethered from the fourth tethering head.
8. The method of claim 1 , wherein the second flexible member is a loop.
9. The method of claim 8 , further comprising:
leaving the second tethering head untethered from the fourth tethering head.
10. The method of claim 1 , wherein said placing the first flexible member in the first groove comprises passing the first flexible member through an opening in a head of the first tethering head.
11. The method of claim 10 , further comprising:
leaving the second tethering head untethered from the fourth tethering head.
12. The method of claim 1 , further comprising:
leaving the second tethering head untethered from the fourth tethering head.