Anchors for vertebral body
Implantable devices for dynamic interconnection between bones, and especially between vertebrae. Some devices include tethering heads that are independent of the bone connecting member (fastener, plate, hook, loop). 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 connector for coupling at least one of a first flexible tether and a second flexible tether to a bone, the connector comprising:
a bone connecting member extending along a longitudinal axis, the bone connecting member adapted and configured for connection with the bone;
a tethering head attached to said bone connecting member, said tethering head including first top surface extending across said tethering head, said tethering head including a through passageway extending through said tethering head, said through passageway being adapted and configured to accept therein the first flexible tether, said through passageway having an entrance, said through passageway having an exit, said through passageway having a generally V-cross-sectionally-shaped portion, said tethering head including a slot extending across said first top surface of said tethering head through said entrance of said through passageway and through said exit of said through passageway, said slot being adapted and configured and extending from said generally V-cross-sectionally-shaped portion of said through passageway to provide the first flexible tether with through access to said generally V-cross-sectionally-shaped portion of said through passageway, said tethering head having internal threads;
a threaded member adapted and configured to be threadably received within the internal threads; and
wherein said slot, at said entrance or exit, defines a first maximum width in a first direction substantially perpendicular to the longitudinal axis,
said generally V-cross sectionally shaped portion, at said entrance or exit, defines a second maximum width in a second direction substantially perpendicular to the longitudinal axis,
said second maximum width being greater than said first maximum width.
2. The connector of claim 1 , wherein said generally V-cross-sectionally-shaped portion of said through passageway includes a first passageway portion extending through said tethering head and further includes a second passageway portion extending through said tethering head, wherein said first passageway portion is adapted and configured to accept therein the first flexible tether, and wherein said second passageway portion is adapted and configured to accept therein the second flexible tether.
3. The connector of claim 2 , wherein said tethering head includes a ridge separating said first passageway portion and said second passageway portion.
4. The connector of claim 3 , wherein said generally V-cross-sectionally-shaped portion of said through passageway includes an apex portion, and wherein said apex portion aligns with said slot.
5. The connector of claim 2 , wherein said first passageway portion and second passageway portion are parallel.
6. The connector of claim 5 , wherein said tethering head includes a ridge separating said first passageway portion and said second passageway portion.
7. The connector of claim 6 , wherein said generally V-cross-sectionally-shaped portion of said through passageway includes an apex portion, and wherein said apex portion aligns with said slot.
8. The connector of claim 1 , wherein the said threaded member is a set screw.
9. The connector of claim 1 , wherein said threaded member includes a second top surface, and wherein said tethering head and said threaded member are adapted and configured to cooperate to allow said second top surface to be positioned at least one of at and below said first top surface when said threaded member is threadably received within said internal threads.
10. The connector of claim 1 , wherein said tethering head has a substantially flat side adapted and configured for resting on the bone when said bone connecting member is fully inserted into the bone.
11. The connector of claim 1 , wherein said threads have an outer diameter, and wherein said tethering head has a maximum width greater than said outer diameter of said threads.
12. The connector of claim 1 , wherein said tethering head and said threaded member are adapted and configured to cooperate to block said through access to said generally V-cross-sectionally-shaped portion of said through passageway when said threaded member is threadably received within said internal threads.
13. The connector of claim 1 , wherein said internal threads are within said through passageway.