Rod attachment assembly for occipital plate
View Patent ↗The present disclosure relates, according to some embodiments, to orthopedic implantable device technology, and more specifically to implantable devices for use in stabilizing the occipitocervical junction and the cervical spine. For example, the disclosure relates to embodiments of an implantable orthopedic assembly generally comprising an occipital plate and one or more repositionable clamping assemblies for securing a stabilizing rod at a nonzero distance from a plate surface. One or more rails may extend laterally from a plate to support a clamping assemblies.
1. An implantable orthopedic assembly comprising:
an occipital plate comprising a top surface and a bottom surface, the bottom surface of the occipital plate adapted for securing to an occiput;
at least one rail extending laterally from a proximal portion of the occipital plate, the at least one rail comprising a top surface and a bottom surface;
at least one repositionable rod attachment assembly adapted to enclose a portion of the at least one rail, the rod attachment assembly further adapted for securing a portion of a stabilizing rod at a distance from the at least one rail, the rod attachment assembly comprising:
a slide body comprising a rail aperture adapted to frictionally contact at least one surface of the at least one rail, the slide body further adapted for lateral repositioning between a first rail position and a second rail position;
a saddle body adapted for repositioning between a first rotational position and a second rotational position, the saddle body further adapted to receive the portion of the stabilizing rod;
a retention ring positioned on an outside circumference of a circumferential recess in the saddle body and on an inside circumference of the slide body, the retention ring adapted to secure the saddle body to the slide body; and
a pressure cap comprising a rod contacting surface at a first side and an outwardly extending flange at a second side distal to the first side, the pressure cap adapted to maintain alignment between the received stabilizing rod and the saddle body and transfer an immobilizing force from the received portion of the stabilizing rod to the top surface of the at least one rail, the immobilizing force immobilizing the rod attachment assembly at a fixed rail position and in a fixed rotational position; and
a loading component positioned between the pressure cap and the saddle body of the at least one repositionable rod attachment assembly, wherein the loading component is in contact with the outwardly extending flange of the pressure cap, the loading component adapted to exert a bias on the pressure cap against the at least one rail to stabilize the at least one repositionable rod attachment assembly at an adjustable rail position and in an adjustable body position.
2. An implantable orthopedic assembly according to claim 1 , wherein the occipital plate further comprises at least one groove scoring at least one of the top surface of the occipital plate or the bottom surface of the occipital plate, the at least one groove adapted to facilitate contouring of the occipital plate.
3. An implantable orthopedic assembly according to claim 2 , wherein the at least one groove comprises a first groove and a second groove, the second groove substantially orthogonal to the first groove.
4. An implantable orthopedic assembly according to claim 1 , wherein a plurality of apertures is variably distributed across the occipital plate, wherein the plurality of apertures penetrates both the top surface of the occipital plate and the bottom surface of the occipital plate, and wherein at least one of the plurality of apertures is adapted to receive at least one bone fastener, the at least one bone fastener adapted to secure the bottom surface of the occipital plate to the occiput.
5. An implantable orthopedic assembly according to claim 4 , wherein the at least one bone fastener comprises a bone screw.
6. An implantable orthopedic assembly according to claim 4 , wherein the plurality of apertures comprises a substantially circular first aperture centered about a first aperture center axis.
7. An implantable orthopedic assembly according to claim 6 , wherein the first aperture center axis is non-orthogonal to at least one of the top surface of the occipital plate and the bottom surface of the occipital plate.
8. An implantable orthopedic assembly according to claim 4 , wherein at least one of the plurality of apertures comprises a countersunk aperture.
9. An implantable orthopedic assembly according to claim 1 , the occipital plate further comprising at least one instrument interface adapted to facilitate manipulation of the occipital plate with an instrument.
10. An implantable orthopedic assembly according to claim 9 , wherein the occipital plate further comprises an edge surface connecting the top surface of the occipital plate and the bottom surface of the occipital plate, and wherein the at least one instrument interface comprises a notch in the edge surface of the occipital plate.
11. An implantable orthopedic assembly according to claim 1 , wherein the occipital plate has a longitudinal axis parallel to the plane of the occipital plate and defining a first side of the occipital plate and a second side of the occipital plate.
12. An implantable orthopedic assembly according to claim 11 , wherein at least one rail comprises a first rail and a second rail, the first rail extending from the first side of the occipital plate, the second rail extending from the second side of the occipital plate.
13. An implantable orthopedic assembly according to claim 1 , wherein the slide body of the at least one repositionable rod attachment assembly is adapted for infinite lateral repositioning between the first rail position and the second rail position.
14. An implantable orthopedic assembly according to claim 1 , wherein the saddle body of the at least one repositionable rod attachment assembly is adapted for infinite rotational repositioning between the first body position and the second body position.
15. An implantable orthopedic assembly according to claim 1 , wherein the slide body comprises a slot that is adapted to at least partially enclose a portion of the at least one rail.
16. An implantable orthopedic assembly according to claim 1 , wherein the loading component comprises a wave spring.
17. An implantable orthopedic assembly according to claim 1 , wherein the pressure cap comprises a groove at one end adapted to contact the received portion of the stabilizing rod.
18. An implantable orthopedic assembly according to claim 1 , further comprising a retaining element that is adapted to be attached to the rail and prevent the slide body from sliding off an end of the rail.
19. An implantable orthopedic assembly according to claim 1 , wherein the inside circumference of the slide body is the inside circumference of a circumferential recess in the slide body.