Spinal Arthroplasty Device and Method
An artificial spinal joint and methods for replacing at least a portion of a natural intervertebral disc are provided. In some embodiments, at least portions of facet joints are replaced along with the intervertebral disc.
1 - 79 . (canceled)
80 . A system for implantation in an intervertebral space defined between first and second vertebrae to permit movement of the first vertebra relative to the second vertebra, the system comprising:
a first arthroplasty section including a first upper contact portion sized to engage an endplate of the first vertebra, a first lower contact portion sized to engage an endplate of the second vertebra, an outer boundary with a first mating portion, and a first pair of articulation surfaces sized and shaped for slidable engagement; and
a second arthroplasty section including a second upper contact portion sized to engage an endplate of the first vertebra, a second lower contact portion sized to engage an endplate of the second vertebra, an outer boundary with a second mating portion, and a second pair of articulation surfaces sized and shaped for slidable engagement;
wherein the first mating portion is shaped to receive the second mating portion to connect the first and second arthroplasty sections within the intervertebral space.
81 . The system of claim 80 wherein the second mating portion includes a protrusion.
82 . The system of claim 81 wherein the protrusion is integrally formed with the second lower contact portion.
83 . The system of claim 81 wherein the protrusion is integrally formed with the second upper contact portion.
84 . The system of claim 80 wherein the outer boundaries of the first and second arthroplasty sections are in direct contact when the second mating portion is received within the first mating portion.
85 . The system of claim 80 wherein the first and second mating portions are sized to connect along an anterior-posterior midline axis extending through the intervertebral space.
86 . The system of claim 85 wherein the first pair of articulation surfaces are sized and shaped for slidable engagement on an opposite side of the anterior-posterior midline axis from the second pair of articulation surfaces.
87 . The system of claim 80 further comprising a fixation portion sized to extend posteriorly outside of the intervertebral space to receive at least one fastener.
88 . The system of claim 87 wherein the at least one fastener is a threaded bone fastener.
89 . The system of claim 88 wherein a tension band is attached to the at least one fastener.
90 . A system for placement in an intervertebral disc space between two vertebrae, the system comprising a pair of arthroplasty devices, each arthroplasty device including an upper portion slidably engaged with a lower portion and a mating portion shaped to interlock with the other arthroplasty device at an anterior-posterior midline through the intervertebral disc space, to resist migration of the arthroplasty devices with respect to each other.
91 . The system of claim 90 wherein the mating portions are formed along outer boundaries of the lower portions of each arthroplasty device.
92 . The system of claim 91 wherein the mating portions are formed along outer boundaries of the upper portions of each arthroplasty device.
93 . The system of claim 90 wherein one of the mating portions has a projection and the other mating portion has a U-shaped formation sized to interlock with the projection.
94 . A method of implanting a spinal arthroplasty system comprising:
accessing an intervertebral disc space through a posterior incision;
inserting a first arthroplasty portion into an area of the intervertebral disc space to one lateral side of an anterior-posterior midline axis defined through the intervertebral disc space, wherein the first arthroplasty portion includes a mating pair of slidable surfaces;
inserting a second arthroplasty portion into an area of the intervertebral disc space to the other lateral side of the anterior-posterior midline axis, wherein the second arthroplasty portion includes a mating pair of slidable surfaces; and
connecting the first arthroplasty portion to the second arthroplasty portion within the intervertebral disc space.
95 . The method of claim 94 wherein the step of connecting includes inserting a projection of the first arthroplasty portion into a mating recess of the second arthroplasty portion.
96 . The method of claim 95 wherein the projection is formed in an outer boundary of the first arthroplasty portion.
97 . The method of claim 94 wherein the first and second arthroplasty portions each include a lower portion comprising a bone engagement surface and one of the pair of slidable surfaces and wherein the step of connecting includes connecting the lower portions of the arthroplasty portions.
98 . The method of claim 94 wherein the arthroplasty portions are connected at the anterior-posterior midline axis.
99 . The method of claim 94 wherein the intervertebral disc space has an anterior area and a posterior area and the step of connecting includes interlocking the first and second arthroplasty portions in the anterior area of the intervertebral disc space.