# US 11,076,889 B2 · Pivotable bone anchor assembly with pre-loaded multi-part retainer and pressure insert > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,076,889 B2 - Document ID: US11076889B2 - Status: Granted - Kind: B2 - Application number: 16/912,922 - Filed: 2020-06-26 - Published: 2020-10-15 - Granted: 2021-08-03 - Earliest claimed: 2004-11-23 - Applicants: Roger P. Jackson - Inventors: Roger P. Jackson - Web page: https://patentgrep.com/patent/US11076889B2 ## CPC - A61B 17/7035: {Screws or hooks, wherein a rod-clamping part and a bone-anchoring part can pivot relative to each other} - A61B 17/7032: {Screws or hooks with U-shaped head or back through which longitudinal rods pass} - A61B 17/7037: {wherein pivoting is blocked when the rod is clamped} - A61B 17/7011: {Longitudinal element being non-straight, e.g. curved, angled or branched (adjustable length longitudinal elements A61B17/7014; A61B17/7019 takes precedence, e.g. coil springs)} - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) ## Abstract A pivotal bone anchor assembly includes a receiver having an axial bore communicating with a bottom surface of the receiver through a bottom opening, and a bone anchor having an attachment portion configured for attachment to the bone of a patient and a capture portion opposite the attachment portion configured for uploading into the axial bore through the bottom opening. The assembly also includes a multi-part retainer comprising at least two separable retainer parts, with each retainer part being positionable within the axial bore prior to the capture portion. The retainer parts are configured to move at least partially away from each other during the uploading of the capture portion into the axial bore, and then to operably engage and pivotably secure the capture portion in spaced relation from an internal engagement surface of the axial bore with the bone anchor extending downwardly through the bottom opening. ## Claims ### Claim 1 A pivotal bone anchor assembly for securing an elongate rod to a bone of a patient via a closure, the pivotal bone anchor assembly comprising: a receiver comprising a vertical axis, an axial bore centered about the vertical axis, and a pair of upright arms having top surfaces and opposed interior surfaces defining an upwardly-open channel configured to receive the elongate rod, the axial bore communicating with a bottom surface of the receiver through a bottom opening and extending upward through the channel to the top surfaces of the upright arms, the axial bore including a discontinuous mating structure integrally formed therein adjacent the top surfaces of the upright arms and configured for mating with the closure, and an internal engagement surface adjacent the bottom opening; a bone anchor having an attachment portion configured for attachment to the bone and an integral capture portion opposite the attachment portion configured for uploading into the axial bore of the receiver through the bottom opening; a multi-part retainer comprising at least two separable retainer parts, each retainer part being positionable within the axial bore prior to the capture portion of the bone anchor and configured to operably engage the capture portion so as to pivotably secure the capture portion within the receiver with the bone anchor extending downwardly through the bottom opening; and a compression insert positionable within the axial bore and having an upper surface configured to engage the elongate rod, wherein the at least two retainer parts of the multi-part retainer are configured to move at least partially away from each other during the uploading of the capture portion into the axial bore, prior to pivotably securing the capture portion in spaced relation from the internal engagement surface, and wherein outer surfaces of the at least two retainer parts are configured for frictional engagement with the internal engagement surface upon an application of force onto the multi-part retainer, so as to lock an angular orientation of the bone anchor with respect to the receiver. ### Claim 2 (depends on 1) The pivotal bone anchor assembly of claim 1, wherein the bone anchor is configured for polyaxial pivotal motion with respect to the receiver upon the pivotal securement of the capture portion within the receiver, prior to locking the angular orientation of the bone anchor with respect to the receiver. ### Claim 3 (depends on 1) The pivotal bone anchor assembly of claim 1, wherein the outer surfaces of the at least two retainer parts are configured to slidably engage the internal engagement surface of the axial bore upon the pivotal securement of the capture portion within the receiver, prior to locking the angular orientation of the bone anchor with respect to the receiver. ### Claim 4 (depends on 1) The pivotal bone anchor assembly of claim 1, wherein the outer surfaces of the retainer parts are sized and shaped to match a contour of the internal engagement surface. ### Claim 5 (depends on 1) The pivotal bone anchor assembly of claim 1, wherein the internal engagement surface of the axial bore decreases in diameter toward the bottom opening. ### Claim 6 (depends on 5) The pivotal bone anchor assembly of claim 5, wherein each retainer part has a top surface, a bottom surface, and an outer surface that decreases in diameter in the direction from the top surface to the bottom surface. ### Claim 7 (depends on 1) The pivotal bone anchor assembly of claim 1, wherein the movement of the at least two retainer parts at least partially away from each other further comprises a pivoting of the retainer parts about adjacent upper edges. ### Claim 8 (depends on 1) The pivotal bone anchor assembly of claim 1, wherein each retainer part further comprises end walls in spaced parallel relation with the respective end walls of the at least one other retainer part when the multi-part retainer is in operable engagement with the capture portion within the axial bore. ### Claim 9 (depends on 1) The pivotal bone anchor assembly of claim 1, wherein the capture portion of the bone anchor further comprises an external spherical surface. ### Claim 10 (depends on 1) The pivotal bone anchor assembly of claim 1, wherein the compression insert further comprises outer side surfaces having laterally outward-facing grooves sized and shaped to cooperate with inwardly-protruding structures of the axial bore to restrict the motion of the compression insert relative to the receiver. ### Claim 11 (depends on 1) The pivotal bone anchor assembly of claim 1, wherein the upper surface of the compression insert further comprises an upwardly-curved saddle surface configured to receive an underside surface of the elongate rod. ### Claim 12 (depends on 1) The pivotal bone anchor assembly of claim 1, wherein the compression insert is operable to downwardly transfer the force to the multi-part retainer from the elongate rod to lock the angular orientation of the bone anchor with respect to the receiver. ### Claim 13 (depends on 1) The pivotal bone anchor assembly of claim 1, further comprising the closure, wherein the closure comprises a cylindrical body having an outer side surface with a continuous mating structure formed therein and complementary with the mating structure. ### Claim 14 (depends on 13) The pivotal bone anchor assembly of claim 13, wherein the cylindrical body of the closure includes a solid, closed off bottom surface configured to engage a top surface of the elongate rod. ### Claim 15 (depends on 13) The pivotal bone anchor assembly of claim 13, wherein the top surfaces of the upright arms of the receiver are configured to remain uncovered when the pivotal bone anchor assembly is locked with the closure. ### Claim 16 A pivotal bone anchor assembly for securing an elongate rod to a bone of a patient via a closure, the pivotal bone anchor assembly comprising: a receiver comprising a vertical axis, an axial bore centered about the vertical axis, and an upwardly-open channel formed into an upper portion and configured to receive the elongate rod, the axial bore communicating with a bottom surface of the receiver through a bottom opening and extending upward through the channel to a top surface of the receiver and including an internal engagement surface adjacent the bottom opening; a bone anchor having an attachment portion configured for attachment to the bone and an integral capture portion opposite the attachment portion configured for uploading into the axial bore of the receiver through the bottom opening; and a multi-part retainer comprising at least two separable retainer parts, each retainer part being positionable within the axial bore prior to the capture portion of the bone anchor and configured to operably engage the capture portion so as to pivotably secure the capture portion within the receiver with the bone anchor extending downwardly through the bottom opening, wherein the at least two retainer parts of the multi-part retainer are configured to move at least partially away from each other during the uploading of the capture portion into the axial bore, prior to pivotably securing the capture portion in spaced relation from the internal engagement surface, and wherein outer surfaces of the at least two retainer parts are configured for frictional engagement with the internal engagement surface upon an application of force onto the multi-part retainer, so as to lock an angular orientation of the bone anchor with respect to the receiver. ### Claim 17 (depends on 16) The pivotal bone anchor assembly of claim 16, wherein the bone anchor is configured for polyaxial pivotal motion with respect to the receiver upon the pivotal securement of the capture portion within the receiver, prior to locking the angular orientation of the bone anchor with respect to the receiver. ### Claim 18 (depends on 16) The pivotal bone anchor assembly of claim 16, wherein the outer surfaces of the at least two retainer parts are configured to slidably engage the internal engagement surface of the axial bore upon the pivotal securement of the capture portion within the receiver, prior to locking the angular orientation of the bone anchor with respect to the receiver. ### Claim 19 (depends on 16) The pivotal bone anchor assembly of claim 16, wherein the outer surfaces of the retainer parts are sized and shaped to match a contour of the internal engagement surface. ### Claim 20 (depends on 16) The pivotal bone anchor assembly of claim 16, wherein the internal engagement surface of the axial bore decreases in diameter toward the bottom opening. ### Claim 21 (depends on 20) The pivotal bone anchor assembly of claim 20, wherein each retainer part has a top surface, a bottom surface, and an outer surface that decreases in diameter in the direction from the top surface to the bottom surface. ### Claim 22 (depends on 16) The pivotal bone anchor assembly of claim 16, wherein the movement of the at least two retainer parts at least partially away from each other further comprises a pivoting of the retainer parts about adjacent upper edges. ### Claim 23 (depends on 16) The pivotal bone anchor assembly of claim 16, wherein each retainer part further comprises end walls in spaced parallel relation with the respective end walls of the at least one other retainer part when the multi-part retainer is in operable engagement with the capture portion within the axial bore. ### Claim 24 (depends on 16) The pivotal bone anchor assembly of claim 16, wherein the capture portion of the bone anchor further comprises an external spherical surface. ### Claim 25 (depends on 16) The pivotal bone anchor assembly of claim 16, further comprising a compression insert positionable within the axial bore and having an upper surface configured to engage the elongate rod, wherein the compression insert is operable to downwardly transfer the force to the multi-part retainer from the elongate rod to lock the angular orientation of the bone anchor with respect to the receiver. ### Claim 26 (depends on 25) The pivotal bone anchor assembly of claim 25, wherein the compression insert further comprises outer side surfaces having laterally outward-facing grooves sized and shaped to cooperate with inwardly-protruding structures of the axial bore to restrict the motion of the compression insert relative to the receiver. ### Claim 27 (depends on 25) The pivotal bone anchor assembly of claim 25, wherein the upper surface of the compression insert further comprises an upwardly-curved saddle surface configured to receive an underside surface of the elongate rod.