Other

Jackson, Roger P.

Roger, Jackson P.

Surber, James L.

James L Surber

Roger P Jackson

Nathaniel D Ginzton

Nathaniel David Ginzton

Jurell D Baker

Jackson P Roger

A pivotal bone anchor assembly includes a bone anchor having a proximal capture portion and an anchor portion, and a receiver having a channel for receiving a rod, an internal cavity with upper expansion and lower locking regions, and a central bore with an inwardly-protruding circumferentially-extending interference engagement structure. The assembly also includes a pressure insert having an upper surface for engaging the rod and an exterior surface for engaging the interference engagement structure to restrict movement of the pressure insert within the central bore. After the proximal capture portion of the bone anchor is positioned within internal cavity, the pressure insert is downwardly movable within the central bore to force the exterior surface at least partially past the interference engagement structure to inhibit the pressure insert from moving back up within the central bore.

Pivotal bone anchor assembly with forcibly downwardly displaceable pressure insert

A method of assembling a pivotal bone anchor assembly includes loading an insert into a central bore of a receiver, with the receiver having the central bore extending upward from a bottom opening to and through a first channel for receiving a rod, and the insert having an upper portion defining a second channel, opposite lateral protrusions extending outwardly in a direction transverse to the second channel, a lower collet portion, and a center opening. The method also includes positioning the insert into the central bore with the opposite lateral protrusions located adjacent to and above interference abutment surfaces formed into the central bore, and positioning a load ring within the center opening of the insert. The method further includes uploading a shank head into the central bore of the receiver through the bottom opening, capturing the shank head within the lower collet portion of the insert, and then forcibly downward displacing the insert within the central bore with the tooling so as to move the opposite lateral protrusions below the interference abutment surfaces.

Method of assembling a pivotal bone anchor assembly with a downwardly displaceable collet insert

A pivotal bone anchor assembly includes a receiver having a first channel for receiving a rod and a central bore with a seating surface adjacent a bottom opening with a first cut-out portion. The assembly also includes a bone anchor having an upper end portion pivotably engageable with the seating surface, an anchor portion opposite the upper end portion, and a neck extending between the upper end and anchor portions. The assembly further includes an insert positionable in the central bore with a second channel alignable with the first channel, a concave lower surface engageable with the upper end portion of the bone anchor, and a second cut-out portion alignable with the first cut-out portion. The neck and at least a portion of the upper end portion of the bone anchor are positionable into the first cut-out portion and the second cut-out portion, respectively, to provide for increased pivotal angulation of the bone anchor with respect to the receiver in the direction of the cut-out portions.

Pivotal bone anchor assembly with increased shank head angulation

A pivotal bone screw assembly includes a threaded shank body having an integral upper portion receivable in a receiver, with the receiver having an upper channel for receiving a longitudinal connecting member and a lower cavity cooperating with a lower opening. The assembly also includes a downloadable compression insert with a side arm extension for engagement and compression by a vertically-translating insert side compressing member so as to lock the assembly independent of the closure top.

Pivotable bone anchor assembly with independent provisional locking by insert compressing member

A spinal fixation system includes a plurality of bone anchors, each having an anchor portion and a shank head with an upper spherical surface having a first diameter extending downward to an inner edge of an annular shelf spaced below a hemisphere plane, and a lower spherical surface having a second diameter greater than the first diameter extending downward from an outer edge of the annular shelf toward a neck extending between the shank head and anchor portion. The system also includes both pivoting and non-pivoting receiver sub-assemblies, with each receiver sub-assembly including a receiver having a central bore with a seating surface adjacent a bottom opening and a channel for receiving a rod. Each receiver sub-assembly also includes one of a multiplanar retaining structure, a monoplanar retaining structure, or a monoaxial retaining structure positioned therein and slidably engageable with the seating surface after capturing the shank head upon its uploading through the bottom opening.

Spinal fixation system with modular receiver sub-assemblies for connecting with bi-spherical universal shank heads

A pivotal bone anchor assembly includes a receiver having a cavity with a bottom opening and a first channel for receiving a rod, and a shank having a head positionable into the cavity with the shank extending downward through the bottom opening. The assembly also includes an insert positionable into the central bore above the shank head and having a second channel alignable with the first channel, opposite extensions extending outwardly in the direction of the channels to block rotation between the insert and the receiver, and upward-facing surfaces located laterally outward from and on each side of the second open channel. The upward-facing surfaces are configured for releasable compressive engagement by a compressing tool after the elongate rod is received within the channels and prior to a final locking of the assembly so as to provisionally lock the shank from pivoting with respect to the receiver.

Pivotal bone anchor assembly with independent provisional locking

A pivotal bone anchor assembly includes a receiver defining a central bore with a circumferentially-extending horizontal interference structure located above an upper expansion region and a lower locking region, and a shank having an upper end portion up-loadable into the central bore through a bottom opening. The assembly also includes a retainer having an upper portion and a lower expansion portion pre-positioned within the upper expansion region and being operable to capture the upper end portion of the shank, and a compression insert postionable within the central bore having an upwardly-facing surface for engaging a rod, an exterior side surface for engaging the horizontal interference structure, and a lower recess for receiving the upper portion of the retaining structure in a side-to-side overlapping engagement. The compression insert is restrained from moving downwardly within the central bore until forcible downward displacement by direct engagement with tooling to drive the exterior side surface of the compression insert at least partially through the horizontal interference structure.

Pivotal bone anchor assembly with retainer pre-positioned in expansion chamber and tool-deployable insert

A receiver assembly for securing an elongate rod to a bone anchor including a receiver and a threaded plug. The receiver including an upper portion defining a channel to receive the elongate rod, an interior surface having helically wound receiver thread, and an exterior surface having in some embodiments first and second horizontal curvate extending instrument engaging grooves. The threaded plug including a longitudinal axis, a lower surface having a protrusion, and an external side surface having a continuous helically wound closure thread to rotatably mate with the helically wound receiver thread. The continuous helically wound closure thread including a lower leading surface and an upper trailing surface, both in some embodiments extending perpendicular to the longitudinal axis, and a cylindrical outer crest surface extending parallel to the longitudinal axis. When the protrusion on the threaded plug engages the elongate rod, the threaded plug does not extend overtop a top surface of the receiver.

Medical implant thread plug having a lower rod engaging extension

A pivotal bone anchor assembly includes a pre-assembled receiver assembly and a bone anchor with a capture portion uploadable into the receiver assembly through a lower opening. The receiver assembly includes a receiver defining a channel for receiving a rod and an axial bore having a recess and a spherical seating surface above the lower opening. The receiver assembly also includes a retainer operable to capture the capture portion within the axial bore with the bone anchor extending downward through the lower opening, and a pressure insert having an upper surface operable to engage the elongate rod and a lower surface operable to engage the capture portion. The receiver assembly further includes a pair of opposed, semicircular-shaped shaped biasing members in overlapping engagement with the pressure insert and configured to bias the pressure insert against the capture portion to provide a pre-lock friction fit for the pivotal bone anchor assembly.

Pivotal bone anchor assembly with biasing members for pre-lock friction fit

A pivotal hone screw assembly includes a shank having a capture portion and an anchor portion, and a receiver assembly in a pre-assembled configuration that includes a receiver, a retainer, and a separate pressure insert. The receiver has a central bore with a lower chamber, with the retainer being pre-assembled and contained within a wider portion of the lower chamber prior to uploading the capture portion of the hone anchor through a bottom opening, and with the insert being pre-assembled into the receiver above the retainer. The pre-assembled insert and retainer have an overlapping engagement with each other prior to and during the uploading of the capture portion through the bottom opening, with the retainer configured to expand to receive the capture portion and then to close around and retain the capture portion within the lower chamber while providing for pivotal motion of the shank relative to the receiver.

Modular pivotal bone anchor assembly having pre-loaded insert engageable with restrained pre-loaded expandable retainer

A receiver assembly includes a receiver with a base defining a central bore for receiving the head of a bone anchor and upright arms defining a channel for receiving a rod, with the central bore having through apertures extending outwardly to outer side surfaces of the receiver and the upright arms having top surfaces, opposite front and back surfaces, vertical tool-engaging slots extending downward from the top surfaces to the through apertures for slidably receiving an insert compression tool, and horizontal tool-engaging grooves on either side of the vertical slots that extend laterally to a front or back surface of the upright arm. The assembly also includes an insert positionable within the central bore with an upward-facing outer engagement surface located within a through aperture and aligned with a vertical tool-engaging slot, and which is configured for compressive engagement by the insert compressing tool to independently lock a position of the receiver with respect to the bone anchor.

Receiver assembly having a vertical tool-engaging slot for independent lock via tooling

A medical implant assembly includes a shank having a head and an anchor portion, and a receiver having a central bore with a locking recess adjacent a bottom opening, an expansion recess above the locking recess, and a horizontal ridge extending circumferentially above the expansion recess. The assembly also includes an insert uploadable into a first position within the central bore with outer surfaces engageable with the horizontal ridge in a first position, a locking ring initially positionable within the lower locking recess or the upper expansion recess, and a blocking ring positionable within the central bore at least partially above the locking ring. The locking ring is first expanded within the expansion recess during uploading the shank head through the bottom opening, and then moves downward into the locking recess to capture the shank head within the central bore. The insert is downwardly displaceable by tooling to a second position with the insert engagement with the shank head, and with the blocking ring occupying the expansion recess to inhibit the locking ring from moving back up into the expansion recess.

Bottom loaded pivotal bone anchor assembly with locking and blocking rings and insert tool deployment

A bone anchor assembly includes a shank having a head and an anchor portion, and a receiver having a first channel to receive a rod and an axial bore with an upper internal thread, interference abutment surfaces below the upper internal thread, and a bottom opening. The assembly also includes an insert having a second channel to receive the rod and opposite lateral protrusions positioned above the interference abutment surfaces upon loading into a first position within the axial bore. The assembly further includes a resiliently expandable retainer positionable within the axial bore adjacent the bottom opening to capture and hold the head in the receiver. After the head is uploaded into the axial bore, the insert is downwardly deployable by tooling into a second position with the opposite lateral protrusions being forced below the interference abutment surfaces and with lower portions of the insert entering into compressive overlapping engagement with the retainer to hold down the retainer within the axial bore.

Bone anchor assembly having a tool deployable insert in compressive overlapping engagement with a retainer

A pivotal bone anchor system includes a plurality of bone anchors with rounded capture portions having a circumferentially extending outer engagement surface without flat side faces. The system also includes multi-planar receiver sub-assemblies, each comprising a multi-planar receiver defining a cavity with a multi-planar seating surface, and a multi-planar pivoting retainer configured for multi-planar motion upon engagement with both the multi-planar seating surface and the outer engagement surface of a bone anchor. The system further includes uni-planar receiver sub-assemblies, each comprising a uni-planar receiver defining a cavity with a uni-planar seating surface, and a uni-planar pivoting retainer configured for uni-planar motion upon engagement with the uni-planar seating surface and the outer engagement surface of another bone anchor. The capture portions of the bone anchors are configured for capture by either a multi-planar or uni-planar receiver sub-assembly without further modification or adjustment.

Pivotal bone anchor system with modular receiver sub-assemblies and universal bone anchors

A pivotal bone anchor assembly includes a shank having a shank head and an anchor portion, and a receiving member having an upper portion defining an open channel for receiving an elongate rod and a lower portion with a downwardly extending collet structure defining a lower portion of a central bore for receiving the shank head upon uploading through a lower collet opening. The assembly also includes a pressure insert positionable into the central bore prior to uploading the shank head, and an outer ring slidably engageable with an outer surface of the collet structure to inhibit the collet structure from expanding. After the shank head has been uploaded and captured within the central bore, the pressure insert is downwardly compressed against the shank head by the elongate rod so as to lock the position of the shank with respect to the receiving member.

Growing community of inventors

Kansas City, KS, United States of America

James L Surber