Abstract: A polyaxial bone screw assembly includes a threaded shank body having an integral upper portion receivable in an integral receiver, the receiver having an upper channel for receiving a longitudinal connecting member and a lower cavity cooperating with a lower opening. A down-loadable compression insert having a sub-structure, a down-loadable friction fit split retaining ring having inner and outer tangs and an up-loadable shank upper portion cooperate to provide for pop- or snap-on assembly of the shank with the receiver either prior to or after implantation of the shank into a vertebra. The shank and receiver once assembled cannot be disassembled.

Abstract: A polyaxial bone screw assembly includes a threaded shank body having an integral upper portion receivable in an integral receiver, the receiver having an upper channel for receiving a longitudinal connecting member and a lower cavity cooperating with a lower opening. A down-loadable compression insert having a sub-structure, a down-loadable friction fit split retaining ring having inner and outer tangs and an up-loadable shank upper portion cooperate to provide for pop- or snap-on assembly of the shank with the receiver either prior to or after implantation of the shank into a vertebra. The shank and receiver once assembled cannot be disassembled.

Abstract: A cervical polyaxial bone anchor includes a longitudinal connecting member receiver structure and a cooperating shank. The shank has a body and an integral head with first and second spherical surfaces of different radii and a plurality of spaced curvate apertures for receiving portions of the longitudinal connecting member to result in a greater angle of inclination of the shank with respect to the receiver. The receiver has an upper channel and a lower cavity that further includes an expansion area and an operational seat for a split retainer ring that captures and fixes the shank head within the receiver.

Abstract: A polyaxial bone screw assembly includes a threaded shank body having an integral upper portion receivable in an integral receiver, the receiver having an upper channel for receiving a longitudinal connecting member and a lower cavity cooperating with a lower opening. The receiver can have crimp tabs, but is devoid of spring tabs and collet-like flexible structures. A down-loadable compression insert (some with lock and release feature), a down-loadable friction fit split retaining ring having super structure for temporary friction fit with an up-loadable shank upper portion cooperate to provide for pop- or snap-on assembly of the shank with the receiver either prior to or after implantation of the shank into a vertebra. The shank and receiver once assembled cannot be disassembled.

Abstract: An open implant closure mechanism includes a closure top with a square thread form in combination with a mating substantially similar thread form on a bone anchor having a load flank disposed at a reverse angle.

Abstract: A cervical polyaxial bone anchor includes a shank having an integral spherical head and a receiver having an upper channel for receiving a rod and a lower seat near a lower opening for receiving a closed retainer that includes a compressible upper portion engaged with the receiver seat and an expandable lower portion capturing the shank head. An outer sleeve slidable with the receiver prohibits expansion of the retainer lower portion during operation. A compression insert engages the retainer upper portion and is in friction fit with the shank head prior to fixing of an angle of the shank with respect to the receiver.

Abstract: Open implant closure structures include a helically wound guide and advancement flange form having splay control surfaces. Multi-start closures and closures with inner set screws have splay control contours for interlocking with cooperating flange forms of bone anchor receivers. Flange form heights, thicknesses and other geometry, such as splay control ramp angle may be varied.

Abstract: A polyaxial bone screw assembly includes a threaded shank body having an integral upper portion receivable in an integral receiver, the receiver having an upper channel for receiving a longitudinal connecting member and a lower cavity cooperating with a lower opening. The receiver can have crimp tabs, but is devoid of spring tabs and collet-like flexible structures. A down-loadable compression insert (some with lock and release feature), a down-loadable friction fit split retaining ring having super structure for temporary friction fit with an up-loadable shank upper portion cooperate to provide for pop- or snap-on assembly of the shank with the receiver either prior to or after implantation of the shank into a vertebra. The shank and receiver once assembled cannot be disassembled.

Abstract: An open implant closure structure includes a helically wound guide and advancement structure having at least two helically wound forms thereon providing a multi-start closing mechanism for use between spaced arms of a cooperating open medical implant having mating helically wound structure thereon. Illustrated structures include interlocking flange forms, v-threads, square threads, reverse angle threads and buttress threads and receivers with break-off extensions and cooperating tooling.

Abstract: A polyaxial bone screw assembly includes a threaded shank body and a receiver having an upper channel for receiving a longitudinal connecting member and a lower cavity. The longitudinal connecting member assembly includes a tensioned cord and has hard, non-elastic sleeves for attachment to the bone anchors, at least one spacer located between the bone anchors, and in some embodiments, an end elastic bumper and cord blocker. A down-loadable friction fit split retaining ring having inner and outer tangs and an up-loadable shank upper portion cooperate to provide for pop- or snap-on assembly of the shank with the receiver.

Abstract: Open implant closure structures include a helically wound guide and advancement flange form having splay control surfaces. Multi-start closures and closures with inner set screws have splay control contours for interlocking with cooperating flange forms of bone anchor receivers. Flange form heights, thicknesses and other geometry, such as splay control ramp angle may be varied.

Abstract: Open implant closure structures include a helically wound guide and advancement flange form having splay control surfaces. Multi-start closures and closures with inner set screws have splay control contours for interlocking with cooperating flange forms of bone anchor receivers. Flange form heights, thicknesses and other geometry, such as splay control ramp angle may be varied.

Abstract: An open implant closure structure includes a helically wound guide and advancement structure having at least two helically wound forms thereon providing a multi-start closing mechanism for use between spaced arms of a cooperating open medical implant having mating helically wound structure thereon. Illustrated structures include interlocking flange forms, v-threads, square threads, reverse angle threads and buttress threads and receivers with break-off extensions and cooperating tooling.

Abstract: A spinal bone screw has a receiver with upstanding arms forming a channel for receiving a longitudinal connecting member, such as a rod, the receiver being integral with a threaded shank. The receiver further includes inner surfaces in sliding engagement with an insert, the insert having a seating surface for the rod. The insert and rod being pivotable with respect to the bone screw in a single plane.

Abstract: A spinal bone screw has a receiver with upstanding arms forming a channel for receiving a longitudinal connecting member, such as a rod, the receiver being integral with a threaded shank. The receiver further includes inner surfaces in sliding engagement with an insert, the insert having a seating surface for the rod. The insert and rod being pivotable with respect to the bone screw in a single plane.

Abstract: A two-piece closure for polyaxial bone screws includes an outer fastener and an inner set screw, the outer fastener having a drive system with pockets that cooperate with a pronged drive tool. The polyaxial screw includes a lower pressure insert engaged with the outer fastener, the insert in some embodiments being made from a cobalt chrome alloy.

Abstract: Polyaxial bone screws include a receiver and a shank, the receiver having in inner concave surface defining a spherical void and the shank having an upper spherical portion, the shank upper portion and receiver concave surface being in moveable friction fit engagement prior to locking of the shank with respect to the receiver. The receiver includes a circular edge formed by a spheric section, the edge capturing the shank upper portion within the receiver. Bone screws may include pressure inserts, shank upper portions having separate retainer rings, receiver arms having break-off extensions, and one or two-piece closures.

Abstract: Open implant closure structures include a helically wound guide and advancement flange form having splay control surfaces. Multi-start closures and closures with inner set screws have splay control contours for interlocking with cooperating flange forms of bone anchor receivers. Flange form heights, thicknesses and other geometry, such as splay control ramp angle may be varied.

Abstract: Polyaxial and uni-planar bone screw assemblies include a multi-threaded shank body having an integral upper portion receivable in a one piece receiver, the receiver having an upper channel for receiving a longitudinal connecting member and a lower cavity cooperating with a lower opening. A compression insert and open retaining ring located in the receiver may be made of cobalt-chrome and the compression insert may provide a diametric interference fit with the receiver. Receivers or inserts may include resilient arm portions. The open ring cooperates with the shank to provide for pop- or snap-on assembly of the shank with the receiver either prior to or after implantation of the shank into a vertebra.

Abstract: Open implant closure structures include a helically wound guide and advancement flange form having splay control surfaces. Multi-start closures and closures with inner set screws have splay control contours for interlocking with cooperating flange forms of bone anchor receivers. Flange form heights, thicknesses and other geometry, such as splay control ramp angle may be varied.