A pivotal bone anchor assembly includes a shank having a shank head with a partial spherical shape at a proximal end and an anchor portion opposite the shank head for fixation to the bone of a patient. The assembly also includes a receiver having an upper portion defining a channel for receiving an elongate rod and a base defining a cavity in communication with the channel and with a bottom surface of the receiver through a distal opening. The assembly further includes a retainer positionable into non-rotatable and non-pivotal engagement with an inner surface of the cavity prior to the shank head being received within the cavity, with the retainer having a central opening configured to receive and capture the shank head within the cavity while allowing for pivotal motion between the shank and the receiver in at least one plane, and with a lower portion of the retainer extending below the bottom surface of the receiver.

A coupling device for coupling a rod to a bone anchor includes a receiving part configured to receive a head of the bone anchor, the receiving part having a first end and a second end, a central axis that extends between the first and second ends, and two legs at the first end that define a recess extending in a longitudinal direction transverse to the central axis for receiving the rod, and a monolithic pressure member positionable in the receiving part, the pressure member including a rod support surface and an engagement portion to adjust the pressure member to exert pressure on the head. The engagement portion is positioned farther radially from the central axis in the longitudinal direction than a first portion of the rod support surface, and extends closer axially to the first end of the receiving part than the entire first portion of the rod support surface.

An interspinous fusion device is described. The interspinous fusion device includes a spacer member and an anchor member. The spacer member has a ring with two or more anchor assemblies projecting laterally from substantially opposite sides of the spacer member ring. The spacer member further has a first zip lock flange and a second zip lock flange, each of the first and second zip lock flanges extends transversely from the spacer member ring wherein each of the first and second zip lock flanges each comprises a series of teeth protruding from it. The anchor member has a ring with two or more anchor assemblies projecting laterally from substantially opposite sides of the anchor member ring. The anchor member further has a barrel extending transversely from the anchor member ring. The barrel comprises a first column of recesses adapted to mate with the teeth of the first zip lock flange and a second column of recesses adapted to mate with the teeth of the second zip lock flange. The spacer member is adapted to slide over the barrel of the anchor member such that the series of teeth of the first zip lock flange mates with the recesses in the first column of recesses of the barrel, and the series of teeth of the second zip lock flange mates with the recesses in the second column of recesses of the barrel to secure the spacer member to the anchor member.

A receiver assembly for capturing an elongate rod in a receiver of a bone anchor includes the receiver, a first threaded closure, and a second threaded closure. The receiver includes an upper portion that defines a first channel, interior surfaces that have helically wound thread, and a lower pressure insert that can be positioned within the first channel and has upright arms. Each of the first threaded closure and the second threaded closure have a cylindrical body with an external surface having continuous helically wound thread that can rotatably mate with the helically wound receiver thread. The first threaded closure and the second threaded closure are interchangeable for different locking configurations in the receiver assembly. The first threaded closure has a downward protrusion that can compressively engage the elongate rod. The second threaded closure has a bottom surface that can compressively engage the upright arms of the lower pressure insert.

Systems, methods, and devices for securing a sublaminar band are provided. A sublaminar band clamp system may include a first locking mechanism, a second locking mechanism, and a body. The body may include a first portion comprising a first passage, wherein the first locking mechanism is disposed within the first passage. The body may further include a second portion comprising a second passage, wherein the second locking mechanism is disposed within the second passage. A third passage may extend across the body and may be in fluid communication with the second passage. An opening may be positioned between the first and second portions, and the opening may be in fluid communication with the first passage.

A soft dynamic stabilization assembly includes a core, typically in the form of a tensioned cord, at least one pair of bone anchors, a spacer surrounding the core located between the bone anchors, typically, at least one elastic bumper and at least one fixing or blocking member. The core is slidable with respect to at least one of the bone anchors and cooperating spacer.

A pivotal bone anchor assembly includes a shank having a head portion and an anchor portion for fixation to the bone of a patient, and a receiver comprising a base defining a lower portion of central bore and a pair of upright arms defining a channel for receiving an elongate rod. The assembly also includes a retaining structure with a central opening configured to capture and pivotally retain and support the head portion of the shank in the retaining structure, and which is slidably movable relative to the receiver so as to provide for increased articulated movement between the shank and the receiver prior to locking the assembly with the elongate rod and a closure. The assembly further includes an insert configured to engage the elongate rod and the head portion of the shank when in use, and to have an overlapping configuration with the retaining structure when the assembly is in the locked configuration.

A pivotal bone anchor assembly includes a shank having an anchor portion and a head with a partially spherical outer surface, a drive socket, an annular planar top surface surrounding the drive socket, and a frusto-conical surface between the planar top surface and the partially spherical outer surface. The assembly further includes a receiver having a base defining an axial bore and an upper portion defining a channel configured to receive a rod, and an insert positionable within the axial bore having an upper surface engageable with the rod, a lower surface for transferring a downwardly-directed force toward the head, and a central aperture for accessing the drive socket, with the rod extending across the central aperture when the fixation rod is engaged by the upper surface. After the head, the insert, and the rod are positioned in the receiver, the frusto-conical surface remains spaced apart from the rod to in all pivotal orientations of the shank relative to the receiver.

A dynamic fixation medical implant having at least two bone anchors includes a longitudinal connecting member assembly having rigid sleeves for attachment to the bone anchors, at least one spacer engaging the bone anchors and the sleeves, and in some embodiments, an end elastic bumper. A flexible cord is initially slidingly received within the rigid sleeves, the spacer and the bumper. The spacer may include an optional inelastic inner liner, with at least one of the sleeves having an extension slidingly receivable within the liner. Some sleeves include apertures for receiving a closure top portion for locking the cord against the sleeve, or alternatively receiving a closure top that does not extend into the aperture, the slip or grip option provided by the aperture in each sleeve resulting in an overall connector with variable segmental stiffness.

A tool set for implanting bone screws in a human spine, followed by the implantation of a rod into the bone screws includes end guide tools having flexible back wall flaps that receive opposite ends of the rod and intermediate guide tools that hold the rod in intermediate locations between the end guide tools. Both the end and intermediate guide tools include an attachment structure for operably connecting the guide tool to a bone screw. The attachment structure includes an undercut and/or recess so as to resist splaying and separation of the guide tool from an attached bone screw.