An improved dynamic longitudinal connecting member includes a rod portion joined with a tensioned cord portion, for use in a medical implant assembly having at least two bone attachment structures, a spacer covering the join of the rod and cord portions and extending between the at least two bone attachment structures, a sleeve, a bumper and a cord blocker. The spacer and bumper are compressed. The cord portion is slidable with respect to at least one of the bone attachment members.

A method of preparing a spinal rod includes obtaining a body that is elongate along a central rod axis and includes a proximal end and a distal end spaced from each other along a longitudinal direction to as to define the spinal rod. The body defines an outer surface extending between the proximal and distal ends and the body comprises a material that is malleable so as to allow the spinal rod to be bent to a predetermined curvature. The method includes producing at least one longitudinal line on the outer surface, such that the at least one longitudinal line is elongate along the longitudinal direction and parallel with the central rod axis. The method also includes producing a plurality of harsh marks incrementally spaced along the outer surface and producing reference numbers on the outer surface. Each of the reference numbers identifies a distance along the longitudinal direction from the proximal end of the body to a respective one of the hash marks.

An implant for the stabilization of bones or vertebrae is provided, the implant being a solid body including a longitudinal axis that defines a longitudinal direction and including a flexible section that has a surface and has a length in the longitudinal direction, the flexible section including at least one cavity located near the surface and having a width in the longitudinal direction that is smaller than the length of the flexible section, the at least one cavity being connected to the surface through at least one slit, and a width of the slit in the longitudinal direction being smaller than the width of the cavity.

A system for flexibly stabilizing a vertebral motion segment by connecting a first vertebra and a second vertebra is disclosed. The system includes an elongate connection element with end portions interconnected by a flexible coupling member. The system includes first and second attachment portions for connecting the connection element to the vertebrae. A first resilient member is positioned between the first end portion and the first attachment portion, and a second resilient member is positioned between the first attachment portion and the second attachment portion. The system is designed such that the second resilient member is compressed when the first and second attachment portions move towards each other, and the first resilient member is compressed when the first and second attachment portions extend away from each other.

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.

A pivotal bone anchor assembly includes a shank having a shank head and an anchor portion, and a receiver having a first channel for receiving a rod and an axial bore for receiving the shank head, with the axial bore including a downwardly-facing abutment surface and opposed rotation blocking and alignment structures beneath a helically wound thread. The assembly also includes a pressure insert having a second channel and opposite outwardly-projecting flanges with notches formed therein. The pressure insert is top loaded into a first position within the axial bore with the second channel in a mal-aligned position relative to the first channel, with subsequent rotation of the pressure insert moving the second channel into alignment with the first channel, the opposite outwardly-projecting flanges under the downwardly-facing abutment surface, and the opposed rotation blocking and alignment structures into the notches formed into the opposite outwardly-projecting flanges.

An apparatus includes a first flexible connector and a second flexible connector. The apparatus also includes a first bone anchor including a first tethering head configured to receive a first portion of the first flexible connector. The apparatus also includes a second bone anchor including a second tethering head configured to receive a second portion of the first flexible connector. The apparatus also includes a third bone anchor defining a first aperture configured to receive therethrough the first bone anchor. The third bone anchor also defines a first peripheral channel configured to receive a first portion of the second flexible connector. The apparatus also includes a fourth bone anchor defining a second aperture configured to receive therethrough the second bone anchor. The fourth bone anchor also defines a second peripheral channel configured to receive a second portion of the second flexible connector.

A method of assembling a pivotal bone anchor assembly includes positioning a retaining structure into a central bore of a receiver having a planar seating surface above a lower opening, the retaining structure being operably slidably coupled with the planar seating surface and having a central opening, the receiver including upright arms defining an open channel configured to receive a rod and exterior surfaces comprising opposite cylindrical upper side surfaces defining a first width and opposite lower side surfaces below the upper side surfaces defining a second width. The method also includes positioning a partially spherical head of a shank into the central opening of the retaining structure, with the retaining structure being slidably movable along the planar seating surface of the receiver to provide for increased articulated movement between the shank and the receiver in at least one direction relative to a vertical centerline axis of the receiver prior to locking the assembly with a closure.

A spinal fixation construct for aligning vertebral bodies includes a bone screw, a spinal rod, a flexible member, and a fixation member. The spinal rod is disposed within a saddle portion of a housing of the bone screw, and includes an elongated body having a first end and a second end. The spinal rod is formed from a first material having a first modulus of elasticity. The flexible member is coupled to the spinal rod, and includes an elongated body having a first end portion and a second end portion. The flexible member is formed from a second material having a second modulus of elasticity that is different from the first modulus of elasticity. The fixation member includes a threaded body portion and a head portion defining a hole therethrough. A portion of the flexible member extends through the hole of the head portion.

A dynamic fixation medical implant having at least two bone anchors includes a longitudinal connecting member assembly having at least one transition portion and cooperating outer sleeve, both the transition portion and sleeve being disposed between the two bone anchors. The transition portion includes a rigid length or rod having apertures therein and a molded plastic length that extends through the apertures, thus attaching the plastic length to the rigid length. The sleeve surrounds the transition portion and extends between the pair of bone anchors, the sleeve being compressible in a longitudinal direction between the bone anchors.