Dynamic spinal stabilization with rod-cord longitudinal connecting members

A medical implant assembly having at least two bone attachment structures cooperating with longitudinal connecting members, the longitudinal connecting members being captured by a closure for locking each of the bone attachment structures, the medical implant assembly comprising:

• an elongated solid rod member having a portion at one end thereof attached to a tensionable core member, the rod member devoid of a central passageway along an entire length thereof and having a non-threaded outer surface along an entire length thereof, the rod member being secured to at least one bone attachment structure by direct engagement with the closure;
• the core member extending between the two bone attachment structures and being in slidable relation with at least one of the two bone attachment structures when the bone attachment structures are locked by the closures;
• and
• a compressible outer first member positioned entirely between two adjacent bone attachment structures, wherein the compressible first member surrounds and engages a portion of the core member and the first member being held in compression between the two bone attachment structures when the core member is tensioned,
• wherein the core member is held in tension by a two-part end structure including a threaded fastener in direct clamping engagement with the core member, and wherein the fastener is secured to the core member after the core member is tensioned and the two-part end structure is compressed against a compressible outer second member.

A medical implant assembly having at least two bone attachment structures cooperating with longitudinal connecting members, the longitudinal connecting members being captured by a closure, the medical implant assembly comprises:

• an elongated solid rod member having a portion at one end thereof attached to a tensionable core member with an outer non-threaded surface along an entire length thereof, the rod member being secured to a first bone attachment structure by a closure and the core member extending entirely through at least one additional bone attachment structure and in slidable relation therewith, such that the core member slides freely with respect to the at least one additional bone attachment structure when the rod member is secured and locked by a closure in the first bone attachment structure;
• and
• a compressible outer first member being located entirely between two adjacent bone attachment structures and engaging a portion of the rod member and surrounding a portion of the core member, respectively, and being held in compression between the two bone attachment structures when the core member is held in tensioned by and releasably secured to a two-part end structure including a threaded fastener in direct clamping engagement with the core member, and wherein the fastener is secured to the core member after the core member is tensioned and the two-part end structure is compressed against a compressible outer second member.

A medical implant assembly having at least three bone attachment structures cooperating with longitudinal connecting members, the longitudinal connecting members being captured by a closure, the medical implant assembly comprising:

• an elongated solid rod member attached to a tensionable core member, the rod member being secured to at least one bone attachment structure, the core member extending between at least two of the bone attachment structures;
• and
• a compressible outer sleeve being positioned entirely between two adjacent bone attachment structures;
• wherein the compressible sleeve engages a portion of the rod member and surrounds a portion of the core member, the sleeve being held in compression between the two bone attachment structures when the core member is tensioned,
• wherein the core member extends entirely through at least one bone attachment structure, the core member being in slidable relation with one of the bone attachment structures such that the core member slides freely with respect to the one of the bone attachment structures when the rod member is secured by the closure to the at least one bone attachment structure, and
• wherein the core member is held in tension by a two-part end structure including a threaded fastener in direct clamping engagement with the core member, and wherein the fastener is secured to the core member after the core member is tensioned and the two-part end structure is compressed against a compressible outer member.