Deflection rod system dimensioned for deflection to a load characteristic for dynamic stabilization and motion preservation spinal implantation system and method

Abstract

A dynamic stabilization, motion preservation spinal implant system includes an anchor system, a horizontal rod system and a vertical rod system. The systems are modular so that various constructs and configurations can be created and customized to a patient.

1 .- 9 . (canceled) 
     
     
         10 . A dynamic spine stabilization implant adapted to be implanted in a spine of a patient comprising:
 an anchor adapted to be inserted into bone of the patient;   a body including a shield with a shield cavity, the shield cavity having a first end and an open end and a shield cavity axis, said body extending from said anchor;   a deflection rod having a first end and a proximal end and a longitudinal axis, the deflection rod mounted in said shield cavity such that the first end of the deflection rod is connected to the first end of the shield cavity, and the proximal end extends out of the open end of the shield cavity; and the longitudinal axis is aligned with the shield cavity axis;   the deflection rod including a shaft extending from the connection of the deflection rod and the shield cavity and out of the open end of the shield cavity;   said shield cavity extending along said shaft of said deflection rod;   a gap defined between said deflection rod and said shield, said gap extending from the open end of the shield cavity at least partway along the shield cavity towards the first end of the shield cavity and said gap extending along the shaft of said deflection rod;   said gap being configured to allow deflection of the deflection rod within the shield cavity to thereby allow deflection of the proximal end of the deflection rod away from alignment with the shield cavity axis in response to a load applied to the proximal end of the deflection rod; and   wherein said deflection of the proximal end of the deflection rod away from alignment with the shield cavity axis is limited by contact between the shaft of the deflection rod and the shield cavity.   
     
     
         11 . The implant of  claim 10 , wherein said deflection rod increases in effective stiffness after an amount of deflection of said proximal end of the deflection rod. 
     
     
         12 . The implant of  claim 10 , wherein said gap is an annular gap. 
     
     
         13 . A dynamic spine stabilization implant adapted to be implanted in a spine of a patient comprising:
 an anchor adapted to be inserted into bone of the patient;   a body including a shield with a shield cavity, the shield cavity having a first end and an open end, said body extending from said anchor;   a deflection rod having a first end and a proximal end and a longitudinal axis, the deflection rod mounted in said shield cavity such that the first end is secured in the first end of the shield cavity and the proximal end extends out of the open end of the shield cavity; and   said deflection rod being spaced from said shield along a first portion of said deflection rod extending from the proximal end such that said first portion of said deflection rod is configured for deflection perpendicular to the longitudinal axis in response to a load applied to the proximal end of the deflection rod, said deflection of said first portion of said deflection rod being limited by the shield cavity.   
     
     
         14 . A dynamic spine stabilization implant adapted to be implanted in a spine of a patient comprising:
 an anchor adapted to be inserted into bone of the patient;   a body including a shield with a shield cavity, the shield cavity having a first end and an open end and a shield cavity axis, said body extending from said anchor;   a deflection rod having a first end and a proximal end and a longitudinal axis, the deflection rod mounted in said shield cavity such that the first end is secured in the first end of the shield cavity, and the proximal end extends out of the open end of the shield cavity;   a gap defined between said deflection rod and said shield, said gap extending from the open end of the shield cavity at least partway along the shield cavity towards the first end of the shield cavity, said gap extending along said deflection rod;   said gap being configured to allow deflection of the deflection rod within the shield cavity to thereby allow deflection of the proximal end of the deflection rod in response to a load applied to the proximal end of the deflection rod; and   wherein said deflection of the proximal end of the deflection rod is limited by contact between the deflection rod and the shield cavity.   
     
     
         15 . A dynamic spine stabilization implant comprising:
 an anchor adapted to be inserted into the bone of a patient, the anchor having a longitudinal axis;   an anchor head extending from said anchor;   a deflection cavity in said anchor head, said deflection cavity having a deflection cavity wall, and an open end and a closed end;   a deflection rod having a first end secured at the closed end of the deflection cavity and a proximal end extending out of the open end of the deflection cavity and said cavity wall extends along said deflection rod;   wherein the dynamic spine stabilization implant is configured such that a load applied to the proximal end of the deflection rod causes resilient deflection of the proximal end of the deflection rod; and   wherein resilient deflection of the proximal end of the deflection rod is limited by contact between the proximal end of the deflection rod and the deflection cavity wall.   
     
     
         16 . The implant of  claim 15 , wherein the deflection cavity is cone-shaped and decreases in diameter going in a direction away from the open end of said deflection cavity. 
     
     
         17 . The implant of  claim 15 , wherein the spine implant is configured such that a load applied to the proximal portion of the deflection rod causes resilient deflection of the proximal portion of the deflection rod away from alignment with the longitudinal axis of the bone anchor by bending of the deflection rod. 
     
     
         18 . The implant of  claim 15 , further comprising a connector at the proximal end of the deflection rod configured for mounting a spinal rod to the deflection rod without preventing deflection of the deflection rod. 
     
     
         19 . The implant of  claim 15  wherein the resilient deflection is resisted by a force acting perpendicular to the deflection rod. 
     
     
         20 . The implant of  claim 15  wherein the resilient deflection is resisted by a force action inside of the cavity located between the open end and the closed end of the deflection cavity. 
     
     
         21 . The implant of  claim 15  wherein the contact which limits resilient deflection between the proximal portion of the deflection rod and the deflection wall cavity occurs between the open end of the deflection cavity and the closed end of the deflection cavity along the cavity wall. 
     
     
         22 . The implant of  claim 15  wherein the resilient deflection is resisted by a force acting inside of said cavity. 
     
     
         23 . The implant of  claim 15  wherein the resilient deflection is resisted by a material located inside of said cavity. 
     
     
         24 . A dynamic spine stabilization implant comprising:
 an anchor adapted to be inserted into the bone of a patient, the anchor having a longitudinal axis;   an anchor head extending from said anchor;   said anchor head including a deflection cavity aligned with the longitudinal axis of the anchor;   said deflection cavity having a deflection cavity wall, a first end with an opening through the anchor head and a second end internal to the anchor head;   a deflection rod provided in said deflection cavity;   said deflection rod having a distal portion connected to the deflection cavity and a proximal portion extending out of the opening of the deflection cavity;   the deflection rod including a shaft extending from the connection of the deflection rod and the deflection cavity and through the opening in the anchor head;   said cavity wall extending along said shaft of said deflection rod;   wherein the dynamic spine stabilization implant is configured such that a load applied to the proximal portion of the deflection rod causes resilient deflection of the proximal portion of the deflection rod; and   wherein resilient deflection of the proximal end of the deflection rod is limited by contact along said shaft between the proximal portion of the deflection rod and the deflection cavity wall.   
     
     
         25 . The implant of  claim 24  wherein said deflection cavity diminishes in diameter going from the first end toward the second end. 
     
     
         26 . The implant of  claim 24  wherein the resilient deflection is resisted by a force acting perpendicular to the deflection rod. 
     
     
         27 . The implant of  claim 24  wherein the resilient deflection is resisted by a force acting inside of the cavity located between the first end and the second end of the deflection cavity. 
     
     
         28 . The implant of  claim 24  wherein the contact which controls resilient deflection between the proximal portion of the deflection rod and the deflection cavity occurs between the first end of the deflection cavity and the second end of the deflection cavity along the cavity wall. 
     
     
         29 . The implant of  claim 24  wherein the resilient deflection is resisted by a force acting inside of said cavity. 
     
     
         30 . The implant of  claim 24  wherein the resilient deflection is resisted by a material located inside of said cavity. 
     
     
         31 . A dynamic spine stabilization implant comprising:
 an anchor adapted to be inserted into the bone of a patient;   an anchor head extending from said anchor;   said anchor head including a deflection cavity;   the deflection cavity having an open end, a closed end, a longitudinal axis and a cavity wall;   a deflection rod provided in said deflection cavity;   a distal end of the deflection rod connected to the closed end of the deflection cavity;   a proximal end of the deflection rod extending out of the open end of the deflection cavity;   the deflection rod including a shaft extending from the connection of the distal end of the deflection rod and the closed end of the deflection cavity past the open end of the deflection cavity;   said cavity wall extending along said shaft of said deflection rod;   the deflection rod being spaced from the wall of the deflection cavity at the open end by a gap which diminishes in size toward the closed end of the deflection cavity;   wherein said dynamic spine implant is configured such that the proximal end of the deflection rod can resiliently deflect in response to a load applied to the proximal end of the deflection rod; and   wherein contact along said shaft with the cavity wall limits resilient deflection of the proximal end of the deflection rod in response to a load applied to the proximal end of the deflection rod.   
     
     
         32 . The implant of  claim 31 , further comprising a connector at the proximal end of the deflection rod configured for mounting a spinal rod to the deflection rod without preventing deflection of the deflection rod. 
     
     
         33 . The implant of  claim 31 , wherein the longitudinal axis of the deflection cavity is in-line with a longitudinal axis of the anchor. 
     
     
         34 . The implant of  claim 31  wherein the resilient deflection is caused by a force acting perpendicular to the deflection rod. 
     
     
         35 . The implant of  claim 31  wherein the resilient deflection is caused by a force action perpendicular to the cavity wall located between the open end and the closed end of the deflection cavity. 
     
     
         36 . The implant of  claim 31  wherein the contact which limits resilient deflection between the proximal portion of the deflection rod and the deflection cavity wall occurs between the open end of the deflection cavity and the closed end of the deflection cavity along the cavity wall. 
     
     
         37 . The implant of  claim 31  wherein the resilient deflection is caused by a force acting inside of said cavity. 
     
     
         38 . The implant of  claim 31  wherein the resilient deflection is caused by a material located inside of said cavity. 
     
     
         39 . A dynamic spine stabilization implant comprising:
 an anchor adapted to be inserted into the bone of a patient;   an anchor head having a deflection cavity, the deflection cavity having a deflection cavity wall, a central axis, and a deflection cavity opening;   a deflection rod having a distal end secured within said deflection cavity and a proximal end extending out of the deflection cavity opening, and said cavity wall extends along said deflection rod;   a gap located between the deflection cavity wall and the deflection rod at the deflection cavity opening which gap diminishes in size towards the distal end of the deflection rod; and   wherein the proximal end of the deflection rod can resiliently deflect in response to a load applied to the proximal end of the deflection rod and wherein contact between the deflection rod and the deflection cavity wall limits deflection of the deflection rod.   
     
     
         40 . The implant of  claim 39 , further comprising a connector at the proximal end of the deflection rod configured for mounting a spinal rod to the deflection rod without preventing deflection of the deflection rod. 
     
     
         41 . The implant of  claim 39 , wherein the central axis of the deflection cavity is in-line with a longitudinal axis of the anchor. 
     
     
         42 . The implant of  claim 39 , where, in the absence of deflection of the deflection rod, the deflection rod and the bone anchor are colinear. 
     
     
         43 . The implant of  claim 39  wherein the resilient deflection is resisted by a force acting perpendicular to the deflection rod. 
     
     
         44 . The implant of  claim 39  wherein the resilient deflection is resisted by a force action inside of the cavity located between the deflection cavity opening and the distal ending of the deflection rod. 
     
     
         45 . The implant of  claim 39  wherein the contact which limits resilient deflection between the proximal portion of the deflection rod and the deflection cavity wall occurs between the open end of the deflection cavity and a closed end of the deflection cavity along the cavity wall. 
     
     
         46 . The implant of  claim 39  wherein the resilient deflection is resisted by a forced acting inside of said cavity. 
     
     
         47 . The implant of  claim 39  wherein the resilient deflection is resisted by a material located inside of said cavity.