Uniplanar bone anchor system

Abstract

The present teachings provide one or more surgical implements for repairing damaged tissue, such as in the case of a spinal fixation procedure. A uniplanar bone anchor system for a fixation procedure is provided. The system can include a bone fastener including a head with a bearing surface and a shaft adapted to engage an anatomy. The system can also include a saddle, which can include a first bore formed about a longitudinal axis that receives the bone fastener and a coupling bore defined transverse to the longitudinal axis. The system can also include a coupling system, which can have a second bearing surface. The coupling system can be received through the coupling bore such that the second bearing surface of the coupling system can contact the bearing surface to permit the bone fastener to move in only one plane.

1 - 20 . (canceled) 
     
     
         21 . A bone anchor system comprising:
 a bone fastener including a head and a shaft, the head including an arcuate bearing surface;   a saddle comprising:
 opposing arms extending along a longitudinal axis to form a U-shape at a proximal end; 
 a bore formed about the longitudinal axis at a distal end that receives the head of the bone fastener and includes a first bore sidewall and an opposing second bore sidewall; 
 at least one coupling bore defined transverse to the longitudinal axis and extending through a portion of the first bore sidewall and a portion of the second bore sidewall; and 
   a first insert received within the at least one coupling bore, including through the portion of the first bore sidewall and the portion of the second bore sidewall, to capture the bone fastener within the first bore and engage at least a portion of the arcuate bearing surface;   wherein the at least one coupling bore is offset from the longitudinal axis.   
     
     
         22 . The system of  claim 21  wherein the first insert is received within the at least one coupling bore to permit the bone fastener to articulate relative to the saddle in a single plane. 
     
     
         23 . The system of  claim 22  wherein the first insert includes a bearing surface that engages at least a portion of the arcuate bearing surface of the head and cooperates with the bore to permit the bone fastener to articulate relative to the saddle in the single plane. 
     
     
         24 . The bone anchor system of  claim 23 , further comprising:
 a second insert including a bearing surface that engages at least a portion of the arcuate bearing surface of the head and cooperates with the bore to permit the bone fastener to articulate relative to the saddle in the single plane.   
     
     
         25 . The bone anchor system of  claim 21 , wherein:
 the first bore sidewall of the bore covers an entire first sidewall of the head of the bone fastener; and   the second bore sidewall of the bore covers an entire second sidewall of the head of the bone fastener.   
     
     
         26 . The bone anchor system of  claim 21  wherein the head of the bone fastener includes a first planar sidewall surface, and an opposed second planar sidewall surface. 
     
     
         27 . The bone anchor system of  claim 26 , wherein the first planar sidewall surface of the head of the bone fastener engages at least a portion of the first bore sidewall within the bore, and the second planar sidewall surface of the head of the bone fastener engages at least a portion of the second bore sidewall within the bore. 
     
     
         28 . The bone anchor system of  claim 26 , wherein the first planar sidewall surface and the second planar sidewall surface of the head cooperate with the first bore sidewall and the opposing second bore sidewall of the bore to prevent motion of the bone fastener relative to the first bore sidewall and the opposing second bore sidewall of the bore. 
     
     
         29 . A uniplanar bone implant comprising:
 a bone fastener including a head and a shaft, the head including a first arcuate bearing surface, and a second arcuate bearing surface;   a saddle comprising:
 opposing arms extending along a longitudinal axis to form a U-shape at a proximal end; 
 a bore formed about the longitudinal axis at a distal end that receives the head of the bone fastener and includes a first bore sidewall and an opposing second bore sidewall; 
   a first insert received within a first coupling bore to capture the bone fastener within the bore of the saddle, and engage the first arcuate bearing surface of the head.   
     
     
         30 . The system of  claim 29  wherein the first insert is received within the first coupling bore to restrict movement of the bone fastener relative to the saddle to permit articulation in a single plane. 
     
     
         31 . The uniplanar bone implant of  claim 30 , further comprising:
 a second insert received within a second coupling bore to capture the bone fastener within the bore of the saddle and cooperate with internal surfaces of the bore of the saddle to restrict movement of the bone fastener relative to the saddle to permit articulation in a single plane.   
     
     
         32 . The uniplanar bone implant of  claim 31  wherein a bearing surface of the first insert engages the first arcuate bearing surface of the head and a bearing surface of the second insert engages the second arcuate bearing surface of the head. 
     
     
         33 . The uniplanar bone implant of  claim 29  wherein the head of the bone fastener includes a first planar sidewall surface, an opposed second planar sidewall surface, a first stepped surface, and a second stepped surface. 
     
     
         34 . The uniplanar bone implant of  claim 33 , wherein the first stepped surface and second stepped surface cooperate with a portion of a pressure cap to fixedly lock the bone fastener within the saddle. 
     
     
         35 . The uniplanar bone implant of  claim 34 , wherein the pressure cap is disposed within the bore of the saddle, the pressure cap including an inferior surface shaped to distribute forces along the head of the bone fastener. 
     
     
         36 . The uniplanar bone implant of  claim 35 , wherein the pressure cap includes a superior surface for receiving a connecting rod disposed within the U-shape of the saddle. 
     
     
         37 . The uniplanar bone implant of  claim 36 , wherein an inferior surface of the pressure cap includes a plurality of teeth. 
     
     
         38 . The uniplanar bone implant of  claim 37 , wherein the plurality of teeth engage the first stepped surface and the second stepped surface of the bone fastener to fixedly lock the bone fastener to the saddle. 
     
     
         39 . The uniplanar bone implant of  claim 34 , wherein the bore of the saddle is configured to mate with the pressure cap.