Systems and Methods for Delivering Bone Cement to a Bone Anchor

Abstract

A system for delivering bone cement to a bone anchor includes an anchor connection instrument for releasably connecting to a proximal end of the bone anchor. The anchor connection instrument includes a first member coupled to an opposed second member. The first member and the second member have a distal end configured to releasably connect to the proximal end of the bone anchor. The first member is movable between a release position to facilitate release of the anchor connection instrument from the proximal end of the bone anchor and a connect position in which the first member and the second member connect to the proximal end of the bone anchor. A cement delivery tube is positionable in the passage between the first member and the second member of the anchor connection instrument. A bone cement delivery system is coupled to the tube.

1 . An instrument system for delivering bone cement to a bone anchor, the system comprising:
 an anchor connection instrument for releasably connecting to a proximal end of the bone anchor, the anchor connection instrument including a first member coupled to an opposed second member, at least one of the first member and the second member having a distal end configured to releasably connect to the proximal end of the bone anchor, the first member being movable between a release position to facilitate release of the anchor connection instrument from the proximal end of the bone anchor and a connect position in which at least one of the first member and the second member connect to the proximal end of the bone anchor, the first member and the second member defining a passage therebetween;   a cement delivery tube positionable in the passage between the first member and the second member of the anchor connection instrument, and   a bone cement delivery system coupled to the tube.   
     
     
         2 . The instrument of  claim 1 , further comprising a tube connector positioned within the passage between the first member and the second member of the anchor connection mechanism for connecting the tube to the anchor connection instrument, the tube connector having an opening sized to receive the tube therethrough, the opening sized to permit the tube to move along a longitudinal axis of the tube and sized to restrict motion of the tube in a direction transverse to the tube. 
     
     
         3 . The instrument of  claim 2 , wherein the tube connector is constructed of a polymer material. 
     
     
         4 . The instrument of  claim 1 , wherein the first member is biased to the connect position. 
     
     
         5 . The instrument of  claim 1 , wherein the first member and the second member are pivotally connected and pivot about a pivot axis, the first member and the second member being pivotable between the release position and the connect position. 
     
     
         6 . The instrument of  claim 5 , wherein the first member and the second member each include a proximal handle, manipulation of the proximal handle effecting pivoting of the first member and the second member. 
     
     
         7 . The instrument of  claim 5 , wherein the first member and the second member pivot apart from one another when pivoted to the release position and pivot toward one another when pivoted to the connect position. 
     
     
         8 . The instrument of  claim 7 , wherein the distal end of the first member is configured to engage an exterior of the proximal end of the bone anchor. 
     
     
         9 . The instrument of  claim 8 , wherein the distal end of the first member has a projection for engaging an opening provided on the exterior of the proximal end of the bone anchor. 
     
     
         10 . The instrument of  claim 5 , wherein the first member and the second member pivot toward one another when pivoted to the release position and pivot away from another when pivoted to the connect position. 
     
     
         11 . The instrument of  claim 10 , wherein the distal end of the first member is configured to engage an interior of the proximal end of the bone anchor. 
     
     
         12 . The instrument of  claim 11 , wherein the distal end of the first member has a projection for engaging an internal thread provided on the interior of the proximal end of the bone anchor. 
     
     
         13 . The instrument of  claim 1 , wherein the first member moves apart from the second member when moved to the release position and moves toward the second member when moved to the connect position and the distal end of the first member is configured to engage an exterior of the proximal end of the bone anchor. 
     
     
         14 . The instrument of  claim 1 , wherein the first member moves towards the second member when moved to the release position and moves away from the second member when moved to the connect position and the distal end of the first member is configured to engage an interior of the proximal end of the bone anchor. 
     
     
         15 . The instrument system of  claim 1 , further comprising a valve for selectively interrupting cement delivery through the tube. 
     
     
         16 . The instrument system of  claim 15 , wherein the valve is positioned proximate a distal end of the tube. 
     
     
         17 . The instrument system of  claim 15 , wherein the valve is positioned proximate a proximal end of the tube. 
     
     
         18 . A bone anchor system comprising:
 a plurality of bone anchors, each of the plurality of bone anchors including a proximal end, a distal bone engaging end, a passage extending from an opening at the proximal end to the distal bone engaging end, and an opening in a sidewall of the distal bone engaging end, the opening communicating with the passage,   a bone cement delivery system,   a tube connectable to the bone cement delivery system, the tube being sized to fit within the passage of each of the plurality of bone anchors,   an anchor connection instrument for releasably connecting to a proximal end of the bone anchor, the anchor connection instrument including a first member coupled to an opposed second member, at least one of the first member and the second member having a distal end configured to releasably connect to the proximal end of the bone anchor, the first member being movable between a release position to facilitate release of the anchor connection instrument from the proximal end of the bone anchor and a connect position in which at least one of the first member and the second member connect to the proximal end of the bone anchor, the first member and the second member defining a passage therebetween;   a tube connector positionable within the passage between the first member and the second member of the anchor connection mechanism for connecting the tube to the anchor connection instrument, the tube connector have an opening sized to receive the tube therethrough, the opening sized to permit the tube to move along a longitudinal axis of the tube and sized to restrict motion of the tube in a direction transverse to the tube.   
     
     
         19 . The system of  claim 18  further comprising a plurality of anchor connection instruments, each of the anchor connection instruments releasably connectable to the proximal end of one of the plurality of bone anchors and having a passage for receiving the tube. 
     
     
         20 . The system of  claim 18 , wherein the bone anchors are polyaxial spinal screws, the polyaxial spinal screws having a proximal head configured to receive a spinal rod and a distal bone engaging portion having a screw thread, the distal bone engaging portion being connected to the proximal head and positionable in a plurality of orientations relative to the proximal head. 
     
     
         21 . A method of delivering cement to a bone anchor anchored in a bone of a patient, the method comprising
 moving the distal end of a first member of an anchor connection instrument relative to the distal end of a second member of the anchor connection instrument to separate the distal end of the first member from the distal end of the second member,   positioning the distal end of the first member and the distal end of the second member about the proximal end of a bone anchor,   moving the distal end of a first member relative to the distal end of a second member to move the distal end of the first member toward the distal end of the second member and into contact with the proximal end of bone anchor thereby connecting the anchor instrument to the proximal end of the bone anchor,   advancing a tube through the first member and the second member,   positioning a distal end of the tube into a passage of a bone engaging portion of the bone anchor,   connecting the tube to a bone cement delivery system, and   injecting cement into the passage of the bone anchor through the tube.   
     
     
         22 . The method of  claim 21 , further comprising
 removing the anchor connecting instrument and the tube from the bone anchor,   connecting the anchor connecting instrument the tube to a second bone anchor, and   injecting cement into the second bone anchor through the tube.   
     
     
         23 . The method of  claim 22 , further comprising
 closing a valve associated with the tube to interrupt cement flow to the tube prior to removing the tube from the bone anchor, and   opening the valve prior to injecting cement into the second bone anchor.   
     
     
         24 . The method of  claim 23 , wherein the valve is positioned proximate the distal end of the tube. 
     
     
         25 . The method of  claim 24 , wherein the valve is positioned proximate the proximal end of the tube. 
     
     
         26 . The method of  claim 21 , wherein at least a portion the bone cement delivery system is positioned outside of a fluoroscopic imaging field about the patient. 
     
     
         27 . The method of  claim 21 , wherein the bone anchor includes one or more openings in a sidewall of the bone anchor, the openings communicating with the passage to allow bone cement to be dispensed through one or more of the openings, and
 further comprising adjusting the position of the distal end of the tube within the passage of the bone anchor relative to one or more openings to select the opening through which to dispense bone cement.   
     
     
         28 . A spinal anchor system comprising:
 a plurality of spinal anchors, each of the plurality of spinal anchors including a proximal portion having a slot for receiving a rod, a distal bone engaging portion, a passage extending from an opening in the proximal portion to the distal bone engaging portion, and an opening in a sidewall of the distal bone engaging portion, the opening communicating with the passage, the proximal portion of the spinal anchors including threads for receiving a closure mechanism for securing the rod in the slot,   a bone cement delivery system, and   a tube having a proximal end connectable to the bone cement delivery system and a distal end sized to be positioned within the passage of the distal bone engaging portion of a spine anchor of the plurality of spine anchors, the tube having a connection member positioned between the proximal end and the distal end of the tube a distance from the distal end of the tube selected to allow the distal end of the tube to be advance into the passage of the distal bone engaging portion of a bone anchor, the connection member having a thread configured to engage the thread on the proximal portion of a spinal anchor of the plurality of spinal anchors.   
     
     
         29 . The spinal anchor system of  claim 28 , wherein the plurality of spinal anchors are polyaxial spinal screws in which the proximal portion of a spinal anchor is adjustable relative to the distal bone engaging portion. 
     
     
         30 . The spinal anchor system of  claim 28 , wherein the thread of the connection member is interrupted at two spaced apart, opposed unthreaded sections. 
     
     
         31 . The spinal anchor system of  claim 30 , wherein the connection member is generally disk shaped and the unthreaded sections are diametrically opposed to one another and are separated by a threaded section. 
     
     
         32 . A method of delivering cement to a spinal anchor anchored in a vertebra of a patient, the method comprising:
 advancing a distal end of a bone cement delivery tube through an opening in a proximal portion of a spinal anchor, the proximal portion of the spinal anchor having a slot for receiving a spinal rod and a thread for receiving a closure mechanism for securing the rod in the proximal portion,   advancing the distal end of the bone cement delivery tube into a passage formed in the distal bone engaging portion of the spinal anchor, the passage communicating with the opening in the proximal portion of the spinal anchor,   engaging a thread on a connection mechanism on the bone cement delivery tube with the thread on the proximal portion of the spinal anchor, the connection member positioned between the proximal end and the distal end of the bone cement delivery tube a distance from the distal end of the bone cement delivery tube selected to allow the distal end of the bone cement delivery tube to be advance into the passage of the distal bone engaging portion of a bone anchor,   rotating the connection member to secure the connection member and the bone cement delivery tube to the proximal portion of the spinal anchor,   connecting a proximal end of the bone cement delivery tube to a bone cement delivery system, and   injecting cement into the passage of distal bone engaging portion of the spinal anchor through the bone cement delivery tube.   
     
     
         33 . The method of  claim 32 , wherein at least a portion the bone cement delivery system is positioned outside of a fluoroscopic imaging field about the patient. 
     
     
         34 . The method of  claim 32 , further comprising
 removing the connection member and the tube from the spinal anchor,   advancing a distal end of a bone cement delivery tube through an opening in a proximal portion of a second spinal anchor,   advancing the distal end of the bone cement delivery tube into a passage formed in the distal bone engaging portion of the second spinal anchor,   engaging a thread on a connection mechanism on the bone cement delivery tube with a thread on the proximal portion of the second spinal anchor,   rotating the connection member to secure the connection member and the bone cement delivery tube to the proximal portion of the second spinal anchor, and   injecting cement into the passage of distal bone engaging portion of the spinal anchor through the bone cement delivery tube.   
     
     
         35 . The method of  claim 32 , wherein the thread of the connection member is interrupted at two spaced apart, opposed unthreaded sections and further comprising
 inserting the connection member into the proximal portion of the bone anchor with the unthread sections facing the thread, and   rotating the connection member to engage the thread on the connection member with the thread on the proximal portion of the bone anchor.   
     
     
         36 . A method of stabilizing a first vertebra and a second vertebra of a patient, the method comprising:
 implanting a first bone anchor into the first vertebra, the first bone anchor having a proximal portion for engaging a spinal rod and a distal bone engaging portion,   implanting a second bone anchor into the second vertebra, the second bone anchor having a proximal portion for engaging a spinal rod and a distal bone engaging portion,   connecting an anchor connection instrument to the proximal portion of the first bone anchor,   positioning the distal end of a cement delivery tube into a passage provided through at least a portion of the bone engaging portion of the first bone anchor, the anchor connection instrument connecting the cement delivery tube to the first bone anchor,   delivering bone cement from a bone cement delivery system coupled to the bone cement delivery tube through the passage in the first bone anchor to the first vertebra,   removing the anchor connection instrument and the cement delivery tube from the first bone anchor,   connecting the anchor connection instrument and the cement delivery tube to the second bone anchor,   delivering bone cement from the bone cement delivery system coupled to the bone cement delivery tube through a passage in bone engaging portion of the second bone anchor to the second vertebra, and   connecting a spinal connection element to the first bone anchor and the second bone anchor.   
     
     
         37 . The method of  claim 36 , wherein at least a portion the bone cement delivery system is positioned outside of a fluoroscopic imaging field about the patient. 
     
     
         38 . The method of  claim 36 , further comprising
 closing a valve associated with the cement delivery tube to interrupt cement flow to the cement delivery tube prior to removing the tube from the bone anchor, and   opening the valve prior to injecting cement into the second bone anchor.   
     
     
         39 . The method of  claim 38 , wherein the valve is positioned proximate the distal end of the cement delivery tube. 
     
     
         40 . The method of  claim 38 , wherein the valve is positioned proximate the proximal end of the tube. 
     
     
         41 . The method of  claim 36 , wherein the first bone anchor and the second bone anchor are at least one of a polyaxial screw, a monoaxial screw, or a uniplanar screw. 
     
     
         42 . The method of  claim 36 , wherein the cement delivery system includes a pump for advancing the bone cement through the cement delivery tube. 
     
     
         43 . The method of  claim 42 , wherein the pump is positioned outside of a fluoroscopic imaging field about the patient. 
     
     
         44 . The method of  claim 42 , further comprising reversing operation of the pump to reduce pressure on the bone cement in the cement delivery tube prior to removing the anchor connection instrument and the cement delivery tube from the first bone anchor. 
     
     
         45 . A method of stabilizing a first vertebra and a second vertebra of a patient, the method comprising:
 implanting a first bone anchor into the first vertebra, the first bone anchor having a proximal portion for engaging a spinal rod and a distal bone engaging portion,   implanting a second bone anchor into the second vertebra, the second bone anchor having a proximal portion for engaging a spinal rod and a distal bone engaging portion,   connecting a first anchor connection instrument to the proximal portion of the first bone anchor,   connecting a second anchor connection instrument to the proximal portion of the second bone anchor,   positioning a distal end of a cement delivery tube into a passage provided through at least a portion of the bone engaging portion of the first bone anchor, the first anchor connection instrument connecting the cement delivery tube to the first bone anchor,   delivering bone cement from a bone cement delivery system coupled to the bone cement delivery tube through the passage in the first bone anchor to the first vertebra,   removing the cement delivery tube from the first anchor connection instrument and the first bone anchor,   connecting the cement delivery tube to second anchor connecting instrument connected to the second bone anchor,   delivering bone cement from the bone cement delivery system coupled to the bone cement delivery tube through a passage in bone engaging portion of the second bone anchor to the second vertebra, and   connecting a spinal connection element to the first bone anchor and the second bone anchor.   
     
     
         46 . The method of  claim 45 , wherein at least a portion the bone cement delivery system is positioned outside of a fluoroscopic imaging field about the patient. 
     
     
         47 . The method of  claim 45 , further comprising
 closing a valve associated with the cement delivery tube to interrupt cement flow to the cement delivery tube prior to removing the tube from the bone anchor, and   opening the valve prior to injecting cement into the second bone anchor.   
     
     
         48 . The method of  claim 47 , wherein the valve is positioned proximate the distal end of the cement delivery tube. 
     
     
         49 . The method of  claim 47 , wherein the valve is positioned proximate the proximal end of the tube. 
     
     
         50 . The method of  claim 45 , wherein the first bone anchor and the second bone anchor are at least one of a polyaxial screw, a monoaxial screw, or a uniplanar screw. 
     
     
         51 . The method of  claim 45 , wherein the cement delivery system includes a pump for advancing the bone cement through the cement delivery tube. 
     
     
         52 . The method of  claim 51 , wherein the pump is positioned outside of a fluoroscopic imaging field about the patient. 
     
     
         53 . The method of  claim 52 , further comprising reversing operation of the pump to reduce pressure on the bone cement in the cement delivery tube prior to removing the anchor connection instrument and the cement delivery tube from the first bone anchor. 
     
     
         54 . The method of  claim 45 , wherein the cement delivery tube is connected to the first anchor connection instrument during connection of the first anchor connection instrument to the proximal portion of the first bone anchor. 
     
     
         55 . The method of  claim 45 , wherein the cement delivery tube is connected to the first anchor connection instrument after connection of the first anchor connection instrument to the proximal portion of the first bone anchor. 
     
     
         56 . The method of  claim 45 , wherein the distal end of the cement delivery tube includes an occlusion for blocking cement flow through a portion of the passage in the first bone anchor and the passage of the second bone anchor. 
     
     
         57 . The method of  claim 56 , wherein the distal end of the cement delivery tube includes one or more slots positioned proximal to the occlusion for delivering cement to the passage in the first bone anchor and the passage of the second bone anchor. 
     
     
         58 . The method of  claim 56 , wherein the occlusion is spaced apart from the distal end of the cement delivery tube by a wire. 
     
     
         59 . The method of  claim 45 , wherein the distal end of the cement delivery tube includes a first lengthwise section and a second lengthwise section distal to the first lengthwise section, the first lengthwise section has increased flexibility compared to the first lengthwise section. 
     
     
         60 . An instrument system for delivering bone cement to a bone anchor, the system comprising:
 an anchor connection instrument for releasably connecting to a proximal end of the bone anchor, the anchor connection instrument including an instrument body and a first member movably coupled to the instrument body, the instrument body having a proximal end, a distal end and a passage therebetween, the distal end sized and shaped to be positioned with the proximal end of the bone anchor, the first member configured to releasably connect to the proximal end of the bone anchor, the first member being movable relative to the instrument body between a release position to facilitate release of the anchor connection instrument from the proximal end of the bone anchor and a connect position in which the first member connects to the proximal end of the bone anchor,   a cement delivery tube positionable in the passage of the instrument body of the anchor connection instrument, and   a bone cement delivery system coupled to the tube.   
     
     
         61 . The instrument of  claim 60 , wherein the first member is configured to connect to the interior of the proximal end of the bone anchor. 
     
     
         62 . The instrument of  claim 61 , wherein the first member is a prong having a distal free end and a proximal end connected to the instrument body, the free end moving toward the instrument body in the release position and the free end moving away from the instrument body in the connect position. 
     
     
         63 . The instrument of  claim 60 , wherein the first member is configured to connect to the exterior of the proximal end of the bone anchor. 
     
     
         64 . The instrument of  claim 63 , wherein the first member is pivotally connected to the instrument body, the first member having a proximal handle and a distal end, the distal end moving away from the instrument body in the release position and the distal end moving toward the instrument body in the connect position. 
     
     
         65 . The instrument of  claim 60 , wherein a distal end of the cement delivery tube includes an occlusion for blocking cement flow through a portion of a passage in a bone engaging portion of the bone anchor. 
     
     
         66 . The instrument of  claim 65 , wherein the distal end of the cement delivery tube includes one or more slots positioned proximal to the occlusion for delivering cement to the passage in the bone engaging portion of the bone anchor. 
     
     
         67 . The instrument of  claim 65 , wherein the occlusion is spaced apart from the distal end of the cement delivery tube by a wire. 
     
     
         68 . The instrument of  claim 60 , wherein a distal end of the cement delivery tube includes a first lengthwise section and a second lengthwise section distal to the first lengthwise section, the first lengthwise section has increased flexibility compared to the first lengthwise section. 
     
     
         69 . The instrument of  claim 60 , wherein the distal end of the instrument body comprises a connection member positioned with the passage and longitudinally adjustable relative to the instrument body between an extended position and a retracted position. 
     
     
         70 . The instrument of  claim 69  wherein the instrument body includes a spring that biases the instrument body to the extended position. 
     
     
         71 . The instrument of  claim 69 , wherein the connection member includes a cylindrical body and an enlarged distal end having an arcuate distal surface. 
     
     
         72 . A spinal anchor system comprising:
 a plurality of spinal anchors, each of the plurality of spinal anchors including a proximal portion having a slot for receiving a rod, a distal bone engaging portion, a passage extending from an opening in the proximal portion to the distal bone engaging portion, and an opening in a sidewall of the distal bone engaging portion, the opening communicating with the passage, the proximal portion of the spinal anchors including threads for receiving a closure mechanism for securing the rod in the slot,   a screw extension connectable to one of the plurality of bone anchors,   a bone cement delivery system,   a cement delivery tube having a proximal end connectable to the bone cement delivery system and a distal end sized to be positioned within the passage of the distal bone engaging portion of a spine anchor of the plurality of spine anchors, and   an anchor connection instrument having an instrument body having a proximal end, a distal end, and a passage therebetween for receiving the cement delivery tube, the distal end of the anchor connection instrument including a first connection feature configure to connect to the proximal portion of one of the bone anchors and a second connection feature configured to connect to the distal bone engaging portion of the bone anchor.   
     
     
         73 . The system of  claim 72 , wherein the first connection feature of the anchor connection instrument comprises an externally threaded section for threadingly engaging an internal thread provided on the proximal portion of the bone anchor. 
     
     
         74 . The system of  claim 73 , wherein the second connection feature of the anchor connection instrument comprises a drive tip for engaging a drive feature on a proximal end of the bone engaging portion of the bone anchor.