Device for delivering bone cement to bone screws - Patents.com

Abstract

Disclosed herein are instruments and methods for delivering bone cement. In one exemplary embodiment, the instrument includes a cannulated bone screw, a cannulated shaft, and a retaining sleeve. The cannulated bone screw has a head configured to be received within a rod receiver and a shank configured to extend distally from the head and to extend distally from the rod receiver. The cannulated shaft has a distal end configured to extend within the shank of the cannulated bone screw and a proximal end configured to couple to a bone cement delivery system. The retaining sleeve is disposed around at least a portion of the cannulated shaft. The head of the bone screw has a proximal recess and a distal recess therein. The distal end of the retaining sleeve is configured to couple to the proximal recess.

Description

[Technical field]

[0001] SUMMARY OF THE DISCLOSURE Instruments and methods are provided for delivering bone cement to bone screws. [Background technology]

[0002] Bone screws, such as pedicle screws, can be used in orthopedic surgery to fix bones during healing, fusion, or other procedures. In spinal surgery, for example, bone screws can be used to attach spinal fixation elements to one or more vertebrae to provide rigid or dynamic fixation of the spine.

[0003] In many instances, particularly in spinal surgery, patients may have weakened or osteoporotic bone quality that reduces the engagement of the bone screw in such bone structures. As a result, this may prevent stabilization of the vertebrae and may result in the bone screw loosening or backing out. To improve fixation of the bone screw, bone cement may be introduced into the bone adjacent to the bone screw.

[0004] Bone screw augmentation typically involves the use of a cannulated / fenestrated bone screw to inject bone cement into the bone structure having the fenestrated bone screw therein. For example, once the cannulated / fenestrated bone screw is inserted into the bone, a cannula and / or guide may be docked to the head assembly. The docked cannula and / or guide serves as an alignment guide to the shank of the bone screw, allowing access to the fenestration of the shank. Cement delivery is then performed by inserting the cement delivery shaft through the docked cannula and / or guide into the shank of the bone screw, and pumping bone cement through the shaft into the shank of the bone screw. However, in use, the cannula and / or guide must be coupled to the head assembly to ensure proper alignment of the cannula and / or guide with the shank, which can be challenging, especially when direct visualization of the bone screw is not possible / difficult. Clinically, this can impede intraoperative stability, interfere with procedural workflow, and increase the number of surgical steps. Furthermore, because the cannula and / or guide act as an alignment guide for cement delivery, insufficient connection to the head assembly and / or misalignment with the shank of the bone screw can result in cement leakage from the cement delivery shaft or failure of the shaft. Summary of the Invention [Problem to be solved by the invention]

[0005] Thus, a need remains for improved instruments and methods associated with delivering bone cement to bone screws. [Means for solving the problem]

[0006] Various instruments and methods are disclosed for delivering bone cement to bone screws.

[0007] In one embodiment, an instrument is provided that includes a cannulated bone screw, a cannulated shaft, and a retaining sleeve disposed about at least a portion of the cannulated shaft. The cannulated bone screw has a head configured to be received within a rod receiver and a shank configured to extend distally from the head and to extend distally from the rod receiver. The head has a proximal recess and a distal recess therein. The cannulated shaft has a distal end configured to extend within the shank of the cannulated bone screw and a proximal end configured to couple to a bone cement delivery system. The retaining sleeve has a distal end configured to couple to the proximal recess of the head of the bone screw.

[0008] In some embodiments, the instrument can include a coupling assembly configured to selectively couple the cannulated shaft to the retaining sleeve to prevent axial translation of the cannulated shaft relative to the retaining sleeve.

[0009] The coupling assembly can have a variety of configurations. In some embodiments, the coupling assembly can be coupled to a proximal end of the retaining sleeve. For example, a distal end of the coupling assembly can be threadably coupled to a proximal end of the retaining sleeve.

[0010] In some embodiments, the coupling assembly can include a release mechanism that can be configured to selectively disengage the cannulated shaft from the retaining sleeve. The release mechanism can have a channel extending therethrough that can at least partially overlap with a lumen extending through the annulus such that the coupling assembly can be disposed about a portion of the cannulated shaft. The coupling assembly can also include a biasing element that can bias the release mechanism toward the groove in the cannulated shaft.

[0011] The cannulated bone screw may have a variety of configurations. In some embodiments, the proximal recess of the cannulated bone screw may be threaded, and the distal end of the retaining sleeve may be threadably coupled to the threaded proximal recess.

[0012] In another exemplary embodiment, an instrument is provided having a cannulated bone screw, a cannulated shaft, and a guide assembly disposed partially around the cannulated shaft. The cannulated bone screw has a head configured to couple to a rod receiver and a shank extending distally from the head, the head having proximal and distal recesses therein. The cannulated shaft has a distal end configured to extend into the shank of the bone screw and a proximal end configured to couple to a bone cement delivery system, such that bone cement can be delivered through the cannulated shaft into the shank of the bone screw. The guide assembly includes a guide sleeve having a distal end configured to couple to the proximal recess in the head of the bone screw, and a locking mechanism configured to couple to the proximal end of the guide sleeve. The locking mechanism is configured to selectively lock the cannulated shaft and the guide sleeve together to prevent longitudinal movement of the cannulated shaft relative to the guide sleeve. In some embodiments, the distal end of the locking mechanism can be configured to threadably couple to the proximal end of the retaining sleeve.

[0013] The locking mechanism may have a variety of configurations. For example, in some embodiments, the locking mechanism may include a release mechanism that may be configured to selectively engage a groove in the cannulated shaft. The locking mechanism may include a biasing element that may bias the release mechanism toward the groove in the cannulated shaft. The locking mechanism may include an annular body having a first portion, a second portion, and a lumen extending therebetween, with the release mechanism being partially housed within the first portion of the annular body. The release mechanism may have a channel extending therethrough, with the channel at least partially overlapping the lumen of the annular body.

[0014] A method for delivering bone cement to a bone screw is also provided. In one exemplary embodiment, the method can include implanting a cannulated bone screw into a bone, the bone screw having a head configured to couple to a rod receiver and a shank extending distally from the head. The head has a proximal recess and a distal recess therein, the proximal recess being threadably coupled to a distal end of a retaining sleeve on an instrument. The method can also include inserting a distal end of the cannulated shaft through the retaining sleeve and into the shank of the bone screw, and injecting cement through the cannulated shaft and into the shank of the bone screw.

[0015] In some embodiments, implanting the cannulated bone screw into the bone includes rotating a retaining sleeve relative to a screw drive assembly on the instrument to threadably engage a distal end of the retaining sleeve with a proximal recess of the bone screw, rotating the screw drive assembly to drive the bone screw into the bone, and removing the screw drive assembly from the instrument with the retaining sleeve remaining threadably engaged to the bone screw.

[0016] In some embodiments, the proximal end of the retaining sleeve can be coupled to a coupling assembly having a release mechanism, and insertion of the distal end of the cannulated shaft can cause the release mechanism to engage a portion of the cannulated shaft when the distal end reaches a predetermined insertion depth within the bone screw. In such embodiments, the method can include disengaging the release mechanism from the cannulated shaft to allow the cannulated shaft to be translated proximally and removed from the bone screw.

[0017] In some embodiments, the method may include coupling the proximal end of the cannulated shaft to a bone cement delivery system prior to injecting the cement, hi other embodiments, the method may include coupling the rod receiver to the head of the bone screw after injecting the cement. [Brief description of the drawings]

[0018] The invention will be more fully understood from the following detailed description when read in conjunction with the accompanying drawings, in which: [Figure 1] FIG. 1 is a perspective view of one embodiment of an instrument for delivering bone cement to a screw. [Diagram 2] FIG. 2 is a partially exploded view of the device of FIG. 1. [Figure 3A] FIG. 2 is a top view of the device of FIG. 1. [Figure 3B] FIG. 3B is a cross-sectional view of the device of FIG. 3A taken along line 3-3. [Figure 4] FIG. 3C is an enlarged cross-sectional view of the device of FIG. 3B taken through box 4. [Diagram 5] FIG. 3C is an enlarged cross-sectional view of the device of FIG. 3B taken through box 5. [Figure 6] FIG. 1 illustrates a cross-sectional view of one embodiment of a bone screw assembly. [Figure 7] 13 is a perspective view of another embodiment of an instrument for delivering bone cement to a bone screw. [Figure 8] FIG. 8 is a partial exploded view of the device of FIG. [Figure 9A] FIG. 9 is a side view of the device of FIG. 8. [Figure 9B] FIG. 9B is a cross-sectional view of the device of FIG. 9A taken along line 9-9. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Certain representative embodiments will now be described to provide an overall understanding of the principles of the structure, function, manufacture, and use of the devices and methods disclosed herein. One or more examples of these embodiments are illustrated in the accompanying drawings. Those skilled in the art will appreciate that the devices, systems, and methods detailed herein and illustrated in the accompanying drawings are non-limiting exemplary embodiments, and that the scope of the invention is defined solely by the claims. Features illustrated or described in connection with one exemplary embodiment may be combined with features of other embodiments. Such modifications and variations are intended to be within the scope of the invention.

[0020] Various instruments and methods are provided for delivering bone cement to bone screws. In some embodiments, the instruments and methods allow for driving the bone screw into the bone and then maintaining a connection between the bone screw and the instrument. This connection allows for direct access to the implanted bone screw, e.g., for subsequent cement delivery, before a rod receiver, e.g., a U-shaped rod receiver, is attached to the head of the bone screw. Furthermore, this connection can help control the alignment with the implanted bone screw, thereby aiding in access to the implanted bone screw. Thus, delivery of cement to the implanted bone screw can be performed without the need to attach the rod receiver and dock a separate alignment guide thereto. As a result, this can provide intra-operative stability early in the surgical procedure, streamline the procedure workflow, reduce the number of surgical steps, and therefore the surgical time.

[0021] The exemplary instruments, as described herein and shown in the drawings, may include various features to facilitate delivery of bone cement to the bone screws. However, those skilled in the art will understand that the instruments may include only some of these features and / or may include various other features known in the art. The instruments described herein are intended only to represent certain exemplary embodiments.

[0022] 1-5 illustrate one exemplary embodiment of an instrument 100 configured to deliver bone cement directly into a bone screw 102 prior to coupling of a rod receiver (not shown). The illustrated instrument 100 generally includes a cannulated shaft 104, a retaining sleeve 106, also referred to herein as a guide sleeve, disposed about a portion of the cannulated shaft 104, and a coupling assembly 108, also referred to herein as a locking mechanism. Collectively, the guide sleeve and locking mechanism are generally referred to herein as a guide assembly. For purposes of brevity, certain components of the instrument 100 are not shown in FIGS. 1-3B.

[0023] Although the bone screw 102 may have a variety of configurations, as shown in FIGS. 1-3B and 5, the bone screw 102 has a head 112 and a shank 114 extending distally from the head 112. The head 112 may have a variety of shapes and sizes. As shown, the head 112 is generally in the shape of a truncated sphere and includes a proximal recess 116 and a distal recess 118 defined therein. The proximal recess 116 may be substantially cylindrical with internal threads 120 formed therein for engaging a corresponding threaded portion of the retaining sleeve 106, as described below. The distal recess 118 may be shaped to non-rotatably engage the distal tip of a driver shaft (not shown), as described below. For example, the distal recess 118 may be in the form of a female mating feature (e.g., a hexagonal recess) and the distal tip of the driver shaft may be in the form of a male mating feature (e.g., a hexagonal protrusion) such that the distal tip of the driver shaft can mate with the bone screw 102. In this exemplary embodiment, the head 112 includes a threaded proximal recess 116 and a distal recess 118 that is not threaded.

[0024] Additionally, the head 112 is configured to be coupled to a rod receiver. In this manner, once the cement has been delivered to the bone screw 102 and the instrument 100 has been removed from the bone screw 102, the head 112 of the bone screw 102 is exposed and is then attached to a rod receiver to form a bone screw assembly, as discussed in more detail below. An exemplary bone screw assembly 300 is shown in FIG. 6, in which a rod receiver 382 is attached to the head 312 of the cannulated bone screw 302. While the rod receiver 382 can have a variety of configurations, in the illustrated embodiment, the rod receiver 382 is substantially U-shaped. In other embodiments, the rod receiver 382 can have other suitable configurations, such as a rod receiver with a closed throughbore or a substantially C-shaped rod receiver. In some embodiments, the bone screw assembly is a polyaxial bone screw assembly. Those skilled in the art will appreciate that the head of the cannulated bone screw can have other suitable shapes and sizes. Exemplary embodiments of suitable bone screws and bone screw assemblies are described in more detail in U.S. Patent Application Publication Nos. 2018 / 0014858 and 2018 / 0014862, each of which is incorporated by reference in its entirety.

[0025] The shank 114 of the bone screw 102 can have a variety of shapes and sizes. As shown, the shank 114 is in the form of an elongated body having threads 124 formed on at least a portion of its outer surface 126. The illustrated shank 114 includes a lumen 128 extending therethrough. In other embodiments, the lumen 128 may extend through only a portion of the shank 114. The lumen 128 is in fluid communication with the proximal recess 116 and the distal recess 118 of the head 112. As a result, the distal end 104d of the cannulated shaft 104 can be inserted through the head 112 of the bone screw 102 and into at least a portion of the shank 114, as shown in FIGS. 1-3B and 5, such that bone cement can be delivered through the shaft 104 and into the bone screw 102. The shank 114 may also include at least one fenestration 130, e.g., an opening, extending outwardly from the lumen 128 to the outer surface 126 of the shank 114. The at least one fenestration 130 is configured to direct bone cement injected into the bone screw 102, e.g., when the bone screw 102 is implanted, toward the bone proximate the bone screw 102. The location and number of fenestrations within the shank 114 of the bone screw 102 may vary.

[0026] As shown in FIGS. 1-3B and 5, the retaining sleeve 106 is coupled to the head 112 of the bone screw 102. While the retaining sleeve 106 can have a variety of configurations, in this illustrated embodiment, the retaining sleeve 106 has an elongated cylindrical shape extending from a proximal end 106p to a distal end 106d. The distal end 106d of the retaining sleeve 106 is configured to couple to the head 112 of the bone screw 102 for subsequently delivering bone cement to the bone screw 102. The retaining sleeve 106 also includes a lumen 134 that is configured to receive a component (e.g., a driver shaft for driving the bone screw 102 into bone, the cannulated shaft 104 as shown in FIGS. 1-3B and 4). In this illustrated embodiment, the lumen 134 is aligned along the longitudinal axis (L) of the instrument. I) from the proximal end 106p to the distal end 106d of the retaining sleeve 106. As a result, as shown in Figures 1-3B and 5, the retaining sleeve 106 can act as a guide for the cannulated shaft 104 that is inserted through the retaining sleeve 106 into the associated bone screw 102. This allows cement to be delivered into the bone screw 102 prior to attachment of a rod receiver to the head 112 of the bone screw 102.

[0027] As shown, the distal end 106d of the retaining sleeve 106 includes threads 132 that threadably engage corresponding internal threads 120 in the proximal recess 116 of the head 112 of the bone screw 102. The retaining sleeve 106 is thus threadably coupled to the bone screw 102 itself. Those skilled in the art will appreciate that the retaining sleeve 106 and bone screw 102 may be coupled to one another using other coupling mechanisms. For example, in other embodiments, the head of the bone screw may have an outer surface configured to couple to an inner surface of the retaining sleeve via a press fit (e.g., a collet mechanism).

[0028] 1-4, the proximal end 106p of the retaining sleeve 106 is attached to the coupling assembly 108. The proximal end 106p of the retaining sleeve 106 includes a proximal cavity 136 having internal threads 138 that are threadably engaged with a threaded portion of the coupling assembly 108. The proximal end 106p also extends laterally (e.g., parallel to the longitudinal axis (L) of the instrument) through a wall 109 of the retaining sleeve 106. I The connector assembly 108 includes a first channel 135 and a second channel 137 that extend in a direction perpendicular to the longitudinal axis (L) of the instrument. The first channel 135 and the second channel 137 communicate with corresponding third channels 139 and fourth channels 140 that extend laterally through the wall 110 of the connector assembly 108 (e.g., perpendicular to the longitudinal axis (L) of the instrument). I)). Specifically, first channel 135 and third channel 139 are engaged with one another via a first set pin 143, and second channel 137 and fourth channel 140 are engaged with one another via a second set pin 144. In this manner, during use, retaining sleeve 106 and coupling assembly 108 are prevented from loosening their threaded engagement with one another and, as a result, from becoming separated from one another. Those skilled in the art will appreciate that retaining sleeve 106 and coupling assembly 108 may be coupled to one another using other coupling mechanisms, or that retaining sleeve 106 and coupling assembly 108 may be formed together from a single continuous profile.

[0029] The linking assembly can have a variety of configurations. The illustrated linking assembly 108 includes an elongated tubular body 146 having a proximal end 148, a distal end 150, and a lumen 152 extending therebetween, as shown in FIGS. 1-4. The lumen 152 is adapted to receive an instrument (L). I 3B and 4 , distal end 150 includes external threads 154 that are threadably engaged with internal threads 138 of proximal cavity 136 of retaining sleeve 106, and includes third and fourth channels 139 and 140 that engage first and second channels 135 and 137 of proximal cavity 136 via corresponding set pins 143, 144, respectively. Proximal end 148 of annular body 146 includes an opening 156 that extends radially outward from lumen 152 and through outer surface 146a of annular body 146.

[0030] The coupling assembly may also include a release mechanism, such as a release button. As shown, the coupling assembly 108 includes a release button 158 that is partially received within the proximal end 148 of the annular body 146. While the release button 158 may have a variety of configurations, in this illustrated embodiment, the release button 158 is substantially rectangular in shape and includes a first portion 160a and a second portion 160b. Additionally, a channel 161 extends from the first surface 159a to the second surface 159b of the release button 158. As shown in FIGS. 3B and 4, the channel 161 at least partially overlaps with the lumen 152 of the annular body 146. As a result, the coupling assembly 108 is disposed about a portion of the cannulated shaft 104, as shown in FIGS. 1 and 3A-4.

[0031] Additionally, the release button 158 is coupled to a biasing element 162 that is configured to bias a first portion 160a of the release button 158 toward the lumen 142 of the annular body 146 and bias a second portion 160b of the release button 158 away from the lumen 142 of the annular body. While the biasing element 162 can have a variety of configurations, the biasing element 162 is in the form of a helical spring, as shown in Figures 2, 3B, and 4.

[0032] The coupling assembly 108 is configured to selectively couple components, such as the driver shaft and cannulated shaft 104 of the screw drive assembly, to the retaining sleeve 106, as shown in Figures 1 and 3A-4. In use, the bone screw 102 can be inserted into bone using a screw drive assembly (not shown) that is releasably coupled to the retaining sleeve 106 via the coupling assembly 108. The screw drive assembly and the retaining sleeve 106 are collectively referred to herein as a screw insertion instrument. The screw drive assembly can include a handle and a driver shaft coupled to the handle. The driver shaft can be inserted through the retaining sleeve 106 to engage the distal recess 118 of the bone screw 102 and drive the bone screw 102 into bone. Thus, the bone screw 102 may be coupled to the screw insertion instrument, for example, by inserting the distal tip of the driver shaft into the distal recess 118 of the head 112 of the bone screw 102 and threadably engaging the distal end 106d of the retaining sleeve 106 with the proximal recess 116 of the head 112 of the bone screw 102. The bone screw 102 may be driven into bone by rotating the screw drive assembly relative to the retaining sleeve 106. Further details regarding other exemplary embodiments of the screw drive assembly and screw insertion instrument can be found, for example, in U.S. patent application Ser. No. __ (Attorney Docket No. MED6016USNP1 / 47061-019F01US), entitled "Screw Inserter Instruments and Methods," filed on June 13, 2019, and Ser. No. __ (Attorney Docket No. MED6016USNP2 / 47061-019F02US), each of which is incorporated by reference in its entirety herein.

[0033] Once the bone screw 102 is inserted into the bone, the screw drive assembly is separated (e.g., by depressing the second portion 160b of the release button 158 of the coupling assembly 108) and removed from the retaining sleeve 106, i.e., the screw drive assembly is removed from the bone screw 102 while the retaining sleeve 106 remains threadably engaged to the bone screw 102. As a result, once the screw drive assembly is removed, the cannulated shaft 104 can be inserted into and coupled to the retaining sleeve 106 via the coupling assembly 108, as shown in FIGS. 1 and 3A-4. In this manner, the retaining sleeve 106 can function as an alignment guide, providing access to the bone screw after its insertion so that bone cement can be injected therein. This avoids the need to couple, e.g., thread, a separate alignment guide to the bone screw 102 for guiding the cannulated shaft 104, and thus the bone cement, to the bone screw 102.

[0034] Although the cannulated shaft 104 may have a variety of configurations, the cannulated shaft 104 is generally in the form of an elongated hollow tube extending from a proximal end 104p to a distal end 104d of the cannulated shaft 104, as shown in FIGS. 1-3B. The distal end 104d extends into a portion of the bone screw 102. The proximal end 104p of the cannulated shaft 104 is configured to be coupled (e.g., threadably coupled) to a bone cement delivery system (not shown) such that bone cement may be delivered from the system through the cannulated shaft 104 and into the bone screw 102. As will be appreciated by one of ordinary skill in the art, any bone cement delivery system may be configured to couple to the cannulated shaft 104 and deliver bone cement therethrough. Exemplary embodiments of bone cement delivery systems can be found in U.S. Pat. Nos. 7,097,648, 8,360,629, 8,415,407, and 9,381,024, as well as U.S. Patent Application Publication Nos. 2006 / 0264967, 2007 / 0032567, 2008 / 0228192, and 2010 / 0114174, each of which is incorporated by reference in its entirety herein.

[0035] As shown in Figures 3B and 4, the cannulated shaft 104 is coupled to the retaining sleeve 106 via a coupling assembly 108. In this exemplary embodiment, the release button 158 engages a groove 105 in the cannulated shaft 104 adjacent the proximal end 104p of the cannulated shaft 104. Specifically, the first portion 160a is configured to engage the groove 105, and the second portion 160b is configured to be spaced a distance (D) from the groove 105. This distance allows the second portion 160b to be selectively pressed toward the groove 105 to move the first portion 160a away from the groove 105, thereby separating the cannulated shaft 104 and the retaining sleeve 106, as described in more detail below. As shown in Figure 3B, in the expanded configuration, the release button 158 is engaged to the cannulated shaft 104 via a biasing element 162. As a result, a first portion 160a of the release button 158 is biased towards the groove 105 and a second portion 160b of the release button 158 is biased away from the groove 105 a distance (D).

[0036] In use, the cannulated shaft 104 is inserted into the retaining sleeve 106 until the first portion 160a of the release button 158 slides into contact and engages the groove 105 of the cannulated shaft 104. In this manner, the distal end 104d of the cannulated shaft 104 is inserted into the bone screw 102 to a predetermined insertion depth. Once bone cement has been delivered through the cannulated shaft 104 and into the bone screw 102 (e.g., when a desired amount of bone cement has been injected into the bone screw), the cannulated shaft 104 may be removed from the retaining sleeve 106. To remove the cannulated shaft 104 from the retaining sleeve 106, the release button 158 may be actuated to move the first portion 160a of the release button 158 away from and thus disengage the groove 105. For example, a user can actuate the release button 158 by applying sufficient force to the second portion 160b to move the second portion 160b toward the groove 105. This causes the first portion 160a of the release button 158 to shift away from the groove 105 and the biasing element 162 to move to the compressed configuration. As a result, the first portion 160a of the release button 158 disengages from the groove 105 of the cannulated shaft 104, thereby allowing the cannulated shaft 104 to be slidably removed (e.g., translated proximally) from at least the bone screw 102.

[0037] Figures 7-9B show another embodiment of an instrument 200 configured to deliver bone cement to a bone screw 202. Other than the differences described in detail below, the instrument 200 is similar to the instrument 100 shown in Figures 1-4, and thus the common elements will not be described in further detail herein. Additionally, for the sake of brevity, certain components of the instrument 200 are not shown in Figures 7-9B.

[0038] In the illustrated embodiment, the instrument 200 includes an alignment guide 264, a cannulated shaft 204 extending therethrough, and a coupling element 266 configured to releasably couple the cannulated shaft 204 to the alignment guide 264.

[0039] Once the bone screw 202 is inserted into the bone, the alignment guide 264 may be coupled to the head 212 of the bone screw 202. The alignment guide 264 may have a variety of configurations. In the illustrated embodiment, the alignment guide 264 is in the form of a generally elongated hollow tube extending from a proximal end 264p to a distal end 264d. The distal end 264d includes a threaded portion 268a and a non-threaded portion 268b extending distally therefrom. The threaded portion 268a includes threads 269 that threadably engage corresponding internal threads 220 of the proximal recess 216 of the head 212 of the bone screw 202, as shown in FIGS. 7-9B. The non-threaded portion 268b is formed within the distal recess 218 of the head 212 of the bone screw 202. Additionally, proximal end 264p of alignment guide 264 includes an annular collar 270 having a connection mechanism 271 configured to engage coupling element 266, as shown in Figures 7-9B. In this exemplary embodiment, connection mechanism 271 is an annular groove or notch. In other embodiments, connection mechanism 271 can have other configurations.

[0040] Cannulated shaft 204 may have a variety of configurations, but as illustrated, cannulated shaft 204 is generally in the form of an elongated hollow tube extending from a proximal end 204p to a distal end 204d. Distal end 204d extends into a portion of bone screw 202. Cannulated shaft 204 further includes a ferrule 272 extending radially outward from an outer surface 273a of cannulated shaft 204. ferrule 272 is interposed between first segment 274a and second segment 274b of cannulated shaft 204. ferrule 272 may have a variety of shapes and sizes. In this exemplary embodiment, ferrule 272 has a substantially conical configuration. The ferrule 272 is configured to contact a tapered portion 275 of the inner surface 265 of the alignment guide 264 to limit the insertion depth of the distal end 204d of the cannulated shaft 204 into the bone screw 202. As a result, this contact between the ferrule 272 and the tapered portion 275 may prevent a user from inserting the distal end 204d of the cannulated shaft 204 too deeply into or completely through the bone screw 202.

[0041] As shown, the connecting element 266 is fixedly attached to the cannulated shaft 204. The connecting element 266 can have a variety of configurations. In the illustrated embodiment, the connecting element 266 includes a hollow tubular base member 276 having two spaced apart arms 278, 280 extending radially outward therefrom. A distal end 276d of the tubular base member 276 is fixedly coupled to the proximal-most end 204a of the cannulated shaft 204. A proximal end 276p of the tubular base member 276 is configured to be coupled (e.g., threadably coupled) to a bone cement delivery system (not shown) such that bone cement can be delivered from the system through the tubular base member 276 and the cannulated shaft 204 and into the bone screw 202. As will be appreciated by those skilled in the art, any bone cement delivery system may be configured to couple to and deliver bone cement therethrough the tubular base member 276. Exemplary embodiments of bone cement delivery systems can be found in the previously referenced U.S. Patent Nos. 7,097,648, 8,360,629, 8,415,407, and 9,381,024, as well as U.S. Patent Application Publication Nos. 2006 / 0264967, 2007 / 0032567, 2008 / 0228192, and 2010 / 0114174, each of which is incorporated herein by reference in its entirety.

[0042] 7-9B, the cannulated shaft 204 is releasably coupled to the alignment guide 264 via two spaced apart arms 278, 280 of the coupling element 266. Specifically, a distal end 278d, 280d of each arm 278, 280 engages with a connection mechanism 271 of the alignment guide 264. In use, the distal ends 278d, 280d of the arms 278, 280 can engage with the connection mechanism 271 either by sliding or by snap-fit. To separate the cannulated shaft 204 from the alignment guide 264, the proximal ends 278p, 280p of the arms 278, 280 can be compressed together to move the distal ends 278d, 280d away from each other and disengage from the connection mechanism 271. Once the distal ends 278d, 280d are disengaged, the cannulated shaft 204 can be removed.

[0043] The instruments disclosed herein can be designed to be disposed of after a single use, or they can be designed to be used multiple times. In either case, however, the instrument can be reconditioned after at least one use and reused. Reconditioning can include any combination of disassembly of the instrument, followed by cleaning or replacement of particular parts, and subsequent reassembly. In particular, the instrument can be disassembled and any number of particular parts or pieces of the instrument can be selectively replaced or removed in any combination. Upon cleaning and / or replacement of particular parts, the instrument can be reassembled for later use at a reconditioning facility or by a surgical team immediately prior to a surgical procedure. Those skilled in the art will appreciate that reconditioning of an instrument may utilize a variety of techniques for disassembly, cleaning / replacement, and reassembly. The use of such techniques, and the resulting reconditioned instrument, are all within the scope of the present application.

[0044] Furthermore, in this disclosure, like-named components of the embodiments generally have similar characteristics, and therefore, in a particular embodiment, each feature of each like-named component is not necessarily described in full detail. Additionally, to the extent that linear or circular dimensions are used in describing the disclosed systems, instruments, and methods, such dimensions are not intended to limit the types of shapes that can be used in conjunction with such systems, instruments, and methods. Those skilled in the art will recognize that equivalent dimensions of such linear and circular dimensions can be readily determined for any geometric shape. The size and shape of the systems and instruments, and their components, may depend at least on the subject's anatomical structure within which the systems and instruments are used, the size and shape of the components with which the systems and instruments are used, and the methods and procedures in which the systems and instruments are used.

[0045] It will be appreciated that the terms "proximal" and "distal" are used herein with reference to a user, such as a clinician, holding the handle of the instrument. Other spatial terms, such as "forward" and "rearward," similarly correspond to distal and proximal, respectively. It will be further appreciated that for convenience and clarity of illustration, spatial terms such as "vertical" and "horizontal" are used herein with respect to the drawings. However, surgical instruments are used in many orientations and positions, and these spatial terms are not intended to be limiting and absolute.

[0046] Values ​​or ranges can be expressed herein as "about" and / or "approximately" from one particular value to another particular value. When values ​​or ranges are expressed in such a manner, other disclosed embodiments include the recited particular value and / or from the one particular value to the other particular value. Similarly, when values ​​are expressed in an approximation format by use of the antecedent "about," it will be understood that a number of disclosed values ​​are recited, and that the particular values ​​form another embodiment. It will be further understood that there are a number of disclosed values, and that each value is herein disclosed as being "about" in addition to the particular value itself. In some embodiments, "about" can be used to mean, for example, within 10% of the recited value, within 5% of the recited value, or within 2% of the recited value.

[0047] For purposes of describing and defining the present teachings, unless otherwise noted, it should be noted that the term "substantially" is utilized herein to represent the inherent degree of uncertainty that may result from any quantitative comparison, value, measurement, or other representation.

[0048] Those skilled in the art will recognize further features and advantages of the present invention based on the embodiments described above. Thus, the present invention is not limited by what has been specifically shown and described, except as indicated by the appended claims. All publications and documents cited herein are expressly incorporated herein in their entirety. Any patents, publications or information that are incorporated herein by reference in whole or in part are incorporated herein only to the extent that the incorporated material does not conflict with existing definitions, descriptions, or other disclosed material set forth in this document. Thus, the disclosures expressly set forth herein shall take precedence over any conflicting documents incorporated herein.

[0049] [Embodiment] (1) An apparatus for delivering bone cement to a bone screw, comprising: a cannulated bone screw having a head configured to be received within a rod receiver and a shank extending distally from the head and configured to extend distally from the rod receiver, the head having proximal and distal recesses therein; a cannulated shaft having a distal end configured to extend into the shank of the cannulated bone screw and a proximal end configured to couple to a bone cement delivery system; and a retaining sleeve disposed about at least a portion of the cannulated shaft, the retaining sleeve having a distal end configured to couple to the proximal recess in the head of the bone screw; An apparatus comprising: (2) The instrument of embodiment 1, further comprising a coupling assembly configured to selectively couple the cannulated shaft to the retaining sleeve to prevent axial translation of the cannulated shaft relative to the retaining sleeve. (3) The instrument of embodiment 2, wherein the coupling assembly includes a release mechanism configured to selectively disengage the cannulated shaft from the retaining sleeve. (4) The instrument of embodiment 3, wherein the coupling assembly includes a biasing element that biases the release mechanism toward the groove in the cannulated shaft. (5) the release mechanism has a channel extending therethrough; the channel at least partially overlaps a lumen extending through the annulus, and the coupling assembly is disposed about a portion of the cannulated shaft. An apparatus as described in embodiment 2 or 3.

[0050] (6) The device of any one of embodiments 2 to 5, wherein the connecting assembly is connected to the proximal end of the retaining sleeve. (7) The device of embodiment 6, wherein a distal end of the connecting assembly is threadably connected to the proximal end of the retaining sleeve. (8) the proximal recess of the cannulated bone screw is threaded; the distal end of the retaining sleeve is threadably coupled to the proximal recess; An apparatus according to any one of embodiments 1 to 7. (9) An apparatus for delivering bone cement to a bone screw, comprising: a cannulated bone screw having a head adapted to couple to a rod receiver and a shank extending distally from said head, said head having proximal and distal recesses therein; a cannulated shaft having a distal end configured to extend into the shank of the bone screw and a proximal end configured to be coupled to a bone cement delivery system, wherein bone cement may be delivered through the cannulated shaft into the shank of the bone screw; and a guide assembly disposed partially about the cannulated shaft, the guide assembly including a guide sleeve having a distal end configured to couple to the proximal recess in the head of the bone screw, and a locking mechanism configured to couple to a proximal end of the guide sleeve, the locking mechanism configured to selectively lock the cannulated shaft and the guide sleeve together to prevent longitudinal movement of the cannulated shaft relative to the guide sleeve; An apparatus comprising: (10) The device of embodiment 9, wherein a distal end of the locking mechanism is configured to be threadably coupled to the proximal end of the retaining sleeve.

[0051] (11) The instrument of any one of claims 9 to 10, wherein the locking mechanism includes a release mechanism configured to selectively engage a groove in the cannulated shaft. (12) The instrument of claim 11, wherein the locking mechanism includes a biasing element that biases the release mechanism toward the groove in the cannulated shaft. (13) The locking mechanism further comprises an annular body having a first portion, a second portion, and a lumen extending therebetween; the release mechanism being partially contained within the first portion of the annular body; 13. An apparatus as described in embodiment 11 or 12. (14) The release mechanism has a channel extending therethrough; the channel at least partially overlaps the lumen of the toroid; An apparatus as described in embodiment 13. (15) A method for delivering bone cement to a bone screw, comprising: implanting a cannulated bone screw into a bone, the bone screw having a head configured to couple to a rod receiver and a shank extending distally from the head, the head having proximal and distal recesses therein, the proximal recess being threadably coupled to a distal end of a retaining sleeve on an instrument; inserting a distal end of a cannulated shaft through the retaining sleeve and into the shank of the bone screw; injecting cement through the cannulated shaft and into the shank of the bone screw; A method comprising:

[0052] (16) The method of embodiment 15, further comprising coupling the proximal end of the cannulated shaft to a bone cement delivery system prior to injecting the cement. (17) Implanting the cannulated bone screw into bone comprises: rotating the retaining sleeve relative to a screw drive assembly on the instrument to threadably engage the distal end of the retaining sleeve with the proximal recess of the bone screw; rotating the screw drive assembly to drive the bone screw into bone; and removing the screw drive assembly from the instrument while leaving the retaining sleeve threadably engaged with the bone screw. 17. The method according to embodiment 15 or 16. (18) The proximal end of the retaining sleeve is coupled to a coupling assembly having a release mechanism; inserting the distal end of the cannulated shaft so that the release mechanism engages a portion of the cannulated shaft when the distal end reaches a predetermined insertion depth within the bone screw; The method according to any one of embodiments 15 to 17. 19. The method of claim 18, further comprising disengaging the release mechanism from the cannulated shaft to permit proximal translation and removal of the cannulated shaft from the bone screw. (20) After cement injection, 20. The method of any one of claims 15 to 19, further comprising coupling a rod receiver to the head of the bone screw.

Claims

1. An apparatus comprising: a cannulated bone screw having a head configured to be received within a rod receiver and a shank configured to extend distally from said head and to extend distally from said rod receiver, said head having proximal and distal recesses therein; a cannulated shaft having a distal end configured to extend into the shank of the cannulated bone screw and a proximal end configured to couple to a bone cement delivery system; a retaining sleeve disposed about at least a portion of the cannulated shaft, the retaining sleeve having a distal end configured to couple to the proximal recess in the head of the cannulated bone screw; a driver shaft having a distal end that releasably engages the distal recess, the driver shaft being used to drive the cannulated bone screw into bone; Equipped with wherein when the retaining sleeve is coupled to the proximal recess, the driver shaft is moved in the distal direction through the lumen of the retaining sleeve such that the distal end of the driver shaft engages the distal recess and the driver shaft is rotated to drive the cannulated bone screw into bone, and then the distal end of the driver shaft is removed from the distal recess and the driver shaft is withdrawn from the retaining sleeve, and thereafter the cannulated shaft is moved in the distal direction through the lumen of the retaining sleeve such that the distal end of the cannulated shaft extends into the shank of the cannulated bone screw and bone cement delivered from the bone cement delivery system is directed through the cannulated shaft and into the cannulated bone screw.

2. The instrument of claim 1 , further comprising a coupling assembly configured to selectively couple the cannulated shaft to the retaining sleeve to prevent axial translation of the cannulated shaft relative to the retaining sleeve.

3. The instrument of claim 2 , wherein the coupling assembly includes a release mechanism configured to selectively disengage the cannulated shaft from the retaining sleeve.

4. The instrument of claim 3 , wherein the coupling assembly includes a biasing element that biases the release mechanism toward a groove in the cannulated shaft.

5. the release mechanism having a channel extending therethrough; the channel at least partially overlaps a lumen extending through the annulus, and the coupling assembly is disposed about a portion of the cannulated shaft.

4. The device of claim 3.

6. The device of any one of claims 2 to 5, wherein the coupling assembly is coupled to the proximal end of the retaining sleeve.

7. The instrument of claim 6 , wherein a distal end of the coupling assembly is threadably coupled to the proximal end of the retaining sleeve.

8. the proximal recess of the cannulated bone screw is threaded; the distal end of the retaining sleeve is threadably coupled to the proximal recess; An apparatus according to any one of claims 1 to 7.

9. An apparatus comprising: a cannulated bone screw having a head adapted to couple to a rod receiver and a shank extending distally from said head, said head having proximal and distal recesses therein; a cannulated shaft having a distal end configured to extend into the shank of the cannulated bone screw and a proximal end configured to be coupled to a bone cement delivery system, wherein bone cement may be delivered through the cannulated shaft into the shank of the cannulated bone screw; a guide assembly disposed partially about the cannulated shaft, the guide assembly including a guide sleeve having a distal end configured to couple to the proximal recess in the head of the cannulated bone screw, and a locking mechanism configured to couple to a proximal end of the guide sleeve, the locking mechanism configured to selectively lock the cannulated shaft and the guide sleeve together to prevent longitudinal movement of the cannulated shaft relative to the guide sleeve; and a driver shaft having a distal end that releasably engages the distal recess, the driver shaft being used to drive the cannulated bone screw into bone; Equipped with wherein when the guide sleeve is coupled to the proximal recess, the driver shaft is moved in the distal direction through the lumen of the guide sleeve until the distal end of the driver shaft engages the distal recess and the driver shaft is rotated to drive the cannulated bone screw into bone, and then the distal end of the driver shaft is removed from the distal recess and the driver shaft is withdrawn from the guide sleeve, and thereafter the cannulated shaft is moved in the distal direction through the lumen of the guide sleeve until the distal end of the cannulated shaft extends into the shank of the cannulated bone screw and bone cement delivered from the bone cement delivery system is directed through the cannulated shaft and into the cannulated bone screw.

10. The instrument of claim 9 , wherein a distal end of the locking mechanism is configured to threadably couple to the proximal end of the guide sleeve.

11. 11. The instrument of claim 9 or 10, wherein the locking mechanism includes a release mechanism configured to selectively engage a groove in the cannulated shaft.

12. The instrument of claim 11 , wherein the locking mechanism includes a biasing element that biases the release mechanism toward the groove in the cannulated shaft.

13. the locking mechanism further comprises an annular body having a first portion, a second portion and a lumen extending therebetween; the release mechanism being partially contained within the first portion of the annulus; 13. An apparatus as claimed in claim 11 or 12.

14. the release mechanism having a channel extending therethrough; the channel at least partially overlaps the lumen of the toroid; 14. The device of claim 13.

Images