Polyaxial screw insertion instrument and method

Abstract

The present disclosure relates generally to surgical instruments for delivering locking or set screws (110) to secure a rod or spinal fastening element relative to an implantable bone anchor or other spinal fastening construct during spinal surgery. In one embodiment, an inserter instrument (100) includes an inner driver shaft (102), a ratcheting outer sleeve (104), and a handle (106) configured to receive the shaft and the sleeve therein. The inner driver shaft can receive a plurality of set screws on a distal end thereof. A side latch, pawl, or button (178) engages the ratcheting outer sleeve to facilitate stepwise advancement of the sleeve relative to the driver shaft for set screw delivery. Stepwise advancement can be controlled using another button that causes movement of the side latch.

Description

Multi-set screw insertion instruments and methods Technical Field

[0001] This disclosure relates generally to surgical instruments and methods of use, and more specifically to surgical instruments for delivering locking or set screws during spinal surgery to secure a rod or spinal fastening element relative to an implanted bone anchor or other spinal fastening construct. Background Technology

[0002] During spinal surgery procedures, such as those used to correct deformities in the spine, fastening structures are often assembled to maintain the spine in a desired shape. Such structures typically include multiple implanted bone anchors along multiple vertebrae; and connected spinal fastening elements, such as rods, which are received within the head of each of these bone anchors and secured using set screws. In many cases, the bone anchors are first implanted into the vertebrae, then the rods are positioned relative to the heads of the bone anchors, and set screws are applied to secure the rods relative to each bone anchor.

[0003] The current posterior fastening system utilizing the aforementioned implanted bone anchors and spinal fastening rods or elements coupled to these anchors requires the delivery of a set screw to each implanted anchor to secure the rod relative to the anchor. For each set screw / implanted anchor, the user must attach the set screw to an insertion device and deliver the assembly to the implanted bone anchor, typically via a narrow extension tube, guide, or other instrument extending from the implanted bone anchor away from the patient's body and toward the user performing the surgery. Alternatively, in many cases, a first user, such as an assistant, loads the set screw onto the insertion device and passes the assembly to a second user, such as a surgeon, who introduces the assembly into the patient and delivers the set screw. The second user then returns the insertion device to the first user for reloading, and this process is repeated for each implanted bone anchor—where several bone anchors may be present, particularly in spinal deformity correction procedures where particularly long spinal fastening constructs may be assembled. This process requires a certain amount of surgical time, which can become significant. Each transfer also increases the complexity and risk of the procedure, as components may be mishandled or discarded.

[0004] Therefore, there is a need for improved instruments and methods for delivering set screws, including improved instruments and methods for delivering multiple set screws during spinal surgery to secure components to bone anchors while minimizing the loading time of the instruments. Summary of the Invention

[0005] This disclosure relates in general to a multi-set screw insertion device and method of use that addresses the challenges of existing methods. The multi-set screw insertion device disclosed herein reduces the number of times the device is passed between the surgeon and assistant while maintaining the ability to deliver set screws for attachment to spinal surgical instruments. Generally, the multi-set screw insertion device disclosed herein may include: an inner actuator shaft on which a plurality of set screws are stacked; and an outer actuator sleeve having a ratchet portion for progressively advancing the set screws along the inner actuator shaft for insertion into bone anchors and other spinal instruments. The inner actuator shaft and outer sleeve may be received within a handle having a button for actuating the device. Actuation of the device causes relative movement between the inner actuator shaft and the outer sleeve to sequentially eject the set screws from the device into the head of a bone anchor receiver or other spinal instruments.

[0006] In one aspect, a surgical instrument is provided, the surgical instrument comprising: a shaft having a distal portion configured to drive a set screw and to hold a plurality of set screws stacked abutting against each other on the shaft; and a shank coupled to the shaft; a sleeve disposed on the shaft and configured to contact the nearest-side set screw stacked on the shaft; a first button disposed in the shank and configured to advance the sleeve distally relative to the shaft by a first increment; and a second button disposed in the shank and configured to allow the sleeve to retract proximally.

[0007] The device may include any of a variety of alternative or additional features and is considered to be within the scope of this disclosure. For example, in some embodiments, the sleeve may include a plurality of ratchet teeth. In some embodiments, the first increment may correspond to the distance between two adjacent teeth of the plurality of ratchet teeth. In some embodiments, the device may further include a stop disposed in the shank, the stop being configured to interface with the plurality of ratchet teeth to resist movement of the sleeve. In some embodiments, the stop may be a spring-biased ball. In some embodiments, the second button may be biased to contact a ratchet tooth of the plurality of ratchet teeth. And in some embodiments, the second button may allow proximal retraction of the sleeve when the bias of the second button is overcome.

[0008] In some embodiments, the device may further include a spring clip disposed around the distal end of the shaft and configured to retain a set screw thereon by an interference fit.

[0009] In some embodiments, movement of the first button may cause movement of the second button. In some embodiments, movement of the first button may cause the second button to translate distally. Additionally, in some embodiments, the first button may be biased proximally such that proximal movement of the first button causes proximal movement of the second button relative to the sleeve.

[0010] In some implementations, the outer diameter of the plurality of set screws stacked on the shaft may be substantially equal to the outer diameter of the sleeve disposed on the shaft.

[0011] In some embodiments, the sleeve may further include a retaining mechanism located on the sleeve to prevent the sleeve from ejecting from the handle. In some configurations, the retaining mechanism may be adjacent to the second button to hold the sleeve within the handle.

[0012] In some implementations, the first button may be located on the proximal end of the handle, and the second button may be located on one side of the handle.

[0013] In some implementations, either the first button or the second button may be biased.

[0014] In another aspect, a surgical method is provided that may include: delivering a first set screw to a first implantable bone anchor using an insert; actuating the insert to advance a second set screw distally relative to the axis of the insert; and using the insert to deliver the second set screw to a second implantable bone anchor.

[0015] Similar to the aforementioned apparatus, the methods disclosed herein may include any of a variety of additional or alternative steps considered within the scope of this disclosure. In some embodiments, for example, actuating the insert may include pressing down a first button disposed in the handle of the insert. Additionally, in some embodiments, actuating the insert may include advancing a sleeve disposed on the shaft distally to push the second set screw toward the distal end of the shaft.

[0016] In another aspect, a surgical method is provided, which may include: actuating a first button disposed in the handle of an insert; sliding a sleeve disposed on the shaft of the insert proximally; and advancing a plurality of set screws proximally on the distal portion of the shaft of the insert.

[0017] In some embodiments, the first button may be located on one side of the handle. And in some embodiments, the sleeve may slide to abut against the proximal sidewall of a groove formed in the handle.

[0018] Any of the features or variations described herein may be applied in a variety of different combinations to any particular aspect or implementation of this disclosure. No particular combination is explicitly described merely to avoid unnecessary length or redundancy. Attached Figure Description

[0019] The aspects and embodiments of this disclosure will be more fully understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

[0020] Figure 1 is a perspective view of one embodiment of the multi-set screw insertion device of the present disclosure, wherein a plurality of set screws are provided on the multi-set screw insertion device;

[0021] Figure 2A is an exploded perspective view of the multi-set screw insertion device in Figure 1;

[0022] Figure 2B is a cross-sectional perspective view of the multi-set screw insertion device of Figure 2A;

[0023] Figure 3 is a perspective view of the internal drive shaft of the multi-set screw insertion device of Figure 1, on which multiple set screws are provided.

[0024] Figure 4 is a cross-sectional perspective view of the handle of the multi-set screw insertion device in Figure 1;

[0025] Figure 5 is a perspective view of multiple set screws used with the multi-set screw insertion device of Figure 1;

[0026] Figure 6 is a cross-sectional perspective view of the multi-set screw insertion device of Figure 1 in the first position;

[0027] Figure 7 is a detailed sectional view of the distal end of the multi-set screw insertion device in Figure 1;

[0028] Figure 8 is a detailed sectional view of the handle of the multi-set screw insertion device in Figure 1;

[0029] Figure 9 is a perspective view of the button of the multi-set screw insertion device in Figure 1;

[0030] Figure 10 is a perspective view of the proximal end of the handle of the multi-set screw insertion device of Figure 1;

[0031] Figure 11 is a perspective view of the multi-set screw insertion device of Figure 1 in the first position;

[0032] Figure 12 is a perspective view of the multi-set screw insertion device of Figure 1 in the second position, with the button pressed down;

[0033] Figure 13 is a cross-sectional side view of the multi-set screw insertion device of Figure 1 in the first position;

[0034] Figure 14 is a cross-sectional side view of the multi-set screw insertion device of Figure 1 after the set screw has been inserted;

[0035] Figure 15 is a cross-sectional side view of the multi-set screw insertion device of Figure 1 in the second position, with the button pressed down;

[0036] Figure 16 is a cross-sectional side view of the multi-set screw inserter of Figure 1 in the third position, which is reset for set screw insertion.

[0037] Figure 17 is a cross-sectional perspective view of the multi-set screw insertion device of Figure 1, which has a final set screw installed thereon.

[0038] Figure 18 is a detailed sectional view of the distal end of the multi-set screw insertion device of Figure 17;

[0039] Figure 19A is a detailed view of one embodiment of the drive shaft and retaining feature;

[0040] Figure 19B is a detailed sectional view of the drive shaft and retaining features of Figure 19A;

[0041] Figure 20 is a detailed view of another embodiment of the drive shaft and retaining feature;

[0042] Figure 21 is a cross-sectional side view of another embodiment of the drive shaft and retaining feature;

[0043] Figure 22 is a cross-sectional side view of another embodiment of the drive shaft and retaining feature;

[0044] Figure 23 is a cross-sectional perspective view of the multi-set screw insertion device of Figure 1 in an extended configuration;

[0045] Figure 24 is a cross-sectional side view of the multi-set screw inserter of Figure 1, which has an outer shaft that pops out from it;

[0046] Figure 25 is a cross-sectional side view of the multi-set screw insertion device of Figure 1, in which the outer shaft is inserted into the shank;

[0047] Figure 26 is a cross-sectional side view of the multi-set screw inserter of Figure 1, reloaded to the first position;

[0048] Figure 27 is a perspective view of another embodiment of the handle according to the present disclosure;

[0049] Figure 28 is a detailed view of another embodiment of a multi-set screw insertion device with a pin inserted through the handle;

[0050] Figure 29 is a detailed sectional view of the multi-set screw insertion device of Figure 28;

[0051] Figure 30 is a detailed cross-sectional view of the pin that passes through the multi-set screw insertion device in Figure 28;

[0052] Figure 31 is a perspective view of another embodiment of the multi-set screw insertion device;

[0053] Figure 32 is a perspective view of the multi-set screw insertion device of Figure 31;

[0054] Figure 33 is a cross-sectional view of the multi-set screw insertion device of Figure 31;

[0055] Figure 34 is a perspective view of the driver shaft of the multi-set screw insertion device of Figure 31;

[0056] Figure 35A is a cross-sectional side view of the multi-set screw insertion device of Figure 31 in the first position;

[0057] Figure 35B is a cross-sectional side view of the multi-set screw inserter of Figure 31 after the set screw has been inserted.

[0058] Figure 35C is a cross-sectional side view of the multi-set screw insertion device of Figure 31 in the second position, wherein the button is pressed down to advance the outer sleeve;

[0059] Figure 35D is a cross-sectional side view of the multi-set screw inserter of Figure 31 in the third position, which is reset for set screw insertion.

[0060] Figure 36A is a cross-sectional side view of the multi-set screw inserter of Figure 31 in the fourth position, which has an outer shaft that pops out from it.

[0061] Figure 36B is a cross-sectional side view of the multi-set screw insertion device of Figure 31 in the fifth position, wherein the outer shaft is reintroduced into the shank.

[0062] Figure 36C is a cross-sectional side view of the multi-set screw inserter of Figure 31 reloaded to the first position;

[0063] Figure 37 is a detailed cross-sectional view of an embodiment in which multiple set screws are inserted into the handle of an instrument;

[0064] Figure 38 is a detailed sectional view of the multi-set screw insertion device of Figure 37 in the first position;

[0065] Figure 39 is a detailed sectional view of the multi-set screw insertion device of Figure 37 in the second position;

[0066] Figure 40A is a perspective view of one embodiment of a multi-set screw insertion device;

[0067] Figure 40B is an exploded perspective view of the multi-set screw insertion device of Figure 40A;

[0068] Figure 40C is a side view of the insertion instrument using the multi-set screw of Figure 40A;

[0069] Figure 40D is a detailed sectional view of the distal end of the multi-set screw insertion device of Figure 40A;

[0070] Figure 40E is a top view of the multi-set screw insertion device of Figure 40A;

[0071] Figure 40F is a cross-sectional side view of the multi-set screw insertion device of Figure 40A;

[0072] Figures 41A to 41G show the set screw insert shaft of the instrument in Figure 40A;

[0073] Figures 42A to 42D show the set screw insert shank of the device in Figure 40A;

[0074] Figures 43A to 43C show the actuator buttons of the device in Figure 40A;

[0075] Figures 44A to 44C show the distal end of the actuator button of Figure 43A;

[0076] Figures 45A to 45E show the side latch of the instrument in Figure 40A;

[0077] Figures 46A to 46C show the spring clip of the instrument in Figure 40A;

[0078] Figures 47A to 47D show the outer ratchet sleeve of the instrument in Figure 40A; and

[0079] Figure 48 shows one embodiment of a set screw for use with the multi-set screw insertion device of Figure 40A. Detailed Implementation

[0080] Certain exemplary embodiments will now be described to provide an overall understanding of the principles of structure, function, manufacture, and use of the devices, systems, and methods disclosed herein. One or more examples of these embodiments are illustrated in the accompanying drawings. The devices, systems, and methods specifically described herein and illustrated in the drawings are non-limiting embodiments. Features shown or described in one embodiment may be combined with features of other embodiments. Such modifications and variations are intended to be included within the scope of this disclosure. Furthermore, the use of linear dimensions, circular dimensions, or other dimensions in the description of the disclosed devices and methods is not intended to limit the types of shapes that may be used in conjunction with such devices and methods. Equivalents of such dimensions may be determined for different geometries, etc. Additionally, components with similar designations in the embodiments may generally have similar features. Furthermore, the size and shape of the devices and their components may depend at least on the anatomy of the subjects who will use these devices, the size and shape of the objects that will be used with these devices, and the methods and procedures for using these devices.

[0081] This disclosure relates in its entirety to a multi-set screw insertion device and method of use that addresses the challenges of existing methods. The multi-set screw insertion device disclosed herein reduces the number of times the device is passed between the surgeon and assistant while maintaining the ability to deliver set screws for attachment to spinal surgical instruments. In one embodiment, the multi-set screw insertion device may include: an inner actuator shaft on which a plurality of set screws are stacked; and an outer actuator sleeve having a ratchet portion for progressively advancing the set screws along the inner actuator shaft for insertion into bone anchors and other spinal instruments. The inner actuator shaft and outer sleeve may be received within a handle having a button for actuating the device. Actuation of the device may cause relative movement between the inner actuator shaft and the outer sleeve to sequentially eject the set screws from the device into a bone anchor receiver head or other spinal instruments.

[0082] Figures 1 through 2B illustrate one embodiment of a multi-set screw insertion device or inserter device 100. The multi-set screw insertion device 100 can be used to deliver set screws to a spinal device during procedures such as spinal surgery. The device 100 may include an inner drive shaft 102; an outer sleeve 104; and a handle 106 configured to receive the inner drive shaft 102 and the outer sleeve 104 therein. The inner drive shaft 102 may include drive features 108 for receiving a plurality of set screws 110 thereon. In some embodiments, the device 100 may include a central longitudinal axis A1 extending through the device such that axis A1 passes through one or more of the inner drive shaft 102, the outer sleeve 104, and / or the handle 106. In use, the inner drive shaft 102 may be received inside the outer sleeve 104, wherein the outer sleeve is configured to translate relative to the inner drive shaft 102. After the previous set screw is ejected from the instrument, for example, due to the insertion of the previous set screw into the spinal implementation, the translation of the outer sleeve 104 can sequentially advance the set screws 110 of the plurality of set screws 110 to the distal end 112 located on the drive feature 108 of the inner drive shaft 108.

[0083] Figures 2A and 2B specifically illustrate the assembly of the multi-set screw inserter 100. The internal drive shaft 102 may include a generally tubular body 114 having a proximal end 102p and a distal end 102d, and a central longitudinal axis A1 extending between them. The tubular body 114 may be solid, but in some embodiments, the body may be hollow, allowing an opening to extend through it. The proximal end 102p of the internal drive shaft 102 may include a mating feature 116 for coupling with a corresponding threaded hole 120 in the shank 106, such as a threaded protrusion as shown in Figure 2B, as described in more detail below with respect to Figure 4. In some embodiments, the mating feature 116 may be keyed to receive within the hole in a particular orientation, such that the internal drive shaft 102 is coupled to the shank 106 in that particular orientation.

[0084] The drive feature 108 located at the distal end 102d of the inner drive shaft 102 can be shaped to correspond to an inner opening in one of the plurality of set screws 110. As shown, the drive feature 108 can be a convex quincunx-shaped protrusion. ® A protruding portion extends along the distal portion of shaft 102, allowing a plurality of set screws 110 to be stacked on drive feature 108. The plurality of set screws 110 may include recesses shaped to correspond to drive feature 108 to allow the set screws to be secured to and rotate with drive feature 108, while also allowing proximal translation of the set screws on drive feature 108. In some embodiments, drive feature 108 may include retaining feature 118, as shown in FIG3, to prevent accidental detachment of the set screws 110 from drive feature 108. Further details of the retaining feature are discussed below.

[0085] The overall shape of the insert device 100 may resemble that of an elongated set screw driver. The outer sleeve 104 may include a generally tubular body 122 having a proximal end 104p and a distal end 104d defining a channel 124 between the two. The channel 124 may extend along a common axis of a central longitudinal axis A1 of the inner driver shaft 102, such that the central longitudinal axis A1 extends from the proximal end 104p of the outer shaft 104 to the distal end 104d. As shown, the channel 124 may be configured to receive at least a portion of the inner driver shaft 104 passing through the channel. For example, the body 122 of the outer sleeve 104 may define an inner diameter ID that is substantially the same size as or larger than the outer diameter OD of the inner driver shaft 102 to receive the inner driver shaft 102 passing through the body.

[0086] In some embodiments, the outer sleeve 104 may include a non-uniform outer diameter OD1. For example, the outer diameter OD1 of the tubular body 122 of the outer sleeve 104 may be larger in some locations than in others. In some embodiments, the outer diameter OD1 may taper along the length of the body. In some embodiments, the outer sleeve 104 may taper from a proximal end 104p toward a distal end 104d, such that the proximal end 104p engages one or more features within the handle 106 to selectively allow or prevent translation of the outer sleeve 104 relative to the handle and / or the inner drive shaft 102. As shown, the outer sleeve 104 may include a proximal head 126 having a larger outer diameter OD1 than the portion of the sleeve extending distally from the proximal head. The proximal head 126 may serve as a retaining mechanism that prevents unintentional or undesirable separation of the sleeve 104 from the handle 106. For example, the proximal head 126 may interface with a latch or button 178 to provide a stop that prevents the sleeve 104 from being completely removed from the handle 106. The stop prevents axial translation of the outer shaft 104 relative to other components of the insert device 100. Although the proximal head 126 is shown, the stop may include a ribbed surface, a protrusion, a snap-fit, or another component configured to retain the outer sleeve 104 within the handle 106.

[0087] The outer sleeve 104 may include a ratchet portion 128 formed along the tubular body 122. As shown, while the ratchet portion 128 may extend along a central segment of the outer sleeve 104, in some embodiments, the ratchet portion 128 may extend along any length of the sleeve. The ratchet portion 128 may include a series of ratchet teeth, ribs, or protrusions 130 formed along the outer surface of the outer sleeve 104. The ratchet portion 128 may engage with one or more components of the instrument 100, such as pawl 178 discussed below, for progressively advancing the outer shaft 104 relative to other components, as discussed in more detail below. The ratchet portion 128 may extend circumferentially around the tubular body 122 to allow the outer sleeve 104 to be inserted into the handle 106 in any rotational orientation. In use, the ratchet portion 128 allows the outer sleeve 104 to provide a hard stop behind the set screw, which assists the user in beginning to screw the set screw into the implant and prevents proximal movement of the set screw or outer sleeve when the user applies axial thrust to the device during insertion. Furthermore, the ratchet portion 128 can be combined with inserting a previous set screw into a spinal fastening construct such as a bone screw receiver component to facilitate advancing the next set screw toward the distal end of the actuator shaft 102.

[0088] The handle 106 may include a tubular body 132 having a central lumen 134 formed therein. The central lumen 134 may extend along the central longitudinal axis A1 of the device 100 from a distal end 106d to a proximal end 106p of the handle 106 to receive one or more of an inner actuator shaft 102 and / or an outer sleeve 104 passing through the central lumen. The central lumen may include an inner diameter ID2, which may be substantially the same as or larger than the outer diameter OD1 of the outer sleeve 104 to allow the outer sleeve to be disposed within the central lumen 134.

[0089] The central lumen 134 may include a receiving portion 136 at the proximal end 106p of the shank 106. The receiving portion 136 may extend within the central lumen 134 to receive the proximal end 102p of the inner drive shaft 102 therein. As shown in more detail in FIG4, the receiving portion 136 may include a bore 138 having a reduced diameter portion positioned along the central longitudinal axis A1 and the central lumen 134. In some embodiments, the receiving portion 136 or a segment thereof may be threaded. For example, as described above, the receiving portion 136 may include a thread 120 located on the receiving portion to allow the inner drive shaft 102 to be threadedly connected to the receiving portion. During assembly, the proximal end 102p of the inner drive shaft 102 may be inserted into the receiving portion 136, wherein a mating feature 116 is threaded into the thread 120 to couple the inner drive shaft 102 to the shank 106.

[0090] The receiving portion 136 may include a lumen 140 formed therein. For example, a thread 120 may extend through the receiving portion 136 and terminate at or near the lumen 140. The lumen 140 may receive one or more coupling features of the device 100 therein, as described in more detail below. The handle 106 may include a recess 142 formed at a proximal end 106p of the handle. For example, as shown, the receiving portion 136 may terminate distal to the proximal end 106p of the handle 106 to define the recess 142 between the two. The recess 142 may receive one or more components configured as an actuating device. For example, as shown, a button 150 may be disposed within the handle 106 to control the advancement of the outer sleeve 104 to push the set screw 110 distally.

[0091] The handle 106 may be made of a variety of materials, including any of various plastics, ceramics, or metals. In some embodiments, the handle 106 may include an overlay injection molded part of a variety of materials, such as a silicone overlay injection molded part formed on another underlying material. The handle 106 may include a series of openings 148 at the distal end 106d of the handle to allow components of the instrument 100 to be operated facilitating its use. The series of openings 148 may extend laterally into the central lumen 134 to communicate with the outer sleeve 104 disposed in the central lumen. The series of openings 148 will be discussed in more detail below with reference to Figures 11 and 12.

[0092] Figure 5 illustrates a plurality of set screws 110 that can be used with the multi-set screw inserter 100 of this disclosure. As shown, each of the plurality of set screws 100 may include a concave drive feature or through-hole 144 that completely cuts through the set screw. The set screws 110 may be stacked one on top of the other such that the axis A through the set screw is aligned with the central longitudinal axis A1. The concave drive feature 144 may be configured to pass through a convex drive feature 108 that receives the inner drive shaft 102 to arrange the stack of set screws 110 along the inner drive shaft. For example, the through-hole 144 may include a geometry complementary to the drive feature 108 to allow the set screws 110 to stack on the insert shaft 102 and be rotatably driven by the insert shaft 102 when the inserter device 100 is rotated. The size of the through-hole 144 may be set to allow each of these set screws 110 to translate axially along the drive feature 108 when the outer sleeve 104 is advanced relative to the inner drive shaft 102. In addition, each set screw may have an outer diameter OD2, and in some embodiments, the outer sleeve 104 may be no larger than the outer diameter OD2 of the set screw 100.

[0093] Figures 6 through 8 illustrate the insert device in more detail. As shown, the insert device 100, when positioned initially, includes an inner drive shaft 102 disposed within a channel 124 of an outer sleeve 104, with two components received within a central cavity 134 of a handle 106. Specifically, as described above, a mating feature 116 of the inner drive shaft 102 can be screwed into a thread 120 within the receiving portion 136, while the proximal end 104p of the outer sleeve 104 may abut the receiving portion 136. A plurality of set screws 110 may be disposed on a drive feature 108 of the inner drive shaft 102 distal to the outer sleeve 104.

[0094] Figure 7 illustrates in more detail the relationship between the stack of set screws 110 and the inner drive shaft 102. As described above, the inner drive shaft 102 may include a retaining feature 118, such as a spring clip or spring ring, that engages the distal end 112 of the drive feature 108. As shown in Figure 7, the spring clip 118 located at the distal end of the drive feature 108 provides an interference fit between the spring clip and the set screw 110, thereby limiting unwanted distal translation between the set screw and the drive feature.

[0095] Figure 8 illustrates the interaction of the inner drive shaft 102, outer sleeve 104, and handle 106 of the insert device 100 in the aforementioned initial position. The outer shaft 104 is received within a central lumen 134, while the proximal head 126 abuts the receiving portion 136. A bore 140 may receive a biasing element 152, such as a coil spring, configured to compress and extend in the axial direction upon engagement with one or more components of the device 100. For example, as shown, the biasing element 152 may be disposed between the receiving portion 136 and a button 150. The biasing element 152 may proximally bias the button 150 such that the button 150 extends at least partially out of the recess 142.

[0096] Figure 9 shows the button 150 in more detail. As shown, the button 150 includes a proximal head 154 and a distal body 156 extending from the proximal head. The proximal head 154 may include an outer diameter (not shown) that is substantially the same as or smaller than the diameter of the recess 142 to allow the head to be positioned within the recess 142. The head 154 may include a distally facing surface 158 for engaging a portion of a biasing element 152 to compress the biasing element when the button 150 is actuated. In some embodiments, the proximal head 154 may include a hole 160 formed therein.

[0097] The distal body 156 may include a sidewall 162 extending from the proximal head 154 and along the interior portion of the inserter instrument handle 106. For example, the handle 106 may include a lumen 164 formed therein to allow the distal body 156 to pass through it. In some embodiments, the lumen 164 may be separate from the central lumen 134. As shown in FIG8, the lumen 164 may terminate within the interior of the handle 106, for example, distal to the receiving portion 136. However, in some embodiments, a second lumen 164 may extend through the distal end of the handle 106.

[0098] The distal body 156 may include one or more access points in its sidewall 162. These access points may be aligned with one or more openings 148 in the handle 106 to facilitate advance or rotation of the outer sleeve 104 relative to the handle. For example, the distal body 156 may include a cutout 166 formed therein, which forms a pair of flanges 168, 170. The cutout 166 may be aligned with one or more openings 148 in the handle 106, as described above, to allow another component to extend simultaneously through the handle 106 and the distal body 156 and engage the outer sleeve 104, as discussed further below. As shown, one or more lateral openings 172, 174 may be formed in each of the flanges 168, 170 to facilitate coupling between components disposed within the cutout 166.

[0099] Access points may be formed in the outer surface of sidewall 162. For example, the top surface of sidewall 162 shown in FIG. 9 may include a recess 176 for receiving a biasing element 177 (such as a coil spring or other biasing element). The biasing element 177 may, for example, bias another component disposed in the cutout 166 such that a portion of the other component extends into the central lumen 134 to engage the outer shaft 104, as described in more detail below. One embodiment of such a component may be a pawl, latch, or button 178 (see FIG. 8) extending into the central lumen 134 to engage the outer shaft 104. For example, feature 178 may extend from a distal end 178d to a proximal end 178p, wherein the distal end 178d has an engagement surface 180 thereon. Engagement surface 180 may extend radially inward from the cutout 166 of button 150 and the opening 148 of handle 106 to engage the ratchet portion 128 of outer sleeve 104. Pawl 178 can be coupled to button 150 via pin 182 received in openings 172, 174 of flanges 168, 170. Pin 182 allows pawl 178 to pivot about the axis of pin 182. Proximal end 178p of pawl 178 may include a recess to receive one end of biasing element 177. Biasing element 177 can thus radially push the proximal end of pawl 178p radially outward and radially push the distal end of pawl 178d radially inward toward outer sleeve 104 and ratchet portion 128.

[0100] Sidewall 162 may include a slot 184 configured to receive pin 186. The pin may be anchored within a hole formed in the sidewall of handle 106 such that the pin is not axially translated relative to the handle. The slot may extend axially along the distal body 156 to allow button 150 to translate axially between a proximal and distal position, as defined by the length of slot 184. Movement of slot 184 relative to pin 186 may limit translation of the distal body 156 and button 150 during actuation of insert device 100. For example, actuation of button 150 may advance distal body 156 until pin 186 reaches the proximal end of slot 184. Retraction of button 150 may similarly move pin 186 to the distal end of slot 184, and interference between the pin and the end of slot prevents further movement of button 150.

[0101] The insert device 100 may also include a stop 188, such as a spring plunger or ball stop, received in the handle 106 through an opening 149. The stop 188, shown as a ball bearing radially inwardly biased by a helical spring, engages the ratchet portion 128 to resist movement of the outer sleeve 104 relative to the handle 106. This prevents undesirable proximal or distal movement of the outer sleeve 104 relative to the handle 106, and specifically prevents proximal movement of the outer sleeve 104 together with the button 150 when the button retracts proximally after actuation. It should be understood that in some embodiments, a leaf spring, a cantilever deformable element, or other components may be used to replace the spring plunger shown in the device 100.

[0102] Figures 11 through 16 illustrate the actuation of the multi-set screw inserter 100 in more detail. As shown in Figure 11, the button 150 of the multi-set screw inserter 100 protrudes proximally from the proximal end of the shank 106 in an initial position. Once actuated, as shown in Figure 12, the resistance of the biasing element 152 is overcome, and the button 150 moves distally into the recess 142 of the shank 106.

[0103] Figures 13 through 16 illustrate the sequence of inserting set screws using a multi-set screw inserter 100 during the procedure. Similar to Figure 11, Figure 13 shows the multi-set screw inserter 100 in its initial position, with a plurality of set screws 110 stacked on the distal portion of the inner drive shaft 102. In this configuration, the first button 150 is biased to the proximal position, and the pawl or second button 178 is biased to a position where the distal end engagement surface 180 of the pawl or second button is received within the distal recess 130 of the ratchet portion 128 of the outer sleeve 104. Proximal movement of the outer sleeve 104 relative to the drive shaft 102 and the handle 106 is prevented by the interaction between the proximal end of the outer sleeve and the handle receiving portion 136, and by the interaction between the ratchet portion 128 and the pawl 178 (which is subsequently limited by the interaction of the pin 186 and the slot 184). Therefore, the user can push the distal set screw into a receiving member, such as a bone anchor, to couple the set screw to the bone anchor. Axial and rotational forces can be transferred to the distal set screw to facilitate its insertion. Once the set screw 110 is coupled to the bone anchor, the multi-set screw insertion device 100 can retract proximally, allowing the distal set screw to overcome any resistance from the retaining feature 118 and disengage from the actuator shaft 102. Alternatively or otherwise, the user can press button 150 to advance the outer sleeve 104 relative to the actuator shaft 102, as described below, to assist in ejecting the distal set screw from the device.

[0104] As shown in Figure 14, once the set screw is coupled to the bone anchor and the instrument retracts proximally to decouple the distal set screw from the instrument, the drive feature 108 and distal end 112 of the internal actuator shaft 102 are exposed. To advance the stack of set screws 110 distally toward the end 112, button 150 can be actuated, as shown in Figure 15. Actuation of button 150 overcomes the force of biasing element 152, and distal advancement of button 150 includes advancement of distal body 156 relative to handle 106 within lumen 164. Advancement of distal body 156 includes advancement of pawl 178. Pawl 178, engaging the distal recess 130 of ratchet portion 128, together with pawl and button 150, pushes the outer sleeve 104 distally. Actuation of button also provides sufficient force to overcome the resistance of stop 188 against movement of outer sleeve 104.

[0105] When pin 186 abuts the proximal end of slot 174 and the distal surface 158 of button 150 reaches the proximal end of recess 142, distal advance of outer sleeve 104 terminates. In this position, the new distal set screw can be positioned near the distal end 112 of drive shaft 108. In this orientation, as shown in FIG15, stop 188 can engage the second recess 131 of ratchet portion 128 to again provide resistance against movement of outer sleeve 104. Button 150 can then be released, and biasing element 152 can return button 150 to its proximal position. This, in turn, pushes pawl 178 proximally. The resistance provided by the stop 188 overcomes the friction between the pawl 178 and the ratchet portion 128 of the outer sleeve 104, keeping the outer sleeve stationary relative to the handle 106, and the pawl 178 entering the second groove 131 of the ratchet portion 128 as it moves proximally relative to the handle 106 and the outer sleeve 104. Without the stop 188, the outer sleeve 104 may retract proximally together with the pawl or button 178 due to the friction between them. Once the button 150 returns to its proximal initial orientation, the set screw insertion process can be repeated until the stack of set screws 110 along the inner drive shaft 102 has been fully inserted into the desired positions of these set screws and ejected from the insertion device.

[0106] Figure 17 illustrates an insert device 100 in which a single set screw is retained after a plurality of set screws 110 have been inserted. As shown, a pawl or second button 178 and a stop 188 engage with the nearest-side recess of the ratchet portion 128 of the outer sleeve 104. Figure 18 shows a detailed view of the distal end of the device 100, in which the set screw engages with a retaining feature 118 to prevent displacement of the set screw. The retaining feature 118 may include a spring clip or spring ring surrounding the distal end 112 and providing a radially outward interference fit with a recessed drive groove or hole formed in the set screw 110. The spring clip 118 may deform to reduce its outer diameter, thereby allowing sufficient force to be applied from the outer sleeve 104 to push the set screw 110 over the clip and eject the set screw from the device 100.

[0107] Alternative embodiments of the drive feature and retaining feature 118 formed on the distal portion of the drive shaft 108 are shown in Figures 19 through 21. While spring clips or spring rings have been discussed above, other embodiments are possible. As shown in these figures, the retaining feature 218 may include opposing ball stops extending laterally from the distal end of the drive shaft 202. The opposing ball stops may be biased by a spring 220 or another biasing element. As shown in Figures 19A and 19B, the drive shaft 202 may include a protruding distal end 212 at the distal end of the drive feature 208. The protruding distal end 212 may have a cylindrical profile with a diameter substantially equal to or smaller than the small diameter of the drive feature 208, and may include chamfered or tapered edges to facilitate insertion of the drive shaft and set screw disposed therearound into, for example, a bone screw receiver head. In other embodiments and as shown in FIG20, the drive shaft 302 may include a drive feature 308 extending to the distal end of the drive shaft, and a retaining feature 318 may be incorporated into the drive feature without a protruding distal end having a different shape from the drive feature.

[0108] Figures 21 and 22 illustrate another embodiment of a retaining feature 408 that can be incorporated into a drive shaft 402. The retaining feature 408 may include a leaf spring or other resilient element disposed within a recess formed in the drive shaft 402. In the embodiment of Figure 21, the spring 408 is similar to a fork or U-shaped member having a proximal end anchored within the shaft 402 and a distal end projecting through an opposing opening formed in the outer surface of the shaft. Similar to the other retaining feature embodiments described above, the projecting distal end of the leaf spring 408 may be configured to retain a set screw to the drive shaft via an interference fit. Figure 22 illustrates an embodiment in which a more linear spring element 508 provides a single protrusion from a single opening formed in the outer surface of the shaft 502. In an embodiment where the resilient element is anchored within the drive shaft, the shaft may be configured as two parts, such as a distal part 402d and a proximal part 402p as shown in FIG. 21, such that the resilient element 408 can be positioned within a groove formed in each part, and these parts may subsequently be coupled, for example, at a joint 403, by adhesive, welding, mechanical reinforcement, etc. Any of the above-described drive feature embodiments and retaining feature embodiments may be used in conjunction with any of the embodiments of the multi-set screw insertion device disclosed herein.

[0109] Furthermore, various other components of the multi-set screw insert device can be configured to provide a different interaction than the retaining feature used to hold the set screw in case of accidental ejection from the device. For example, in some embodiments, the device can be configured to position the set screw exactly proximal to the retaining feature, such that the distally facing surface of the distal set screw abuts a portion of the retaining feature. However, in other embodiments, the device can be configured such that the distal set screw is positioned above the retaining feature, such that the radially inward-facing surface of the set screw abuts a radially outward-facing portion of the retaining feature. Different configurations can be achieved by tuning one or more of the lengths of the outer sleeve, inner shaft, ratchet portion, and first button to achieve the desired spacing and advance. Choosing one configuration or another can produce different tactile feedback to the user. For example, in an embodiment where the distal set screws are stacked proximal to the retaining feature, during actuation of the first button, the user can feel or overcome a resistance when advancing the distal set screw past the retaining feature (first resistance) and only advancing the next set screw to abut the retaining feature. In another embodiment, in which the distal set screw is positioned above the retaining feature, during actuation of the first button, the user can feel or overcome two resistances: the distal set screw ejects from the retaining feature (first resistance) and the next set screw is pushed past the top of the retaining feature (second resistance). Any of the various embodiments disclosed herein can be configured to operate in any manner.

[0110] As described above, the outer sleeve 104 may include a proximal head 126, which serves as a retaining mechanism to prevent the outer sleeve 104 from accidentally separating from the device after all set screws have popped out. Figure 23 illustrates the proximal head 126 for preventing the outer shaft 104 from falling distally from the central cavity 134 and disengaging from the inner shaft 102. To further explain, once the pawl or second button 178 is no longer engaged with the ratchet portion 128 of the outer sleeve 104, distal advance of the outer sleeve can continue substantially uninterrupted until the pawl 178 engages the proximal head 126, which in some embodiments may have an outer diameter substantially the same as or greater than the outer diameter of the ratchet portion 128. Friction between the engagement surface 180 at the distal end 178d of the pawl and the proximal head 126 prevents the outer sleeve 104 from separating from the central cavity 134. To separate the outer sleeve 104 from the rest of the instrument, the user can press down the proximal end 178p of the pawl or second button 178 to retract the distal end 178d radially outward and provide clearance for the proximal head 126 to exit distally from the lumen 134 of the handle 106. In some embodiments, the proximal head 126 may include a distally facing surface with a tapering diameter to provide an insertion end that allows the user to remove the outer sleeve 104 by applying sufficient force without separately pressing the second button 178.

[0111] Figures 24 through 26 illustrate the process of at least partially assembling the instrument and loading the set screw. In Figure 24, the outer sleeve 104 is shown as part of the assembly to the remainder of the instrument 100. The outer sleeve 104 can be inserted proximally over the drive shaft 102, and upon entering the lumen 134 of the handle 106, the distal end of the outer sleeve may abut against the distal end 178d of the pawl or second button 178. In some embodiments, the proximal end 178p of the pawl or second button 178 can be pressed to compress the spring 177, causing the distal end 178d to pivot radially outward and allowing the outer sleeve 104 to be further inserted into the central lumen 134, as shown in Figure 25. In some embodiments, the proximal end of the outer sleeve 104 and the head 126 formed on the outer sleeve may include a proximal-facing surface with a tapered diameter to provide an insertion end that allows the user to insert the outer sleeve 104 by applying sufficient force without separately pressing the second button 178. Once the outer sleeve 104 is fully inserted into the handle 106 so that the proximal head 126 passes the pawl or second button 178, the outer sleeve can continue until the ratchet portion 128 reaches the pawl. The proximal end 178p of the pawl or second button 178 can then be pressed down to allow the outer sleeve to continue moving proximally until the pawl reaches the distal end of the ratchet portion. At this point, the distal end of the drive shaft 102 will be exposed beyond the distal end of the outer sleeve 104, and a plurality of set screws can be inserted over the distal end of the drive shaft and stacked along the drive feature 108, as shown in FIG26.

[0112] Additional details and alternative embodiments of the device are shown in Figures 27 to 48. For example, Figure 27 shows a handle 206 that may include a silicone-coated molded clamping member 207. Any of a variety of materials may be used to form the handle, including metals, polymers, etc. Clamping reinforcement features such as ribs, embossing, or other textures may be provided on the outer surface of the handle.

[0113] Figures 28 to 30 illustrate an embodiment in which the handle 606 includes a hole formed in the handle to receive a pin 608 that helps secure the drive shaft 602 to the handle. As shown, the pin 608 may extend laterally through the handle 606 of the insert instrument 600 and through the inner drive shaft 602 to prevent unwanted rotation of the drive shaft relative to the handle during use. In embodiments in which the drive shaft 602 is threadedly coupled to the handle 606, undesirable relative rotation between these components during use can cause separation or adjustment of the relative positioning. The use of the pin 608, configured to pass through a coaxial lateral hole formed in the handle 606 and the shaft 602, prevents any such relative rotation between these components.

[0114] Figure 31 illustrates another embodiment of the multi-set screw insertion device 500. The overall shape of the device 500 may resemble that of an intermediate set screw driver. The insert 500 may include an inner driver shaft 502 having a relatively long convex drive feature at its distal end and a spring clip retention mechanism at its distal end 512. A plurality of set screws 510, having concave drive features that completely cut through them, may be stacked on the driver along the axis of the concave drive features. Stacking the set screws 510 in this manner allows the diameter of the device 500 at its distal end to remain no greater than the outer diameter OD4 of the set screw, thereby improving device compatibility without increasing the device size. A ratchet sleeve 504 may be advanced over the inner driver shaft 502 to move the next set screw to the retention feature at the distal end 512 of the driver after the previous set screw has been inserted. The ratchet feature may provide a hard stop behind the set screw, which assists the user in initiating screwing into the implant. The proximal handle 506 may have a sufficiently small diameter to limit the amount of torque applied by the user and may include two buttons. A first button at the proximal end can be pressed to advance the outer sleeve 504 and the set screw 510. A second button on one side of the handle 506 can be pressed to return the outer sleeve 504 proximally and reload the instrument. When the proximal button is released to allow the ratchet mechanism to advance, a retaining mechanism on the handle can temporarily hold the outer sleeve in place.

[0115] Figure 32 shows an alternative view of the multi-set screw insertion device 500. As described above, the device 500 can reduce the time and delivery required to install multiple set screws when assembling a spinal fastening construct, which can be a significant saving in long deformity correction cases where the construct spans multiple vertebral levels and includes multiple terminations or fastening points between the rod or other spinal fastening element and the implanted bone anchor. The relatively thin cylindrical shank 506 prevents the application of large amounts of torque to the set screws, and the reduced-diameter distal portion allows for delivery of the set screws via the device, such as an extension tube coupled to the implanted bone anchor.

[0116] The aforementioned features of the insert, also shown in Figure 32, include a button 550 on the proximal end that controls the advance of the ratchet outer sleeve 504 over the inner sleeve to push the loaded set screw 510 distally, and prepares the second set screw after the first set screw has been delivered. A second button 578 on one side of the shank 506 is also shown, which allows proximal movement of the outer sleeve 504 to reload the device with an additional set screw. Finally, the figure shows a plurality of set screws 510 stacked on the inner shaft at the distal end of the insert 500.

[0117] Figure 33 shows a partial perspective view of the insert 500 of Figure 32 to illustrate the operation and internal mechanisms of the insert in more detail. Starting at the distal end of the device, the inner shaft 502 includes an extended distal portion with a actuator end geometry 512 to allow multiple set screws to be stacked on top of the end. As shown in Figure 34, a spring clip 518 is present at the distal end of the actuator to provide soft set screw retention due to the interference between the spring clip 518 and the set screw 510. At the proximal end, a spring or other biasing element 552 pushes a button 550 proximally to return the button after the user presses it to advance the outer sleeve 504. The proximal end button 550 interfaces with a side button 578 to transfer load from the proximal button 550 to the outer sleeve 504. A spring plunger 588 prevents the ratchet outer sleeve 504 from following the side button during the return stroke of the side button 578 and the proximal button 550.

[0118] Figures 35A to 35D illustrate the set screw insertion process in cross-sectional views. The user first inserts the distal set screw into the receiver head or tulip-shaped part of the implantable bone anchor. The user then rotates the insert 500 to screw the set screw into the threaded portion of the bone anchor receiver head. The user then pulls the insert proximally to disengage it from the implantable set screw. The force of the pull and the fixed thread position of the set screw in the receiver head cause the set screw to overcome the distal spring clip and disengage from the insert, as shown in Figure 35B. The user can then press the proximal button 550 to advance the side button 578 and the outer ratchet sleeve 504 relative to the inner shaft 502, and push the stacked set screws distally until the distal set screw approaches the distal end of the insert 500 and stops due to interference with the spring clip, as shown in Figure 35C. As the ratchet sleeve 504 is advanced distally, the spring plunger 588 rotates from the first stop to the adjacent stop on the sleeve 504. As shown in Figure 35D, when the proximal button 440 is released and travels back to its initial position with the side button 578, the spring plunger 588 provides sufficient holding force to temporarily hold the sleeve 504 in its initial position, in which the buttons can be advanced again after another set screw is delivered.

[0119] Figures 36A to 36C illustrate the set screw reloading process in cross-sectional views. As shown in Figure 36A, after all set screws have been delivered, the ratchet sleeve 504 is in its most distal position. To reload, the user can press and hold the recessed side button 578, as shown in Figure 36B. This releases the ratchet sleeve 504 proximally when sufficient force is applied to overcome the spring plunger holding force, as shown in Figure 36C. Additional set screws 510 can then be loaded onto the distal drive end portion and stacked together, as shown in Figure 36C. Once the recessed side button 578 is released, it again engages with one of the ratchet teeth of the sleeve 504 to hold the sleeve in position and control the advance of the sleeve 504 when the proximity button is pressed.

[0120] Figures 37 to 39 show cross-sectional views of another embodiment 700 having a side button or latch 778 extending beyond the handle. Specifically, Figures 38 and 39 show the relative positions of the spring plunger / ball stop 788 when the outer sleeve 704 is in the first position and after the outer sleeve 704 has been advanced to deliver a new set screw.

[0121] Figures 40A to 48 show additional views of embodiments of the multi-set screw inserter. More specifically, Figures 40A to 40F show various views of one embodiment of the multi-set screw inserter 800, including exploded views showing: an outer sleeve 804, an insert shaft 802, a shank 806, a tenon 808 for securing the insert shaft 802 to the shank 806, a side latch 878, a bias spring 877 and a pivot pin 882 for the side latch 878, a proximal actuator button 850, and a bias spring 852 for the actuator button.

[0122] Figures 41A to 41G show various views of the set screw insert shaft 802, including the insert shaft having a drive end geometry 854 and a groove 856 to receive the distal portion of the spring clip.

[0123] Figures 42A to 42D show various views of the set screw insert shank 806, including a cavity 858 for receiving the insert shaft, a ratchet sleeve, a proximal button, and a side latching component.

[0124] Figures 43A to 43C show various views of the actuator button 850, including the proximal button surface 860 contacted by the user and the distal extension 862 interfacing with the side latch or second button 878. Figures 44A to 44C show various detailed views of the distal end of the actuator button 850 interfacing with the side latch, including a cutout 864 in which a protruding flange 866 forms holes 868 for receiving pins 882 to couple the side latch or second button 878 to the distal extension 862. Also shown is a recess 870 for receiving a bias spring 877 and a portion of a slot 872 for receiving a tenon 808 to limit the range of motion of the button 850 relative to the handle 806.

[0125] Figures 45A to 45E show various views of the side latch 878, including the proximal end 878p of the side latch having a groove 874 to receive the bias spring 877, the distal end 878d of the side latch, and the hole 876 for receiving the pin 882.

[0126] Figures 46A to 46C show various views of the spring clip 818 that holds the set screw on the insert shaft by an interference fit.

[0127] Figures 47A to 47D show various views of the outer ratchet sleeve 804, including a proximal portion having ratchet teeth 828 that interface with the side latch 878. It should be noted that in this embodiment, the ratchet teeth 828 are formed on only a portion of the outer circumference of the sleeve 804. In other embodiments, as disclosed above, the ratchet teeth 828 may be formed around the entire circumference of the outer sleeve 804. Additionally, in some embodiments, a first set of ratchet teeth or other surface features may be formed on one side of the outer sleeve, and a second set of ratchet teeth or other surface features may be formed on the other side of the outer sleeve, for example, to provide different surface features for interaction with each of the second button and the stop / spring plunger.

[0128] Figure 48 illustrates one embodiment of a set screw 810 for use with a multi-set screw insertion device 800. The set screw 810 may include a through-hole 811 formed therein, the through-hole having a geometry complementary to the distal portion 854 of the insert shaft to allow the set screws to stack on the insert shaft 802 and be driven by the insert shaft 802 during rotation of the insert 800. The set screw 810 may also include threads 813 formed on the outer surface of the set screw, these threads intersecting with threads formed on, for example, the inner surface of a bone screw receiver head during insertion of the set screw using the device 800.

[0129] The instruments disclosed herein may be constructed from any of a variety of known materials. Exemplary materials include those suitable for surgical applications, including metals (such as stainless steel, titanium, nickel, cobalt-chromium, or alloys and combinations thereof), polymers (such as PEEK, ceramics, carbon fiber), etc.

[0130] The devices and methods disclosed herein can be used in minimally invasive and / or open surgical procedures. Although the devices and methods disclosed herein are generally described in the context of surgery on human patients, it should be understood that the methods and devices disclosed herein can be used in any of a variety of surgical procedures on any human or animal subject, or in non-surgical procedures.

[0131] The device disclosed herein may be designed for single-use disposal or for multiple-use applications. However, in either case, the device can be repaired and reused after at least one use. Repair may include any combination of disassembling the device, subsequently cleaning or replacing specific parts, and subsequent reassembly steps. Specifically, the device is detachable, and any number of specific parts or components of the device can be selectively replaced or removed in any combination. After cleaning and / or replacing specific parts, the device can be reassembled for subsequent use at a repair facility or by a surgical team just before surgery. Repair of the device can be performed using various techniques for disassembly, cleaning / replacement, and reassembly. The use of such techniques and the resulting repaired device are within the scope of this application.

[0132] The device described herein can be processed before use in surgical procedures. First, new or used instruments are obtained and cleaned as needed. The instruments can then be sterilized. In one sterilization technique, the instrument can be placed in a closed, sealed container (such as a plastic or TYVEK bag). The container and its contents can then be placed in a radiation field that can penetrate the container, such as gamma radiation, X-rays, or high-energy electrons. The radiation kills bacteria on the instrument and in the container. The sterilized instrument can then be stored in a sterile container. Sealing the container keeps the instrument sterile until it is opened in a medical facility. Other forms of sterilization are also possible. This can include beta radiation or other forms of radiation, ethylene oxide, steam, or a liquid bath (e.g., cold immersion). Due to factors such as the materials used and the presence of electronic components, certain forms of sterilization may be better suited for use in conjunction with different parts of the device.

[0133] Further features and advantages based on the above embodiments are possible and fall within the scope of this disclosure. Therefore, this disclosure is not limited to what has been specifically shown and described. All applications and references cited herein are incorporated by full reference unless any definition, subject matter waives or denies the claims, and unless the incorporated material is inconsistent with the expression disclosed herein, in which case the language of this disclosure shall prevail.

[0134] Examples of the above implementation scheme may include the following:

[0135] Technical Solution 1. A surgical instrument, comprising:

[0136] A shaft having a distal portion configured to drive set screws and to house a plurality of set screws stacked abutting against each other on the shaft;

[0137] A handle, which is coupled to the shaft;

[0138] A sleeve, which is disposed on the shaft and configured to contact the nearest side set screws stacked on the shaft;

[0139] A first button, disposed in the handle and configured to advance the sleeve distally relative to the axis by a first increment; and

[0140] A second button is disposed in the handle and configured to allow the sleeve to retract proximally.

[0141] Technical Solution 2. The device according to Technical Solution 1, wherein the sleeve includes a plurality of ratchet teeth.

[0142] Technical Solution 3. The device according to Technical Solution 2, wherein the first increment corresponds to the distance between two adjacent teeth among the plurality of ratchet teeth.

[0143] Technical Solution 4. The device according to Technical Solution 2 further includes: a stopper disposed in the handle, the stopper being configured to interface with the plurality of ratchet teeth to resist movement of the sleeve.

[0144] Technical Solution 5. The device according to Technical Solution 4, wherein the stopper is a spring-biased ball.

[0145] Technical Solution 6. The apparatus according to Technical Solution 2, wherein the second button is biased to contact a ratchet tooth among the plurality of ratchet teeth.

[0146] Technical Solution 7. The device according to Technical Solution 6, wherein when the bias of the second button is overcome, the second button allows proximal retraction of the sleeve.

[0147] Technical Solution 8. The device according to any one of technical solutions 1 to 7 further includes: a spring clip disposed around the distal end of the shaft and configured to retain a set screw thereon by an interference fit.

[0148] Technical Solution 9. The apparatus according to any one of technical solutions 1 to 8, wherein movement of the first button causes movement of the second button.

[0149] Technical Solution 10. The apparatus according to Technical Solution 9, wherein the movement of the first button causes the second button to translate distally.

[0150] Technical Solution 11. The device according to Technical Solution 10, wherein the first button is biased proximally such that proximal movement of the first button causes proximal movement of the second button relative to the sleeve.

[0151] Technical Solution 12. The device according to any one of technical solutions 1 to 11, wherein the outer diameter of the plurality of set screws stacked on the shaft is substantially equal to the outer diameter of the sleeve disposed on the shaft.

[0152] Technical Solution 13. The device according to any one of technical solutions 1 to 12, wherein the sleeve further includes a retaining mechanism located on the sleeve for preventing the sleeve from ejecting from the handle.

[0153] Technical Solution 14. The device according to Technical Solution 13, wherein the retaining mechanism is adjacent to the second button to retain the sleeve within the handle.

[0154] Technical Solution 15. The device according to any one of technical solutions 1 to 14, wherein the first button is disposed on the proximal end of the handle, and the second button is disposed on one side of the handle.

[0155] Technical Solution 16. The device according to any one of technical solutions 1 to 15, wherein the first button is biased.

[0156] Technical Solution 17. The device according to any one of technical solutions 1 to 16, wherein the second button is biased.

[0157] Technical Solution 18. A surgical method, comprising:

[0158] The first set screw is delivered to the first implanted bone anchor using an inserter;

[0159] Actuate the insert to advance the second set screw distally relative to the axis of the insert; and

[0160] The second set screw is delivered to the second implantable bone anchor using the insert.

[0161] Technical Solution 19. The method according to Technical Solution 18, wherein actuating the insert includes pressing down a first button disposed in the handle of the insert.

[0162] Technical Solution 20. The method according to any one of Technical Solutions 18 to 19, wherein actuating the insert comprises advancing a sleeve disposed on the shaft distally to push the second set screw toward the distal end of the shaft.

[0163] Technical Solution 21. A surgical method, comprising:

[0164] The actuation is provided by the first button located in the handle of the insert;

[0165] Slide the sleeve disposed on the shaft of the insert toward the proximal side; and

[0166] Multiple set screws are advanced proximally onto the distal portion of the shaft of the insert.

[0167] Technical Solution 22. The method according to Technical Solution 21, wherein the first button is disposed on one side of the handle.

[0168] Technical Solution 23. The method according to any one of Technical Solutions 21 to 22, wherein the sleeve slides to abut the proximal sidewall of the groove formed in the shank.

Claims

1. A surgical instrument, comprising: A shaft having a distal portion configured to drive set screws and to house a plurality of set screws stacked abutting against each other on the shaft; A shank coupled to the shaft; a sleeve disposed on the shaft and configured to contact the nearest side set screws stacked on the shaft. A first button is disposed in the handle and configured to advance the sleeve distally relative to the axis by a first increment; A second button, which is disposed in the handle and configured to allow the sleeve to retract proximally.

2. The device according to claim 1, wherein the sleeve comprises a plurality of ratchet teeth.

3. The device according to claim 2, wherein the first increment corresponds to the distance between two adjacent teeth in the plurality of ratchet teeth.

4. The device according to claim 2, further comprising: A stopper is disposed in the shank and is configured to interface with the plurality of ratchet teeth to resist movement of the sleeve.

5. The device according to claim 4, wherein the stop is a spring-biased ball.

6. The apparatus of claim 2, wherein the second button is biased to contact a ratchet tooth among the plurality of ratchet teeth.

7. The device of claim 6, wherein the second button allows proximal retraction of the sleeve when the bias of the second button is overcome.

8. The apparatus according to claim 1, further comprising: A spring clip is disposed around the distal end of the shaft and configured to retain a set screw thereon by an interference fit.

9. The apparatus of claim 1, wherein movement of the first button causes the second button to translate distally.

10. The device of claim 9, wherein the first button is biased proximally such that proximal movement of the first button causes proximal movement of the second button relative to the sleeve.

11. The device of claim 1, wherein the outer diameter of the plurality of set screws stacked on the shaft is substantially equal to the outer diameter of the sleeve disposed on the shaft.

12. The device of claim 1, wherein the sleeve further comprises a retaining mechanism located on the sleeve to prevent the sleeve from ejecting from the handle.

13. The device of claim 12, wherein the retaining mechanism is adjacent to the second button to retain the sleeve within the handle.

14. The device according to claim 1, wherein the first button is disposed on the proximal end of the handle, and the second button is disposed on one side of the handle.

Images