SYSTEMS AND METHODS FOR PROVIDING ACCESS TO WITHIN BONY ANATOMY

Systems and methods for providing access to within a vertebral body. A stylet is removably disposed within a reamer, and the reamer is removably disposed within a working cannula. A tip of the stylet is positioned distal to a reamer head with a stylet hub being positioned proximal to a reamer hub. The reamer hub may include indicia configured to be aligned with the stylet hub to indicate a distance by which the tip is positioned beyond a distal end of the reamer. Complementary coupling features on the reamer hub and the stylet hub are configured to facilitate the workflow and provide mechanical advantage during removal of the stylet from the reamer. The system may include a spacer device configured to be positioned between the reamer hub and the stylet hub. The spacer device may be coupled to a stylet shaft of the stylet.

BACKGROUND

A common source of back pain is a vertebral compression fracture in which a weakened or injured vertebral body loses height or collapses. The weakening of the vertebral body may be due to acute injury or, more often, degenerative changes such as osteoporosis.

A manner of restoring height of the vertebral body includes deploying an implant within the vertebral body. One exemplary implant is sold under the tradename SpineJack by Stryker Corporation (Kalamazoo, Mich.) and disclosed in commonly-owned U.S. Pat. No. 8,986,386, issued Mar. 24, 2015, the entire contents being hereby incorporated by reference. Owing to the expandable nature of the SpineJack device, for example, the size of the implant may require achieving ten gauge or larger access through one or both pedicles of the vertebral body. Doing so may require several separate instruments that are individually and sequentially deployed according to a several step workflow. Select steps of existing systems may include inserting an access cannula, removing a trocar from the access cannula, directing a stylet through the access cannula, decoupling a stylet hub from a stylet shaft, removing the access cannula from over the stylet shaft, directing a reamer over the stylet shaft, removing the stylet shaft, and removing the reamer. Each separate instrument and each workflow step introduce the possibility of inaccuracies or user error, and consume valuable time in which the patient is under anesthesia.

Accordingly, there is a need for systems and methods for providing access to within the bony anatomy, such as the vertebral body, in an intuitive manner that reduces the number of steps and requires less instrumentation.

SUMMARY

The present disclosure is directed to improved systems and methods for providing access to within bony anatomy, such as the vertebral body. The system includes a working cannula, a reamer, and a guidewire or stylet. The working cannula includes a cannula hub, and a cannula shaft extending from the cannula hub to a distal end of the working cannula. The reamer includes a reamer hub, a reamer shaft extending from the reamer hub, and a reamer head disposed on the reamer shaft. The reamer head includes cutting geometries configured to drill or ream through tissue, and in particular cortical and cancellous bone. The stylet includes a stylet hub, and a stylet shaft extending from the stylet hub and terminating a tip. The stylet hub may include a proximal impaction surface configured to be impacted by a surgical mallet.

The reamer shaft is removably disposed within the working cannula, and the reamer hub is removably coupled to the cannula hub. The reamer hub may include a first reamer coupling feature that is removably coupled with a cannula coupling feature of the cannula hub. Engagement of the coupling features may prevent relative rotation movement in a first rotational direction, yet permit decoupling of the working cannula from the reamer when rotated in a second rotational direction opposite the first rotational direction. With the reamer hub removably coupled to the cannula hub, the reamer head is positioned distal to the distal end of the cannula shaft. The reamer hub defines a reamer hub passageway in communication with a reamer lumen. The reamer hub passageway is configured to removably receive the stylet shaft. With the stylet hub positioned proximal to the reamer hub, the tip of the stylet shaft is positioned distal to the reamer head and distal to the distal end of the reamer.

In certain implementations, the reamer hub includes a second reamer coupling feature configured to be removably coupled with a stylet coupling feature of the stylet hub. The reamer hub includes the first and second reamer coupling features with each being removably couplable to a separate component of the system. The second reamer coupling feature and the stylet coupling feature may be threads.

The reamer hub may include a handle that defines a proximal cavity centrally located with the handle. A handle lug may be disposed with the proximal cavity and be spaced apart from the handle to define an annular gap. The external threads forming the second reamer coupling feature are disposed on the handle lug. The internal threads forming the stylet coupling feature are disposed within the tubular portion.

In certain implementations, the system includes indicia configured to provide the user with an approximate distance by which the tip of the stylet is beyond the distal end of the reamer. The indicia may include markings on the reamer hub. Assessing alignment between a distal edge of the stylet hub and the markings indicates the distance by which the tip of the stylet is beyond the distal end of the reamer.

In certain implementations, the system includes a spacer device removably positionable between the reamer hub and the stylet hub. The spacer device may be removably coupled to the stylet shaft. The spacer device includes a spacer body that defines a slot extending longitudinally from an outer surface of the spacer body to a central bore. A defeatable interference engagement maintains the spacer device on the stylet shaft until it is indicated to decouple it from the stylet shaft. The spacer device may further include flanges disposed on opposing ends of the spacer body, and a grip extending radially from the spacer body.

Therefore, according to certain inventive aspects of the present disclosure, the system includes a working cannula comprising a cannula hub, and a cannula shaft extending from the cannula hub to a distal end. A reamer includes reamer comprising a reamer hub, a reamer shaft extending from the reamer hub and defining a reamer lumen, and a reamer head disposed on the reamer shaft. The reamer shaft is removably disposed within the working cannula with the reamer head positioned distal to the distal end of the cannula shaft with the reamer hub removably coupled to the cannula hub. A stylet includes a stylet hub, and a stylet shaft extending from the stylet hub and terminating a tip. The stylet shaft is removably disposed within the reamer with the tip of the stylet being positioned distal to the reamer head with the stylet hub being positioned proximal to the reamer hub.

According to certain inventive aspects of the present disclosure, the system includes a working cannula comprising a cannula hub, and a cannula shaft extending from the cannula hub to a distal end. A reamer includes a reamer hub, a reamer shaft extending from the reamer hub to a distal end and defining a reamer lumen, and a reamer head disposed on the reamer shaft. The reamer shaft is removably disposed within the working cannula with the reamer head positioned distal to the distal end of the cannula shaft, and wherein the reamer hub comprises indicia. A stylet includes comprising a stylet hub, and a stylet shaft extending from the stylet hub and terminating a tip. The stylet shaft is removably disposed within the reamer, wherein the stylet hub is configured to be aligned with the indicia of the reamer hub to indicate a distance by which the tip of the stylet is positioned distal to the distal end of the reamer.

According to certain inventive aspects of the present disclosure, the system includes a working cannula comprising a cannula hub, and a cannula shaft extending from the cannula hub to a distal end. A reamer includes a reamer hub, a reamer shaft extending from the reamer hub and defining a reamer lumen, and a reamer head disposed on the reamer shaft. The reamer shaft is removably disposed within the working cannula with the reamer head positioned distal to the distal end of the cannula shaft. A stylet includes a stylet hub, and a stylet shaft extending from the stylet hub and terminating a tip. The stylet shaft is removably disposed within the reamer. The reamer hub comprises a first coupling feature configured to be removably coupled with the cannula hub, and a second coupling feature configured to be removably coupled with the stylet hub.

DETAILED DESCRIPTION

The present disclosure is directed to improved systems and methods for providing access to within bony anatomy, such as the vertebral body. The access may facilitate subsequent deployment of an implant, or introduction of other instrumentation or media. The systems disclosed herein may be used with other bony anatomy through which the implant is to be deployed, for example, long bones (femur, humerus), ileum, skull, or the like. Referring to the figures in which like numerals indicate like components, the system20includes a working cannula22, a reamer24, and a guidewire or stylet26. As mentioned, existing systems may implicate the aforementioned components as separate instrumentation to be utilized at specific points in the workflow, however, the system20of the present disclosure structurally and functionally integrates the components into a single unit in a unique and advantageous manner to reduce the number of workflow steps and require less handling of separate instrumentation.

The working cannula22includes a cannula hub28, and a cannula shaft30extending from the cannula hub28to a distal end32of the working cannula22. The distal end32of the cannula shaft30may include geometries configured to engage the cortical bone. The reamer24includes a reamer hub34, a reamer shaft36extending from the reamer hub34, and a reamer head38disposed on the reamer shaft36. The reamer shaft36defines a reamer lumen40. The reamer head38may define a distal end42of the reamer24, as shown, or the reamer head38may be axially spaced apart from the distal end42. The reamer head38includes cutting geometries configured to drill or ream through tissue, and in particular cortical and cancellous bone. A necked portion44may demarcate the reamer head38from a proximal portion of the reamer shaft36. The stylet26includes a stylet hub46, and a stylet shaft48extending from the stylet hub46and terminating a tip50. The tip50may be diamond-shaped or another suitably sharp geometry configured to pierce the pedicle of the vertebral body with an axially-directed force (e.g., impaction). To that end, the stylet hub46may include a proximal impaction surface47configured to be impacted by a surgical mallet to provide the axially-directed force to cause the tip50to pierce and be advanced within the bony anatomy.

The reamer shaft36is removably disposed within the working cannula22, and the reamer hub34is removably coupled to the cannula hub28. The reamer hub34may include a first reamer coupling feature54that is removably coupled with a cannula coupling feature56of the cannula hub28.FIGS.2and3show the first reamer coupling feature54as recesses sized to receive tabs forming the cannula coupling feature56. The engagement between the tabs and the recesses prevents relative axial movement between the working cannula22and the reamer24. The engagement may further prevent relative rotation movement in a first rotational direction, yet permit decoupling of the working cannula22from the reamer24when rotated in a second rotational direction opposite the first rotational direction. In certain implementations, the reamer hub34defines a distal cavity52sized to receive the cannula hub28(seeFIGS.7and8). The first reamer coupling feature54is disposed within the distal cavity52. The first reamer coupling feature54may be tabs sized to be disposed within circular slots forming the cannula coupling feature56. With the reamer hub34removably coupled to the cannula hub28, the reamer head38is positioned distal to the distal end32of the cannula shaft30. In one example, the distal end32of the cannula shaft30is configured to be spaced apart from the reamer head38by a sufficient distance such that, with the reamer head38engaging the pedicle, the distal end32of the working cannula22may be external to soft tissue overlying the pedicle.

The reamer hub34defines a reamer hub passageway58in communication with the reamer lumen40. The reamer hub passageway58is configured to removably receive the stylet shaft48. Therefore, the stylet26is coaxially disposed within the reamer24, which is coaxially disposed within the working cannula22. With the stylet hub46positioned proximal to the reamer hub34, the tip50of the stylet shaft48is positioned distal to the reamer head38and distal to the distal end42of the reamer24. Similarly, the reamer hub34is positioned proximal to the cannula hub28, and the stylet hub46is positioned proximal to the reamer hub34. Existing systems cannot accommodate three-component integration to perform the workflow steps to be described. Rather, as mentioned, existing systems may require a stylet hub to be removed for the stylet to subsequently function as a guidewire.

Referring now toFIGS.1-3showing a first implementation of the system20, the reamer hub34further includes a second reamer coupling feature60configured to be removably coupled with a stylet coupling feature62of the stylet hub46. Therefore, the reamer hub34includes the first and second reamer coupling features54,60with each being removably couplable to a separate component of the system20. The illustrated implementation shows the second reamer coupling feature60and the stylet coupling feature62as complementary threads. Alternatively, the second reamer coupling feature60and the stylet coupling feature62may be selected from the group consisting of a detent, a clip, a spring-loaded pin, interference fit, and friction fit.

With concurrent reference toFIG.5, the reamer hub34may include a handle78that defines a proximal cavity80centrally located with the handle78. A handle lug82may be disposed with the proximal cavity80and be spaced apart from the handle78to define an annular gap, as best shown inFIG.3. The external threads forming the second reamer coupling feature60are disposed on the handle lug82. An inner diameter of a tubular portion of the stylet hub46is sized complementary to the outer diameter of the handle lug82. The internal threads forming the stylet coupling feature62are disposed within the tubular portion, as best shown inFIG.2. With the complementary threads engaged, the axial position of the stylet26is maintained relative to the reamer24; and with the first reamer coupling feature54and the cannula coupling feature56engaged, the axial position of the reamer24is maintained relative to the working cannula22. Therefore, the system20may be selectively manipulated as a single unit for certain steps of the workflow to now be described.

Referring toFIGS.4A-4G, an exemplary workflow is shown in which access to within the vertebral body through the pedicle is achieved with the first implementation of the system20. A percutaneous incision may be made to the soft tissue overlying the pedicle. The tip50of the stylet26is directed through the percutaneous incision. The position of the tip50and the orientation of the system20may be confirmed on fluoroscopy. The system20may be distally advanced into the pedicle (arrow90). For example, the proximal impaction surface47of the stylet26may be impacted with a surgical mallet with the user supporting the system20with the other hand. Alternatively, the user may grasp the reamer hub34and manually provide the necessary forces (e.g., pushing and twisting) to cause the tip50to penetrate through the pedicle and to within the vertebral body. In other words, the user may advance the stylet26while simultaneously operating the reamer24to drill or ream through the pedicle to within the vertebral body. Owing to engagement between the corresponding coupling features54,56,60,62, movement of the stylet hub46relative to the reamer hub34is prevented and the system20may be confidently forced through the pedicle as a single unit. The user may stop advancement upon detecting resistance from the pedicle against the reamer head38, or just after purchase is achieved with the reamer head38within the pedicle.FIG.4Bshows the distal end42of the reamer24engaging the pedicle. With the reamer head38engaging the pedicle, the distal end32of the working cannula22may remain above the overlying soft tissue. Alternatively, the user may stop advancement with the tip50of the stylet26positioned in the posterior one-third of the vertebral body, which may be confirmed on fluoroscopy.

The method includes advancing the stylet and the reamer24to ream through the pedicle.FIG.4Cshows a rotational input (arrow92) being provided to the system20to cause the reamer head38to ream at least partially through the pedicle. The stylet26, whose axial position relative to the reamer24is selectively fixed, is advanced further into the vertebral body. The system20may be advanced through the pedicle by any suitable distance.FIG.4Cshows the distal end42of the reamer24at the cortical wall. In another example, the reamer24may be advanced into the posterior one-third of the vertebral body.

The stylet26is retracted relative to or removed from the reamer24. The stylet coupling feature62may be decoupled from the second reamer coupling feature60. The step may include providing a rotational input (arrow94) to the stylet hub46relative to the reamer hub34to cause the complementary threads to disengage. Particularly in instances where the stylet shaft48is firmly anchored within the cortical or cancellous bone, the threaded interface with the rotational input provides a mechanical advantage to disengage the tip50of the stylet26from the bone. The rotational input may lessen or obviate the need for pulling forces on the system20, which may otherwise shift, dislodge, or loosen purchase between the system20and the tissue. Once disengaged, the stylet26may be axially removed from the reamer24(arrow95), as shown inFIG.4F. The reamer24may be further advanced into the vertebral body, if desired, as shown inFIG.4G. The purchase between the reamer head38and the pedicle may constrain the trajectory of further advancement despite previous removal of the stylet26. Once the reamer head38has formed the working channel to the desired depth, the reamer24may be removed from the working cannula22. The first reamer coupling feature54is decoupled from the cannula coupling feature56, and the reamer24is removed from the working cannula22(arrow98). As best shown inFIG.4H, the result is the working channel formed within the vertebral body for insertion of an implant or subsequent instrumentation through the working cannula22engaging the pedicle. Moreover, since the reamer24was utilized to ream the working channel, the size of the working channel may be ten gauge or larger. The method may include the step of delivering the implant through the working cannula22and to within the vertebral body after the step of removing the reamer24from the working cannula22.

In certain implementations, the system20includes indicia64configured to provide the user with an approximate distance by which the tip50of the stylet26is beyond the distal end42of the reamer24in situ. Referring toFIG.5, the indicia64may include markings66on the reamer hub34. More particularly, a first marking66a, a second marking66b, and a third marking66care spaced apart from one another and positioned adjacent to a slot that permits the handle lug82to be visible. Assessing alignment between a distal edge68of the stylet hub46and the markings66indicates the distance by which the tip50of the stylet26is beyond the distal end42of the reamer24. For example, the markings66may be spaced apart from one another at fixed intervals, such as one centimeter. Should the distal edge68be aligned with the first marking66a, it may be assumed the stylet shaft48is extending beyond the distal end42of the reamer24by three centimeters. And should the distal edge68be aligned with the second marking66bor the third marking66c, it may be assumed the stylet shaft48is extending beyond the distal end42of the reamer24by two centimeters and one centimeter, respectively. Therefore, the user may incrementally advance the reamer24within the vertebral body while alternatingly withdrawing the stylet26. Among other advantages, the arrangement ensures the tip50of the stylet26does not become unduly close to the anterior cortical wall. Further, once sufficient purchase is established between the reamer head38and the pedicle, the guidance provided of the stylet shaft48is of increasingly less necessity and may be retracted or removed.

Returning to the workflow,FIG.4Dshows the step of rotating the stylet hub46(arrow94) to retract the stylet26relative to the reamer24(and the working cannula22). The distal edge68of the stylet hub46is aligned with the second marking66b, and it observable that the distance by which the tip50is beyond the distal end42of the reamer24is less than that ofFIGS.4A-4C. Likewise,FIG.4Eshows the distal edge68of the stylet hub46being aligned with the third marking66c, and it observable that the distance by which the tip50is beyond the distal end42of the reamer24is less than that ofFIG.4D.

A second implementation of the system20is shown inFIGS.6-8with like numerals indicating like components. Again, the working cannula22includes the cannula hub28, and the cannula shaft30extending from the cannula hub28. The reamer24includes the reamer hub34, the reamer shaft36extending from the reamer hub34, and the reamer head38disposed on the reamer shaft36. The stylet26includes the stylet hub46, and the stylet shaft48extending from the stylet hub46and terminating the tip50. It is appreciated that the form factor of the hubs28,34,46vary from the first implementation, and the certain ergonomic differences to the form factor may be interchangeable between the implementations. It is further observed that the tip50of the stylet26is approximately in registration with the distal end42of the reamer24, which also varies from the first implementation.

The system20includes a spacer device70removably positionable between the reamer hub34and the stylet hub46. More particularly, the spacer device70is configured to be removably coupled to the stylet shaft48. In one example, the spacer device70is configured to be clipped onto the stylet shaft48. The spacer device70includes a spacer body74that defines a slot76extending longitudinally from an outer surface of the spacer body74to a central bore. The slot76is sized to receive the stylet shaft48. A defeatable interference engagement maintains the spacer device70on the stylet shaft48until it is indicated to decouple it from the stylet shaft48. The spacer device70may further include flanges72disposed on opposing ends of the spacer body74, and a grip77(seeFIG.9B) extending radially from the spacer body74.

When positioned between the reamer hub34and the stylet hub46, the spacer device70configured to prevent distal movement of the stylet26relative to the reamer24. More particularly, the flanges72are configured to be positioned in an abutting relationship the reamer hub34and the stylet hub46such that the axially-directed force on the proximal impaction surface47of the stylet hub46is effectively transferred to the reamer hub34. Further, a length of the spacer device70defined between the flanges72is such that, with the spacer device70disposed between the stylet hub46and the reamer hub34, the tip50of the stylet shaft48is in registration with the distal end42of the reamer shaft36.

Referring now toFIGS.9A-9G, an exemplary workflow is shown in which access to within the vertebral body through the pedicle is achieved with the second implementation of the system20. The tip50of the stylet26is directed through the percutaneous incision to engage the pedicle. The position of the tip50and the orientation of the system20may be confirmed on fluoroscopy. During initial insertion of the system20, the spacer device70prevents distal movement of the stylet hub46towards the reamer hub34. It is observed that the distal end32of the working cannula22may remain above the overlying tissue, whereas the reamer head38may be closer the pedicle at this point more so than the first implementation of the system20.

The spacer device70is removed from between the reamer hub34and the stylet hub46. For example, the user may pinch the grip77and decouple the spacer device70from the stylet shaft48. The stylet26is then advanced within the reamer24such that the tip50of the stylet26is deployed through the pedicle and to within the vertebral body (arrow90). The step of advancing the stylet26may include impacting the proximal impaction surface47of the stylet26with the surgical mallet. The stylet hub46may be moved into an abutting relationship with the reamer hub34, or a portion of the distance thereto. Owing to the tip50of the stylet26being in registration with the distal end42of the reamer24, the distance by which the stylet hub46is moved towards the reamer hub34may be assumed to be the distance by which the tip50of the stylet26is positioned beyond the reamer24. This distance may be tuned (based on the length of the spacer device70) such that the tip50of the stylet26is positioned in the posterior one-third of the vertebral body. The user may also advance the reamer24to achieve purchase with the reamer head38. For example,FIG.9Cshows the distal end42of the reamer24engaging the pedicle.

FIG.9Dillustrates the step of advancing the reamer24along the stylet26. The reamer24may be operated to drill or ream through the pedicle with the reamer head38. The rotational input (arrow92) being provided to the reamer hub34causes the reamer head38to ream at least partially through the pedicle. Unlike the first implementation, the relative axial position between the stylet26and the reamer24is not constrained, and therefore resistance on the tip50from the cancellous bone may cause the axial position of the stylet26to be maintained as the reamer24is advanced. In other words,FIG.9Dshows the distal end42of the reamer24adjacent the cortical wall with the stylet hub46now again spaced apart from the reamer hub34. In another example, the reamer24may be advanced into the posterior one-third of the vertebral body.

The stylet26is removed from the reamer24(arrow95). The reamer24may be further advanced into the vertebral body, if desired, as shown inFIG.9F. Again, the purchase between the reamer head38and the pedicle may sufficiently constrain the trajectory with further advancement of the reamer24. Once the reamer head38has formed the working channel to the desired depth, as confirmed on fluoroscopy, the method may include advancing the working cannula22along the reamer24such that the working cannula22engages the pedicle.FIG.9Gshows the working cannula22being directed distally (arrow99) for the distal end32of the working cannula22to have purchase within the pedicle. Prior to advancing the working cannula22, the cannula hub28may be decoupled from the reamer hub34. More particularly, the first reamer coupling feature54may be decoupled from the cannula coupling feature56through rotation or another input. Once decoupled, the working cannula22may be slid along the reamer shaft36. Thereafter, the reamer24may be removed from the working cannula22(arrow98). As best shown inFIG.9H, the working channel is formed within the vertebral body for insertion of an implant or subsequent instrumentation through the working cannula22engaging the pedicle.

Certain inventive aspects of the present disclosure are described with reference to the following exemplary clauses:Clause 1—A system for providing access to within a vertebral body through a pedicle, the system comprising: a working cannula comprising a cannula hub, and a cannula shaft extending from the cannula hub to a distal end; a reamer comprising a reamer hub defining a reamer hub passageway, a reamer coupling feature within the reamer hub passageway, a reamer shaft extending from the reamer hub and defining a reamer lumen coaxial with the reamer hub passageway, and a reamer head disposed on the reamer shaft, wherein the reamer shaft is removably disposed within the working cannula with the reamer head positioned distal to the distal end of the cannula shaft; and a stylet comprising a stylet hub, a stylet coupling feature disposed on the stylet hub, and a stylet shaft extending from the stylet hub and terminating a tip, wherein the stylet coupling feature is configured to be removably coupled with the reamer coupling feature.Clause 2—The system of clause 1, wherein the reamer coupling feature and the stylet coupling feature are selected from the group consisting of complementary threads, a detent, a clip, a spring-loaded pin, interference fit, and friction fit.Clause 3—A system for providing access to within a vertebral body through a pedicle, the system comprising: a working cannula comprising a cannula hub, and a cannula shaft extending from the cannula hub to a distal end; a reamer comprising a reamer hub, a reamer shaft extending from the reamer hub and defining a reamer lumen, and a reamer head disposed on the reamer shaft, wherein the reamer shaft is removably disposed within the working cannula with the reamer head positioned distal to the distal end of the cannula shaft; and a stylet comprising a stylet hub, and a stylet shaft extending from the stylet hub and terminating a tip, wherein the stylet shaft is removably disposed within the reamer, a spacer device removably positionable between the reamer hub and the stylet hub.Clause 4—The system of clause 3, wherein the spacer device is configured to be removably coupled to the stylet shaft.Clause 5—The system of clause 3 or 4, wherein the spacer device includes a spacer body defining a central bore, and a slot extending longitudinally from an outer surface of the spacer body to the central bore, wherein the slot is sized to receive the stylet shaft.Clause 6—The system of clause 5, wherein the spacer device further includes flanges disposed on opposing ends of the spacer body.Clause 7—The system of clause 5 or 6, wherein the spacer device further includes a grip extending radially from the spacer body.Clause 8—A method of providing access to within a vertebral body through a pedicle with a system including a working cannula, a reamer removably disposed within the working cannula and including a reamer hub and a reamer head, a stylet removably disposed within the reamer and including a stylet hub and a stylet shaft, and a spacer device removably disposed between the reamer hub and the stylet hub, the method comprising the steps of: inserting a tip of the stylet into the pedicle of the vertebral body, wherein the spacer device prevents distal movement of the stylet hub relative to the reamer hub; removing the spacer device from between the reamer hub and the stylet hub; advancing the stylet within the reamer and such that the tip of the stylet is deployed through the pedicle and to within the vertebral body; thereafter, advancing the reamer along the stylet while operating the reamer to drill through the pedicle with the reamer head; removing the stylet from the reamer; advancing the working cannula along the reamer such that a distal end of the working cannula engages the pedicle; and removing the reamer from the working cannula.Clause 9—The method of clause 8, wherein the spacer device is removably coupled to the stylet shaft, wherein the step of removing the spacer device further includes decoupling the spacer device from the stylet shaft.Clause 10—The method of clause 8 or 9, wherein the step of advancing the stylet within the reamer further includes impacting the stylet hub with a surgical mallet.Clause 11—The method of any one of clauses 8-10, wherein the step of deploying the tip of the stylet deployed through the pedicle and to within a posterior one-third zone within the vertebral body.Clause 12—A method of providing access to within a vertebral body through a pedicle with a system including a working cannula, a reamer removably disposed within the working cannula and including a reamer hub and a reamer head, a stylet removably disposed within the reamer and including a stylet hub, and coupling features removably coupling the reamer hub and the stylet hub, the method comprising the steps of: inserting a tip of the stylet into the pedicle of the vertebral body, wherein the coupling features prevent movement of the stylet hub relative to the reamer hub; advancing the stylet and the reamer to engage the reamer head with the pedicle; decoupling the coupling features; removing the stylet from the reamer; operating the reamer to drill through the pedicle with the reamer head; advancing the working cannula along the reamer such that a distal end of the working cannula engages the pedicle; and removing the reamer from the working cannula.Clause 13—The method of clause 12, further comprising stopping advancement the stylet and the reamer upon detecting resistance from the pedicle.Clause 14—The method of clause 12 or 13, wherein the coupling features are complementary threads, the method further comprising rotating the stylet hub relative to the reamer hub to decouple the complementary threads, thereby providing a mechanical advantage to disengage the tip of the stylet engaged with the pedicle.Clause 15—The method of any one of clauses 12-14, further comprising, prior to the step of decoupling the coupling features: retracting the stylet relative to the reamer; and visualizing alignment between the stylet hub and indicia on the reamer hub, wherein the alignment is indicative of a distance by which the tip of the stylet is beyond a distal end of the reamer.Clause 16—The method of any one of clauses 12-15, further comprising, prior to the step of decoupling the coupling features, alternatingly retracting the stylet relative to the reamer and advancing the reamer within the pedicle.Clause 17—The method of any one of clauses 12-16, further comprising advancing the stylet while simultaneously operating the reamer to drill through the pedicle to within the vertebral body.Clause 18—The method of any one of clauses 8-17, wherein a cannula hub of the working cannula is removably coupled to the reamer hub, the method further comprising decoupling the cannula hub from the reamer hub prior to the step of advancing the working cannula along the reamer.Clause 19—The method of any one of clauses 8-18, further comprising delivering an implant through the working cannula and to within the vertebral body after the step of removing the reamer from the working cannula.