Patent ID: 12232757

DETAILED DESCRIPTION

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

Additionally, to the extent that linear or circular dimensions are used in the description of the disclosed devices and methods, such dimensions are not intended to limit the types of shapes that can be used in conjunction with such devices and methods. A person skilled in the art will recognize that an equivalent to such linear and circular dimensions can easily be determined for any geometric shape. Further, in the present disclosure, like-numbered components of the embodiments generally have similar features. Still further, sizes and shapes of the devices, and the components thereof, can depend at least on the anatomy of the subject in which the devices will be used, the size and shape of components with which the devices will be used, and the methods and procedures in which the devices will be used.

Example Powered Cutting Systems

FIG.1is an illustration of one embodiment of a bone and tissue resection device according to aspects of the embodiments disclosed herein.FIG.1shows a bone and tissue resection device10that includes a stationary assembly200and a drive assembly100slidably coupled with the stationary assembly200. The drive assembly100includes a housing101that is coupled with a motor20(e.g., a source of continuous rotational motion) and a thumb trigger190positioned to allow a user to slide the drive assembly in the distal (D) direction with respect to the stationary assembly200. The stationary assembly200includes a frame201that is slidably engaged with the housing101of the drive assembly and a handle290sized and shaped to allow a user's fingers and/or palm hold onto the handle290of the stationary assembly200while the user's thumb actuates the thumb trigger190of the drive assembly190. The stationary assembly200includes a spring270positioned in the frame201. The spring270is positioned to bias the drive assembly100in a proximal (P) direction against the force of the user against the thumb trigger190, thus maintaining the normally open position of the cutting region250. In some embodiments, the spring270is positioned to bias the oscillator100distally inside the stationary assembly200such that the cutting region250is normally closed. Actuating the oscillator100in this configuration forces the cutting region250open and releasing the trigger190would cause the spring270to provide a constant force on the blade until it closes and makes the cut in the cutting region250.

The stationary assembly200includes a shield assembly220that extends from the frame201to a footplate222at the distal end. In some embodiments, the shield assembly220is integrated with the stationary assembly.FIG.1shows a shield assembly220that is coupled to a distal end of the frame201of the stationary assembly200with a clip228. The shield assembly220includes an elongated sleeve221that extends distally from the frame201to a cutting region250where there is a window opening along the shield assembly220from a distal end of the elongated sleeve221to the footplate at the distal end of the shield assembly220. The shield assembly220is configured to protect a blade (not visible) that is coupled to the drive assembly100.

In operation, the drive assembly100transfers energy to the blade from the motor (e.g., causes the blade to oscillate or rotate inside the shield assembly220) and actuation of the thumb trigger190(e.g., a force applied in the distal direction by a user holding the handle290) slides the drive assembly100distally against the bias force of the spring270. The distal movement of the drive assembly causes the blade to pass through the cutting region250. Tissue or bone present in the cutting region250is contacted and resected by the blade as it passes though. In some embodiments, the blade is a crescentic blade that oscillates at a high frequency with a small angular deviation. In some embodiments, the blade is abrasive and will be less effective at cutting soft tissue than it will bone thus improving safety.

FIG.2is an illustration of the stationary and drive assemblies of the bone and tissue resection device ofFIG.1.FIG.2show the stationary assembly200and drive assembly100with the handle290of the stationary assembly detached from the frame201of the stationary assembly. In some embodiments, the handle290is integrated with the frame201.FIG.2shows the frame201includes an interface209for securing a separate handle290to the stationary assembly200. The shield assembly220is attached to the frame201of the stationary assembly220with a clip228that engages with a distal channel227formed in the frame201. The cutting region250of the shield assembly220includes two support members223that connect the foot plate222to the distal end of the elongated sleeve221. Also visible is a blade tip of a blade300disposed inside the shield assembly220and attached to the drive assembly via a blade shaft (not visible). The drive assembly100includes a button actuator181extending through the housing101for releasing the blade shaft from being coupled with the drive mechanism inside the housing101. The proximal end of the drive assembly100includes a coupling mechanism182for attaching the motor20to the drive mechanism. When coupled, continuous rotational motion from the motor20is delivered to a drive mechanism inside the housing101of the drive assembly100. Additionally,FIG.2shows the frame201of the stationary assembly includes a latch261that can prevent the drive assembly100from decoupling with the frame201when in the first illustrated position (e.g., via a protrusion262that interferes with proximal motion of the drive assembly100relative to the frame201) and can be moved to a second position (e.g., by rotating a proximal end of the latch261in the direction of arrow263) to allow decoupling of the drive assembly100from the frame201(e.g., by withdrawing the drive assembly100proximally with respect to the frame201).

FIG.3Dis an illustration of how in operation, a disposable blade300can be attached to the drive assembly100while the drive assembly is separated from the stationary assembly200and a disposable shield assembly220is attached to the stationary assembly. Afterwards, the distal end of the blade300can be inserted into the shield assembly220and slid distally until the drive assembly100is engaged with the stationary assembly200and retained by the latch261. In this position, the drive assembly can be biased proximally against the latch261by the spring270, which positions the distal tip of the blade300at the proximal end of the cutting region250. When a user presses on the thumb trigger190in the distal direction, the drive assembly moves against the bias force of the spring270to drive the blade300through the cutting region to conduct a cutting operation.

FIG.3Ais an illustration of another embodiment of a bone and tissue resection device10according to aspects of the embodiments disclosed herein.FIG.3Ashows a bone and tissue resection device10with a different handle390attached to the frame201of the stationary assembly200.FIG.3Ashows the motor20is coupled to an external controller or power source via a line22connected to the motor20with an articulating coupling21.FIG.3Aalso shows that the blade300is a crescentic blade that is configured to be oscillated by an oscillator mechanism of the drive assembly100. The crescentic blade can span the width of the two support beams223of the shield assembly220such that the cutting region250(e.g., the path of the blade300) is an arc from one support beam223to the other support beam223across the width of the shield assembly220that extends from a distal end of the elongated sleeve221(e.g., where the distal end of the blade300is first exposed as it is move distally by the drive assembly) to the foot plate222. In some embodiments, the cutting region250does not extend all the way to the foot plate222to prevent the blade300contacting the footplate222. The blade300extends inside the support beams223but, in some embodiments, and as shown, has a crescentic or generally arcuate shape that forms the cutting region above the support beams223, but not below, such that there is a window224extending between the support beams223opposite the blade300. The window224can allow a user or imaging device to observe the cutting region250and blade300as it contacts and resects tissue. The open window configuration thus enables the blade300to be viewed from both sides (e.g., directly from above in the orientation of the figure and through the window224from below in the orientation of the figure) as it passes through the cutting region250. This can be advantageous because, in use, a resection device such as a burr or Kerrison Rongeur is often positioned against bone or tissue in a manner that obstructs direct visualization of the blade300from above in the orientation of the figure. Therefore, in prior devices without any window224, a surgeon or other user can be forced to perform final positioning for a resection cut without being able to see the blade directly.

In some embodiments, the an oscillator mechanism of the drive assembly100includes a mechanical arrangement configured to convert continuous rotational motion from a motor, which may be, for example, an internal motor or an external motor20attached to the drive assembly, into an oscillating movement for oscillating the blade300. In some embodiments, the oscillator comprises a piezoelectric mechanism for oscillating the blade300at ultrasonic frequencies. In some embodiments, the oscillator oscillates the blade300around the proximal-distal axis of the blade300. In other embodiments, the oscillator oscillates the blade300axially along proximal-distal axis of the blade300. In other embodiments, the oscillator oscillates the blade300axially along proximal-distal axis of the blade300and around the proximal-distal axis of the blade300.

FIG.3Bis an illustration of the stationary assembly200of the bone and tissue resection device10ofFIG.3A.FIG.3Bshows the frame201of the stationary assembly200with the drive assembly100removed or not yet inserted. The handle390is shown attached to the interface209of the frame201via a plurality of screws399. The handle390includes a first gripping portion391and a second gripping portion392, both on the distal face of the handle390. The second gripping portion392is sized and shaped to be engaged by the index finger of a user's hand that is grasping the handle390, and the first gripping portion391is sized and shaped to be engaged by one or more of the user's remaining fingers.

The frame201is shown to have a generally C-shaped cross-section that defines a channel260that accepts the exterior of the housing101drive assembly100. The channel260includes rail features262along the channel260. The rail features262permit the housing101to slide along a single axis of translation (e.g., along the proximal and distal directions). In some embodiments, the frame201can completely encapsulate the drive assembly100instead of just being a C-shaped cross-section. In these circumstances, the guide protrusions on the drive assembly106and mating rail feature on the frame262are no longer necessary but can still be used to constrain movement. The distal end of the frame201includes an opening221′ that is sized to accept the blade300when the drive assembly100is inserted into the stationary assembly200. The distal end of the frame201also provides a surface to be engaged by the spring270for biasing the drive assembly100in the proximal direction. The distal end of the frame201also includes channels227for securing the clip228of the disposable shield assembly220to the stationary assembly200. The proximal end of the frame201includes a latch261for retaining the drive assembly in the channel260of the frame201. In operation, the drive assembly100is slid into the channel260and engaged with the rail features262, and then the drive assembly slides distally along the path defined by the rail features262until secured by the latch261, which prevents the drive assembly100from being removed (e.g., moved in the proximal direction to disengage from the rail features262). To decouple the components, a user can toggle the latch262(e.g., as described above) to release the drive assembly100and retract the drive assembly100proximally to decouple the drive assembly100from the stationary assembly200.

FIC.3C is an illustration of the drive assembly100of the bone and tissue resection device10ofFIG.3A.FIG.3Cshows the drive assembly100separate from the stationary assembly200. In some embodiments, the drive assembly100is configured to be used as a free-hand resection device without being coupled with a stationary assembly200. InFIG.3C, a blade shaft shield120is shown extending distally from the housing101. The blade shaft shield120is configured to protect and constrain the blade shaft between the exit of the housing101and the blade300positioned at the distal end of the blade shaft (as shown inFIG.3D). In operation, a proximal end of the blade shaft can be inserted at an opening122in the distal tip121of the blade shaft shield120and the blade shaft can be slid proximally until it engages with a drive mechanism inside the housing101. In some embodiments, the user can first press the button actuator181to enable the blade shaft to be engaged with the drive mechanism. In other embodiments, the button actuator181may only need to be depressed to release the blade from the drive mechanism and an applied insertion force to the blade shaft can engage the coupling mechanism without actuation of the button actuator181(e.g., via a one-way latch, such as those commonly used on doors, etc.).

FIG.3Cshows the housing101of the drive assembly having guide protrusions106extending from the housing. The guide protrusions106are configured to engage with the rail features262of the frame201of the stationary assembly200, as shown inFIG.3B. The distal end of the housing101includes a protrusion102that engages the spring270of the stationary assembly100.FIG.3Dis an illustration of the distal end of the drive assembly101ofFIG.3Cwith a blade300attached.FIG.3Dshows the crescentic blade300with a blade shaft310extending proximally from the blade300into the blade shaft shield120. In the illustrated position, the blade300is fully inserted into the blade shaft shield120and a proximal end of the blade shaft310is coupled with the drive mechanism inside the housing101. The blade300is free to oscillate or rotate about the major axis of the blade shaft310, depending on the type of drive mechanism that is in the housing101. In some embodiments, the blade can be a circular blade or a coring blade. In operation, a user can free-hand use the drive assembly in this configuration. It should also be noted that a user could change between using the drive assembly free-hand and in connection with a stationary, as well as perhaps using different blade types in each configuration, multiple times during a procedure.

Further, while the above-described embodiments illustrate configurations in which movement of the drive assembly100with respect to the stationary assembly200is manually actuated, in other embodiments a bone and tissue resection device10can include a powered actuator for moving the drive assembly100with respect to the stationary assembly200. In such embodiments, a user of the bone and tissue resection device10can electrically or mechanically control the powered actuator to move the drive assembly100and thereby move the blade300in the cutting region250.

Example Crescentic Blade Cutting Assemblies

FIGS.4A-4Care illustrations of an embodiment of a distal end of a device according to aspects of the embodiments disclose herein, such as the device10described above.FIG.4Ashows a first embodiment of a cutting assembly400that includes the disposable shield220and the blade300. The cutting assembly400defines a cutting region250between a closed footplate420at the distal end and an opening229of the distal end of the elongated sleeve221of the shield assembly220. The closed footplate420can be coupled to the shield assembly220by a single support beam430that spans a length of the cutting region250. In some embodiments, the support beam430can be split into multiple support beams to allow for visualization of the cutting area. The support beam430can be sized and shaped to be inside of the path of the blade300as it transits the cutting region250. In some embodiments, and as shown, the blade300can be a crescentic blade that surrounds the support beam230. In some embodiments, a cutting tip301of the blade300cuts toward the closed footplate420but stops short of contacting the footplate due to a feature on the blade that abuts a corresponding feature on the shield220in order to prevent teeth of the cutting tip301from contacting the footplate420directly. In other embodiments, contact between the blade and footplate can be controlled in other ways, including by designing the length of longitudinal translation of the blade to make contact impossible, etc. In some embodiments, the blade300comprises a cutting tip301with any of a variety of toothed designs or a diamond grit blade, etc. In some embodiments, and as shown in more detail inFIG.6B, the shield assembly220can include a feature attached to the support beam430that rests on or against an inside diameter of the crescentic blade to wipe off the inner diameter of the blade upon retraction of the blade proximally relative to the feature after a cut is made.

In operation, a drive assembly100, to which the blade300is attached, can be moved distally with respect to a stationary assembly200, to which the shield assembly220is attached, and this relative motion between the blade300and the shield assembly220can move the blade300though the cutting region250. With the blade300being rotated or, as illustrated, oscillated, by a drive mechanism in the drive assembly100, any tissue or bone present in the cutting region250can be contacted by the cutting tip301of the blade300and resected. In some embodiments, bone or tissue disposed in the cutting region250can be prevented from moving out of the path of the blade300contacting a proximal surface of the footplate422.

The proximal surface of the footplate422can include a crescentic trough region421that forms an outer lip422and an inner lip423. The outer lip422can extend to an outer peripheral edge424of the footplate such that the outer lip422can define a sharpness that is a function of the width of outer lip422at the peripheral edge424and the angle of the trough421as it approaches the peripheral edge424. In operation, the cutting tip301of the blade300can approach the trough of the foot plate421and the outer lip422can engage with an outer edge of the cutting tip301in an overlapping jaw-like fashion, such that the fully extended position of the blade300locates the cutting tip301distally equal to or beyond the position of the outer lip422(while still allowing some separation between the blade tip301and the surface of the trough region421). In some embodiments, the cutting tip301does not extend distally to the outer lip422, but close enough to effectively cut tissue or bone therebetween. Similarly, the inner lip423engages with an inner edge of the cutting tip301, such that the fully extended position of the blade300locates the cutting tip301distally equal to or beyond the position of the inner lip423. In some embodiments, and as shown, the support beam430has a generally flat inner-facing surface and an outer edge431that has a width less than a corresponding inner cord section of the blade300to allow the blade to pass distally across the support beam430. In some embodiments, this inner facing surface432is cupped or has an opening to increase the amount of material that is in the opening for resection.

FIG.4Bshows the full length of the elongated sleeve221, from the opening229at the distal end to a proximal end configured to attach to the stationary assembly200. Inside the elongated sleeve221is the blade shaft310, showing the proximal edge extending beyond the elongated sleeve221to be coupled with the drive assembly100to actuate (e.g., oscillate) the blade300. In operation, when the drive assembly100is moved distally, the blade shaft310is moved distally into the elongated sleeve221of the shield assembly220.FIG.4Cshows the arrangement of the blade300around the support beam430. In some embodiments, the proximal end439of the support beam430can be configured to abut a distal face of a proximal end of the blade (e.g., the opposite side of face390ofFIG.3A) when the blade reaches a designed maximum distal extension through the cutting region250. This arrangement can prevent the cutting tip301of the blade300from contacting the footplate420by having the distal face of the blade contact the proximal end439of the support beam430before the cutting tip301contacts the footplate420and prevent further distal translation of the blade300.

FIG.5is an illustration of another cutting assembly500according to aspects of the embodiments disclose herein.FIG.5shows the cutting assembly500includes the shield assembly220with an elongated tube221surrounding a blade300and a footplate520at a distal end of the shield assembly220. The footplate520is connected to the distal end of the elongated tube221by two support beams530. In some embodiments, the cutting assembly500includes only one support beam530, however the use of two support beams can increase rigidity of the assembly and better resist deflection during use, etc. In some embodiments, a plate covers the opening created by the support beam(s)530to encapsulate the cutting region250allowing for tissue extraction after resection. The blade300can be nested inside the support beams530and configured to extend though the cutting region (indicated by arrow250) during a cutting operation. The footplate520can include an outer lip521that extends to the peripheral edge522of the footplate to engage with the cutting tip301of the blade300as discussed above with respect toFIG.4A. The footplate520can be totally closed or partially open. For example, an open footplate is shown inFIGS.17A and17B(e.g., open distal end1722). The outer diameter of the support beams530are the same diameter as the elongated tube221in this embodiment.

InFIG.5, the support beams530include an inner surface having a ridge536that marks a location where the support beam530transitions from a first sidewall thickness535to a second sidewall thickness537that is greater than the first thickness. More particularly, the support beam530can extend radially inward to achieve the second thickness537at points below the maximum angular reach of the oscillating blade300in order to add strength and stiffness to the support beams530. Above the ridge536, the support beam530can maintain the first sidewall thickness536that is configured to conform to or accommodate the outer diameter of the blade300as it passes through the cutting region530. The support beams530rigidly locate the footplate520to enable the blade300to deliver a force to the tissue or bone in the cutting region250by pressing the tissue or bone against the footplate as the blade advances toward the footplate. Preventing deflection of the footplate520can enable the blade300to deliver a larger force to the tissue or bone and more successfully resect tissue.

FIGS.6A and6Bare illustrations of another embodiment of a cutting assembly600for use with a drive assembly100and stationary assembly200according to aspects of the embodiments disclosed herein.FIG.6Ashows a cutting assembly600that includes a shield assembly220and a footplate620connected to the distal end of the elongated sleeve221of the shield assembly220by two support beams630. The support beams can include opposing inner faces636that are configured to allow the blade300to pass inside and along the inner faces636as the blade300moves through the cutting region250. The support beams630can have a thickness635to provide the support beams620sufficient stiffness and strength to rigidly locate the footplate620with respect to the blade300during a cutting operation where the blade drives bone, for example, against the footplate620as the cutting tip301is advanced into the bone. The footplate620also includes a lip621that extends to a peripheral edge622of the footplate620, similar to the embodiments described above. In some embodiments, the footplate can include an inner curved surface that curves proximally from a proximal face623of the footplate to the lip621. The curved inner surface can be configured to allow the cutting tip301to move distally past the lip621without contacting proximal face623to improve the cutting action of the cutting tip301. The outer diameter of the support beams630can be larger than the elongated tube221, as shown in this embodiment.

FIG.6Bshows the cutting assembly600with the blade300removed to show that the cutting assembly includes a cleaning plate225in the opening229at the distal end of the elongated sleeve221. The cleaning plate225and sidewall of the sleeve221define a crescentic opening226that the blade300passes through to enter the cutting region250. The cleaning plate225therefor runs along the inner surface of the blade300and, as the blade is retracted proximally into the elongated sleeve221, for example by the biasing force of the spring270moving the drive assembly proximally, the cleaning plate225can remove any resected tissue or debris attached to the blade300after a cutting stroke through the cutting region250. In some embodiments, the improved cutting action of the oscillating blade300can cleanly resect a mass of tissue without pulverizing, fragmenting, or otherwise breaking it into several smaller pieces. In such embodiments, the cleaning plate225can serve to retain the resected mass of tissue between the cleaning plate and the footplate620as the blade300is retracted proximally. A grasping surgical instrument can then be used to remove the resected mass (e.g., through the window624) and clear the cutting region250for another use. In other embodiments, the resected mass can be cleared using a suction instrument rather than a grasper, while in still other embodiments the instrument can simply be positioned for another use and movement of new tissue into the cutting region624can eject the resected tissue mass through the window624. The outer diameter of the support beams630can be larger than the elongated tube221, as shown in this embodiment.

In some embodiments, any of the various cutting assemblies or distal end assemblies described above can include one or more sensors to aid in positioning the instrument at a surgical site. For example, one or more sensors can be positioned along the footplate, blade, shield sleeve, or support arms to detect proximity to one or more anatomical structures, such as nerves, blood vessels, etc. Any of a variety of known sensors can be employed, including optical sensors, electromagnetic sensors (e.g., electrodes), pressure sensors, etc. Such sensors can be disposed along an exterior surface of the device or integrated into the device. In addition, embodiments formed from materials not readily visible in a particular type of medical imaging, e.g., fluoroscopy, etc. can include one or more markers attached thereto or embedded throughout made from a material visible with such imaging.

Example Drive Assembly Actuation

The following figures illustrate different configurations for the actuation of the drive assembly100with respect to the stationary assembly200.

FIGS.7A-7Care illustrations of one embodiment of a bone and tissue resection device700having a pivoting trigger730configured to actuate the movement of the drive assembly100.FIG.7Aillustrates a bone and tissue resection device700having a stationary assembly702with a pistol grip handle729connected to a frame720and a pivoting trigger730configured pivot about an axis733and push the drive assembly100distally.

In operation, the pivoting trigger730can be moved (indicated by arrow799) from an extended position731buntil a lever arm732of the pivoting trigger730contacts the drive assembly100(e.g., at a proximal lip734, seeFIG.7C) directly or indirectly so that pulling the pivoting trigger730further advances the drive assembly100and the blade shaft shield120distally against the biasing force of a spring270. The movement799can drive the blade (not shown, e.g., blade300described above) into the cutting region250in the shield assembly220. The pivoting trigger730can be moved to a fully retracted position731awhere the drive assembly100is advanced distally as far as possible. In some embodiments, a stop mechanism in the shield assembly220can contact the blade300to prevent further distal movement of the drive assembly. A sliding or stationary stop block728can also prevent the trigger from overextending in the “locked” position (as shown). Sliding the stop block728to the “unlocked” position (indicated by arrow797) can push the pivoting trigger730out of contact with the drive assembly100, allowing the drive assembly100to be removed or inserted into the housing720of the stationary assembly702. After inserting the drive assembly100into the stationary assembly720, pulling the pivoting trigger730can push the stop block728back into the “locked” position. A spring729can be mounted in the frame720and can push on the drive assembly, taking up tolerances and reducing rattle between moving parts, for example, the drive assembly101and the frame720.FIG.7Bis a perspective view of the bone and tissue resection device700.FIG.7Cis a detail view of the bone and tissue resection device700, where the stationary assembly702is translucent, showing the engagement of the pivoting trigger730with the drive assembly100.

FIG.8is an illustration of another embodiment of a bone and tissue resection device800having an alternative grip and trigger arrangement. In particular, the embodiment ofFIG.8includes a proximal handle829attached to the drive assembly100and a trigger830attached to a frame820of a stationary assembly802. In operation, the handle829and trigger830can be squeezed together by a user's hand, thereby advancing the drive assembly100distally (e.g., against biasing force from spring270not visible inFIG.8) to advance the blade300within the cutting region250toward the footplate222.FIG.8shows the handle829and trigger830in their fully compressed position, wherein the blade300is advanced distally through the cutting region250. Releasing the compression between handle829and trigger830from this position can allow a biasing force (e.g., from spring270not visible inFIG.8) to withdraw the drive assembly100proximally with respect to the frame820and trigger830, thereby withdrawing the blade300proximally through the cutting region and into the shield assembly220.

FIG.9A-9Dare illustrations of one embodiment of a bone and tissue resection device900having a rack and pinion that control movement between a stationary assembly902and a drive assembly100.FIG.9Ashows a stationary assembly902that includes a frame920having a handle929and a trigger930that is slidably coupled to the frame920. The trigger930can translate or slide proximally and distally with regard to the handle929. An opposing rack-and-pinion mechanism960is configured to move the drive assembly100distally when pulling the trigger930proximally toward the handle929by interaction of one rack963on the trigger930, one rack160on the drive assembly100, and a pinion or gear961positioned between them and rotatably mounted to the frame920, as shown in more detail inFIG.9B. In some embodiments, two pinions961,961′ can be utilized and can be spring-loaded or otherwise biased toward one other to engage two angled racks, as shown in more detail inFIGS.9C and9D. Biasing the pinions961,961′ in this manner can help maximizes engagement with the racks and takes up tolerances, thereby reducing rattle between the various moving parts in the device900.

FIG.9Bshows the rack and pinion mechanism960between the trigger930and the drive assembly100in greater detail. The stationary assembly902can include a spring927biasing the trigger930away from the handle929. The rack and pinion mechanism960can include a bottom rack963on the trigger positioned below the housing101of the drive assembly, a top rack160on the housing101of the drive assembly100positioned above the bottom rack963, and a pinion961positioned between the top rack160and the bottom rack963. In operation, the trigger930can be driven proximally (as indicated by arrow998) by the fingers of a user's hand squeezing together the handle929and trigger930. As the trigger930translates proximally relative to the handle929, the rack963also translates proximally. The pinion961, which is coupled to the frame920, rotates and causes the rack160to translate the drive assembly100distally (indicated by arrow999).FIG.9Balso shows the drive assembly100secured in place by a latch mechanism928, which is shown is more detail inFIGS.10E and10D.

FIG.9Cis a cross-sectional view of the bone and tissue resection device900taken along the line A-A inFIG.9B, showing one exemplary geometry of a rack and pinion mechanism960.FIG.9Cshows the bottom rack963and top rack160each comprising two parallel racks, with a corresponding set of opposed tapered pinions961,961′ between them. As shown inFIG.9D, the pinions961are spring-loaded to be biased towards each other by springs969.FIG.9Dshows two pinions960disposed along a common axis968between the trigger930and the housing101of the drive assembly100. Each pinion961includes a spring969biasing the pinion961toward a midline of the device or toward the other pinion. The biasing force of the springs969(shown as arrows990a,990b) can apply an opposing force (shown as arrow991) onto the trigger930and housing101. These opposing force991can urge the housing101upward and the trigger930downward, which can press the guide protrusions106of the housing101and the protrusions970of the handle920into corresponding guide channels262and970, respectively. By biasing these elements together, tolerances can be taken up and rattle created by the device during operation (e.g., when the components are vibrating due to the oscillating blade) can be minimized. These forces can also help maintain the coupling of the pinions961,961′ to the racks160,963.

FIG.9E-9Gare illustrations of another embodiment of a bone and tissue resection device900′ having a handle920′ and a trigger930′ that fits into one or more grooves931formed therein that slide along one or more rails970′ formed in a frame920′ of the stationary assembly902′. The device900′ can function similarly to the device900described above.FIG.9Fis a perspective view of the trigger930′ and its relation to the frame920′.FIG.9Gis a cross-sectional view (taken along plane B ofFIG.9E) showing the trigger930′ coupled to the frame920′ via a pair of opposed protrusions or rails970′ of the frame930′.

FIGS.10A-10Eare illustrations of different embodiments of engagement systems for removably coupling a drive assembly to a stationary assembly.FIG.10Ashows a rack and pinion system for releasably coupling a drive assembly100to a stationary assembly902. The pinion961can be capable of translation (indicated by arrow1095) from a first, locked position1060, where the pinion961is engaged with the top rack106of the housing101of the drive assembly, to a second, release position where the pinion961is disposed below the housing101and clear of the rack160to enable the housing101to be inserted or removed from the frame920of the stationary assembly920.FIG.10Bshows an alternative pinion release mechanism, where a straight pinion1061can be translated laterally (as indicated by arrow1097) to disengage from the rack160, thereby freeing the top rack160and allowing the housing101to be decoupled from the frame920.FIG.10Cshows yet another embodiment of a pinion release mechanism, wherein a pinion1062can be biased with a spring1069against the top rack160of the housing101. To decouple the housing101from the stationary assembly920, a release button1090can be depressed (indicated by arrow1098) to translate the pinion1062laterally against the bias of the spring1069. This translation can disengage the pinion1062from the rack160and clear a path for the rack160(and housing101of the drive assembly) to be translated proximally for decoupling from the stationary assembly902.

FIG.10Dillustrates operation of one embodiment of the latch928shown inFIG.9Bthat can selectively prevent decoupling of the housing101relative to the frame920. In operation, the housing101can be translated distally relative to the frame920until a proximal end thereof, or another proximal-facing surface or other surface feature thereof, contacts the latch mechanism928and deflects latch mechanism928laterally (in the direction of arrow1099) to allow the housing101to pass into the channel of the frame920. Once the housing101is advanced distally a sufficient amount, the latch928can move opposite the arrow1099inFIG.10Dto the position shown in the perspective view ofFIG.10Dand the top view ofFIG.10Ewherein a portion of the latch928interferes with proximal translation of the housing101along the channel in the frame920beyond the position of the latch. To decouple the housing101from the frame920, the latch928can be moved in the direction of arrow1099until, for example, a channel1098formed in the latch aligns with the channel of the frame920along which the housing101translates. In some embodiments, and as shown inFIG.10E, the latch928can include a spring1027that is either separate from or built into the latch928that biases the latch928in the locked position, as shown inFIGS.10D and10E, where the housing101is unable to move proximally in the frame920past the latch928.

Example Longitudinally Extending Trigger Configurations

FIGS.11A-11Care illustrations of one embodiment of a bone and tissue resection device1100having a longitudinally extending handle and trigger arrangement. Such embodiments include alternative handles for the powered cutting systems disclosed herein wherein the handle or trigger is arranged to extend longitudinally along the device. These embodiments can allow for pistol-grip or trigger-like actuation while holding the device1100in a vertical or near-vertical orientation without the need to bend and twist the wrist and arm.

FIG.11Ashows the bone and tissue resection device1100having a stationary assembly1102and a drive assembly100slidably coupled with the stationary assembly1102. The stationary assembly includes a longitudinally extending trigger1129positioned above the drive assembly100and a grip1130integrated into a frame1120disposed around the drive assembly100. In operation, and as shown in more detail inFIG.11B, when the longitudinally extending trigger1129is moved towards the grip1130, a wedge integrated into the trigger1129can contact a roller pin1109coupled to the drive assembly100, thereby advancing the drive assembly100distally.

FIGS.11B and11Cillustrate the inside of the frame1120of the stationary assembly, where the wedge1127of the vertical trigger1129is shown contacting the roller pin1109of an actuation sleeve1108coupled to the drive assembly100. In operation, when the trigger1129moves towards the drive assembly100(as shown by arrow1198inFIG.11C), the roller pin1109is driven along the face1128of the wedge1127, thereby causing the sleeve1108and drive assembly100to advance distally against the biasing force of the spring270. As described above, this distal advancement of the drive assembly100also advances the blade300along the cutting region250to conduct a cutting stroke and resect tissue.

Example Oscillator Mechanisms

FIGS.12A-12Hare illustrations of a drive assembly having a piston oscillator mechanism.FIG.12Ashows an oscillator drive assembly1200having a housing1201that contains a piston oscillator mechanism, a blade shaft shield120extending distally from the housing1201, an input shaft1230to the piston oscillator mechanism extending proximally from the housing101, and a button release181for the blade shaft310(not shown inFIG.12A). The input shaft1230can include a coupling element1231to be engaged by a corresponding element of a motor20to enable the motor20to spin the input shaft1230. In operation, the piston oscillator mechanism converts the input rotational motion of the input shaft1230into an oscillating motion of an output shaft coupled to the blade shaft310, as shown inFIGS.12B-12H.

FIG.12Bshows the components of the oscillator drive assembly1200without the housing1201. The oscillator drive assembly1210includes the input shaft1230, an output shaft1250, and a piston oscillator mechanism coupling the input shaft1230to the output shaft1250, as explained in more detail below. The input shaft1230can rotate freely inside a plurality of bearings1239, bushings, or directly against the housing1201to secure the input shaft1230in the housing1201. The input shaft1230includes a cylindrical eccentric section1232that has a central axis B offset from, and parallel to, the central axis A of the input shaft1230(see dl ofFIG.12E). The input shaft1230can also include a counterweight1233that counterbalances the eccentrically rotating components coupled to the eccentric section1232to reduce or prevent excessive vibration from rotation of the input shaft.

The output shaft1250can also rotate freely inside a plurality of bearings1259, bushing, or directly against the housing1201to secure the output shaft1250in the housing1201. The output shaft1250can be directly coupled to the blade shaft310, or drive a blade coupling to transmit the oscillating torque to the blade shaft310indirectly. This embodiment includes a plurality of collet arms1251that define a central recess to accept a proximal end of a blade shaft310(not shown). A retainer1281is slidably disposed around the collet arms1251and configured to selectively lock the blade shaft (not shown) relative to the output shaft1250as the retainer1281translates relative to the output shaft1250collapsing the collet arms1251towards the blade shaft310. The retainer1281can include an angled face1283that can interface with a corresponding angled face1284of a wedge1280extending towards the retainer. The wedge1280can be moved radially toward or away from the output shaft by actuation of the button release181. Accordingly, in use, a user can depress the button181(i.e., move it in the upward direction ofFIG.12B) to advance the wedge1284radially toward or away from the output shaft1250. This movement of the wedge1284can cause the retainer1281to translate away from the wedging surface of the collet arms1251. As the retainer1281translates, it moves along a portion of the collet arms1251having a tapered diameter such that the retainer exerts less compressive pressure on the collet arms1251. In this state a user can insert or remove a proximal end of a blade shaft310due to the reduced grip of the collet arms1251. Upon release of the button181, the wedge1280can move radially away from the output shaft1250, resulting in the translation of the retainer1281towards the wedging surface of the collet arms1251that can urge the collet arms1251against any blade shaft disposed therebetween. This can lock the blade shaft, if present, to the output shaft1250.

Turning to the piston oscillator mechanism that couples the input shaft1230to the output shaft1250,FIG.12Bshows a connector1240disposed concentrically around a bearing1242(seeFIG.12D) that is disposed around the eccentric section1232of the input shaft1230. The output shaft1250has a stationary pin1241either integrated into the output shaft1250or as a separate component extending therefrom into a bore1255formed in the output shaft. In operation, rotation of the input shaft1230can spin a central axis A (seeFIG.12E) of the eccentric section1232about the central axis B (seeFIG.12E) of the input shaft1230, which is offset from the central axis of the eccentric section1232by a distance dl (seeFIG.12E). The eccentric rotation of the connector1240driven by the eccentric section1232moves the connector over the pin1241with respect to a central axis C of the output shaft1250(seeFIG.12B) in a manner similar to a piston connector rod being moved up and down by a crankshaft in an internal combustion engine. As the input shaft1230rotates, the angular position of the central axis B of the eccentric section1232of the input shaft moves relative to the central axis C of the output shaft1250creating an oscillation about the central axis C. Repeated rotations of the input shaft1230therefore cause repeated oscillating movement of the output shaft1250about its central axis C. The range of the oscillating motion is shown in more detail inFIGS.12G and12H, which provide an end-view of the shafts1230,1250and connector1240. In some embodiments, the pin1241can be integral to the connector1240, and the output shaft1250will feature a bore for the pin1241to move within to create the oscillation.

FIG.12Cshows a detail view of the input shaft1230, output shaft1250, connector1240, and spacer1258. Note that in the perspectives of each ofFIGS.12B and12C, the input shaft is rotationally orientated such that the central axis B of the input shaft1230(seeFIG.12E) is aligned with the central axis A of the eccentric section1232(seeFIG.12E).FIG.12Dis a perspective view of the components shown inFIG.12C. Visible in the perspective view is the bearing1242disposed inside the connector1240that allows the eccentric section1232to spin inside the connector1240. In some cases, the bearing1242can be a bushing, or the connector can be directly contacting the eccentric section1232.FIG.12Dalso shows the pin1241extending from the bore1255in the output shaft1250. In some embodiments, and as shown, the bore1255is a hole through the output shaft1250that is orthogonal to the output shaft's axis of rotation C.FIG.12Fis a detail view without the spacer1258.

FIGS.12G and12Hillustrate the conversion of rotational motion of the input shaft1230into oscillating motion of the output shaft1250.FIGS.12G and12Heach show the piston oscillator mechanism in a view orthogonal to the central axes B, C of the input shaft1230and the output shaft1250, respectively. Horizontal (H) and vertical (V) axes are labeled in both figures (though these terms are relative, as rotating the instrument can reorient which axis is vertical vs. horizontal), and the intersection of the horizontal and vertical axes is placed at the central axis of rotation B of the input shaft1230. Also shown in the figure is the central axis A of the eccentric section1232. The intersection of the vertical axis with a second horizontal axis1299is the central axis C of the output shaft1250. In operation, the input shaft1230spins, clockwise or counterclockwise, and the output shaft1250oscillates clockwise and counterclockwise between the positions shown inFIG.12GandFIG.12H. The difference between these positions therefore represents the range of oscillation of the output shaft1250.

InFIG.12G, the eccentric section1232is maximally extended in a first horizontal direction (e.g., to the left with respect toFIG.12G) and the pin1241has rotated the output shaft1250clockwise by an angle represented by the angular relation of a reference line1281with respect to the second horizontal axis1299. The reference line1281is chosen to be perpendicular with the second horizontal axis1299when the eccentric section1232is maximally extended in either vertical direction (e.g., up or down with respect toFIG.12G). The angular difference between line1299and1281inFIG.12Gis a maximum clockwise the rotation of the output shaft1250induced by the rotation of the eccentric section1232about which the connector1240is disposed.

FIG.12Hillustrates the eccentric section1232maximally extended in a second horizontal direction (e.g., to the right with respect toFIG.12G) opposite the first direction shown inFIG.12G. InFIG.12H, the pin1241has rotated the output shaft1250counterclockwise by an angle represented by the angular relation of the reference line1281with respect to the second horizontal axis1299. The angular difference between line1299and1281inFIG.12His maximum counterclockwise the rotation of the output shaft1250induced by the rotation of the eccentric section1232about which the connector1240is disposed.

The angular range of oscillation shown inFIGS.12G and12Hcan be adjusted by, for example, adjusting various geometric parameters of the assembly. For example, adjusting the eccentric section to increase or decrease the distance dl between the central axis B of the input shaft1230and the central axis A of the eccentric section1232can adjust the angular range of oscillation. Similarly, adjusting a distance between input and output shafts1230,1250, respectively, can influence the angular range of oscillation. Generally speaking, the above-described configuration can be well suited to applications that require a smaller angular range of oscillation at a higher rate of oscillation. By way of example only, the total angular range of oscillation shown inFIGS.12G and12Hcan be less than about 10° in some embodiments. In some embodiments, the total angular range can be about 7°.

The piston oscillator mechanism ofFIGS.12A-12Hhas a number of advantages over known oscillators. For example, the piston oscillator mechanism can convert high input RPMs (revolutions per minute) into high output OPMs (oscillations per minute) due to low friction and backlash generated during the movements of the piston oscillator mechanism. For example, the input shaft1230can be counter balanced such that rotation of the connector1240and pin1241generate minimal vibration, and the movement of the pin1241in the bore1255is the only point of contact between moving parts outside of the bearings. In some embodiments, the pin and/or the bore1255can be made formed of, or coated with, a material having low friction, or the pin1241and/or the bore1255can be lubricated to further reduce friction. Further, in some embodiments, the bore1255can be lined with a sleeve or insert that can aid in reducing frictional forces. Exemplary rotation and oscillation rates can be quite high, e.g., as high as about 80,000 OPM in some embodiments. Operating at such high oscillation rates can enable superior cutting performance from the blade300or other instrument coupled to the output shaft1250.

FIGS.13A-13Fare illustrations of an oscillator drive assembly1300having a four bar linkage oscillator.FIG.13Ashows the oscillator drive assembly1300with a housing1301that contains that an input shaft1330, an output shaft1350, and a four bar linkage oscillator that connects the input shaft1330to the output shaft1350. The input shaft1330extends proximally from the housing1301of the drive assembly1300with a coupling element1331that can be engaged by a corresponding element of a motor20(not shown) to enable the motor20to spin the input shaft1330. The output shaft1350can be configured to couple with a blade shaft310(not shown) such that oscillations of the output shaft1350are transferred to the blade shaft310. The four-bar linkage oscillator can couple an offset or eccentric section of the continuously spinning input shaft1330to the output shaft1350by means of a linkage1340. The input shaft1330can be rotatably secured in the housing1301by bearings1339, bushings, or directly contacting the housing and can include an eccentric section1332with a counterweight1333. Further, the output shaft1350can include collet arms1355disposed at a distal end thereof, as well as a translating retainer1304that can selectively lock a blade or other instrument shaft between the collet arms1355in a manner similar to the retainer1281described above. In some embodiments, the output shaft1350can be directly coupled to the blade shaft310. In some embodiments, the output shaft1350can be indirectly coupled to the blade shaft310through means of a temporary mechanical, or magnetic connection. In some embodiments, the offset pin1341can be directly coupled to, or part of the blade shaft310to minimize reciprocating mass.

FIGS.13B and13Cshow the moving components of the four-bar linkage oscillator drive assembly1300without the housing1301, bearings1339, bushings1302,1303, or retainer1304. In operation, the output shaft1350oscillates as the central axis of the eccentric section1332moves close to and then away from the central axis of the output shaft1350. The linkage1340is connected to the eccentric section1332by a bearing1342, bushing, or direct contact to the eccentric section1332at one end and to an offset pin1341coupled to the output shaft1350at an opposite end of the linkage1340by a bearing, bushing, or direct contact. In some embodiments, the offset pin1341is part of the linkage1340and travels inside a bearing, bushing, or direct contact offset from the central axis of the output shaft1350.

FIGS.13D-13Fshow the motion of the four bar linkage oscillator1310as it converts the clockwise rotational motion of the input shaft1330(arrows1390) to oscillating motion of the output shaft1350(arrows1394,1396). InFIGS.13D-13F, the intersections of the first horizontal (H1) axis with the vertical (V) axis (as noted above, horizontal and vertical are relative terms depending on an orientation of the device) represent the central axis of rotation B of the input shaft1330, and the intersections of the second horizontal axis (H2) with the vertical (V) axis represent the central axis of rotation C of the output shaft1350. InFIG.13D, the eccentric section1332is minimally extended in the vertical direction away from the output shaft1350(in other words, the central axis A of the eccentric section1332is rotated to a position where it is disposed a maximum distance away from the output shaft1350), which represents a near maximum oscillation of the output shaft1350in the counterclockwise direction (as indicated by arrow1394). This oscillation is represented by an angular deviation of a reference line1398through the center of output shaft1350that is chosen such that the reference line1398aligns with the vertical axis V between the maximum and minimum oscillation points, as shown inFIG.13E. AsFIG.13Drepresents the near maximum counterclockwise oscillation of the output shaft1350, continued clockwise rotation1390of the input shaft1330eventually moves the eccentric section1332vertically towards the output shaft1350, which rotates the offset pin1341and the output shaft1350clockwise about the central axis C of the output shaft1350, as shown inFIG.13E.

FIG.13Erepresent about 90 degrees of clockwise rotation1390of the eccentric section1332from the position ofFIG.13D. Continued rotation of the input shaft1330rotates the eccentric section to a near maximum vertical position, as shown inFIG.13F, where a central axis A of the eccentric shaft1332is closest to the output shaft1350and the linkage1340has been driven upwards (in the plane ofFIG.13F). This motion of the linkage1340can rotate the input shaft1350clockwise to a maximum oscillation in the clockwise direction (as indicated by arrow1396). Continued rotation of the input shaft1330rotates the eccentric shaft1332to move the linkage1340away from the output shaft1350and induces counterclockwise rotation in the output shaft1350. Therefore, as the input shaft1330spins, the output shaft1350oscillates between the positions shown inFIGS.13D and13F. The ratios between the distances between the pivot points can change the amplitude of this oscillation (e.g., changing the offset distance between the central axis of the input shaft1330and eccentric section1332, the length of the linkage1340, the offset of the pin1341, etc.).

The four bar linkage oscillator can also provide advantages over known oscillators. For example, in comparison to a traditional Scotch yoke the four bar linkage oscillator lacks a bearing that slaps between sides of a yoke, which can fatigue the yoke and radially impact a bearing on the offset shaft. Thus, in traditional Scotch yoke, as the RPM/OPM increases the likelihood for fatigue of the yoke and bearing wear on the offset shaft increases. The four bar linkage oscillator, in contrast, has only rotational bearing surfaces that remain in contact at all times, allowing for improved durability and more predictable wear. In some embodiments, the linkage1340can be made of a bearing grade material, thereby negating the need for a separate bearing between the linkage1340and either of the offset pin1341and/or the eccentric section1332of the input shaft1330.

In comparison to the piston oscillator described above, the four bar linkage can in some embodiments be configured to provide a greater angular range of oscillation, but may not be capable of operating at the very high speeds achievable with the piston oscillator. For example, in some embodiments the range of angular oscillation for the four bar linkage oscillator can be up to about 40°. In the illustrated embodiment, the range of angular oscillation can be about 31°.

In some embodiments, the output shaft1250or1350or blade shaft310can also be forced to oscillate axially about their axis of rotation in order to improve debris clearing during the cutting operation. This axial motion can be created through use of a cam mechanism to drive the output shaft1250or1350or blade shaft310proximally and distally during the course of a single stroke.

Alternative Configurations

FIG.14is an illustration of one embodiment of a bone and tissue resection device having an alternative longitudinally extending grip arrangement.FIG.14shows the bone and tissue resection device1400includes a drive assembly100and a stationary frame1420around the drive assembly100and a disposable shield assembly220temporarily attached to the stationary frame1420. The stationary frame1420includes an attachment beam1428for connecting a coupling element1401of the shield assembly220and preventing rotation of the shield assembly220with respect to the stationary frame1420. The coupling element1401includes a clip feature at one end thereof that engages with the attachment beam1428by being rotated around the shield assembly220. The stationary frame1420has a grip1429disposed around the stationary frame1420and shaped to allow a user to grasp the stationary frame1420in their hand, with their thumb resting against the thumb trigger190of the drive assembly100. In some embodiments, the stationary frame1420is connected to the oscillator assembly100and cannot be removed from the oscillator assembly100. In some embodiments, the stationary frame1420can be separated from the oscillator assembly100allowing the user to handle the oscillator assembly100directly. In some embodiments, a spring can be used to retract the blade300inside of the disposable shield assembly220.

FIG.15is an illustration of a bone and tissue resection device having yet another alternative longitudinally extending grip arrangement. The bone and tissue resection device1500includes a drive assembly100and a stationary frame1520around the drive assembly100and a disposable shield assembly220attached to the stationary frame1520. The stationary frame1420includes a coupling1528for connecting the shield assembly220. In some embodiments, the shield assembly220is integral to the stationary frame1520. The stationary frame1520has a grip1529disposed around the stationary frame1520and shaped to allow a user to grasp the stationary frame1520in their hand, with their thumb resting against the thumb trigger190of the drive assembly100. The stationary frame1520includes a spring270that biases the drive assembly100in the proximal direction and against, for example, the user's force against the thumb trigger190to move the drive assembly100in the distal direction and translate the blade300through the cutting region250at the distal end of the shield assembly220.

FIG.16is an illustration of a bone and tissue resection device having a thumb-actuated trigger. The bone and tissue resection device1600includes a stationary assembly1620and a drive assembly100slidably engaged directly or indirectly with a frame1621of the stationary assembly1620. A shield assembly220is attached to the stationary assembly with an offset elongated arm1601that engages with a coupler1628on the frame1621to retain the shield assembly220in place. The elongated arm1601extends radially from the shield assembly to increase the ability of the coupler1628to prevent rotation of the elongated tube221of the shield assembly if any rotational energy is transferred to the footplate222during use. In some embodiments, a spring can be used to retract the blade300inside of the disposable shield assembly220.

The frame1621of the stationary assembly includes an integrated handle1629shaped to be grasped by a user's hand, with their thumb against the thumb trigger190of the drive assembly100to actuate the movement of the drive assembly100with respect to the frame1621. In some embodiments the shape fills the palm to enable the user to guide the footplate222with their hand but leaves the thumb free to advance the oscillator assembly100. Here, the frame1621surrounds the thumb trigger190such depressing the thumb trigger distally to move the drive assembly100advances the thumb trigger190toward the stationary assembly1620. In some embodiments, the thumb trigger190being recessed into the frame1621can further secure the position of the user's thumb against the thumb trigger190and prevent a user's finger from being pinched or trapped between the trigger190and the stationary housing1620. In some embodiments, the bone and tissue resection device1600can include a powered actuation mechanism to move the drive assembly100, and the thumb trigger190can be a button that the user engages to control the powered actuation mechanism to move the drive assembly100distally or proximally. In some embodiments, the powered actuation mechanism can move the drive assembly100proximally when the thumb trigger190is released.

In some embodiments the feature a user presses to advance the blade300towards the footplate222to cut can activate the motor that causes the oscillator assembly100to oscillate.

Coring Saw Device Examples

FIGS.17A and17Bare illustrations of a bone and tissue resection device1700having a rotating coring saw blade1731. A continuously spinning coring saw can be nested inside a housing with an opening to allow the blade to be exposed to the tissue to be cut.FIG.17Ashows a shield sleeve1721fixedly attached to a handle1791and a drive assembly1710slidably attached to the handle1791. The drive assembly1710can be configured to be coupled with a motor20and a coring blade1731. The drive assembly1710can include a thumb trigger1790for pushing the drive assembly1710distally using the thumb of a user's hand that is holding the handle1791. The shield sleeve1721can include an open distal end1722and one or more cutting region(s)250through which the coring blade1731passes as it is driven distally by the drive assembly being advanced with respect to the shield sleeve1721.FIG.17Bshows the bone and tissue resection device1700with the blade1731attached. While shown with an open distal end1722, in some embodiments the shield sleeve1721can have a closed end. In some embodiments, the shield sleeve1721can be detached from the handle to allow for a variety of shield options to be used. In some embodiments, the drive assembly1710can be advanced through means of a manual squeeze style trigger or automated through use of an actuator to drive the motion forward and backward. In some embodiments, the drive assembly1710can have a spring to return the blade1731to the starting position.

Counter-Rotating Blade Examples

FIG.18is an illustration of a counter-rotating blade device1800for use with an oscillating drive assembly, such as the drive assembly100ofFIG.1.FIG.18shows the counter-rotating blade device1800includes a distal end with dual counter rotating blades1821,1822with either toothed or diamond grit ends1831,1832. The counter-rotating blade device1800includes a coupling mechanism1938at a proximal end for coupling the counter-rotating blade device1800with the output of an oscillating drive assembly. In operation, counter rotation stabilizes the blades1821,1822to ensure maximum cutting efficiency. In some embodiments, the counter rotation of the blades1821,1822can be driven through use of a planetary gear mechanism1811attached to the coupling mechanism1838. In some embodiments, the counter rotation of the blades1821,1822can be driven through two separate oscillating mechanisms.

Alternative Depth Adjustment Mechanism Arrangements

FIGS.19A and19Bare illustrations of one embodiment of a bone and tissue resection device1900with a depth adjustment mechanism1901for adjusting the position of a blade300by translating a drive assembly100. The bone and tissue resection device1900includes a stationary assembly200with a shield assembly220extending to a cutting region250proximal to a footplate420at the distal end of the shield assembly220. The bone and tissue resection device1900also includes a drive assembly100configured to move with respect to the stationary assembly200, the drive assembly100including a blade shaft310extending distally from the drive assembly100to a blade300through a blade shaft shield120. The depth adjustment mechanism1901is configured to move the drive assembly100along a proximal-distal axis of the bone and tissue resection device1900, whereby the movement of the drive assembly100causes the blade300to move through the cutting region250at the distal end of the shield assembly220.FIG.19Ashows the bone and tissue resection device1900with the drive assembly100in a proximal position with the blade300retracted from the cutting region250. InFIG.19B, the depth adjustment mechanism1901has moved the drive assembly1901distally until the blade300has crossed the entire cutting region250.

FIGS.20A and20Bare illustrations of one embodiment of a bone and tissue resection device2000with a depth adjustment mechanism2001is configured to adjust the axial position of the blade300with respect to the cutting region250without adjusting the axial position of the drive mechanism100. The depth adjustment mechanism2001is configured to move the blade300and blade shaft310with respect to the drive assembly100along a proximal-distal axis of the bone and tissue resection device3000, whereby the depth adjustment mechanism2001causes the blade300to move into and out of the cutting region250at the distal end of the shield assembly220.FIG.20Ashows the bone and tissue resection device2000with the blade300and blade shaft310in a proximal position with the blade300retracted from the cutting region250. InFIG.20B, the depth adjustment mechanism2001has moved the blade300distally until the blade300has crossed the entire cutting region250.

FIGS.21A and21Bare illustrations of one embodiment of a bone and tissue resection device2100with a depth adjustment mechanism2102that includes handle2101configured to be operated by a user to apply a force to advance a blade300through a cutting region250. In operation, as shown inFIG.22A, the depth adjustment mechanism2102can, for example pivot about a point2103in the bone and tissue resection device2100such that the force applied to the handle2101by the user in a servers to rotate the handle2101about the pivot point2103, as shown by arrow2104. In rotation, the handle2101drive the depth adjustment mechanism2102distally against the drive assembly100, which moves the blade300through the cutting region250, as shown inFIG.22B. In other embodiments, the drive assembly100is stationary depth adjustment mechanism2102is configured to drive the blade300through the cutting region250and the blade300and the blade shaft310move with respect to the drive assembly100.

FIGS.22A and22Bare illustrations of one embodiment of a bone and tissue resection device2200with a powered depth adjustment mechanism2201operable to adjust the position of a blade300with respect to a cutting region250. The bone and tissue resection device2200includes a trigger2202configured to be operable by a user holding the bone and tissue resection device2200. The trigger2202is configured to send a signal via a control wire2203to the depth adjustment mechanism2201.FIG.22Ashows the depth adjustment mechanism2201is coupled to the drive assembly100in order to move the drive assembly100along a proximal-distal axis and thereby move the blade300into and out of the cutting region250. In some embodiments, the depth adjustment mechanism2201can move the drive assembly100distally when a user engages the trigger2202and then move the drive mechanism100proximally when the user releases the trigger2202. In other embodiments, the trigger2202can be configured to be operable in more than one direction, such that the user can actively control both the distal and proximal movement of the blade300in the cutting region250. In some embodiments, the depth adjustment mechanism2201includes an electric motor. In some embodiments, the drive assembly100is not driven by the depth adjustment mechanism2201, and instead the depth adjustment mechanism2201moves the blade300with respect to the drive assembly100.

It should be noted that any ordering of method steps expressed or implied in the description above or in the accompanying drawings is not to be construed as limiting the disclosed methods to performing the steps in that order. Rather, the various steps of each of the methods disclosed herein can be performed in any of a variety of sequences. In addition, as the described methods are merely exemplary embodiments, various other methods that include additional steps or include fewer steps are also within the scope of the present disclosure.

The instruments disclosed herein can be constructed from any of a variety of known materials. Exemplary materials include those which are suitable for use in surgical applications, including metals such as stainless steel, titanium, nickel, cobalt-chromium, or alloys and combinations thereof, polymers such as PEEK, ceramics, carbon fiber, and so forth. The various components of the instruments disclosed herein can have varying degrees of rigidity or flexibility, as appropriate for their use. Device sizes can also vary greatly, depending on the intended use and surgical site anatomy. Furthermore, particular components can be formed from a different material than other components. One or more components or portions of the instrument can be formed from a radiopaque material to facilitate visualization under fluoroscopy and other imaging techniques, or from a radiolucent material so as not to interfere with visualization of other structures. Exemplary radiolucent materials include carbon fiber and high-strength polymers.

The devices and methods disclosed herein can be used in minimally-invasive surgery and/or open surgery. While the devices and methods disclosed herein are generally described in the context of spinal surgery on a human patient, it will be appreciated that the methods and devices disclosed herein can be used in any of a variety of surgical procedures with any human or animal subject, or in non-surgical procedures.

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

The devices described herein can be processed before use in a surgical procedure. First, a new or used instrument can be obtained and, if necessary, cleaned. The instrument can then be sterilized. In one sterilization technique, the instrument can be placed in a closed and sealed container, such as a plastic or TYVEK bag. The container and its contents can then be placed in a field of radiation that can penetrate the container, such as gamma radiation, x-rays, or high-energy electrons. The radiation can kill bacteria on the instrument and in the container. The sterilized instrument can then be stored in the sterile container. The sealed container can keep the instrument sterile until it is opened in the medical facility. Other forms of sterilization known in the art are also possible. This can include beta or other forms of radiation, ethylene oxide, steam, or a liquid bath (e.g., cold soak). Certain forms of sterilization may be better suited to use with different portions of the device due to the materials utilized, the presence of electrical components, etc.

One skilled in the art will appreciate further features and advantages of the disclosure based on the above-described embodiments. Accordingly, the disclosure is not to be limited by what has been particularly shown and described. All publications and references cited herein are expressly incorporated herein by reference in their entirety.