Cutting accessory for a powered surgical cutting instrument

Abstract

A cutting accessory for a surgical cutting instrument. The cutting accessory includes an outer hub, an outer tube (68), and a drive tube coaxially and rotatably disposed within the outer tube. The drive tube may include geometries for transmitting torque along or about a bend. A shank (88) is coupled to the drive tube and defines an annular recess (98). The cutting accessory includes means (80) for preventing axial movement or deflection of the cutting tip (72) relative to the outer tube (68). The means may be a retention feature or member formed with or secured to the outer tube (68), and disposed within the annular recess (98) of the shank. At least one tab may be formed by a slot (104) of the outer tube (68), and deflected inwardly into the annular recess. The retention member (80) may facilitate complementary translation of the drive tube and the outer tube to provide a microdebrider cutting accessory with an adjustable working length.

Description

CUTTING ACCESSORY FOR A POWERED SURGICAL CUTTING INSTRUMENTCROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority and all the benefits of United States Provisional Patent Application No. 63 / 689,023, filed on August 30, 2024, the entire contents of which are hereby incorporated by reference.BACKGROUND

[0002] Powered cutting instruments are widely used in surgical procedures to resect bone and other tissue. The surgical cutting instrument may include a powered handpiece including a motor, and a cutting accessory removably coupled to the handpiece. Based on the nature and type of the surgical procedure, a surgeon may select a cutting accessory with the desired characteristics from a catalogue of cutting accessories. Of particular interest are burs in which a bur head is couped to a drive shaft and rotated, often at high speeds, relative to an outer tube to resect tissue in difficult-to-access anatomy, such as the ear, nose, and throat (ENT). The drive shaft may be a drive tube defining a lumen for aspiration of fluids and debris from the surgical site.

[0003] Often, the cutting accessory for ENT procedures includes at least one bend. The bend angle may be fixed, or the bend angle may be selectively adjustable through articulation or manual bending of the outer tube. As a result, the drive tube rotating therein must transmit torque along or about the bend. One manner of doing so is disclosed in commonly-owned International Publication No. WO2022 / 123535, published June 16, 2022, the entire contents of each being hereby incorporated by reference, in which a flexible region of the drive tube includes interlocking geometries defining slots (e.g., a spiral cut pattern). With the bur head extending from the drive tube and positioned distal to the outer tube, the spiral cut pattern may result in axial deflection of the bur head with high-speed rotation. In other words, the slots may widen slightly due to distal forces on the bur head. Even if relatively minor in magnitude, the axial deflection may undesirably result in suboptimal accuracy with visualization of the cutting tip with a surgical navigation system. Moreover, the axial deflection may render more difficult “back cutting,” a surgical technique used to protect anatomical structures by resecting with a proximal portion of the bur head. Because back cutting applies a distal force to the proximal surface of the bur head, thesedistal forces may move the bur head distally if the cutting tip is not sufficiently retained. Similarly, with a drive shaft that is solid in section, axial movement due to forces to the bur head may have negative effects on the opposing end at an interface between the drive shaft and the motor. Therefore, there is a need in the art for an improved cutting accessory for a powered surgical cutting instrument in which axial movement or deflection of the cutting tip is minimized or eliminated.

[0004] Another cutting accessory of particular interest is a microdebrider in which the outer tube defines a cutting window, and the drive tube defines a cutting edge that is rotated therein to shear or debulk the tissue. Often, a working length of the cutting accessory is specifically designed to access certain anatomy. Nearby anatomy - often despite being only a few centimeters (cm) away - remains inaccessible for that selected microdebrider cutting accessory. For example, a microdebrider cutting accessory with a working length of 11 cm may be appropriate for an ethmoidectomy, but the microdebrider cutting accessory may require a 13 cm working length for debriding the more posterior sphenoid sinuses. As a result, when moving between these two anatomical regions, the surgeon may have to undesirably pause the surgical aspect of the surgical procedure to replace the cutting accessory. Therefore, there is a further need in the art for a microdebrider cutting accessory with an adjustable working length, wherein procedure time may be reduced and fewer disposable components used, thereby improving efficiency, minimizing expense, and reducing waste.SUMMARY

[0005] The present disclosure is directed to a cutting accessory for a surgical cutting instrument in which a retention member or retention feature prevents axial movement or deflection of a cutting tip. The cutting accessory includes a hub configured to be removably coupled to a handpiece of the powered surgical instrument, and a tube assembly extending from the hub. The tube assembly includes an outer tube, and a drive shaft coaxially disposed within the outer tube. The drive shaft may be solid in section, or a drive tube. The drive tube may include geometries configured to provide flexibility to the drive tube. The retention member may be secured to outer tube and operably coupled to the cutting tip. The retention member may be formed from poly ether ether ketone (PEEK) or other suitable polymeric, metallic, or composite material. A sheath may be disposed over at least a portion of the outer tube including the retention member.

[0006] In certain implementations, the cutting tip includes a shank coupled to a distal end of the drive shaft. The shank defines an annular recess, and the outer tube may define a slot, axially aligned with the annular recess of the shank. The retention member is secured within the slot through welding, press fit, friction fit, interference fit, and / or an overlying sheath so as to be disposed within the annular recess of the shank. The retention member may arcuate and may include an outer surface that is contoured to an outer surface of the outer tube. One or more ribs may be positioned within the annular recess of the shank to provide bearing surfaces with rotation of the cutting tip. The ribs may be circumferentially spaced apart from one another to voids therebetween for irrigating fluid to flow pass the retention member. The retention member may include a mounting head, and an engagement portion extending from the mounting head. The mounting head is sized complementary to the slot of the outer tube, and the engagement portion is arcuate and disposed within the annular recess of the shank. The mounting head may include a chamfer that is contoured to a chamfer associated with a distal end of the outer tube, and / or tabs configured to engage geometries of the slot of the outer tube. One or more channels may be defined by the engagement portion.

[0007] In certain implementations, the slot of the outer tube is optional, and the outer tube defines an inner annular recess axially aligned with the annular recess of the shank. The retention member may be one or more clips with a collective length approximating a length of the annular recess of the shank. The clips may be deflectable to be resiliently expanded to be directed over and onto the shank, and resiliently compressed to be directed through the distal end of the outer tube.

[0008] In certain implementations, the retention member is press fit against the inner surface of the outer tube. The retention member may include two clamshells configured to interlock with one another. Another variant includes opposing wings, and a mounting head disposed between the wings. Each of the wings is arcuate and contoured to the inner surface of the outer tube to be press fit. The mounting head is angled upwardly in a distal direction and separated from the wings by slots. A material zone adjacent the slot may provide for the wings flexing outwardly to couple to the shank of the cutting tip, and flexing inwardly to facilitate assembly the press fit arrangement within the outer tube. The mounting head is cantilevered to permit flexion during assembly, in particular to resiliently flex outwardly to within the slot after insertion through the distal end of the outer tube.

[0009] In certain implementations, the retention feature of the outer tube. The outer tube defines a slot shaped to provide at least one tab. The tabs may be diametrically opposite one another, or at any suitable radial offset about the axis of the outer tube. The tabs are axially aligned with the annular recess of the shank. The tabs are deflected inwardly to be disposed within the annular recess of the shank. A sheath may be disposed over at least a portion of the outer tube including the slots. The slot may be dimensioned sufficiently small so as to minimize egress of irrigation fluid therethrough. A distal portion and a proximal portion of the slot may be oriented circumferentially. A middle portion of the slot may be oriented longitudinally between the distal and proximal portions. Corners of the intersections between the portions may be rounded. The outer tube may undergo a case hardening process. Additionally or alternatively, a lubricant may be disposed between the outer tube and at least the cutting tip. In another variant, the tabs are arranged circumferentially about the distal end of the outer tube and deflected inwardly to an angle approximating the taper of the neck of the cutting tip.

[0010] Another aspect the present disclosure is directed to providing a microdebrider cutting accessory with an adjustable working length. The retention member is coupled to the outer tube, and may be any of the implementations of the retention member disclosed herein. The drive tube includes driven features on a proximal portion of the drive tube. The microdebrider cutting accessory includes a telescoping drive coupler engaging the driven features of the drive tube. The telescoping drive coupler is configured to permit for adjustment of the working length of the tube assembly. The telescoping drive coupler includes the drive hub coupled to the drive tube and including at least one spline or interfacing geometry configured to be operably coupled with a complementary geometry of the motor with the outer hub coupled to the handpiece. A cannulated rotor is coupled to the drive hub and includes drive features configured to engage the driven features of the drive tube. The drive and driven features may be complementary splines. The splines of the drive feature may be disposed on an inner diameter of the cannulated rotor, and the splines of the driven features may be disposed on an outer diameter of the drive tube.

[0011] The outer hub may define an internal cavity, and a stop feature may be coupled to the outer tube and movable within the internal cavity. The outer hub may define a seal cavity, and a dynamic seal may be disposed within the seal cavity. A locking mechanism is coupled to the outer hub to permit the cutting accessory to be actuated or moved between locked and unlocked states. The locking mechanism may be a dial defining a cavity including internal threadsconfigured to engage external threads of the outer hub. The dial also includes compression tabs disposed within the cavity and configured to be deflected by projections of the outer hub to engage the outer tube by friction force in the locked state. The cutting accessory may include an actuator coupled to the outer hub and operably coupled to the outer tube. The actuator is configured to receive a user input to cause translation of the outer tube relative to the telescoping drive coupler.

[0012] Additional advantages of the cutting accessory will be readily appreciated in view of the written description and accompanying figures disclosed herein.BRIEF DESCRIPTION OF THE DRAWINGS

[0013] FIG. 1 is a perspective view of a powered surgical cutting instrument. A cutting accessory is removably coupled to a handpiece. The cutting accessory includes an outer hub, a tube assembly extending from the hub, and a retention member.

[0014] FIG. 2 is a detailed view of the tube assembly within circle 2 of FIG. 1. A portion of an outer tube of the tube assembly is removed to depict a flexible region of the drive tube.

[0015] FIG. 3 is an exploded view of a distal portion of the cutting accessory including a cutting tip, the outer tube, and a first implementation of the retention member.

[0016] FIG. 4 is a perspective view of the retention member of FIG. 3.

[0017] FIG. 5 is an axial sectional view of the distal portion of FIG. 3 in which the retention member is coupled to the outer tube.

[0018] FIG. 6 is an elevation sectional view of the distal portion of FIG. 3 in which the retention member is coupled to the outer tube.

[0019] FIG. 7 is an exploded view of a distal portion of the cutting accessory including a cutting tip, the outer tube, and a second implementation of the retention member.

[0020] FIG. 8 is a perspective view of the retention member of FIG. 7.

[0021] FIG. 9 is an axial sectional view of the distal portion of FIG. 7 in which the retention member is coupled to the outer tube.

[0022] FIG. 10 is an elevation sectional view of the distal portion of FIG. 7 in which the retention member is coupled to the outer tube.

[0023] FIG. 11 is an exploded view of a distal portion of the cutting accessory including a cutting tip, the outer tube, and a third implementation of the retention member.

[0024] FIG. 12 is a perspective view of the retention member of FIG. 11.

[0025] FIG. 13 is an axial sectional view of the distal portion of FIG. 11 in which the retention member is coupled to the outer tube.

[0026] FIG. 14 is an elevation sectional view of the distal portion of FIG. 11 in which the retention member is coupled to the outer tube.

[0027] FIG. 15 is an exploded view of a distal portion of the cutting accessory including a cutting tip, the outer tube, and a fourth implementation of the retention member.

[0028] FIG. 16 is a perspective view of the retention member of FIG. 15.

[0029] FIG. 17 is an axial sectional view of the distal portion of FIG. 15 in which the retention member is coupled to the outer tube.

[0030] FIG. 18 is an elevation sectional view of the distal portion of FIG. 15 in which the retention member is coupled to the outer tube.

[0031] FIG. 19 is an exploded view of a distal portion of the cutting accessory including a cutting tip, the outer tube, and a fifth implementation of the retention member.

[0032] FIG. 20 is a perspective view of the retention member of FIG. 19.

[0033] FIG. 21 is an axial sectional view of the distal portion of FIG. 19 in which the retention member is coupled to the outer tube.

[0034] FIG. 22 is an elevation sectional view of the distal portion of FIG. 19 in which the retention member is coupled to the outer tube.

[0035] FIG. 23 is a perspective view of the distal portion of the cutting accessory including a sixth implementation of the retention member in which pins are coupled to the tube assembly and shown prior to machining.

[0036] FIG. 24 is sectional elevation view of the retention member of FIG. 23 in which the pins have been machined to be contoured to or flush with the outer tube.

[0037] FIG. 25 is a perspective view of a seventh implementation of the retention member.

[0038] FIG. 26 is a perspective view of the distal portion of the cutting accessory including the retention member of FIG. 25.

[0039] FIG. 27 is an elevation sectional view of the distal portion of FIG. 25 in which the retention member is coupled to the outer tube.

[0040] FIG. 28 is a perspective view of an eight implementation of the retention member.

[0041] FIG. 29 is an elevation sectional view of the distal portion of FIG. 28 in which the retention member is coupled to the outer tube.

[0042] FIG. 30 is a perspective view of the distal portion of the cutting accessory including a ninth implementation of the retention member, which is a retention feature of the outer tube.

[0043] FIG. 31 is a perspective view of the distal portion of the cutting accessory including a tenth implementation of the retention member, which is a retention feature of the outer tube.

[0044] FIG. 32 is a perspective view of a microdebrider cutting accessory in which a working length of the tube assembly is adjustable. A locking mechanism is operably coupled to the outer hub and the outer tube.

[0045] FIG. 33A shows the locking mechanism in a locked configuration.

[0046] FIG. 33B shows the locking mechanism in an unlocked configuration.

[0047] FIG. 34 is an elevation sectional view of the cutting accessory of FIG. 32 taken along lines 34-34.

[0048] FIG. 35 is a detailed view of a portion of the cutting accessory of FIG. 34 with box 35-35.DETAILED DESCRIPTION

[0049] FIG. 1 shows a surgical cutting instrument 40 including a handpiece 42, and a cutting accessory 44 configured to be removably coupled to the handpiece 42. The handpiece 42 is a capital component; i.e., a component configured to be sterilized and reused over many surgical procedures. The cutting accessory 44 may be disposed of after a single use, or it may be manufactured to be sterilizable and reusable. Alternatively, the handpiece 42 and the cutting accessory 44 may be integrally formed and not detachable from one another.

[0050] The handpiece 42 is contoured for ergonomic grasping and manipulation. The handpiece 42 includes a power port or power cord 46, and, optionally, a suction port 48 and an irrigation port 50. A motor (not shown) within the handpiece 42 is driven by power transmitted through the power cord 46 removably coupled to a power source. The power source may be asurgical console, for example, a powered instrument driver sold under the tradename CORE by Stryker Corporation (Kalamazoo, Mich.). The suction port 48 is configured to removably receive a suction tube to establish a suction path with a suction source, and the irrigation port 50 is configured to removably receive an irrigation tube to establish an irrigation path with a source of irrigation liquid. The suction source and / or the irrigation source may be integrated on the surgical console. The suction and irrigation paths of the surgical cutting instrument 40 may be at least similar to those disclosed in commonly-owned International Publication No. WO2021 / 224862, published November 11, 2021, and the aformentioned International Publication No. WO2022 / 123535, the entire contents of each being hereby incorporated by reference.

[0051] The cutting accessory 44 includes a hub, also referred to as an outer hub 58. The outer hub 58 includes coupling features (not identified) complementary to those of the handpiece 42 to releasably secure the cutting accessory 44 to the handpiece 42. The coupling features may be a latch or other suitable interlocking geometries, for example, those disclosed in the aforementioned International Publication No. WO2021 / 224862. The handpiece 42 defines at least one opening or cavity 60, and the cutting accessory 44 may include a drive hub 62 configured to be directed to within the cavity 60. The drive hub 62 is rotatably disposed within the outer hub 58 and includes at least one spline or interfacing geometry configured to be operably coupled with the motor with the outer hub 58 coupled to the handpiece 42. A seal 64 may be coupled to or disposed within the outer hub 58 to create a fluid-tight connection between the outer hub 58 and the handpiece 42 for delivery of the irrigation fluid through the cavity 60 and into an annular space defined between the drive hub 62 and the outer hub 58.

[0052] With further reference to FIG. 2, a tube assembly 66 extends distally from the outer hub 58 and includes an outer tube 68, and an inner tube forming a drive shaft 70. The outer tube 68 is coupled to the outer hub 58, and the drive shaft 70 is rotatably and coaxially disposed within the outer tube 68. The drive hub 62 is coupled to a proximal end of the drive shaft 70. A cutting tip 72 is at a distal end of the drive shaft 70. The illustrated implementation of the cutting accessory 44 is a bur in which a bur head 74 is coupled to the drive shaft 70. The drive shaft 70 is hereinafter referred to as a drive tube 70 in which the a suction lumen 82 is defined therethrough, but it is understood that the drive shaft 70 may be solid in section. A suction aperture 76 is disposed on the cutting tip 72 and position proximal to the bur head 74. The suction aperture 76 is in fluid communication with the suction lumen 82. The bur head 74 may be a diamond bur, fluted bur, orany other suitable type and size of bur head. It is also contemplated that aspects of the present disclosure may be used with other rotatable cutting implements such as a microdebrider, screwdriver, or the like. Further, the implementations of the cutting accessory 44, 44’ disclosed herein are depicted to include a tube assembly 66 that is straight; however, it is emphasized that the tube assembly 66 may optionally include at least one bend that is fixed or selectively adjustable.

[0053] The drive tube 70 includes at least one flexible region 71. As mentioned, the flexible region 71 is particularly well suited for implementations in which the tube assembly 66 is angled, malleable, or otherwise articulatable. The flexible region 71 of the drive tube 70 is configured to conform to a shape of the tube assembly 66 defined by the outer tube 68 and transmit torque therethrough. The flexible region 71 of the illustrated implementation includes castellated segments 78 interlocked with one another to define slots 79 therebetween, as shown in FIG. 2. The slots 79 may generally extend around the drive tube 70 in a spiral cut pattern. In certain implementations, the drive tube 70 may also include at least one wound or braided layer. A liner or jacket (not shown) may be coupled to and disposed over or within the flexible region 71 of the drive tube 70 to prevent egress of the irrigation fluid through the slots. The liner may be a heatshrink tubing disposed over an outer surface of the drive tube 70, or a tubular jacket coupled to the outer surface or an inner surface of the drive tube 70.

[0054] As shown throughout several figures starting with FIGS. 3 and 6, the cutting tip 72 includes a shank 88 coupled to a distal end 90 of the drive tube 70. The shank 88 includes a body 92, a neck 94 extending from the body 92, and the head 96 extending from the neck 94. The neck 94 may taper inwardly from the body 92 to the head 96. The suction aperture 76 may be disposed on the neck 94. An outer surface of the body 92 may define a recess, in particular an annular recess 98. A boss or circumferential flange 100 may separate the recess 98 from a proximal portion 102 of the body 92 to which the drive tube 70 is secured. As used herein, inwardly and outwardly refer to towards and away from a longitudinal axis of the tube assembly, respectively; axial refers to along the longitudinal axis; radial refers to about the longitudinal axis; distal refers to a direction towards the cutting tip; and proximal refers to a direction towards the outer hub 58.

[0055] To prevent axial movement or deflection of the cutting tip 72 relative to the outer tube 68 with rotation of the cutting tip 72, the cutting accessory 44 includes a retention member 80. In certain implementations, the retention member 80 is secured to the outer tube 68. Alternatively, the retention member 80 may be a feature of the outer tube 68. The retentionmember 80 is shaped and positioned to permit high-speed rotation of the cutting tip 72 while limited or preventing axial movement or deflection or movement of the cutting tip 72 relative to the outer tube 68. In other words, an amount by which the cutting tip 72 is positioned distal to a distal end 106 of the outer tube 68 remains fixed. The retention member 80 and the shank 88 of the cutting tip 72 may be arranged to form a journal bearing. The retention member 80 and / or the cutting tip 72 may include material properties configured to limit wear and heat generation. Such material properties include surface roughness, hardness, and the like. A lubricant may also be provided.

[0056] FIGS. 3-6 illustrate a first implementation of the retention member 80. The outer tube 68 defines a slot 104, and the retention member 80 is disposed within the slot 104 and secured to the outer tube 68. The retention member 80 may be welded, soldered, or affixed to the outer tube through other suitable joining means, and / or the retention member 80 may be an insert that is press fit into the slot 104. A sheath (not shown) may overly at least a portion of the outer tube 68, including the slot 104 and the retention member 80 disposed therein, such that the sheath secures the retention member 80 within the slot 104.

[0057] The slot 104 is spaced apart from the distal end 106 of the outer tube 68 and subtends a circumferential arc. In other words, the slot 104 may be a radial slot. The arc may be within the range of approximately 90 to 270 degrees, and more particularly within the range of approximately 145 to 235 degrees, and even more particularly approximately 180 degrees. The annular recess 98 of the shank 88 is axially aligned with the slot 104 of the outer tube 68. With the retention member 80 secured within the slot 104, at least a portion of retention member 80 is disposed within at least portion of the annular recess 98, as best shown in FIG. 6.

[0058] The retention member 80 is arcuate and may include an outer surface 108 that is contoured to an outer surface of the outer tube 68, and an inner surface 110 opposite the outer surface 108. The outer and inner surfaces 108, 110 may define thickness approximating a thickness of the outer tube 68. The retention member 80 is sized to subtend an arc equal to a size of the slot 104 within which it is secured. Therefore, for example, the retention member 80 may subtend an arc within the range of approximately 145 to 235 degrees, and more particularly approximately 180 degrees. One or more ribs 112 may extend from the inner surface 110. The ribs 112 extend inwardly from the inner surface 110 by a distance greater than the gap between the shank 88 and the outer tube 68. As a result, the ribs 112 are positioned within the annularrecess 98 of the shank 88. The ribs 112 are configured to provide bearing surfaces 114 with rotation of the cutting tip 72. The ribs 112 may be circumferentially spaced apart from one another. Among other advantages, the circumferential spacing limits friction between the retention member 80 and the shank 88 as well as defines voids therebetween for irrigating fluid to flow pass the retention member 80. The illustrated implementation includes three ribs 112, but more or less may be provided.

[0059] With the retention member 80 disposed within the annular recess 98, the retention member 80 is configured to prevent axial movement or deflection of the cutting tip 72 relative to the outer tube 68. With continued reference to FIG. 6, the bearing surface 114 of the rib 112 is positioned inwardly relative to an in close approximation with the outer surface of the shank 88. Such tolerancing between the bearing surface 114 and the outer surface of the shank 88 provides stability to the cutting accessory 44 during operation. Should distal forces urge the cutting tip 72 distally - either through, for example, the high-speed rotation or the back cutting technique - an annular distally-facing surface 116 that defines the annular recess 98 will contact the rib 112, after which further distal movement of the cutting tip 72 is prevented.

[0060] FIGS. 7-10 illustrate a second implementation of the retention member 80. The slot 104 of the outer tube 68 is an axial slot extending proximally from the distal end 106 of the outer tube 68, and the retention member 80 is disposed within the slot 104 and secured to the outer tube 68. More particularly, the retention member 80 includes a mounting head 118, and an engagement portion 120 extending from the mounting head 118. The mounting head 118 and the engagement portion 120 may be integrally formed. The mounting head 118 is sized complementary to the slot 104 of the outer tube 68, and the mounting head 118 may be contoured to the outer surface of the outer tube 68. In certain variants, the outer tube 68 may include a distal chamfer 122. The distal chamfer 122 is sloped complementary to the tapering of the neck 94 of the cutting tip 72 so as to improve visualization of the bur head 74 and the surgical site. The mounting head 118 of the retention member 80 may also include a chamfer 124 that is contoured to the chamfer 122 of the outer tube 68.

[0061] The mounting head 118 oriented axially within the axial slot, the engagement portion 120 is orthogonal to the mounting head 118. The engagement portion 120 is arcuate and disposed within the annular recess 98 of the shank 88. The outer surface 108 is contoured to an inner surface of the outer tube 68, and the inner surface 110 opposite the outer surface 108 definesa substantially constant thickness. Unlike the previous implementation in which the ribs 112 were primarily the structure occupying the annular recess 98, nearly an entirety of the engagement portion 120 is disposed within the annular recess 98 of the shank 88, as best shown in FIG. 9. The engagement portion 120 may subtend an arc within the range of approximately 145 to 235 degrees, and more particularly approximately 180 degrees.

[0062] One or more channels 123 may be defined by the engagement portion 120. The channels 123 may oriented longitudinally, i.e., between opposing sides defining a width of the retention member 80. In some respects the channels 123 may function similar to the voids between the ribs 112 of the implementation previously described, in other words to facilitate irrigating fluid flowing pass the retention member 80. There may be more or less than three channels 123, and the channel(s) may be wider, deeper, or of another suitable geometry. With the engagement portion 120 disposed within the annular recess 98, the retention member 80 is configured to limit or prevent axial movement or deflection of the cutting tip 72 relative to the outer tube 68 with rotation of the cutting tip 72. Should distal forces urge the cutting tip 72 distally, the annular distally-facing surface 116 contacts the engagement portion 120, after which further distal movement of the cutting tip 72 is prevented.

[0063] FIGS. 11-14 illustrate a third implementation of the retention member 80. In many respects the retention member 80 of the third implementation has characteristics of each of the first two implementations. The slot 104 is spaced proximally from the distal end 106 of the outer tube 68. The slot 104 is axially longer and generally square-shaped when viewed in plan. As appreciated from the annotated boundary, the retention member 80 may be considered to include the mounting head 118 and the engagement portion 120. The mounting head 118 sized to the slot 104, and the outer surface 108 is contoured to the outer surface of the outer tube 68. A thickness of the mounting head 118 defined between the outer surface 108 and the inner surface 110 may approximate a thickness of the outer tube 68. The engagement portion 120 extends inwardly from the mounting head 118 and is disposed within the annular recess 98 of the shank 88. The engagement portion 120 subtends less of an arc than the mounting head 118, for example, an arc within the range of approximately 15 to 135 degrees, and more particularly approximately within the range of 45 to 105 degrees. The retention member 80 may be devoid of ribs or channels, as shown, but such features may be incorporated on variants of the present implementation. Among other advantages, the retention member 80 of the present implementation may provide forease of manufacturability and associate expense while still achieving the engagement portion 120 being disposed within the annular recess 98 to limit or prevent axial movement or deflection of the cutting tip 72 relative to the outer tube 68 with rotation of the cutting tip 72. For example, the retention member 80 may be formed from polyether ether ketone (PEEK) and press fit into the slot 104. A sheath (not shown) may overly at least a portion of the outer tube 68, including the slot 104 and the retention member 80 disposed therein, such that the sheath further secures the retention member 80 within the slot 104. Therefore, certain methods of assembly of the cutting accessory 44 may include press fitting the retention member 80 into the slot 104, and securing the sheath to the outer tube 68 to overlie at least a portion of the outer tube 68 including the retention member 80.

[0064] FIGS. 15-18 illustrate a fourth implementation of the retention member 80, which does not require the slot extending through the outer tube 68 to which the retention member 80 is secured. Rather, an inner surface of the outer tube 68 defines an inner annular recess 126, and the annular recess 98 of the shank 88 is axially aligned with the inner annular recess 126 of the outer tube 68, as best shown in FIG. 18. The retention member 80 may include at least one arcuate member 128 disposed within the annular recesses 98, 126 and coupled to one of the outer tube 68 and the shank 88 of the cutting tip 72. A thickness of the arcuate member 128 is such that the annular distally-facing surface 116 engages the arcuate member 128 with distal movement of the cutting tip 72.

[0065] The illustrated implementation shows the arcuate member 128 as a clip, and in particular four clips. While there may be more or less than four clips, a collective length of the clip(s) should approximate a length of the annular recess 98 of the shank 88. For example, there may be a singular clip with a length approximating the length of the annular recess 98. Multiple, smaller clips may advantageously facilitate assembly of the cutting accessory 44 by being more easily deflectable to be inserted through the distal end 106 of the outer tube 68. A method of assembly may include resiliently expanding the clip(s) to be directed over and onto the shank 88, and in particular within the annular recess 98. The cutting tip 72 - prior to or after being coupled to the drive tube 70 - is directed through the distal end 106 of the outer tube 68 with the clip(s) in a resiliently compressed or narrowed state. In other words, an outer diameter of the clip(s) in an uncompressed state is greater than the diameter of the opening at the distal end 106 of the outer tube 68, and therefore it is necessary to compress the clip(s) for insertion therethrough. A toolmay be used to compress the clips. Once inserted and aligned with the inner annular recess 126 of the outer tube 68, the compression is removed, and the clip(s) resiliently return to the uncompressed state. The thickness of the clip(s) is sufficient for the retention member 80 to be disposed within the annular recess 98 of the shank 88, thereby limiting or preventing axial movement or deflection of the cutting tip 72 relative to the outer tube 68.

[0066] A fifth implementation is shown in FIGS. 19-22 in which the retention member 80 includes two shells or clamshells 130. Each of the clamshells 130 may include complementary keys 132 and key ways 134 configured to interlock with one another. The clamshells 130, among other advantages, may also obviate the need for the slot extending through the outer tube 68, and may further obviate the need for the inner annular recess within the outer tube 68. Rather, the clamshells 130, once assembled, include an outer diameter approximating the inner diameter of the outer tube 68 such that the retention member 80 is press fit. Another method of assembly includes positioning the clamshells 130 within the annular recess 98 on opposing sides of the cutting tip 72 such that the keys 132 and the keyways 134 interlock. The cutting tip 72 and the clamshells 130 - prior to or after being coupled to the drive tube 70 - are directed through the distal end 106 of the outer tube 68. The tolerancing results in a frictional fit of the clamshells 130 within the outer tube 68.

[0067] A sixth implementation of the retention member 80 is shown in FIGS. 23 and 24. The retention member 80 may be provided by at least one member or pin 136 extending through bores 138 defined by the outer tube 68. The pin(s) 136, once assembled, may have an outer surface that is contoured to or substantially flush with the outer surface of the outer tube 68. A length of the pin(s) 136, once assembled, may extend to within the annular recess 98 of the shank 88 of the cutting tip 72. Therefore, according to another method of assembly of the cutting accessory 44, the outer tube 68 may be secured to the outer hub 58. The shank 88 of the cutting tip 72 may be secured to the drive tube 70. The drive tube 70 may be coaxially directed into the outer tube 68 such that the annular recess 98 on the cutting tip 72 axially aligned with bores 138 extending through the outer tube 68. Thereafter, one of the pins 136 is directed through each of the bores 138 for a distal end of the pins to be positioned within the annular recess 98 of the shank 88 of the cutting tip 72. The pins 136 are secured to the outer tube 68 such that axial movement or deflection of the cutting tip 72 relative to the outer tube is prevented or limited. An excessportion 136’ of the pins 136 extending beyond a contour of the outer tube is severed, for example, through a machining operation.

[0068] Another implementation of the retention member 80 is shown in FIGS. 25-27. In many respects the present implementation is similar to the second implementation previously discussed. In particular, the slot 104 of the outer tube 68 is an axial slot extending proximally from the distal end 106 of the outer tube 68, and the retention member 80 is disposed within the slot 104 and secured to the outer tube 68. The retention member 80 includes the mounting head 118, and the engagement portion 120 extending from the mounting head 118. The outer tube 68 includes the distal chamfer 122, and the mounting head 118 includes the chamfer 124 contoured to the chamfer 122. The engagement portion 120 is arcuate and disposed within the annular recess 98 of the shank 88. The outer surface 108 is contoured to the inner surface of the outer tube 68, and the inner surface 110 opposite the outer surface 108 defines a substantially constant thickness. The retention member 80 includes at least one tab 140 extending outwardly from opposing sides of the mounting head 118. The tabs 140 are configured to be secured within complementary geometries forming part of the slot 104, as best shown in FIG. 26. The engagement provides additional axial support of the retention member 80 relative to the outer tube 68 against the distal forces that may act on the retention member 80 from the cutting tip 72.

[0069] An eighth implementation of the retention member 80 is shown in FIGS. 28 and 29. The retention member 80 may utilize interference fit to be secured to the outer tube 26, which may be an alternative or in addition to friction fit, welding, and other suitable joining means. The retention member 80 includes opposing wings 142, and a mounting head 144 disposed between the wings 142. Each of the wings 142 is arcuate and contoured to the inner surface of the outer tube 68. Likewise, an outer diameter of the retention member 80, defined between diametrically opposed points on the wings 142, may approximate the inner diameter of the outer tube 68 such that the wings 142 are configured to be press fit. The mounting head 144 is angled upwardly in a distal direction.

[0070] Each of the wings 142 and the mounting head 144 are separated by slots 146 extending inwardly from a distal side of the retention member 80. The illustrated implementation depicts the slots 146 extending for nearly of an entirety of the length of the retention member 80 defined between the distal side and an opposing proximal side. The depth of the slots 146 may realize at least two advantages. A material zone 147 between the slot 146 and the proximal sidemay be sufficiently small such that the wings 142 are configured to flex outwardly to facilitate coupling to the shank 88 of the cutting tip 72, and flex inwardly to facilitate assembly the press fit arrangement within the outer tube 68. Further, the mounting head 144 is effectively cantilevered to permit downward or inward flexion of the mounting head 144 during assembly. A method of assembly may include expanding the wings 142 to position the wings 142 within the annular recess 98 of the shank 88. Thereafter, the shank 88, with the retention member 80 coupled thereto, is directed through the distal end 106 of the outer tube 68. The wings 142 may deflect inwardly to do so, and the mounting head 144 may flex inwardly as an upper or outer surface of the mounting head 144 contacts the outer tube 68. Upon the mounting head 144 reaching or passing the slot 104 defined by the outer tube 68, the mounting head 144 resiliently flexes outwardly to within the slot 104, as best shown in FIG. 29. A distal surface 148 of the mounting head 144 engages a proximally-facing surface of the slot 104 via interference fit, thereby axially supporting of the retention member 80 relative to the outer tube 68 against the distal forces that may act on the retention member 80 from the cutting tip 72.

[0071] A ninth implementation of the retention member 80 is shown in FIG. 30. The retention member 80 may be formed by a retention feature integrally formed with the outer tube 68 as opposed to a separate component coupled thereto. FIG. 30 shows the outer tube 68 defining the slot 104 in a generally U-shaped configuration, which results in a tab 150 integral with the outer tube 68 on one side. Another tab (not shown) may be disposed on the opposing side of the outer tube 68. The tabs 150 may be positioned diametrically opposite one another, or at any suitable radial offset about the axis of the outer tube 68. It is further contemplated that more than two tabs may be provided. The tab(s) 150 are axially aligned with the annular recess 98 of the shank 88 of the cutting tip 72. During assembly of the cutting accessory 44, after the cutting tip 72 is appropriately positioned within the outer tube 68, the tab(s) 150 may be deflected inwardly to be disposed within the annular recess 98 of the shank 88, for example, through a crimping-like operation in which a base 151 of the tab(s) 150 undergo permanent deformation. Some material resiliency may cause the tab(s) 150 to deflect outwardly slightly after removal of the crimping force, which is preferable to prevent continuous contact between the tab(s) 150 and an outer surface of the shank 88.

[0072] The slot 104 may be dimensioned sufficiently small so as to minimize egress of irrigation fluid therethrough. In certain implementations, a width of the slot 104 may be between0.005 and 0.01 inches and formed through a suitable operation such as laser cutting, electronic discharge manufacturing (EDM), or the like. A distal portion of the slot 104a may be oriented circumferentially and spaced from the distal end of the outer tube 68 by a distance of between 0.05 and 0.07 inches. Likewise, a proximal portion of the slot 104c may be oriented circumferentially and spaced from the distal end of the outer tube 68 by a distance of between 0.12 and 0.16 inches. A middle portion of the slot 106b may be oriented longitudinally between the distal and proximal portions 104a, 104c. Corners of the intersections between the portions 104a, 104b, 104c may be rounded to minimize concentration of stresses.

[0073] The outer tube 68 may be formed from metal softer than that of the cutting tip 72. For example, the outer tube 68 may be formed from 304 stainless steel, whereas the cutting tip 72 is formed from 440A stainless steel. To prevent formation of particulates from the softer metal, the outer tube 68 may undergo a case hardening process. Additionally or alternatively, a lubricant may be disposed between the outer tube 68 and at least the cutting tip 72. One suitable lubricant is grease sold under the tradename such as a Molykote by DuPont (Wilmington, Dela.). It is further contemplated that a sheath (not shown) may be disposed over at least a portion of the outer tube 68 including the slot(s) 104.

[0074] The tenth implementation of the retention feature 80 of FIG. 31 utilizes the tapering of the neck 94 of the cutting tip 72. The present implementation may also obviate the need for the annular recess 98 on the shank 88. The retention feature 80 is a crown including tabs 152 arranged circumferentially about the distal end 106 of the outer tube 68. During assembly of the cutting accessory 44, after the cutting tip 72 is appropriately positioned within the outer tube 68, the tabs 152 may be deflected inwardly to an angle approximating the taper of the neck 94 of the cutting tip 72. Should distal forces urge the cutting tip 72 distally, inner surfaces of the tabs 152 constrain the axial movement or deflection of the neck 94, and therefore of the cutting tip 72.

[0075] The implementations of the retention member 80 have been depicted and described for use with a bur-type cutting accessory. It should be understood, however, that the retention member 80 may be incorporated on any cutting accessory in which it is desired to maintain axial position of a rotatable drive tube relative to an outer tube. For example, the implementations of the retention member 80 may be well suited for use with a microdebrider cutting accessory. While the drive and outer tubes of the microdebrider cutting accessory have closed distal ends that provides a stop to distal movement of the drive tube, it may be desirable tolimit wear at these closed distal ends. Such variants may require modification of the drive tube 70 to provide the annular recess 98 within which the retention member 80 is disposed, as the microdebrider cutting accessory may not include a cutting tip with a shank.

[0076] Another benefit of the retention member 80 includes providing a microdebrider cutting accessory with an adjustable working length. Referring now to FIGS. 32-35, the tube assembly 66 of the microdebrider cutting accessory 44’ includes the cutting tip 72 in which the drive tube 70 defines a cutting edge that is rotated within a cutting window 73 of the outer tube 68 to shear or debulk the tissue. Therefore, providing an adjustable working length to the tube assembly 66 of the microdebrider cutting accessory requires complementary translation of the drive tube 70 with adjustment of the outer tube 68. The microdebrider cutting accessory 44’ includes the outer hub 58, and the tube assembly 66 extending distally from the outer hub 58. The tube assembly 66 includes an outer tube 68, and the drive tube 70 rotatably and coaxially disposed within the outer tube 68. The cutting tip 72 is coupled to or formed in part by the drive tube 70, and includes the cutting window 73 in fluid communication with the suction lumen 82 defined by the drive tube 70. The retention member 80 is coupled to the outer tube 68, as shown in FIG. 32, and may be any of the implementations of the retention member 80 disclosed herein.

[0077] Referring to FIGS. 34 and 35, the drive tube 70 includes driven features 160 on a proximal portion of the drive tube 70. The proximal portion of the drive tube 70 may include the proximal end, and a predetermined length distally therefrom that is at least equal to an adjustable length of the microdebrider cutting accessory 44’. The microdebrider cutting accessory 44’ includes a telescoping drive coupler 162 engaging the driven features 160 and configured to permit for adjustment of the working length of the tube assembly 66 (z.e., a length by which it extends beyond the outer hub 58) while being capable of transmitting torque from the motor of the handpiece 42 regardless of the working length. The telescoping drive coupler 162 includes the drive hub 62 coupled to the drive tube 70 and including at least one spline or interfacing geometry configured to be operably coupled with a complementary geometry of the motor with the outer hub 58 coupled to the handpiece 42. The seal 64, hereinafter the proximal seal, may be coupled to or disposed within the outer hub 58 to create a fluid-tight connection for delivery of the irrigation fluid through the outer hub 58.

[0078] The telescoping drive coupler 162 further includes a cannulated rotor 164. The cannulated rotor 164 is coupled to the drive hub 62 and includes drive features 166 configured toengage the driven features 160 of the drive tube 70. The illustrated implementation shows the drive and driven features 160, 166 being complementary splines 168 extending longitudinally within the cutting accessory 44’. The splines 168 are secured to a distal hub 172 of the cannulated rotor 164 and radially offset from one another so as to mesh regardless of the working length of the tube assembly 66 that is selected by a user. In other words, engagement between the drive features 166 of the cannulated rotor 164 and the driven features 160 of the drive tube 70 is configured to transfer torque between the two yet provide for translation of the drive tube 70 relative to the cannulated rotor 164. The splines 168 of the drive feature 166 may be disposed on an inner diameter of the cannulated rotor 164, and the splines 168 of the driven features 160 may be disposed on an outer diameter of the drive tube 70. A proximal cap 174 may be disposed within the drive hub 62 and configured to support proximal ends of the splines 168 of the drive features 166. A seal 176, such as O-ring may be coupled to the proximal cap 174 and engaging an inner diameter of the canulated rotor 164.

[0079] FIG. 34 shows the outer hub 58 defining an internal cavity 178. A stop feature 180 may be coupled to the outer tube 68, for example, at or near its proximal end, and is movable with adjustment of the working length of the tube assembly 66. The stop features 180 moves within the internal cavity 178 and contacts the outer hub 58 in a fully “retracted” position (z.e., shortest working length) and fully “extended” position (z.e., longest working length). The outer hub 58 may define a seal cavity 182 through which the tube assembly 66 extends. A dynamic seal 184 may be disposed within the seal cavity 182. The cutting accessory 44’ is configured to have irrigating fluid enter the outer hub 58 between the seal 64 and the cannulated rotor 164, after which the irrigating fluid is directed between the outer tube 68 and the drive tube 70. Owing to the adjustability of the working length, the irrigation fluid may also enter the internal cavity 178, and therefore the dynamic seal 184 is configured to prevent the irrigating fluid from egress between the outer hub 58 and the outer tube 68. The seal is “dynamic” in that is provides for movement of the outer tube 68 against which it is configured to seal, but thereafter prevents egress of irrigating fluid therebetween.

[0080] The cutting accessory 44’ includes a locking mechanism 186 coupled to the outer hub 58. The locking mechanism 186 is configured to permit the cutting accessory 44’ to be actuated or moved between a locked state and an unlocked state in which the working length of the tube assembly 66 is not adjustable and adjustable, respectively. In particular, in the unlockedstate, the outer tube 68 is translatable relative to the telescoping drive coupler 162. FIG. 33A shows the locking mechanism 186 in the locked state, and FIG. 33B shows the locking mechanism 186 in the unlocked state. The illustrated implementation shows the locking mechanism 186 as a dial 188 defining a cavity 190 including internal threads 192 disposed therein. The internal treads of the dial 188 is configured to engage external threads 194 of the outer hub 58. The dial 188 also includes compression tabs 196 disposed within the cavity 190 and configured to be deflected by projections of the outer hub 58 to engage the outer tube 68 by friction force in the locked state.

[0081] In operation, the user provides an input to the dial 188 to move the locking mechanism 186 from the locked state to the unlocked state. The user may then provide another input (e.g., with the opposing hand) to translate the outer tube 68 distally or proximally relative to the outer hub 58. Such translation of the outer tube 68, in and of itself, does not impart complementary translation of the drive tube 70. As mentioned, however, the retention member 80 advantageously couples the drive tube 70 to the outer tube 68, and in particular, axially fixes the position of the drive tube 70 to the outer tube 68 while permitting rotation therebetween. As a result, the retention member 80, upon the input to translate the outer tube 68 distally or proximally, causes complementary translation of the drive tube 70. In effect, the user adjusts the working length of the tube assembly 66 with the locking mechanism 186 in the unlocked state, after which the user actuates the locking mechanism 186 to the locked state to fix the working length at the desired length. In one non-limiting example, the working length is configured to be extended and retracted by a distance within the range of two to seven centimeters, however, more adjustability is contemplated. Owing to the telescoping drive coupler 162 in combination with the retention member 80, the surgeon is able to adjust the working length quickly and efficiently with little downtime in the surgical procedure.

[0082] In addition to or as an alternative to a manual input to the tube assembly 66 to adjust the working length, the cutting accessory 44’ may include an actuator (not shown) coupled to the outer hub 58 and operably coupled to the outer tube 68. The actuator is configured to receive a user input to cause translation of the outer tube 68 relative to the telescoping drive coupler 162. Examples of the actuator are a geared mechanism and a slider mechanism.

[0083] The foregoing disclosure is not intended to be exhaustive or limit the invention to any particular form. The terminology which has been used is intended to be in the nature of words of description rather than of limitation. Many modifications and variations are possible inlight of the above teachings and the invention may be practiced otherwise than as specifically described. Many of the implementations described herein may be combined with one another.

[0084] Certain inventive aspects of the present disclosure are included in the following exemplary clauses:

[0085] Clause 1 - A cutting accessory for a powered surgical instrument, the cutting accessory comprising: an outer hub configured to be removably coupled to a handpiece of the powered surgical instrument; an outer tube extending from the outer hub; a drive tube coaxially and rotatably disposed within the outer tube and comprising driven features on a proximal portion of the drive tube; a cutting tip coupled to the drive tube; a telescoping drive coupler comprising: a drive hub coupled to the drive tube and comprising geometries configured to engage complementary geometries of a motor of the powered surgical instrument; a cannulated rotor coupled to the drive hub and comprising drive features configured to transfer torque to the driven features on the proximal portion of the drive tube, wherein engagement between the drive features and the driven features is further configured to provide for translation of the drive tube relative to the cannulated rotor; and a retention member operably coupling the drive tube to the outer tube, wherein the retention member is configured to cause complementary translation of the drive tube with translation of the outer tube.

[0086] Clause 2 - The cutting accessory of clause 1 , wherein the drive feature and the driven feature are complementary splines.

[0087] Clause 3 - The cutting accessory of clause 2, wherein the splines of the drive feature are disposed on an inner diameter of the cannulated rotor, and wherein the splines of the driven feature are disposed on an outer diameter of the drive tube.

[0088] Clause 4 - The cutting accessory of clause 3, wherein the telescoping drive coupler further comprises: a cap coupled disposed within the cannulated rotor and coupled to a proximal end of the drive features; and a seal coupled to the cap and engaging the inner diameter of the cannulated rotor.

[0089] Clause 5 - The cutting accessory of any one of clauses 1 -4, further comprising a locking mechanism coupled to the outer hub and selectively engaging the outer tube, wherein the locking mechanism is configured to receive a user input to move the cutting accessory from a locked state to an unlocked state in which the outer tube is translatable relative to the telescoping drive coupler.

[0090] Clause 6 - The cutting accessory of clause 5, wherein the locking mechanism is a dial defining a cavity and comprising an internal threads disposed within the cavity and configured to engage external threads of the outer hub, and compression tabs disposed within the cavity and configured to be deflected by projections of the outer hub to engage the outer tube by friction force in the locked state.

[0091] Clause 7 - The cutting accessory of any one of clauses 1 -6, further comprising an actuator coupled to the outer hub and operably coupled to the outer tube, wherein the actuator is configured to receive a user input to cause translation of the outer tube relative to the telescoping drive coupler; and, optionally, wherein the actuator is one of a geared mechanism and a slider mechanism.

[0092] Clause 8 - The cutting accessory of any one of clauses 1-7, wherein the outer tube is configured to be extended and retracted by a distance within the range of two to seven centimeters.

[0093] Clause 9 - The cutting accessory of any one of clauses 1-8, wherein the cutting accessory is a microdebrider in which the outer tube defines a cutting window and the drive tube is a drive tube disposed within the outer tube, wherein the drive tube defines a suction lumen.

[0094] Clause 10 - The cutting accessory of clause 9, wherein an irrigation lumen is defined between the outer tube and the drive hub, and wherein the cutting accessory further comprises a seal disposed within the outer hub and in sealing engagement with the proximal portion of the outer tube to prevent egress of irrigation fluid from the irrigation lumen; and, optionally, wherein the seal is a dynamic seal.

[0095] Clause 11 - A method of assembly of a cutting accessory for a powered surgical instrument, the method comprising: securing an outer tube to an outer hub; securing a shank of a cutting tip to a drive shaft; and crimping at least one tab formed on the outer tube with the drive shaft coaxially disposed within the outer tube, wherein the at least one tab is deflected inwardly permanently deforms within an annular recess defined by an inner surface of the outer tube, thereby limiting or preventing axial movement or deflection of the cutting tip relative to the outer tube.

[0096] Clause 12 - The method of clause 11, wherein the at least one tab is two tabs diametrically positioned opposite to one another.

[0097] Clause 13 - A method of assembly of a cutting accessory for a powered surgical instrument, the method comprising: securing an outer tube to an outer hub; securing a shank of acutting tip to a drive shaft; coaxially directing the drive shaft into the outer tube, wherein an annular recess on the shank of the cutting tip is axially aligned with a slot extending through the outer tube; thereafter, directing a retention member into the slot to be positioned within an annular recess of the shank of the cutting tip; and securing the retention member to the outer tube such that axial movement or deflection of the cutting tip relative to the outer tube is prevented.

[0098] Clause 14 - The method of clause 13, wherein the step of securing the retention member further comprises welding the retention member to the outer tube.

[0099] Clause 15 - The method of clause 13, wherein the step of securing the retention member further comprises: press fitting the retention member into the slot; and securing a sheath to the outer tube to overlie at least a portion of the outer tube including the retention member.

[0100] Clause 16 - A method of assembly of a cutting accessory for a powered surgical instrument, the method comprising: securing an outer tube to an outer hub; securing a shank of a cutting tip to a drive shaft; securing at least one clip within an annular recess of the shank of the cutting tip; and compressing the at least one clip while coaxially directing the drive shaft into the outer tube, wherein the at least one clip resiliently returns to an uncompressed state upon encountering an annular recess defined by an inner surface of the outer tube, thereby limiting or preventing axial movement or deflection of the cutting tip relative to the outer tube.

[0101] Clause 17 - A method of assembly of a cutting accessory for a powered surgical instrument, the method comprising: securing an outer tube to an outer hub; securing a shank of a cutting tip to a drive shaft; coaxially directing the drive shaft into the outer tube, wherein an annular recess on the shank of the cutting tip is axially aligned with bores extending through the outer tube; thereafter, directing a pin through each of the bores for a distal end of the pin to be positioned within an annular recess of the shank of the cutting tip; securing the pins to the outer tube such that axial movement or deflection of the cutting tip relative to the outer tube is limited or prevented; and severing an excess portion of the pins extending beyond a contour of the outer tube.

[0102] Clause 18 - A cutting accessory for a powered surgical instrument, the cutting accessory comprising: a hub configured to be removably coupled to a handpiece of the powered surgical instrument; an outer tube extending from the hub and defining a slot; a drive shaft coaxially and rotatably disposed within the outer tube; a cutting tip comprising a shank disposed at or coupled to a distal end of the drive shaft, wherein the shank defines an annular recess axially aligned with the slot of the outer tube; and a retention member disposed within the slot and securedto the outer tube, wherein the retention member is arcuate and disposed within at least a portion of the annular recess of the shank.

[0103] Clause 19 - The cutting accessory of clause 18, wherein the retention member is welded to the outer tube.

[0104] Clause 20 - The cutting accessory of clause 18, wherein the retention member is an insert is press fit into the slot, and wherein the cutting accessory further comprises a sheath overlying at least a portion of the outer tube including the retention member to secure the retention member within the slot.

[0105] Clause 21 - The cutting accessory of clause 18, wherein the retention member further comprises a mounting head secured to the outer tube, and an engagement portion extending from the mounting head, and wherein the mounting head is sized complementary to the slot of the outer tube.

[0106] Clause 22 - The cutting accessory of clause 21, wherein the slot is an axial slot extending proximally from a distal end of the outer tube, wherein the outer tube comprises a distal chamfer, and wherein the mounting head comprises a chamfer contoured to the distal chamfer.

[0107] Clause 23 - The cutting accessory of clause 22, wherein the cutting tip is a bur in which the shank comprises a neck tapering from the shank and terminating at a bur head, wherein the chamfers of the outer tube and the mounting head are sloped complementary to the tapering of the neck of the shank.

[0108] Clause 24 - The cutting accessory of clause 23, wherein the neck defines a suction port.

[0109] Clause 25 - The cutting accessory of clause 21, wherein an outer surface of the mounting head is contoured to an outer surface of the outer tube.

[0110] Clause 26 - The cutting accessory of clause 18, wherein the slot is a radial slot, and wherein an outer surface of the retention member is contoured to the outer surface of the outer tube.

[0111] Clause 27 - The cutting accessory of any one of clauses 18-26, wherein the retention member comprises ribs circumferentially spaced apart from one another, wherein the ribs are configured to provide bearing surfaces with voids therebetween configured to provide for irrigation flow through the retention member.

[0112] Clause 28 - The cutting accessory of any one of clauses 18-27, wherein the retention member subtends an arc of at least 145 degrees.

[0113] Clause 29 - The cutting accessory of clause 28, wherein the retention member subtends an arc of no greater than 235 degrees.

[0114] Clause 30 - The cutting accessory of clause 29, wherein the retention member subtends an arc of approximately 180 degrees.

[0115] Clause 31 - The cutting accessory of clause 18, wherein the retention member are at least two clamshells each comprising keys and keyways and configured to interlock with one another; and, optionally, wherein the clamshells engage an inner surface of the outer tube via friction fit.

[0116] Clause 32 - The cutting accessory of clause 18, wherein the retention member comprises: a mounting head angled upwardly in the distal direction; and opposing wings that are arcuate and separated from the mounting head by slots, wherein the mounting head is configured to be deflected to the slot of the outer tube.

[0117] Clause 33 - A cutting accessory for a powered surgical instrument, the cutting accessory comprising: a hub configured to be removably coupled to a handpiece of the powered surgical instrument; an outer tube extending from the hub and comprising an inner surface defining an annular recess; a drive shaft coaxially and rotatably disposed within the outer tube; a cutting tip comprising a shank coupled to a distal end of the drive shaft, wherein the shank comprises defines an annular recess axially aligned with the annular recess of the outer tube; and a retention member disposed within the annular recesses and coupled to one of the outer tube and the shank of the cutting tip, wherein the retention member is configured to prevent axial movement or deflection of the cutting tip relative to the outer tube with rotation of the cutting tip.

[0118] Clause 34 - The cutting accessory of clause 33, wherein the retention member is at least one clip secured to the cutting tip and having an outer diameter greater than an outer diameter of the shank, and, optionally, wherein the least one clip is exactly four clips.

Claims

CLAIMS1. A cutting accessory for a powered surgical instrument, the cutting accessory comprising: a hub configured to be removably coupled to a handpiece of the powered surgical instrument; an outer tube extending from the hub; a drive shaft coaxially disposed within the outer tube; a cutting tip comprising a shank coupled to a distal end of the drive shaft, wherein the shank defines an annular recess; and means for resisting movement of the cutting tip relative to the outer tube against forces applied to the cutting tip, wherein the means are disposed within the annular recess of the shank of the cutting tip.

2. The cutting accessory of claim 1 , wherein the means comprise a retention feature integrally formed with the outer tube and deflected inwardly within the recess of the shank.

3. The cutting accessory of claim 2, wherein the retention feature comprises a tab formed from a slot within the outer tube, and, optionally, wherein the slot is U-shaped.

4. The cutting accessory of claim 3, wherein proximal and distal portions of the slot are oriented circumferentially, and wherein a middle portion of the slot extends longitudinally between the proximal and distal portions.

5. The cutting accessory of claim 2 or 3, wherein the retention feature further comprises another tab formed from another slot, and, optionally, wherein the tabs are diametrically opposite one another.

6. The cutting accessory of claim 1, wherein the means comprise a distal end of the outer tube forming a retention feature deflected inwardly and contoured to a neck of the cutting tip.

7. The cutting accessory of claim 1, wherein the outer tube defines a slot, and wherein the means comprises an arcuate retention member disposed within the slot and secured to the outer tube, and, optionally, wherein the retention member is welded to the outer tube.

8. The cutting accessory of claim 1, wherein the outer tube defines a slot, and wherein the means comprise a retention member that is an insert is press fit into the slot, and wherein the cutting accessory further comprises a sheath overlying at least a portion of the outer tube including the retention member to secure the retention member within the slot.

9. The cutting accessory of claim 1, wherein the means comprise a retention member comprising at least two clamshells each comprising keys and keyways and configured to interlock with one another; and, optionally, wherein the clamshells engage an inner surface of the outer tube via friction fit.

10. The cutting accessory of claim 1, wherein the outer tube defines a slot, and wherein the means comprise a retention member comprising: a mounting head angled upwardly in the distal direction; and opposing wings that are arcuate and separated from the mounting head by slots, wherein the mounting head is configured to be deflected to the slot of the outer tube.

11. The cutting accessory of claim 1 , wherein the outer tube defines a slot, and wherein the means comprises a retention member including a mounting head secured to the outer tube, and an engagement portion extending from the mounting head, and wherein the mounting head is sized complementary to the slot of the outer tube.

12. The cutting accessory of claim 11, wherein the slot is an axial slot extending proximally from a distal end of the outer tube, wherein the outer tube comprises a distal chamfer, and wherein the mounting head comprises a chamfer contoured to the distal chamfer.

13. The cutting accessory of claim 12, wherein the cutting tip is a bur in which the shank comprises a neck tapering from the shank and terminating at a bur head, wherein thechamfers of the outer tube and the mounting head are sloped complementary to the tapering of the neck of the shank.

14. The cutting accessory of claim 1, wherein the means comprises a retention member comprising ribs circumferentially spaced apart from one another, wherein the ribs are configured to provide bearing surfaces with voids therebetween configured to provide for irrigation flow through the retention member.

15. The cutting accessory of claim 14, wherein the means comprises a retention member comprising at least one clip secured to the cutting tip and having an outer diameter greater than an outer diameter of the shank, and, optionally, wherein the least one clip is exactly four clips.

16. The cutting accessory of any one of claims 1-15, wherein the drive shaft is a drive tube defining a lumen and comprising geometries configured to provide flexibility to the drive tube with rotation by a motor of the powered surgical instrument, and wherein the retention member is configured to prevent axial deflection of the cutting tip relative to the outer tube with rotation of the cutting tip.

17. The cutting accessory of any one of claims 1-16, further comprising: a drive hub coupled to the drive tube and comprising geometries configured to engage complementary geometries of a motor of the powered surgical instrument; and a telescoping drive coupler operably coupling the outer tube and the drive hub, wherein the telescoping drive coupler is configured to transfer torque from the drive hub to the drive tube while providing for translation of the outer tube relative to the hub, wherein the retention member is configured to cause complementary translation of the drive tube with translation of the outer tube.

18. The cutting accessory of claim 17, further comprising complementary splines on the telescoping drive coupler and the drive tube.

19. The cutting accessory of claim 17 or 18, further comprising a locking mechanism coupled to the hub and selectively engaging the outer tube, wherein the locking mechanism is configured to receive a user input to move the cutting accessory from a locked state to an unlocked state in which the outer tube is translatable relative to the telescoping drive coupler.

20. The cutting accessory of any one of claims 17-19, wherein the outer tube is configured to be extended and retracted by a distance within the range of two to seven centimeters.

21. The cutting accessory of any one of claims 17-20, wherein the cutting accessory is a microdebrider in which the outer tube defines a cutting window and the drive tube defines a suction lumen.

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