Abstract: Disclosed herein are gear shifters to reverse an output shaft rotation and a method for using the same. A gear shifter in accordance with the present invention may include a housing, an input shaft, an output shaft and an idler shaft. The input shaft may have input gears, the output shaft may have output gears and the idler shaft may have idler gears. The output shaft may be slidably coupled with the input shaft and the idler shaft to rotate in a first direction in a first position and in a second opposite direction in a second position. A method of reversing an output shaft direction using a gear shifter may include the steps of pushing the gear shifter in a first direction to rotate the output shaft in a first direction and pushing the gear shifter in a second direction to rotate the output shaft in a second direction.

Abstract: A surgical instrument is provided. The surgical instrument has a drill bit employable in drilling procedures wherein the drill bit has an internal grasping hook. As a result, the drill bit may not only drill into bone, but may also be used to grasp an object within or part of the body. The present surgical instrument reduces contamination and difficulty which may otherwise result from switching surgical instruments from a drill to a grasping mechanism or from the need to drill multiple holes into the patient's body.

Abstract: A method of inserting a screw into a fusion cage, comprising the step of: i) attaching a screw head of a bone screw to a flexible bone screw driver comprising: a) a proximal handle, b) an intermediate shaft, c) a flexible distal end portion comprising a plurality of interlocking segments portion defining a periphery and a distal tip adapted to engage the screw head, and d) a flexible pre-bent sleeve that is configured to be placed radially over and around the plurality of interlocking segments to provide a loaded configuration, wherein the plurality of interlocking segments portion is substantially straight in its unloaded configuration, whereby the pre-bent sleeve pre-determines the trajectory of the tip in the loaded configuration, ii) inserting the bone screw into a threaded throughhole of a fusion cage comprising a front wall, a pair of opposing side walls, a back wall, and top and bottom surfaces adapted for gripping opposed vertebral endplates, wherein the front wall comprises the threaded thro

Abstract: An orthopedic burring tool includes a burring tip configured for removal of bone to form a bore in the bone, an elongated intermediate segment having a smooth outer surface along a length of the segment, a conical widening segment at the proximal end of the intermediate segment that widens from the diameter of the burring tip to a diameter that is about twice the burring tip diameter. The widening segment includes an outer surface configured for removal of bone upon rotation of the burring tool. The tool includes an upper segment configured for engagement to a rotary driving tool and having a cylindrical outer surface configured for removal of bone upon rotation of the burring tool for removal of material from bony structure adjacent the bone bore formed by the burring tip.

Abstract: An orthopaedic surgical instrument for use in disassembling an orthopaedic prosthesis includes a main component, a rod, and a spindle. The main component has a housing and an elongated body extending from the housing with a passageway is defined in the elongated body. The rod has an elongated shaft, with a greater length than the elongated body, extending from the head of the rod and configured to pass through the main component. The spindle threads into the housing to move the rod along a longitudinal axis.

Abstract: A catheter can restore the patency of a body lumen, for example, by removing tissue from a body lumen (e.g., a blood vessel). The catheter can be a rotational catheter having a rotatable drive shaft and a tissue-removing element secured to the drive shaft to be driven in rotation by the drive shaft. The catheter can have an abrasive burr configured to abrade tissue in a body lumen. The catheter can have an expandable tissue-removing element. The catheter can include a balloon and an inflation conduit. The catheter can also be configured to move over a guidewire through a body lumen. In one embodiment, the catheter comprises an over-the-wire, balloon-expandable, rotational, and abrasive tissue-removing catheter.

Abstract: A drill guide arm for providing guidance for placement of a bone tunnel, while protecting against trauma. The guide arm includes a first arm at a proximal end connected at an angle to a second arm, the second arm extending to a distal end. The angle can be within the range of 80°-110°. The second arm extends along a first axis. The guide arm also includes a distal tip extending at a second angle from the second arm at the distal end, and an indicator feature extending from the distal tip toward the first arm. The indicator feature extends along a second axis, the second axis being substantially parallel to the first axis. The guide arm can also include a shield feature of the distal tip. The shield feature has a width wider than the remainder of the distal tip.

Abstract: A method of assembling a surgical instrument is provided. The method comprises connecting a part with a first member, the first member extending between a proximal end and a distal end, the proximal end including at least one mating surface disposed a selected distance from the distal end for engagement with a navigation component, the part having an opening and the distal end being inserted through the opening and translated to a selected position with the first member. Systems, spinal constructs and implants are disclosed.

Abstract: An assembly may include a medical device, an introducer sheath connected to the medical device, and a surgical instrument. The medical device may include a cage, a screw, a bone screw, a pedicle screw, and/or an implant. The introducer sheath may be connected to the medical device at a pre-determined breaking point. The introducer sheath may be hollow. The surgical instrument may comprise an extension. The extension may be configured to be inserted into the introducer sheath. The surgical instrument may comprise a pin. The surgical instrument may comprise a separator. The separator may be configured for breaking off the introducer sheath from the medical device at the pre-determined breaking point by rotating the extension about a longitudinal axis of the extension. A part of the medical device may be configured serve as a counter bearing to the rotation by accommodating the pin during rotation.

Abstract: A bone plate kit may be provided for a foot or ankle orthopedic procedure, such as a lapidus procedure. In some examples, the bone plate kit includes a sterile container that holds multiple unicortical bone plate fasteners and one or more bone plates. For example, the kit may contain two bone plates configured to be used together during a tarsal-metatarsal fusion procedure. Each of the two bone plates may be configured to span different regions of a tarsal-metatarsal joint. The unicortical bone plate fasteners can be used to secure the two bone plates to the first metatarsal and medial cuneiform of a patient undergoing a procedure. In some configurations, one of the bone plates is a helical bone plate while the other bone plate may or may not be a helical bone plate.

Abstract: A medical assembly implanting a transcatheter heart valve in the heart at a valve deployment site and related methods of implantation and delivery. An anchor is endovascularly introduced into the heart and implanted to a cardiac wall with an anchor delivery system and delivery cable. A second delivery system introduces a tether which coupled to the implanted anchor and a transcatheter heart valve. The transcatheter heart valve includes either a top or bottom brim which is positioned to conform to the atrial floor at the deployment site.

Abstract: Embodiments of a compliant orthopedic driver are disclosed herein. In some embodiments, compliant orthopedic driver includes a body extending from a proximal end to a distal end along a driver axis; a driver tip disposed at the distal end of the body, wherein the body includes at least one compliant portion configured to allow the driver flex about at least two axes transverse to the driver axis.

Abstract: Devices and systems for track tension measurement and alignment of tracked vehicles are provided. A device for measuring tension on a continuous track includes a shaft having a hollow cross section, a pin disposed at least partially through an aperture of the top end of the shaft, a compression member disposed within the inner volume of the shaft such that the pin contacts the compression member, and a base having a hollow cross section and removably attached to an outer surface of the shaft. When the base is attached to the outer surface of the shaft at a predetermined height, and the pin is depressed into the inner volume of the shaft at a predetermined distance, the distance between the top end of the pin and an end of the base is known.

Abstract: An adjustable construct for fixation of a tendon or ligament graft in a tunnel. The construct comprises a flexible, adjustable loop connected to tissue (for example, graft, ligament or tendon). The adjustable loop may be integrated with an additional tissue supporting device (for example, a wedge or a plug). The tissue is secured within a bone socket/tunnel by adjusting the length of the flexible adjustable loop.

Abstract: Methods and devices are provided for anchoring a ligament or tendon to bone. In one embodiment, a surgical implant is provided having a sheath and an expander that is received within the sheath. Various delivery tools, including a sheath inserter and a driver, are also provided. In use, the sheath inserter can be used to position a tendon within a prepared bone hole, and it can be used to deliver the sheath with a guidewire coupled thereto into the bone hole. The driver can be provided for delivering the expander into the sheath. A loader can optionally be used to load the driver and expander onto the guidewire coupled to the implanted sheath.

Abstract: A surgical instrument having a first member engageable with a first end of a fastener having a second end configured to penetrate tissue. A second member includes an expandable member configured for engaging the first end. Systems and methods are disclosed.

Abstract: A method of assembling a surgical construct includes installing a fastener within a bone of a patient. A connector rod is positioned on the fastener and an interference or press fit is created between the fastener and the rod, with very little effort required on the surgeon's part. No additional steps are necessary or desirable; the surgeon can simply position the rod over the fastener, and very quickly and accurately couple the two one to another. A securing device can be used to couple the fastener and the rod, and a different device can be used to uncouple the fastener from the rod. The securing device engages the fastener and the rod, and pushes the rod over the fastener as the surgeon activates the gripping mechanism.

Abstract: Various articulating tools for endoscopic placement of fasteners are disclosed. The tool can comprise a multi-angle articulating screwdriver. The tool can have an elongate shaft with an articulating driver head at a distal end. The tool can rotate the articulating driver head to drive fasteners, such as screws, to a surgical site. The articulating driver head can articulate with respect to a longitudinal axis of the elongate shaft to enable the fastener to be driven at various angle. The tool can be coupled to a powered handpiece power and can transmit torque from the handpiece to the driver head.

Abstract: A torque transfer assembly for a bit holder includes a first lateral member, a second lateral member and a coupling pin. The first and second lateral members extend substantially parallel to each other along opposing sides of an axial channel of a base portion of a drive body of the bit holder. The drive body includes a drive end configured to interface with a powered driver. The coupling pin interfaces between the drive body and a driven body of the bit holder to transfer torque between the drive body and the driven body via engagement between the coupling pin and the first and second lateral members.

Abstract: An endosteal guide pin for preparing a guide path for the implantation of a pedicle or orthopaedic screw into a patient's bone. The pin has a head intended to be provisionally implanted in a bone and a guide rod, coaxial with and rigidly secured to the head, ending in a free end intended to be at least level with the skin surface of the patient when the pin is in the implanted position in the bone. The pin has a first coupling part intended at least to secure the pin to and release the pin from at least one portion of a positioning trocar and a second coupling part intended at least to secure the pin to a removal trocar. Also, a trocar for positioning a guide pin, which trocar incorporates the guide pin, and to a trocar for removing the pin.

Abstract: Systems, instruments, and methods for attaching a head assembly to a fastener are provided. The systems, instruments, and methods may include a surgical instrument. The surgical instrument may include an elongated first member; a first tubular member, in which a portion of the elongated first member is positioned within the first tubular member; a second tubular member, in which the portion of the elongated first member and a portion of the first tubular member are positioned within the second tubular member; and at least one grasping member, in which a portion of the at least one grasping member is pivotably coupled to the first tubular member and another portion of the at least one grasping member is pivotably coupled to the second tubular member. In one or more cases, the at least one grasping member may actuate translation of the first tubular member and the second tubular member.

Abstract: A bone positioning guide may include a main body member, a shaft, and a bone engagement member. The shaft can be movably connected to the main body member and have the bone engagement member rotatably coupled to its distal end. The bone engagement member can have a surface configured to engage a bone. The main body member can also include a tip opposite the bone engagement member for engaging a second bone. In use, the bone engagement member may be positioned in contact with a medial side of a first metatarsal while the tip is positioned in contact with a lateral side of a different metatarsal, such as a second metatarsal. The shaft can then be moved to advance the bone engagement member toward the tip, causing realignment of the first metatarsal.

Abstract: Methods of attaching a soft tissue to an adjacent bone at a defect site are provided. An adjustable loop region of a flexible construct contained in a bore defined by a fastener is passed through a tissue. The adjustable loop is passed through the tissue. The fastener is passed back through the adjustable loop to fold the adjustable loop upon itself. The fastener is attached to the bone. An adjusting arm on the flexible construct is engaged to reduce the size of the adjustable loop and secure the soft tissue to the bone.

Abstract: Fixation guide devices and methods for positioning and inserting an intramedullary nail are disclosed. The fixation guide devices include a frame with a first end and a second end, a compression device removably coupled to the first end of the frame, and the intramedullary nail secured to a nail attachment apparatus of the frame. An intramedullary nail including a body with a fastening end, a closed end, and at least two openings is also disclosed. A compression device includes a compression member, a knob, and a bolt secured in the knob and rotatably engaging the compression member is also disclosed. An alignment guide is disclosed and includes a base member, an alignment member, and a fixation guide. A method of inserting an intramedullary nail into two bones for fixation of the two bones is also disclosed.

Abstract: In one embodiment, a strike instrument that couples to an insertion handle of an intramedullary nail has a shaft that extends along a shaft axis, and an abutment that extends outward relative to the shaft. The abutment is rotationally fixed to the shaft such that the shaft can rotate the abutment between a first orientation, where the abutment can be removed or inserted into the insertion handle, and a second orientation, where the abutment forms an interference with the insertion handle that prevents the abutment from being removed from the handle. The strike instrument includes a strike surface that can transfer an impaction force to the insertion handle, and a lock that engages the insertion handle so as to prevent the abutment from rotating from the second orientation to the first orientation after the abutment is rotated within the insertion handle from the first orientation to the second orientation.

Abstract: Various exemplary methods and devices are provided for the delivery of spinal screws to a spinal implant site. A variety of exemplary configurations and implementations are provided, but, in general, a handheld tool is provided having a guide member with a lumen formed therein that is configured to deliver a spinal screw to a cervical spine implant. The tool can include various features that facilitate the delivery of the spinal screw to the implant. The tool can include a storage component, such as a magazine, that is configured to hold a plurality of spinal screws for delivery of multiple spinal screws during a surgical procedure.

Abstract: A tissue anchor is provided for use with a valve-repair implant configured to be coupled to cardiac tissue of a patient. The tissue anchor includes a distal tissue coupling element configured to couple the tissue anchor to the cardiac tissue of the patient. It further comprises a proximal implant-penetrating element configured to penetrate at least a portion of the valve-repair implant and facilitate coupling of the valve-repair implant to the tissue anchor. The proximal implant-penetrating element includes an implant-restraining element coupled to a portion of the implant-penetrating element. The implant-restraining element is configured to restrain the valve-repair implant from separating from the implant-penetrating element. Other applications of the present invention are also described.

Abstract: Devices, systems, and methods for locking a drill guide into a polyaxial hole while maintaining the form and function of the polyaxial hole are provided herein. In some embodiments, the drill guide includes a hollow outer body extending from a proximal end to a distal end and having a slot disposed proximate the proximate end, wherein the distal end is configured as a reverse collet having a plurality of prongs; an inner body having a central channel extending therethrough; and a lever coupled to the inner body through the slot, wherein the slot is shaped such that rotation of the lever results in motion along a central axis of the drill guide, and wherein a distal end of the inner body is configured to prevent radially inward deflection of the plurality of prongs when the inner body is in a lowermost position.

Abstract: Anchor assemblies for endovascular introduction and implantation for tethering a replacement heart valve to a cardiac wall. An anchor delivery system introduces the assembly. The anchor may be either implanted with a tether connected thereto or implanted and then connected to a tether. If the latter, a tether assembly is mounted to the implanted anchor to connect the anchor to the valve. The anchors may be implanted into any cardiac wall including the interventricular septum or the epicardial space and the valve may replace the mitral or tricuspid valve.

Abstract: Screw inserter instruments and methods for implanting a bone screw are disclosed herein. In one exemplary embodiment, a screw inserter instrument can include a driver shaft, a retaining sleeve disposed around the driver shaft, and a locking sleeve disposed around the retaining sleeve. The locking sleeve can have a first position in which rotation of the driver shaft causes corresponding rotation of the retaining sleeve while the locking sleeve is held stationary, and a second position in which rotation of the locking sleeve causes corresponding rotation of the retaining sleeve while the driver shaft is held stationary.

Abstract: An intervertebral spacer inserter includes a sleeve having a longitudinal axis, a hollow sleeve bore extending through the sleeve along the longitudinal axis, a sleeve tip end and an opening of a passage disposed in the sleeve tip end. The passage extends into the sleeve to the sleeve shaft along a passage axis that intersects the longitudinal axis at an angle less than about 90°. A sliding tip with an elongated slot is in contact with the sleeve tip end and is moveable with respect to the sleeve tip end between a first position with the opening accessible through the elongated slot and disposed adjacent a first end of the elongated slot and a second position with the opening accessible through the elongated slot and disposed adjacent a second end of the elongated slot opposite the first end.

Abstract: An improved implant inserter, and method of using same, with an elongated, substantially rigid shaft having a proximal surface which is capable of receiving a driving force, and a substantially rigid tip portion having a distal end and a proximal end. At least the distal end of the tip portion is capable of being placed within an implant such as a suture anchor. The inserter further includes a compliant region disposed between the tip portion and the shaft which requires less lateral force to bend than the tip portion, at least when the tip portion has been placed within the implant.

Abstract: A bone positioning guide may include a main body member, a shaft, and a bone engagement member. The shaft can be movably connected to the main body member and have the bone engagement member rotatably coupled to its distal end. The bone engagement member can have a surface configured to engage a bone. The main body member can also include a tip opposite the bone engagement member for engaging a second bone. In use, the bone engagement member may be positioned in contact with a medial side of a first metatarsal while the tip is positioned in contact with a lateral side of a different metatarsal, such as a second metatarsal. The shaft can then be moved to advance the bone engagement member toward the tip, causing realignment of the first metatarsal.

Abstract: An atrial sealing skirt for transcatheter valves and an atrial sealing skirt with an integrated valve to reduce paravalvular regurgitation, with or without the presence of intracardiac leads. The atrial sealing skirt includes a top brim which is positioned to conform to the atrial floor at the deployment site.

Abstract: An implantable pulse generator is provided that includes a power source, a wireless communication component configured to facilitate wireless communication with a non-implanted device and pulse-generating circuitry connected to the power source. The pulse-generating circuitry can be configured to identify, based on wireless communication with the non-implanted device, temporal and amplitude characteristics for electrical pulse stimuli and to trigger electrical output stimuli having the temporal and amplitude characteristics. The implantable pulse generation can further include one or more lead connections—each being shaped to engage a lead and electrically connected to the pulse-generating circuitry to enable the lead to deliver at least part of the electrical output stimuli triggered by the pulse-generating circuitry. The implantable pulse generator can further include one or more suture-engagement components, each including one or more holes each having a diameter that is at least 0.1 mm and less than 5 mm.

Abstract: Disclosed herein are methods and devices for securing soft tissue to a rigid material such as bone. A bone anchor is described that comprises an anchor body with expandable tines and a spreader that expands the tines into bone. Also disclosed is a bone anchor that comprises a base and a top such that suture material may be attached to apertures in the anchor top or else compressed between surfaces on the base and top to secure the suture to the anchor. Also described is an inserter that can be used to insert the bone anchor into bone and move the spreader relative to the anchor body attach suture material. Also described is an inserter that can be used to insert the bone anchor into bone and move the anchor top relative to the anchor body or anchor base to attach to or clamp suture material there between.

Abstract: A surgical system includes a sleeve defining a passageway. An adapter is removably coupled to the sleeve. The adapter defines a channel. A delivery device includes a distal end positioned in a channel of the adapter. A bone fastener includes a head and a shank defining a cannula. A distal portion of the adapter is positioned in the shank such that the channel is in communication with a cannula of the shank. A plunger is movably disposed in a lumen of the delivery device. The plunger is configured to move a material through the lumen and the channel and into the cannula. Methods and kits are disclosed.

Abstract: Methods and devices are provided for anchoring a ligament or tendon to bone. In one embodiment, a biceps tenodesis system is provided and includes a sheath inserter tool, an expandable sheath configured to couple to the sheath inserter tool, an expander inserter tool, and an expander configured to couple to the expander inserter tool. The sheath inserter tool is configured to advance the expandable sheath, with a tendon disposed therearound, into a bone hole, and the expander inserter tool is configured to advance the expander through an outer shaft of the sheath inserter tool and to drive the expander into the sheath. The expander is configured to be received within a lumen extending at least partially through the expandable sheath to thereby expand the sheath. In this way, the system delivers the tendon or ligament into the bone hole and locks the sheath and tendon within the bone hole.

Abstract: The invention provides a screw pegging device.

Abstract: Intramedullary nails, aiming guide assemblies, and methods. The aiming guide assembly can include an aiming guide having a collet and a connection bolt configured to engage a connection bolt driver. The connection bolt may be self-retaining and engage with the connection bolt driver in a manner to prevent unintentional disengagement.

Abstract: A surgical instrument includes a first member defining a passageway. The first member includes a first lock and a second lock. A second member is positioned in the passageway. A third member is coupled to the second member. The second member is movable relative to the first member to move the third member between a first position in which the first lock is spaced a first distance apart from the second lock, and a second position in which the first lock is spaced a reduced second distance apart from the second lock. Systems, spinal implants and methods are disclosed.

Abstract: The disclosure provides systems and instruments that allow vigorous compression of two bone structures while minimally impeding visual access to the surgical site. This is achieved by use of a sleeve member that connects a stanchion to a lever. The system includes a stanchion member, a sleeve member dimensioned to at least partially encircle the stanchion member, and a compression lever including. The sleeve and the lever form a pivot point to allow the compression lever to rotate relative to the stanchion member when the sleeve is reversibly placed around the stanchion member.

Abstract: A suture anchor suitable for being fixed in a hard tissue opening with the aid of a material having thermoplastic properties and energy transmitted to the suture anchor for in situ liquefaction of at least part of the material having thermoplastic properties. The suture anchor includes an anchor foot and a thermoplastic sleeve, and the anchor foot includes a system of channels and/or grooves with a mouth in a proximal face of the anchor foot. The thermoplastic sleeve is arranged coaxially to the mouth. The anchor foot also includes a locking element for securing the suture in a non-slideable manner relative to the hard tissue or a securing sleeve for securing the suture. The locking element or the securing element may be secured relative to the anchor foot when the anchor foot is in a fixed state.

Abstract: An access device for accessing an intervertebral disc having an outer shield comprising an access shield with a larger diameter (˜16-30 mm) that reaches from the skin down to the facet line, with an inner shield having a second smaller diameter (˜5-12 mm) extending past the access shield and reaches down to the disc level. This combines the benefits of the direct visual microsurgical/mini open approaches and the percutaneous, “ultra-MIS” techniques.

Abstract: A system for implanting an implant screw into one or more bones of a patient, such as the sacrum and the ilium, can include a rod and a screw. The screw can be generally hollow and have a blunt distal end. The rod can include a threaded and pointed distal end that is inserted through the rod to drive the screw through the bones. Once the screw is at a desired position, the rod can be removed such that the sharp driving edge used to seat the screw does not remain in the bone. The system can further include an extraction tool having a generally hollow body sized to be inserted over the rod and a distally located screw engagement portion configured to engage the screw to adjust positioning of the screw after it is initially seated.

Abstract: The invention relates to a medical instrumentation with a navigation system which comprises an optical detection unit comprising a camera, and a data processing unit coupled to the detection unit, with a medical article and with a marking device which is held directly or indirectly on the article and is positioned in a defined spatial arrangement in relation thereto, or which marking device is comprised by or formed by the article, the location and orientation of the marking device being determinable with the navigation system, it being possible for at least one image of the marking device and the article to be taken by means of the detection unit and for the position and shape of the article to be determined by the data processing unit on the basis of an image. The invention also relates to a method for determining the shape of a medical article.

Abstract: A surgical instrument for correcting spinal deformities includes a tubular body adapted to receive a second instrument through the tubular body. The tubular body forms a transverse passage adapted to receive a longitudinal fixation element through the tubular body. The tubular body further includes first and second arms for connecting the surgical instrument to a vertebral anchor. The first and second arms include one or more anti-splaying features adapted to mate with anti-splaying features on the second instrument to prevent the first and second arms from splaying as the second instrument is inserted into the tubular body.

Abstract: A suture anchor assembly includes a suture anchor and a suture anchor inserter. The anchor includes a flexible distal tip and a rigid proximal anchor body. The distal tip includes a transverse suture eyelet and a cavity formed in a proximal end of the tip. The anchor body includes a lumen extending between proximal and distal ends of the body. The anchor inserter includes a tubular outer shaft and an inner inserter slidably received therein. The anchor assembly is actuatable to move the anchor tip and inner shaft proximally while the outer shaft and anchor body remain in place, urging the proximal end of the anchor tip against the distal end of the anchor body. The proximal end of the tip is deformable to accommodate at least a portion of the distal end of the anchor body within the anchor tip cavity.

Abstract: A spinal construct comprises a first member engageable with a receiver of a first fastener having a shaft fixed with tissue. A second member is engageable with a receiver of a second fastener having a shaft fixed with the tissue. A longitudinal element connects the members. At least one of the members includes a mating element that is releasably engageable with a surgical instrument to manipulate the tissue such that movement of the receivers relative to the shafts is resisted and/or prevented. Surgical instruments, implants, systems and methods are disclosed.

Abstract: The disclosure relates to medical devices and methods of manufacturing medical devices. An orthopedic screw includes a shaft having a proximal end, a distal end, a body extending between the proximal end and the distal end, and a longitudinal axis. A distal thread on an external surface of the shaft extends around the longitudinal axis. A head portion includes a series of cutting teeth that lie on a plane that is perpendicular to the longitudinal axis of the shaft. A distal tip portion defines a cutting edge.