Handheld devices and methods for immediate implant stabilization

Abstract

A handgrip (2) for the amelioration of a recess (56) and for generating or coupling in mechanical energy with a cylindrical collar (4) with a cylindrical jacket surface having an external diameter and having a central recess (42) for receiving a guide pin (8), wherein the guide pin (8) is received movably in the central recess (42), wherein said handgrip (2) is cannulated through its full axial length to allow for the insertion and full penetration of said guide pin (8) as well as, if present, a wire (52) in a cannulation (43) of the guide pin (8), for accurate positioning in the hole to be ameliorated, wherein said handgrip comprises a housing (13) in which an ultrasonic horn (12) is mounted, wherein said ultrasonic horn (12) is cannulated through its full axial length to allow for the insertion and full penetration of said guide pin (8) and wherein the ultrasonic horn (12) at least over a part of its axial length is provided with at least one ring-shaped ultrasonic vibration generating piezoelectric element (16).

Description

[0001] TITLE

[0002] HANDHELD DEVICES AND METHODS FOR IMMEDIATE IMPLANT STABILIZATION

[0003] TECHNICAL FIELD

[0004] The present invention relates to devices and methods for minimally invasive immediate implant stabilization in a recess, in particular in a recess of porous bone structure.

[0005] PRIOR ART

[0006] A large market that is still under-developed by medical device companies is the fixation of implant systems in poor bone quality. Demographic changes in western countries are significantly increasing the prevalence of osteopenia, osteoporosis and diabetes and therefore the incidence of poor bone quality. Osteopenia and osteoporosis affects millions of people in Europe, US and Japan. It’s presence complicates the treatment of bone fractures dramatically, because implants developed for good bone quality fail in compromised bone. The increasing prevalence of diabetes further contributes to challenges because the systemic deficit of vitamin D impacts bone metabolism. Bone fractures caused by rare diseases like osteogenesis imperfecta are also very difficult to treat.

[0007] Particularly from the field concerned with securing implants in recesses in the human or animal body, for example in drilled holes in bones, it is known to screw implants, which for example are provided with a self-tapping thread, into such recesses under application of torque and then to load the implants mechanically while the implant becomes incorporated in the bone by natural healing processes.

[0008] It is likewise known, particularly in the case of recesses provided in particularly porous bone sections, that primary stability may be insufficient, so the stability of the implant in the recess immediately after being screwed in is insufficient before the actual incorporation process has ended.

[0009] In order to solve such problems, it has already been proposed (see, for example, EP 1 363 543) to produce the implant at least partially or even completely from a material that can be liquefied and / or plasticized by mechanical energy. The liquefiable material can be liquefied by mechanical oscillations after the implant has been inserted into the tissue area, and in this way a form-fit connection is produced between bone and implant by virtue of the liquefied and thereafter resolidified material. A disadvantage of such solutions is the fact that very specific implants are needed to be able to carry out such methods. A further disadvantage is that the liquefiable material cannot be introduced in a sufficiently targeted manner into the desired areas and often is dislocated and disappears, for example, in large recesses arranged at the bottom of the recesses, without in the end contributing to the actual primary stabilization.

[0010] The concept of filling recesses in a human body with the aid of a liquefiable material has in principle been known for some time, particularly in the dental field. Thus, US 3,919,775 describes a method for filling and preparing openings with the aid of a liquefiable material which is initially pressed into the opening and which is then liquefied with the aid of a sonotrode, that is to say a device with which mechanical energy in the form of ultrasound can be introduced. The liquefied material then flows into cavities adjoining the recess and closes these cavities. In other fields where technical materials such as wood, plastics, foams, etc. are processed, such techniques are also known in the widest sense.

[0011] Furthermore WO 2009 / 141252 discloses a method and a device for ameliorating a recess, e.g. for preparing the recess for an implant to be fastened in that recess, in particular dental implant.

[0012] Generally in the field of implants US 2008 / 039845 provides a method for stabilizing a fractured bone. The method includes positioning an elongate rod in the medullary canal of the fractured bone and forming a passageway through the cortex of the bone. The passageway extends from the exterior surface of the bone to the medullary canal of the bone. The method also includes creating a bonding region on the elongate rod. The bonding region is generally aligned with the passageway of the cortex. Furthermore, the method includes positioning a fastener in the passageway of the cortex and on the bonding region of the elongate rod and thermally bonding the fastener to the bonding region of the elongate rod while the fastener is positioned in the passageway of the cortex. Inter alia the document discloses the use of a guide wire for introducing the structure to be implanted in a hole of the bone or of the tissue. There is however no disclosure of using a guide wire in the context of positioning a secondary tool of an implantation process which secondary tool is removed after the actual implantation process.

[0013] WO-A-2017102433 discloses a system for the amelioration of a recess, particularly of a recess in a porous, perforate material having cavities freed by the recess, said system comprising an element for generating or coupling in mechanical energy, and a cylindrical collar having a central recess for receiving a guide pin, wherein the guide pin, having a cannulation, is provided to be inserted substantially as far as the bottom of the recess under positioning using a wire before mechanical energy is applied, wherein the guide pin, in the area of the end thereof directed toward the bottom of the recess, is surrounded by an amelioration sleeve, wherein the external cylindrical jacket surface of the amelioration sleeve has substantially the same external diameter as the collar, and wherein the guide pin is received movably in the central recess such that, when mechanical energy is applied, the collar can be moved relative to the guide pin in the direction toward the bottom of the recess while liquefying and laterally and / or longitudinally displacing the material of the amelioration sleeve.

[0014] CN-U-217310486 provides a transducer and ultrasonic osteotome handle as an ultrasonic bone knife handle, the transducer comprises a body and an amplitude transformer connected to the front end of the body, the body comprises a pre-tightening bolt, and a front cover plate, a rear cover plate and a piezoelectric assembly which are connected to the pretightening bolt; wherein the front end of the pre-tightening bolt is sequentially connected with the amplitude-change pole and the front cover plate, the piezoelectric assembly is located between the front cover plate and the rear cover plate, the rear cover plate is connected to the rear end of the pre-tightening bolt, and the rear cover plate is provided with a tightening part with a hexagonal cross section. According to the utility model, the universality of disassembly and assembly of the rear cover plate is enhanced, and the rear cover plate connected to the pre-tightening bolt can be disassembled and assembled by adopting a size wrench with a corresponding specification on the market; in addition, a special dismounting tool is prevented from being machined and manufactured, and the cost is reduced.

[0015] US-B-6204592 proposes an ultrasonic nailing and drilling apparatus for various precision use, such as medical or dental surgery, which comprises piezoelectric transducer means to give an axial thrust and a motor to give a rotation to a bit. Therefore, this ultrasonic nailing and drilling apparatus combines the best of the ultrasound nailing or drilling bit and the best of the rotational drill. The ultrasonic nailing and drilling apparatus further comprises an elongated horn having an operative tip, wherein a bit can be fixedly attached. The operative tip can be in any form designed for ultrasonic machines, and even can be in a similar shape as a flat screwdriver tip, as a Phillips head tip, or even as a conventional drill bit.

[0016] CN-ll-212307953 relates to a waterproof transducer for use as such as ultrasonic scaler and bone knife which comprises an amplitude-change pole, a piezoelectric module, a main pole, a water pipe, two O-shaped rings, the tail end of the amplitude-change pole is narrowed into a tubular inserting rod, and the tail end of the inserting rod is inserted into the main pole from the front end of the main pole and is in threaded connection with the main pole; the piezoelectric module is arranged on the inserting rod in a sleeving manner and is clamped by the amplitude-change pole and the main rod; one end of the water pipe enters the inserting rod through the tail end of the inserting rod, and the other end of the water pipe extends out of the main rod through the interior of the main rod; and O-shaped rings are respectively arranged between the peripheral surface of the water passing pipe and the inner wall of the inserting rod and between the peripheral surface of the water passing pipe and the inner wall of the main rod. The amplitude transformer has the beneficial effects that the piezoelectric module is arranged on the inserting rod of the amplitude transformer instead of the main rod, so that the amplitude transformer is more convenient to install; waterproof performance.

[0017] SUMMARY OF THE INVENTION

[0018] It is an object of the present invention to provide an improved handgrip for an amelioration process of a recess.

[0019] According to a first aspect of the present invention it correspondingly relates to a handgrip for the amelioration of a recess, particularly of a recess in a porous, perforate material having cavities freed by the recess, and for generating or coupling in mechanical energy with a cylindrical collar with a cylindrical jacket surface having an external diameter and having a central recess for receiving a guide pin.

[0020] The guide pin is received movably in the central recess such that, when mechanical energy is applied, the cylindrical collar can be moved relative to the guide pin in the direction toward the bottom of the recess while liquefying (including plasticizing) and laterally and / or longitudinally displacing the material of an amelioration sleeve made from a material that can be liquefied (including plasticized) by mechanical energy and which material of the amelioration sleeve is surrounding said guide pin.

[0021] The guide pin has an axial central through bore in the form of a cannulation for receiving a wire inserted into said cannulation of the guide pin at least before mechanical energy is applied. The cannulation in the guide pin is just for the wire and / or in the handgrip for the guide pin, so it preferably has a rather small diameter (typically in the range of 0.5-3 mm as for a wire, in particular a K-wire or a diameter in the range of 1.5-10 mm as for a guide pin) and is normally not suitable for guiding a liquid, so it may have an internal side wall which is not circumferential and contiguous over the full length and / or is not sealing.

[0022] Also said handgrip is cannulated through its full axial length to allow for the insertion and full penetration of said guide pin as well as said wire in said cannulation of the guide pin for accurate positioning in the hole to be ameliorated.

[0023] The cylindrical collar is normally part of the handgrip, and preferably also at least one of the guide pin and the wire and the amelioration sleeve.

[0024] The handgrip is provided for the amelioration of an opening and is not suitable and adapted as a drilling or sewing or nailing device, and preferably also does not comprise interfaces for such cutting, erosive or ablative, or hammering applications.

[0025] Further said handgrip comprises a housing (to be held by the user) in which an ultrasonic horn is mounted. Typically, such a housing is made from a thermoplastic material, which can be glass fiber reinforced. Possible materials are polypropylene (PP), polyamide (PA), polycarbonate (PC), polyvinyl chloride (PCV), polyether ether ketone (PEEK), or mixtures thereof. The housing can consist of two or more parts which are fixed to each other, either by a form closure, force fit, material connection or a combination thereof, so e.g. a clipping connection, groove and comb, screws, gluing, or welding, or a combination thereof. Two halves of the housing can be separated by an axial or radial plane.

[0026] Said ultrasonic horn is cannulated through its full axial length to allow for the insertion and full penetration of said guide pin as well as said wire in said cannulation of the guide pin.

[0027] The ultrasonic horn at least over a part of its axial length is provided with at least one ringshaped ultrasonic vibration generating piezoelectric element.

[0028] According to a preferred embodiment of the proposed handgrip, there is provided more than one ring-shaped ultrasonic vibration generating piezoelectric element, and preferably the ring-shaped ultrasonic vibration generating piezoelectric elements are located axially adjacent to each other, wherein preferably at least 2 or 3 or exactly 2 or 3, preferably identical, ring-shaped ultrasonic vibration generating piezoelectric elements are provided in axial series.

[0029] According to a preferred embodiment of the proposed handgrip, at least one ring-shaped ultrasonic vibration generating piezoelectric element is provided behind a main portion of the ultrasonic horn, and is, or in case of more than one ring-shaped ultrasonic vibration generating piezoelectric element are, surrounded by or surrounding a backside extension of the ultrasonic horn with smaller diameter than the main portion, preferably directly adjacent to a radially extending shoulder between the main portion and the backside extension, wherein preferably between the cylindrical outer surface of the backside extension and a cylindrical inner surface of the ring-shaped ultrasonic vibration generating piezoelectric element there is provided at least one sleeve, preferably comprising or consisting of a polymeric damping material, preferably as a heat shrink sleeve.

[0030] According to a preferred embodiment of the proposed handgrip, the ultrasonic horn is made of titanium or a titanium alloy or a steel or steel alloy, and preferably comprises a front extension with an outer threading or bayonet lock, preferably penetrating at least partly beyond a front section of said housing, acting as an interface for the attachment of a cylindrical collar provided with a corresponding backside recession with internal threading or bayonet lock.

[0031] According to a preferred embodiment of the proposed handgrip, the ultrasonic horn is mounted in the handgrip in a vibration damping manner, preferably in that there is an axial or radial interspace between a preferably cylindrical wall portion of the housing and there is provided at least one vibration damping mounting element in that radial or axial interspace, preferably a series of vibration damping mounting elements along the axial direction of the handgrip, wherein preferably the vibration damping mounting element is selected as an elastic O-Ring According to a preferred embodiment of the proposed handgrip, in a backside portion of the handgrip there is provided, in the housing or as part thereof, a backside guiding element with a through opening for the guide pin as well as the wire, wherein preferably this backside guiding element can be made from the same material as the ultrasonic horn or the housing and / or is mounted by at least one vibration damping mounting elements in the housing or is part of the housing.

[0032] One serious problem that was identified with such handgrips is that in the context of cleaning and sterilization thereof such handgrips are typically exposed to elevated temperatures and pressure over an extended period of time. Also steam treatment is often used. If the interior of the corresponding handgrip is not sealed, cleaning and sterilization will typically lead to condensation of water in the inside of the housing, and eventually will lead to corrosion of the metal parts, in particular of the ultrasonic horn and / or the piezoelectric elements. This is why the sealing aspect is important, preferably it is combined with filling the interior with an inert gas. An alternative approach in this respect is the provision of venting openings enabling complete drying at the end of the cleaning and / or sterilization process.

[0033] According to a preferred embodiment of the proposed handgrip, between the housing and the ultrasonic horn sealing elements are provided, in particular at the interface between a front opening of the housing and a lateral front contact portion or an edge portion thereof of the ultrasonic horn, and wherein preferably in addition, in the presence of a backside guiding element , there are provided sealing elements at the interface between a backside opening of the housing and a backside or radial surface of the backside guiding element.

[0034] According to a preferred embodiment of the proposed handgrip, the cannulation of the ultrasonic horn is provided with a mounting tube, which preferably extends between a tip portion of the ultrasonic horn and a backside opening of the housing and / or the backside opening, in the presence of a backside guiding element, of such backside guiding element, wherein preferably said mounting tube is made of a polymer material, preferably partly or fully halogenated polymer material, most preferably PTFE material.

[0035] This mounting tube has the following two effects: it can be used for further decoupling of the vibrational energy between the guide pin and / or the (K-)wire and the ultrasonic horn, but it also can be used for optimum sealing not only of the interior of the housing but also of the through opening of the ultrasonic horn.

[0036] The mounting tube can be sealed by way of circumferential sealing elements at least at the front opening of the ultrasonic horn, where the mounting tube is essentially flush with a front extension of the ultrasonic horn, and / or preferably the mounting tube is sealed by way of circumferential sealing elements with respect to the housing or, if present, with respect to a backside guiding element.

[0037] Also, the housing can be provided with at least one venting opening.

[0038] Further the housing can be sealed and any cavity thereof can be filled with inert gas, in particular nitrogen gas.

[0039] According to a preferred embodiment of the proposed handgrip, it comprises a bar shaped element essentially coaxial with the cylindrical collar as well as, branching off from that bar shaped element, preferably under an angle in the range of 90-60°, a gripping extension to be held by the user, wherein preferably said gripping extension is provided with manual actuating elements for controlling the energy transmitted by the cylindrical collar.

[0040] According to a preferred embodiment of the proposed handgrip, the guide pin is made of synthetic polymer material, preferably of a thermoplastic material, in particular PTFE and / or PFA, which optionally can be radio-opaque, and / or wherein the guide pin has an outer diameter in the range of 1.5-10 mm, preferably in the range of 2-4 mm, particularly preferably in the range of 2.5-3.5 mm, and wherein diameter of the cannulation is in the range of 0.5-3 mm, preferably in the range of 1-2 mm, particularly preferably in the range of 1.3-1.75 mm.

[0041] The external diameter of the collar can be in the range of 1-80 mm, preferably in the range of 2-10 mm, and the external diameter of the guide pin can be 0.1 - 20 mm less, preferably 0.1-2 mm or 0.5-1 mm less.

[0042] The amelioration sleeve can have a thickness such that the external diameter thereof is the same as the external diameter of the collar and the internal diameter preferably larger than the external diameter of the guide pin, wherein the amelioration sleeve, at least in some sections, preferably has a wall thickness in the range of 0.1-1 mm, preferably in the range of 0.2-0.6 mm.

[0043] According to a preferred embodiment of the proposed handgrip, it generates mechanical energy in the form of vibration energy and / or oscillation energy with frequencies in the range of 1 kHz - 10 GHz, preferably in the form of ultrasonic oscillations in the frequency range of 10 kHz - 100 MHz or 20-150 kHz, particularly preferably in the range of 20 - 70 or 20-40 kHz, which are transmitted in the longitudinal, transverse or rotational direction, or in a combination or linear combination of these directions, preferably substantially exclusively in the longitudinal direction, to the collar (and / or guide pin) and thus (indirectly) to the amelioration sleeve.

[0044] The wire is typically a preferably sterilized stainless steel pin, preferably having a sharpened tip at least at one end, with preferably circular cross-section over essentially its full-length, and having a diameter in the range of 0.4-3 mm, preferably in the range of 0.9-1.9 mm, more preferably in the range of 1.25-1.7 mm.

[0045] According to another aspect the present invention relates to a method for operating a handgrip as detailed above. That method can be a surgical or non-surgical method.

[0046] More specifically the method is characterized in that a wire is centrally inserted into a recess and pushed into the very bottom thereof, if needed the inner surface of the recess is prepared for amelioration by using a reamer with a central cannulation, which cannulation is pushed over said wire for controlled insertion of the reamer into the recess, the reamer being rotated when positioned in / advanced into the recess until the desired preparation of the recess is terminated, and subsequently the reamer is taken out while keeping the wire in place, if needed an insertion device having an amelioration sleeve mounted at the distal tip portion thereof and having a central cannulation is pushed with said cannulation over said wire for controlled insertion of the insertion device with the amelioration sleeve into the recess and positioning the amelioration sleeve in the bottom region of the recess, and subsequently taking out the insertion device while keeping the amelioration sleeve in the recess and keeping the wire in place, the guide pin is pushed with or by using its cannulation over said wire for controlled insertion of the guide pin and for insertion of the distal portion thereof into the positioned amelioration sleeve in the recess if an insertion device has been used, or for inserting the amelioration sleeve together with or after the guide pin, wherein the recess has an internal diameter corresponding substantially to the external diameter of collar and amelioration sleeve, until the guide pin abuts against the bottom of the recess and / or engages in a guide taper arranged at the bottom of the recess, and then, with simultaneous liquefying (including plasticizing) of the amelioration sleeve by applied mechanical energy, preferably by applied ultrasound, if needed using a protection sleeve for protecting surrounding soft tissue, and with pushing of the distal end of the collar of the handgrip into the recess, liquefied (including plasticized) material is introduced into cavities, particularly lateral cavities, adjoining the recess.

[0047] Preferably, the method is a non-surgical method.

[0048] The recess is normally a recess in an at least partially porous technical material, including wood or wood-like material, or foam material, particularly a polymer foam, a composite foam and / or a metal foam, or in an at least partially dead or living porous human or dead or living animal bone section, particularly in a jaw bone or a spinal column bone, and in that the recess is preferably generated at least partially by preliminary drilling.

[0049] Further embodiments of the invention are laid down in the dependent claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Preferred embodiments of the invention are described in the following with reference to the drawings, which are for the purpose of illustrating the present preferred embodiments of the invention and not for the purpose of limiting the same. In the drawings, Fig. 1 shows the kit of parts;

[0051] Fig. 2 shows the individual steps when using the device for amelioration of an opening

[0052] Fig. 3 shows a first embodiment of a handgrip according to the invention in a schematic axial cross-section with mounted sonotrode and backside guiding element, with guide pin and K-wire inserted;

[0053] Fig. 4 shows a second embodiment of a handgrip according to the invention in a schematic axial cross-section with a separate mounting tube and backside guiding element;

[0054] Fig. 5 shows a third embodiment of a handgrip according to the invention in a schematic axial cross-section with a separate mounting tube without backside guiding element;

[0055] Fig. 6 shows a fourth embodiment of a handgrip according to the invention in a schematic axial cross-section with venting openings.

[0056] DESCRIPTION OF PREFERRED EMBODIMENTS

[0057] Fig. 1a) shows an immediate stabilization system with the components for the immediate stabilization augmentation process. The ultrasonic (US) generator 1 , the handgrip 2 with a covering ring 3 (optional), the sonotrode 4 (collar) and the ISS (immediate stabilization system) sleeve 7 together with the guide pin 8 represent the core-components of the system. The US generator 1 supplies the handgrip 2 (converter) via cable 1a (e.g. sealed to the housing) with electrical power of the required amplitude and frequency, which then is converted in the handgrip 2 into a mechanical oscillation. The mechanical oscillation is directed to the sonotrode 4 that oscillates with a particular amplitude and supplies the (non- resorbable or resorbable, e.g. polylactide) ISS sleeve 7 with the power / energy necessary for melting the material and displace it into the adjacent trabecular bone structure. Pre- clinical tests have shown that this leads to an enhanced mechanical stability of the surrounding bone structure.

[0058] Furthermore, the system may include an insertion device 5, a reamer 6, the cleaning device 9 and a torque key 10. Also and advantageously, the ultrasound generator can be controlled by the operator using a foot pedal 11 (or alternatively a control on the handgrip) controlling the amount of energy generated by the ultrasound generator and transferred to the handgrip 2 and transmitted to the sonotrode 4. Fig. 1 b) shows a different embodiment, where the handgrip 2 as opposed to the bar shaped design in Fig. 1a is provided, apart from the bar shaped element 2a which is axial with the sonotrode 4, with a pistol grip like gripping extension 2b for the user to grip by the hand during operation. That gripping extension 2b is typically aligned relative to the bar shaped 2a element of the handgrip 2 under an angle in the range of 60-90°, and the gripping extension 2a may have manipulation elements to control the US generator, i.e. to control duration and / or amplitude of the ultrasonic vibration generated at the sonotrode. An advantage of this design is inter alia that the cable 1a can be routed via the end of this gripping extension 2a which makes manipulation easier and more intuitive. The handgrip 2 may comprise electronics and even control, to allow for control lights, control displays etc. Also illustrated in that Fig. 1 b) is that the handgrip 2 is cannulated over the full length of the bar shaped 2a element for the guide pin 8 as well as for the K-wire 52 as will be detailed further below.

[0059] In the following it shall be illustrated how the proposed method and device for minimally invasive amelioration can be used in detail in the context of Fig. 2.

[0060] As illustrated in Fig. 2a), the method comprises a step of pedicle opening in the vertebra element 53 and channel preparation. Once the access to the pedicle has been exposed, a channel has to be created through the pedicle by means of any standard surgical procedure. To enable a guided operation procedure, a K-wire (Kirschner Wire) 52 is introduced into the existing channel 56.

[0061] The method then typically comprises a step of implant bed preparation as illustrated in Fig. 2b). The existing pedicle channel is expanded in diameter by means of the ISS reamer 6 for ensuring a precise implant bed. Therefore, the ISS reamer 6 is guided over the previously placed K-wire 52. The reamer 6 is slightly pressed forward, into the pedicle channel, while it is rotated until the final placement depth of the pedicle screw is reached. The final depth can be recognized by the depth scale which can be provided on the shank of the reamer.

[0062] The next optional step as illustrated in Fig. 2c) is the step of ISS sleeve placement. The ISS sleeve 7 is attached to the smaller cylinder at the tip of the ISS insertion device 5.

[0063] Then, as illustrated in Fig. 2d), showing the ISS sleeve insertion, the ISS sleeve 7 is placed at the bottom of the implant bed by means of the insertion device 6, guided over the K-wire 52, controlling the insertion depth by the markings on the insertion device 6. Subsequently, the ISS insertion device 6 can be easily removed, leaving the ISS sleeve 7 on its place. The depth scale indicates at which depth the ISS sleeve should be placed referring to the length of the later implanted pedicle screw and in relation to the prepared implant bed depth (by the reamer). Alternatively, the guide pin is placed and then thereafter manually the sleeve is shifted over the guide pin.

[0064] In the next step, as illustrated in Fig. 2e), showing the insertion of the guide pin, the ISS guide pin 8 is inserted into the implant bed and through the ISS sleeve 7 at the end of the pedicle channel. The accurate positioning is ensured by the positioned K-wire 52. Due to the cannulation of the handgrip 2 the guiding pin 8 can also be much longer than illustrated in that figure, such that it penetrates substantially into and even beyond the handgrip 2 (see also Fig. 1a).

[0065] The next step can be the step of temporary removal of the K-wire, as illustrated in Fig. 2f). However, that step is not necessary, in order to perform the ISS melting process, the K-wire 52 can also stay in place, also due to the cannulation of the handgrip 2.

[0066] In the next step as illustrated in Fig. 2g), showing the initiation of the sonotrode oscillation. Before starting the US oscillation, the sonotrode 4 on the handgrip 2 is placed slightly over the ISS sleeve 7 inside the implant bed. At the moment of activation, preferably, the sonotrode 4 should be free from any fixation or other external forces for ensuring a successful settling of the sonotrode ultrasound oscillation. Typically, the sonotrode is already in contact with the sleeve when ultrasound is activated (the sonotrode is used to push the sleeve down the implant bed before activating ultrasound). A significant advantage of the full cannulation of the handgrip in this phase is that the K-wire 52 can stay in place fully surrounded by the guide pin 8 penetrating through the handgrip 2, leading to an optimum positioning and without problems keeping the K-wire 52 in place due to the ultrasound insulation between handgrip 2 and K-wire 52 by way of the guide pin 8. Insulation in the transducer can also be ensured by means of the mounting tube discussed below.

[0067] In the next step as illustrated in Fig. 2h) of the melting of the ISS sleeve, the ultrasound energy is activated by operating the foot pedal or via an actuator on the handgrip 2. Simultaneously, the sonotrode 4 needs to be slightly pressed down for melting the ISS sleeve 7 into the surrounding trabecular bone structure. The ultrasound oscillation will continue as long as the foot pedal / an actuator on the handgrip is operated but typically not longer than 5-8 seconds, depending on the dimensions of the sleeve. A depth scale is provided at the lateral surface of the sonotrode 4, indicating the depth which has to be integrated into the bone for ensuring a successful melting of the entire ISS sleeve.

[0068] In the next step of removing the sonotrode as illustrated in Fig. 2i) approximately 5 seconds after the ultrasound energy was deactivated again, the molten polymer is re-solidified. By slightly turning the handgrip 2, the sonotrode 4 will be detached from the molten ISS sleeve and the sonotrode 4 can be easily removed from the implant bed. Preferably, at the same time the ultrasound energy is activated shortly to detach the sonotrode from the solidified polymer. The next step can be a step of re-insertion of the K-wire 52 as illustrated in Fig. 2k) if the K-wire 52 has been removed temporarily. After the ISS melting process has successfully been completed, the K-wire in this case can be re-positioned through the remaining guiding pin 8. Thereafter, the guiding pin 8 is removed from the implant bed via the inserted K-wire 52. In case, as preferred, the K-wire 52 has not been removed during the ultrasonic treatment with a cannulated handgrip 2, this step can be omitted and at the same time the sonotrode 4 and the guide pin 8 can be removed in the step as illustrated in Fig. 2i) in a backwards motion while keeping the K-wire 52 in place in the opening to be ameliorated. Then follows the step of pedicle screw implantation as shown in Fig. 2I). The pedicle screw 55 implantation can now be done, following the usual standard surgical procedure for the corresponding implant system.

[0069] Fig. 2m) shows the finally augmented pedicle screw. After the K-wire 52 has been removed the implantation including the ISS pedicle screw augmentation is completed.

[0070] Fig. 3 shows a first embodiment of a handgrip 2 according to the present invention. In this case the sonotrode 4 is mounted on the handgrip 2. The sonotrode 4 has an outer external tip diameter 41 and is provided with a circular cylindrical central recess 42 for receiving the guiding pin 8. The guiding pin 8 itself has an axial central cannulation 43 for the K-wire 52. The guiding pin 8 and the K-wire 52 extent not only through the sonotrode 4 but also through the whole of the handgrip 2 as can be seen in that illustration.

[0071] The sonotrode 4 Is mounted on the handgrip 2 in such a way that it is attached and firmly secured to an ultrasonic horn 12, which is located in the housing 13 of the handgrip. This ultrasonic horn 12 is used for amplifying the ultrasonic vibrations which are initially generated by the circular piezoelectric elements 16 which sit on and enclose a backside extension 21 of the ultrasonic horn 12. This backside extension 21 follows on a main portion 22 of the ultrasonic horn 12, which main portion has a larger diameter than the backside extension 21. Between the main portion 22 and the backside extension 21 there is a radial shoulder 23, on which the frontmost circular piezoelectric element is abutting. In this case there is an axial series of three identical circular cylindrical ring like piezoelectric elements 16, which with their cylindrical inner surface 47 sit on the cylindrical outer surface 46 of the backside extension 21 .

[0072] On the front side, the ultrasonic horn 12 is provided with a front extension 17 which acts as an interface to the sonotrode 4. To this end the front extension is provided with an external threading to cooperate with an internal threading provided on a backside recession 18 of the sonotrode 4. The sonotrode 4 is screwed onto the ultrasonic horn by way of this interface 17 / 18, typically such that the backside radial surface of the sonotrode 4 firmly abuts and contacts a lateral front contact portion 20 of the ultrasonic horn 12. This way the ultrasonic waves are not only guided by the ultrasonic horn 12 but also amplified in that element and also, by way of corresponding converging structuring of the sonotrode 4, also by that sonotrode 4. The sonotrode by way of the interface 17 / 18 can be replaced and / or repaired and / or exchanged depending on what kind of diameters etc. are needed rather easily.

[0073] As mentioned above, the handgrip is fully cannulated and so is the ultrasonic horn 12 including its main portion 22 and the backside extension 21. At the backside of the backside extension 21 to facilitate insertion of the guiding pin from the backside that can be provided a funnel structure 25 as illustrated in that figure.

[0074] To make sure that the guiding pin and the K wire are safely guided in the handgrip on the backside in the housing 13 there is provided an additional backside guiding element 26, which can also be part of the housing 13.

[0075] Both the ultrasonic horn 12 as well as the backside guiding element 26 are mounted such that between their outer circumference and the cylindrical wall of the housing 48 there is an interspace 14. The ultrasonic horn 12 and the backside guiding element are mounted in that cylindrical wall by way of vibration damping mounting elements 15 of the ultrasonic horn and optional vibration damping elements 27 of the backside guiding element 26, respectively. Vibrations generated by the ultrasonic horn are thereby optimally damped relative to the housing facilitating manipulation without disturbing vibrations of the handgrip. Also, the backside guiding element 26 is provided with a cannulation 43 such that the guiding pin 8 as well as the K-wire 52 can extend and penetrate through the full handgrip 2. Also the housing to this and has a front opening 19 and a backside opening 28.

[0076] Fig. 4 shows another embodiment of the proposed handgrip. In this case the cannulation in the handgrip is not directly an exposed part of the ultrasonic horn and / or the backside guiding element, but there is a mounting tube 29 which is located in the respective openings 43 and 45. One problem with handgrips of this type can be corrosion induced by remnant humidity from cleaning and sterilization processes. This may affect any metal surface which is not protected, and one possibility to tackle that problem is the provision of a mounting tube 29 as illustrated in that Fig. 4. The mounting tube extends between the very top portion of the ultrasonic horn 12, i.e. typically abuts with the front surface of the front extension 17, where it is sealingly connected to the ultrasonic horn extension 17 by way of sealing elements 30, for example O-rings. At the backside the mounting tube 29 abuts with the backside opening 35 of the backside guiding element 26, and also there sealings are provided in the form of sealing rings 36. To provide for a complete sealing of the hollow interspace inside of the actual housing wall 13, further sealing elements 32 are provided at the interface between the housing 13 and the radial outer portion of the backside guiding element. Alternatively, also a sealing to the backside of the backside element is possible. On the front side further sealing elements 31 are provided at the interface between the housing wall 13 and in the region of the radial outer edge of the lateral front contact portion 20 of the ultrasonic horn.

[0077] In this case furthermore there is provided a sleeve 40 between the piezoelectric ring elements and the cylindrical outer surface 46 of the backside extension 21. Typically, this can be a heat shrinking sleeve to provide for optimum conditions.

[0078] Also, in this case the backside extension 21 extends in a backside direction beyond the piezoelectric rings. It is also possible that in this protruding portion the diameter of the backside extension 21 is increasing again or that a ring of ultrasonic horn material is mounted on that backside portion 24. The corresponding mass can act as a counter mass for balancing of the total ultrasonic horn to provide for optimum resonating conditions.

[0079] The hollow space in the housing 13 in this case is sealed by the sealing element combination 30-32 as well as 36, and to increase protection also the void space in the housing can be filled with an inert gas.

[0080] Fig. 5 shows another embodiment similar to the one illustrated in the preceding figure. In this case however the backside guiding element 26 is omitted. In this case therefore the mounting tube 29 extends to a small and narrow backside opening 28 of the handgrip, and again at this terminal position sealing elements 37 are provided to make sure that the void space is safe in case of sterilization and subsequent cooling in particular.

[0081] Another approach to tackle the sterilization problem is illustrated in the embodiment shown In Fig. 6. In this case instead of providing a mounting tube 29 and corresponding sealing elements venting openings 38 are provided in the wall of the housing 13, so that any humidity accumulated or generated during or after cleaning and sterilization can escape and will not generate corrosion problems. Venting openings are preferably designed in such a way that the operator cannot get in direct contact with the inner parts and so that cleaning of pollution from the surgery / during use is possible.

[0082] LIST OF REFERENCE SIGNS

[0083] 1 ultrasound generator 6 reamer

[0084] 1a cable between 1 and 2 7 amelioration sleeve

[0085] 2 handgrip stabilization sleeve

[0086] 2a bar shaped element of 2 8 guiding pin

[0087] 2b gripping extension of 2 9 cleaning device

[0088] 3 covering ring 10 torque key

[0089] 4 sonotrode 11 foot pedal

[0090] 5 insertion device 12 ultrasonic horn housing 13 / 28 radial interspace between 12 33 backside insertion funnel of and 13 26 vibration damping mounting 34 front opening of 29 of 12 in 13 35 backside opening of 29 circular piezoelectric element 36 sealing between 29 and 26 interface to 4, front extension 37 sealing between 29 and with threading 13 / 28 interface to 12, backside 38 venting opening recession with internal 39 through opening through 26 threading 40 sleeve between 16 and 24, front opening in 13 heat shrink sleeve lateral front contact portion 41 external diameter of 4 between 12 and 4 42 central recess of 4 backside extension of 12 43 cannulation of 8 for 52 main portion of 12 44 through opening in 26 for 8 shoulder between 22 and 21, and 52 diameter reduction for 16 45 cannulation of 12 counter mass of 12 46 cylindrical outer surface of 21 backside insertion funnel of 47 cylindrical inner surface of 16

[0091] 12 48 cylindrical wall portion of 13 backside guiding element vibration damping mounting 52 K-wire of 26 in 13 53 vertebra element backside opening in 13 54 stabilization sleeve mounting tube penetrated into porosity of sealing between 12 and 29 surrounding cavity and 53 sealing between 12 and 55 implant, screw

[0092] 13 / 19 56 recess sealing between 26 and

Claims

CLAIMS1. A handgrip (2) for the amelioration of a recess (56), particularly of a recess in a porous, perforate material having cavities freed by the recess (56), and for generating or coupling in mechanical energy with a cylindrical collar (4) with a cylindrical jacket surface having an external diameter and having a central recess (42) for receiving a guide pin (8), wherein the guide pin (8) is received movably in the central recess (42) such that, when mechanical energy is applied, the cylindrical collar (4) can be moved relative to the guide pin (8) in the direction toward the bottom of the recess (56) while liquefying and laterally and / or longitudinally displacing the material of an amelioration sleeve (7) made from a material that can be liquefied by mechanical energy and which material of the amelioration sleeve (7) is surrounding said guide pin (8), wherein the guide pin (8) preferably has an axial central through bore in the form of a cannulation (43) for receiving a wire (52) inserted into said cannulation (43) of the guide pin (8) at least before mechanical energy is applied, wherein said handgrip (2) is cannulated through its full axial length to allow for the insertion and full penetration of said guide pin (8) as well as, if present, said wire (52) in said cannulation (43) of the guide pin (8), for accurate positioning in the hole to be ameliorated, wherein said handgrip comprises a housing (13) in which an ultrasonic horn (12) is mounted, wherein said ultrasonic horn (12) is cannulated through its full axial length to allow for the insertion and full penetration of said guide pin (8) as well as, if present, said wire (52), in said cannulation (43) of the guide pin (8), and wherein the ultrasonic horn (12) at least over a part of its axial length is provided with at least one ring-shaped ultrasonic vibration generating piezoelectric element (16).

2. The handgrip according to claim 1 , wherein there is provided more than one ring-shaped ultrasonic vibration generating piezoelectric element (16), and wherein the ringshaped ultrasonic vibration generating piezoelectric elements (16) are located axially adjacent to each other, wherein preferably at least 2 or at least 3 or exactly 2 or exactly 3, preferably identical, ring-shaped ultrasonic vibration generating piezoelectric elements (16) are provided in axial series.

3. The handgrip according to any of the preceding claims, wherein the at leastone ring-shaped ultrasonic vibration generating piezoelectric element (16) is provided behind a main portion (22) of the ultrasonic horn (12), and is / are surrounded by or surrounding a backside extension (21) of the ultrasonic horn (12) with smaller diameter than the main portion (22), preferably directly adjacent to a radially extending shoulder (23) between the main portion (22) and the backside extension (21), wherein preferably between the cylindrical outer surface (46) of the backside extension and a cylindrical inner surface(47) of the ring-shaped ultrasonic vibration generating piezoelectric element (16) there is provided at least one sleeve, preferably comprising or consisting of a polymeric damping material, preferably as a heat shrink sleeve.

4. The handgrip according to any of the preceding claims, wherein the ultrasonic horn (12) is made of titanium or a titanium alloy, and preferably comprises a front extension (17) with an outer threading or bayonet lock, preferably penetrating at least partly beyond a front section of said housing (13), acting as an interface for the attachment of a cylindrical collar (4) provided with a corresponding backside recession (18) with internal threading or bayonet lock.

5. The handgrip according to any of the preceding claims, wherein the ultrasonic horn (12) is mounted in the handgrip (2) in a vibration damping manner, preferably in that there is an axial or radial interspace (14) between a preferably cylindrical wall portion(48) of the housing (13) and there is provided at least one vibration damping mounting element (15) in that axial or radial interspace (14), preferably a series of vibration damping mounting elements along the axial direction of the handgrip (2), wherein preferably the vibration damping mounting element (15) is selected as an elastic O-Ring (15).

6. The handgrip according to any of the preceding claims, wherein in a backside portion of the handgrip (2) there is provided, in the housing (13) or as part thereof, a backside guiding element (26) with a through opening (44) for the guide pin (8) as well as the wire (52), wherein preferably this backside guiding element (26) is made from the same material as the ultrasonic horn or is part of the housing and / or is mounted by at least one vibration damping mounting elements (27) in the housing (13).

7. The handgrip according to any of the preceding claims, wherein between the housing (13) and the ultrasonic horn (12) there are provided sealing elements (31), in particular at the interface between a front opening (19) of the housing (13) and a lateral front contact portion (20) or a frontal contact portion (20) or an edge portion thereof of theultrasonic horn (12), and wherein preferably in addition, in the presence of a backside guiding element (26), there are provided sealing elements (32) at the interface between a backside opening (28) of the housing (13 and a backside or radial surface of the backside guiding element (26).

8. The handgrip according to any of the preceding claims, wherein the cannulation (45) of the ultrasonic horn is provided with a mounting tube (29), which preferably extends between a tip portion of the ultrasonic horn (12) and a backside opening of the housing (28) and / or the backside opening, in the presence of a backside guiding element (26), of such backside guiding element (26), wherein preferably said mounting tube (29) is made of a polymer material, preferably partly or fully halogenated polymer material, most preferably PTFE material.

9. The handgrip according to claim 8, wherein the mounting tube (29) is sealed by way of circumferential sealing elements (30) at least at the front opening of the ultrasonic horn (12), where the mounting tube (29) is essentially flush with a front extension (17) of the ultrasonic horn (12), and / or wherein preferably the mounting tube (29) is sealed by way of circumferential sealing elements (36, 37) with respect to the housing (13) or, if present, with respect to a backside guiding element (26) or by sealingly quenching the mounting tube (29) at terminal portions thereof.

10. The handgrip according to any of the preceding claims, wherein the housing (13) is provided with at least one venting opening (38), or wherein the housing (13) is sealed and any cavity thereof is filled with inert gas, in particular nitrogen gas.

11. The handgrip according to any of the preceding claims, wherein it comprises a bar shaped element (2a) essentially coaxial with the cylindrical collar (4) as well as, branching off from that bar shaped element (2a) preferably under an angle in the range of 90-60°, a gripping extension (2b) to be held by the user, wherein preferably said gripping extension (2b) is provided with manual actuating elements for controlling the energy transmitted by the cylindrical collar (4).

12. The handgrip according to any of the preceding claims, wherein the guide pin (8) is made of synthetic polymer material, preferably of a thermoplastic material, in particular PTFE and / or PFA, and / or wherein the guide pin (8) has an outer diameter in therange of 1.2-10 mm or 1.5-10 mm, preferably in the range of 2-4 mm, particularly preferably in the range of 2.5-3.5 mm, and wherein diameter of the cannulation (43) is in the range of 0.5-3 mm, preferably in the range of 1-2 mm, particularly preferably in the range of 1.3-1.75 mm, and / or wherein the external diameter of the collar (4) is in the range of 1-80 mm, preferably in the range of 2-10 mm, and in that the external diameter of the guide pin (8) is 0.1 - 20 mm less, preferably 0.1-2 mm or 0.5-1 mm less, and in that the amelioration sleeve has a thickness such that the external diameter thereof is the same as or by not more than 0.2mm or 1.5 mm or 0.01 mm larger or smaller than the external diameter of the collar (4), wherein the amelioration sleeve, at least in some sections, preferably has a wall thickness in the range of 0.1-2 mm or 0.1-1 mm, preferably in the range of 0.2-0.6 mm.

13. The handgrip as claimed in one of the preceding claims, wherein it generates mechanical energy in the form of vibration energy and / or oscillation energy with frequencies in the range of 1 kHz - 10 GHz, preferably in the form of ultrasonic oscillations in the frequency range of 10 kHz - 100 MHz or 20-150 kHz, particularly preferably in the range of 20 - 70 or 20-40 kHz, which are transmitted in the longitudinal, transverse or rotational direction, or in a combination or linear combination of these directions, preferably substantially exclusively in the longitudinal direction, to the collar (4) -and thus — to the amelioration sleeve (7), and / or in that the wire (52) is a preferably sterilized stainless steel pin, preferably having a rounded or sharpened tip at least at one end, with preferably circular cross-section over essentially its full-length, and having a diameter in the range of 0.4-3 mm, preferably in the range of 0.9-1.9 mm, more preferably in the range of 1 .25-1 .7 mm.

14. A method for operating a handgrip as claimed in one of claims 1-13, characterized in that a wire (52) is centrally inserted into a recess (56) and pushed into the very bottom thereof, if needed the inner surface of the recess (56) is prepared for amelioration by using a reamer (6) with a central cannulation, which cannulation is pushed over said wire (52) for controlled insertion of the reamer (6) into the recess (56), the reamer (6) being rotated when positioned I axially advanced in the recess (56) until the desired preparation of the recess (56) is terminated, and subsequently the reamer (6) is taken out while keeping the wire (52) in place, if needed an insertion device (5) having an amelioration sleeve (7) mounted at the distal tip portion thereof and having a central cannulation is pushed with said cannulationover said wire (52) for controlled insertion of the insertion device (5) with the amelioration sleeve (7) into the recess (56) and positioning the amelioration sleeve (7) in the bottom region of the recess (56), and subsequently taking out the insertion device (5) while keeping the amelioration sleeve (7) in the recess (56) and keeping the wire (52) in place, the guide pin (8) is pushed with its cannulation (35) over said wire (52) for controlled insertion of the guide pin (8) and preferably for insertion of the distal portion thereof into the positioned amelioration sleeve (7) in the recess (56) if an insertion device (5) has been used, or for inserting the amelioration sleeve (7) together with or after the guide pin (8), wherein the recess (56) has an internal diameter corresponding substantially to the external diameter of collar (4) and amelioration sleeve (7), until the guide pin (8) abuts against the bottom of the recess (56) and / or engages in a guide taper arranged at the bottom of the recess (56), and then, with simultaneous liquefying of the amelioration sleeve (7) by applied mechanical energy, preferably by applied ultrasound, if needed using a protection sleeve for protecting surrounding soft tissue, and with pushing of the distal end of the collar (4) by manual force application onto the handgrip (2) into the recess (56), liquefied material is introduced into cavities, particularly lateral cavities, adjoining the recess (56).

15. A method according to claim 14, wherein the method is a non-surgical method, and / or, wherein the recess (56) is a recess in an at least partially porous technical material, including wood or wood-like material, or foam material, particularly a polymer foam, a composite foam and / or a metal foam, or in an at least partially dead or living porous human or dead or living animal bone section, particularly in a jaw bone or a spinal column bone, and in that the recess is preferably generated at least partially by preliminary drilling.

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