In traditional joint replacement surgery, bone is prepared to receive a prosthetic implant by first cutting or sculpting the bone with a manual or powered tool such as a saw, drill, or broach which generally exposes the more porous inner cancellous bone. Next, the exposed bone surface is usually cleaned with a sterile saline solution for removal of bone, blood and other tissue debris, and suction is applied to remove the saline fluid and debris. Often, surgical sponges are inserted into a cavity or against the bone surface to absorb excess fluids.
Joint replacements are commonly but not necessarily secured with the aid of “bone cement,” a biocompatible grouting material; a typical bone cement is polymethylmethacrylate (PMMA). The success of such bone cements is thought to depend in part on proper preparation of not only the bone surface, but especially the deeper cancellous “bone bed”.
U.S. Pat. No. 5,037,437 to Matsen III (1991) discloses a significant improvement in the art of preparing bone surface and the deeper bone bed for cemented joint replacement surgery. Matsen identified some of the previously unrecognized shortcomings of traditional liquid flushing lavage for preparation of the cancellous portions of an exposed bone bed. Matsen's invention was based on the finding that dry flowing gas directed at and into the sculpted bony bed effectively prepares the bone for cemented prosthetic implantation by cleaning debris more thoroughly and from deeper in the bone bed. When bone cement is used, the use of gas increases the likelihood of strong mechanical interdigitation of the bone cement with the bone. Matsen also suggests that carbon dioxide gas (CO2) is especially well suited for use as the dry gas for bone preparation, having already been demonstrated safe for use in the human body. Carbon dioxide gas is commonly available in hospital operating rooms, finding decades of use in laparoscopic surgery, for example.
Since the publication of the Matsen patent, tools have become available for preparing bony surfaces using sterile, dry gas or sterile admixtures of gas and liquid. A CO2 bone preparation system is available, for example, from Kinamed, Inc. in Camarillo, Calif. (marketed under the trade name “CarboJet”). However, certain essential components of this system must be sterilized prior to each use. The sterilization procedure is typically performed at a location remote from the operating room, which is necessarily costly and time-consuming.
A disposable CO2 bone preparation system is described. Certain essential system components (including tube set, hand piece, and nozzle) that are necessary to perform dry gas bone preparation are provided in a single package. No assembly or sterilization of these components need be performed by the user; the system is ready to use once the package is opened and the tube set is coupled to a regulated, medical grade CO2 source.
Features of the present system include:
Referring to
As best seen in
As best seen in
Body 11a may be formed from plastic, such as thermoplastic polymer, as noted below, and is molded into its desired shaped, optionally, in two halves, which are then joined together by welding or fasteners, such as rivets or screws, or may be bonded together such as with an adhesive. Nozzle 12 may too be formed from plastic or metal.
Trigger 28 is a wedged-shaped member (also optionally molded from plastic) that is pivotally mounted at one corner thereof to body 11a by a pivot member 28a (
In the illustrated embodiment, as best seen in
Optionally, as best seen in
Alternately, tube set 14 may connect to hand piece 11 at port 18a via a bayonette style fitting (such as shown in reference to hand piece 211 in
In use, a user grips the hand piece 11, places the tip of the nozzle 12 near an area of bone to be prepared, and compresses trigger 28 to start the flow of gas, which also as noted may allow modulation of the flow of gas between a non-flow state and a full flow state. Additional control over the direction of the gas flow is preferably provided by making nozzle 12 rotatable around its longitudinal axis, which may help achieve a better angle with which to clean a particular bone surface, and/or by the style of the nozzle tip 54.
In the illustrated embodiment of
To facilitate rotation of nozzle 12 around its longitudinal axis, nozzle 12 may include an enlarged collar 30 in
As noted above, hand piece 11 and nozzle 12 (and trigger 28) may be made from a plastic, such as thermoplastic polymer, such as ABS. The use of a plastic for the hand piece and nozzle is advantageous, as the material's low thermal conductivity helps insulate the user's hand from the low temperature of the flowing, pressurized CO2 gas, and its light weight helps reduce user fatigue that might otherwise occur. Further, as noted above, the hand piece may be formed from two pieces, which are joined together, and further may be formed from two hollow pieces, with the internal passageway and other mounting structures discussed below being formed by internal ribs and walls so that the weight of the hand piece can be further reduced.
The sterilization process, for example, a gamma sterilization process, tends to degrade certain plastics. While some plastics are “gamma stable” and degrade so slowly as to not be noticeable, others degrade faster. As such, the rate at which the selected plastic degrades will affect the system's functional shelf life.
The tubing portion included as tube set 14 is also formed from a plastic, and typically a more flexible plastic, such as polyvinyl chloride (PVC). Referring back to
The materials with which the fittings are made can also affect the system's functional shelf life, as they will also be subjected to the sterilization process. Suitable fitting types includes barbed with crimp, barbed with ferrule, and pocket with glue, with barbed with ferrule typically preferred. It would also be possible to use only barbed connections, though this may require an alternate type of tubing.
An optional feature that may be provided as part of the present disposable CO2 bone cleaning system or as a stand-alone device for use with reusable bone cleaning systems is a shield, which can be configured to prevent the splash or spray of fluid and debris, and may be configured to snap onto the system's nozzle, which are more fully described below.
Referring back to
The hand piece may also include a U-shaped channel 94 on the topside of hand piece 11 above grip 11b, which is configured to provide a frictional grip of tubing inserted therein, which may be used, for example, to provide suction as discussed in connection with
Referring to
As best seen in
Shield 50 also includes a plate 56 that extends from base 52, which is curved or non-planar so that it straddles nozzle tip 54 and forms deflecting surfaces on either side of nozzle tip 54. The opposed edges of plate 56 are continuous with the opposed edges 58 of collar 52a to better wrap around nozzle tip 54, but is generally triangular in shape as seen in
The splash shield is optionally configured so that it is retractable along nozzle 12, such that it is capable of being slid up the longitudinal axis of the nozzle toward the hand piece. In this manner, when the shield is either not needed or when additional visibility or physical access to a particular area is desired, a user may simply move the shield up along the nozzle's longitudinal axis rather than remove it. This can be facilitated through the selection of the material, e.g. low friction material to allow the shield to slide and/or by the spring force exerted by the shield on the nozzle, which is designed to provide the snap fit coupling but a coupling that is loose enough to allow the shield to slide. Optionally, as described in reference to hand piece 211, additional structures may be formed on the nozzle to prevent it from sliding too far or to define a discrete position or discrete retracted positions for the shield along the nozzle. The splash shield can have any of a number of shapes—those illustrated herein are merely examples.
Referring to
In the illustrated embodiment, rather than having a straight cylinder collar, like collar 52a, collar 62a may have a curved outer surface or recesses 62b to provide a tactile surface for easier handling of shield 60. Edges 68 may also be tapered on one or both sides to form a cam surface or cam surfaces to facilitate spreading of the collar when pressed again the nozzle.
Shield 60 also includes a plate 66 that extends from base 62, which is also curved or non-planar so that it straddles nozzle tip 54 and forms deflecting surfaces on either side of nozzle tip 54. Plate 66 may have a more curved configuration with a fluted portion of region on the opposed sides plate, which are on either side of nozzle tip 54. Further, they may be located at the transition with collar 62a, and only partially extend around the collar to have a more open design to increase user visibility of the nozzle tip. In other words, the opposed edges of plate 66 are not contiguous with the opposed edges 68 of collar 62a and instead are offset around collar 62a from edges 68.
Referring to
Shield 70 may be configured to provide suction at the distal end of the nozzle, to capture and remove fluids and debris dislodged by the flowing gas. Referring to
In another embodiment (
Channel 88 includes a port 88a in the form of a cylindrical tube that is in fluid communication with internal passageway 88b of channel 88, which may include a cannulated barb 88c for connection with suction tubing to also form a suction line. Here, the vacuum pressure from the suction line is directed by channel 88 to the distal end 86a of the splash shield 80 or plate 86 to effectively remove fluids contained by the shield. While illustrated as provided on the outer surface of shield 80, channel 88 may be internally formed in plate 86 and base 82 so that it maintains the same outer surface topography as shield 60, or it may be formed on in the inside surface of base 82 and/or plate 86.
Referring to
In the illustrated embodiment, as best seen in
Further, nozzle 112 includes an adjustment collar 130 that includes a plurality of recesses 130a to form a tactile feedback feature that allows a user to rotate the nozzle as desired about its longitudinal axis.
In the illustrated embodiment, nozzle 112 includes a nozzle tip 154 is configured for long bone preparation and is formed by the terminal end (cut at ninety degrees to the longitudinal axis of nozzle 112). Although not formed with ribs or indentations, handgrip 111b may be formed from a high friction material to improve the grip of a user.
In another embodiment, hand piece 211 (
Referring to
In the illustrated embodiment, shield 260 is of similar constriction to shield 60 and includes a base 262 and a curved extended plate 266 that extends from base 262. Base 262 also is formed by a bifurcated collar 262a whose slit 262b is sized so that its opposed edges 268 are spaced so that they must be separated to allow shield 260 to be mounted on nozzle 212. When mounted, opposed edges 268 rest on ribs 212a. In the illustrated embodiment, collar 262a includes a notch on its opposed sides, which matches the angled portions 212d of ribs 212a so that when mounted to nozzle 212, base 262 will either form a snap coupling with nozzle 212 and/or fit tightly in the space defined by the ribs and stop on nozzle 212.
To facilitate placement or removal of shield 260, base 262 optionally includes a projecting flange 270, which may include recesses on its opposed sides to form tactile surfaces on the either side of flange 270 to further enhance a user's grip of and ability to place shield 260. Additionally, base 262 may include a visual indication 272, such as a triangle, which a user can use to align with the stop 212b, which may be in the form of an arrow, to assure proper alignment of the shield 260 on nozzle 212.
Referring now to
Carrier 215a may be formed from a sheet of plastic with a plurality of couplers arranged in a plane. Each coupler may be formed from cuts outs 215b in the sheet that can be folded over and interconnected to form loops 215c around the components. Other cutouts may simply fold upwards with slots 215d to allow a component, such as a shield, to be held by simply being inserted into the slot. In this manner, when removed from the pouch, the various components will remain supported on the carrier and, further, allow the components to be disconnected in a sequence that reduces the chance of contamination.
For example, the end of the tube set may first be removed and connected to the CO2 supply, and then the tubing may be unwound, with the hand piece then removed followed by the shield, which can then be mounted to the nozzle.
Referring to
As best seen in
The internal configuration of any of the disposable hand pieces described above may have several additional optional features, as described below and illustrated in
As noted above, trigger 228 controls the flow of fluid through internal passageway 211c of hand piece body 211a. To that end, trigger 228 supports a valve stem 286, which is mounted in a passageway 211f along valve axis 286a, which intersects with passageway 211c. In this manner, as valve stem 286 moves along valve axis 286a in passageway 211f, the internal passageway 211c of hand piece 211 will open or close to allow fluid to flow though hand piece 211. The amount of flow will, therefore, be controlled and modulated by the position of the valve stem 286 in passageway 211f, as controlled by trigger 228.
As best seen in
Optionally, as best seen in
Similar to hand piece 11, hand piece 211 may also include a U-shaped channel 294 on the topside of hand piece 211 above grip 211b, which is configured to provide a frictional grip of additional tubing 16 or tube 16a inserted therein, which may be used, for example, to provide suction or which forms of a light pipe to project light on to the bone being prepared. Channel 294 may be formed when molding body 211a. Again, ribs and/or a resilient or elastomeric material may be molded on the inside of channel 294 to increase the friction forces on tubing inserted therein.
In any of the above embodiments (as well as variations thereof), the nozzle tips of the various hand pieces may be varied and, further, configured to clean or dry trunnions on implants. Many orthopedic implants utilize a trunnion to connect mating, modular components to them. A trunnion is a carefully engineered truncated cone feature on the implant that provides a place to mate the modular component, which has a matching conically tapered trunnion receptacle portion. The surfaces of these trunnion features must be precisely shaped and machined to very close tolerances to ensure a very precise fit so that micro motion between the two parts joined by the trunnion is minimized. These modular components in orthopedic implants typically experience very high cyclic loads, making the surfaces that are joined by the trunnion susceptible to fretting wear and other forms of corrosion. Wear and corrosion due to this micro motion has been shown to liberate metal debris that can be very damaging and toxic to both nearby and remote tissues in the patient. Therefore, in addition to having available carefully designed and machined trunnion components to implant, the surgeon must ensure that, during the surgical procedure, the trunnion surfaces are as clean as possible before assembly of the modular components so that their precise interfit is not compromised in any way. The implant that incorporates the male portion of the trunnion joint is typically implanted first and is left exposed to blood and other tissue debris during the procedure. The modular component that incorporates the female portion of the trunnion connection is typically opened from its package and immediately applied to the male portion so is therefore less exposed to contamination in the surgical field.
The present bone preparation systems would preferably be offered in several different configurations or ‘kits’, each intended for a specific application. For example, one kit might be intended for use during knee replacement surgery, and another for use during hip or shoulder replacement surgery. The nozzle designs are preferably optimized for each of these applications and would thus be different, resulting in different kit configurations. Accordingly, any of the above hand pieces may be fitted with a nozzle tip that is configured to prepare the male portion of a trunnion.
Referring to
Compressed sterile CO2 gas can, therefore, be introduced through inlet port 302 from the respective hand piece onto a trunnion 310 located in cone-shaped chamber or space 300c formed by cone-shaped body 300. As described more fully below, nozzle tip 354 is configured to direct the gas downwardly onto the trunnion 310.
In the illustrated embodiment, cone-shaped body 300 includes an inner conical wall 300a and an outer conical wall 300b to define an inner space there between that forms into which gas flow is directed from inlet port 302. Body 300 may be molded as a one piece member from a single material or molded as a one piece from multiple materials, such as by co-injection molding, or may be assembled from multiple pieces (e.g. each molded) and joined together, for example by fasteners or welding. Therefore, at least the inner wall may be formed from a non-metallic material, such as plastic.
Inner conical wall 300a forms cone-shaped chamber or space 300c (with a central cone axis) that is sized to form fit over and receive trunnion 310 therein and, further, forms a space there between to allow the CO2 gas to flow over the trunnion, and also allow the CO2 gas stream to impact the trunnion surface at a desired angle. To that end, inner conical wall 300a includes a plurality of passageways 304 that form apertures or openings 304a, which are arranged optionally in a uniform spacing along wall 300a (both vertically and horizontally). Passageways 304 are optionally angled downwardly to form an acute angle relative to the central cone axis so that when CO2 flows from the openings 304a, the gas will be directed downwardly onto the trunnion 310. The number and size and shaped of openings may vary. In the illustrated embodiment, the passageways are be circular in cross-section in wall 300a but form oblique openings 304 at inner wall surface 300c. The shape of the openings 304 may be varied, however, as noted.
Openings 304a, therefore, can generate vectors 306 of compressed CO2 being directed distally (towards the trunnion) to push fluid away or down along and away from the trunnion. Additional openings 308 may also be located in the base rim of cone-shaped body 300 in a base wall 300d, which connects the inner and outer walls 300a and 300b together. CO2 flowing through these openings can clean an exposed bone surface. Cone-shaped body 300 may be designed to mate with, for example, a femoral stem trunnion 310, which should be kept clean to prevent mechanically assisted crevice corrosion (MACC) and subsequent adverse local tissue reaction (ALTR).
As shown in
In the illustrated embodiment, similar to nozzle tip 354, nozzle tip 454 is formed from a conical-shaped body with an inner wall 400a and an outer wall 400b, which define there between a space into which the gas is flowed from inlet port 402 (which is coupled to a supply tube 402a that connects to a gas supply) and directed onto the trunnion 410 (positioned therein) positioned in chamber 400c via passageways 404. Similarly, body 400 may be formed from a non-metallic material, such as plastic, so as to prevent possible scratching or damage of the trunnion during use, and may be molded as a one piece member from a single material or molded as a one piece from multiple materials, such as by co-injection molding, or may be assembled from multiple pieces (e.g. each molded) and joined together, for example by fasteners or welding.
In this embodiment, as noted, passageways 404 are angled upwardly so that opening 404a are also oblique but direct the flow of gas upwardly onto a trunnion positioned in nozzle tip 454.
For example, nozzle tip 454 may be configured to cover or mate with, for example, a femoral stem trunnion 410, which should be kept clean to prevent MACC and subsequent ALTR. An alternate configuration can place the suction connection at the top of the trunnion cleaner (offset from the compressed gas inlet) so that suction flow is in alignment with the direction the fluid and debris is being blown. With both versions, the gas could be directed via small holes (as depicted) or via a semi-circumferential angled slot at the base of the cone (not depicted).
Referring to
Body 500 includes an inner wall 500a and an outer wall 500b, which define there between a space into which the gas is flowed from inlet port 502 (supply tube not shown) and directed onto the trunnion (positioned therein) positioned in chamber 500c via passageways 504. The gas and debris are then directed to an outlet 522, provided in the form of a collection cup 522a, similar to the previous embodiment.
In this embodiment the passageways 504 are arranged in a single row around and adjacent the base opening of body 500, to create an “air knife” (focused pressure gradient) that is directed upwards along the surface of the trunnion, to urge the fluidic debris upwards toward the vacuum collection point at outlet 522. Similar to passageways 404, passageways 504 are angled upwardly so that opening 504a are also oblique but direct the flow of gas upwardly. For further details of the collection cup and tubing that directs the gas and liberated debris away from the trunnion and to discharge tube or the like reference is made to the above embodiment.
Referring to
In the illustrated embodiment, body 600 directs gas onto the trunnion (positioned in chamber 600c) via one or more annular passageways 604, which may also generate an “air knife”.
As best seen in
In the illustrated embodiment, as best seen in
Thus passageway 604 also creates an “air knife” (focused pressure gradient) that is directed upwards along the surface of the trunnion positioned in chamber 600c (even when perpendicular the air knife may be directed upwardly depending on the shape of the trunnion) to urge the gas and fluidic debris upwards toward the vacuum collection point at port 622. With the high pressure gas flowing into inlet 602, high pressure gas jets, labeled as arrows A (
Optionally, as noted, collection cup 622a may be spaced from outlet 622 to form one or more vents so that the debris and gases exiting from the top of the device could pass towards low pressure atmosphere. With compressed air vacuums, the gas and debris flow typically go into a fabric bag that captures the debris and allows the gas to escape to atmosphere. In this manner, the gas flow changes direction and heavier substances fall out on the bend and collide with a collecting surface. In this embodiment, the change of direction of the gas is the labeled with arrow C, and the heavier substances are designated using arrows D. Thus, the active suction line is attached to the collection cup 622a at the center of body 600 and includes a collecting surface 622c, which can straddle the opening at outlet 622 to capture and remove the collected fluid debris as it occurs.
Optionally, collection cup 622a may be attached to body 600, but, as noted, at a spacing or distance to thereby form one or more vents, which allows the overall gas flow to vent efficiently through a circumferential gap between the cup and body 600, and capturing the debris to be evacuated by the suction tube instead of requiring the use of sponges or towels. Alternatively, possibly a filter bag could be employed as previously mentioned.
While some of the nozzle tips for cleaning trunnions are shown absent the nozzles or hand pieces, it should be understood that they could also be included as part of the system, like the other nozzle tips shown herein. Further, while several of the nozzle tips are described in the context of use with trunnions, these nozzle tips may also be used on other tapered or cylindrical shaped object to be cleaned. Additionally, features described in reference to one tip may be incorporated into the other tips describe herein. Therefore, the use of the term “embodiment” is for convenience only and not intended to limit the scope of the claims.
Although not specifically mentioned for each of the above components, any of the hand pieces and their respective components parts (and accessories) may be made from plastic or metal or both. Though as noted, in some instances a plastic construction may be more suitable, for example, to reduce scratching or damage of the bone or the trunnion. Further, the hand pieces and their respective components parts (and accessories) may be molded, such as by injection molding, including co-injection molding, or cast molding or 3D printed or the like. They may be formed as a one-piece (unitary) construction or from multiple pieces that are then assembled together.
When using any of the nozzle tips, a disposable (surgical drape or similar) or reusable (silicone or similar) sleeve 530 may be used. Referring to
A potential method or workflow would be: The trunnion is cleaned of gross debris (wiped or similar); the sleeve is inserted; the trunnion is given a final cleaning; the prosthetic head is mated to the trunnion; finally, the sleeve is removed.
While several forms of the hand piece, nozzle, tip, shield, and packaging have been shown and described, other forms will now be apparent to those skilled in the art. For example, one or more of the features of one hand piece may be incorporated into the other hand pieces descried herein. Similarly, one or more of the features of one tip may be incorporated into the other tips described herein. In addition, one or more of the features of one shield may be incorporated into the other shields described herein, and one or more of the features of one packaging or packaging arrangement may be incorporated into the other packaging or packaging arrangements described herein. As noted above, the use of the term “embodiment” is used for convenience to refer to the illustrated combinations and not intended to limit the scope of the invention.
This application claims the benefit of Prov. Appl. Ser. No. 63/046,357, filed Jun. 30, 2020, entitled BONE PREPARATION SYSTEM, which is commonly assigned to Kinamed, LLC and which is incorporated by reference in its entirety herein.
Number | Date | Country | |
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63046357 | Jun 2020 | US |