Method and device for reducing implant contamination from handling

An orthopedic implant has a removable handling cover coupled thereto which includes a thin-walled layer extending over a grasping portion of the outer surface. An outer container can sealingly house the orthopedic implant within a sterile environment and support the orthopedic implant in an orientation that presents the handling cover for grasping. A surgeon can manually grasp, handle and manipulate the implant into an implantation position, and remove the handling cover from the implant during implant surgery, and without the need to directly contact any surface of the orthopedic implant itself. Related methods of providing such an implant assembly and of reducing infection from contamination during implantation surgery are also disclosed.

FIELD

The present disclosure relates to methods and devices for reducing implant contamination from handling.

BACKGROUND

Infection remains a devastating complication of total joint replacement, affecting about one to four percent, of all primary procedures. Infection can occur by contamination at the surgical site at the time of the procedure or by hematogenous seeding. Possible routes for contamination at the time of surgery include the surgical team touching the implant or tissues within the operative site with contaminated gloved hands or instruments. Instruments can become contaminated because the cleaning procedures were not adequate after prior use or because the instruments were contaminated during the current surgery.

In a recent study, Davis showed that 63 percent of primary hip and knee arthroplasties had contamination in the field of operation (Davis 1999). Davis' study also showed that about 29 percent of gloves used in the primary hip and knee procedures for preparation were found to be contaminated. In another study, Maathuis showed that 30 percent of broaches used in total hip arthroplasty had bacterial contamination at the end of the procedure (Maathuis 2005).

One significant source of such contamination is when packages containing sterile implantable devices are opened in the operating room, it is almost always necessary to manually remove the implant from the packaging. In many cases, removal of the implant from the package requires handling of the implant with potentially contaminated gloves or implements, which can transfer contamination to the surface of the implant.

SUMMARY

Disclosed is an orthopedic implant assembly providing reduced contamination from handling that can include an orthopedic implant having an outer surface including a grasping portion and a bone-facing portion. A removable handling cover is coupled to the orthopedic implant and includes a thin-walled layer extending over the grasping portion of the outer surface. An outer container can sealingly house the orthopedic implant within a sterile environment and support the orthopedic implant in an orientation that presents the handling cover for grasping upon opening the outer container. The removable handling cover can provide a removable grasping portion for manually grasping, handling and manipulating the implant into an implantation position with the bone-facing surface facing an adjacent bone during implant surgery without the need to directly contact any of the outer surface of the orthopedic implant. And the removable handling cover can be removable during surgery after the implant is moved into the implantation position.

Also disclosed is a method of providing an orthopedic implant with reduced contamination from handling. The method can include covering a grasping portion of the orthopedic implant with a handling cover comprising a thin-walled, protective layer that is removable from the implant during implantation surgery. The method can also include supporting the orthopedic implant in an orientation within a container that presents the removable, thin-walled, protective layer to a user upon opening the container, and sealing the orthopedic implant in a sterile condition within a sterile environment of a container.

A method of reducing infection from contamination of an orthopedic implant during surgery is additionally disclosed. The method can include opening a sterile container housing the orthopedic implant to present a removable thin-walled layer selectively covering a handling portion of the implant for easy grasping. The method can additionally include handling and manipulating the implant into an implantation position by manually grasping the presented removable thin-walled layer, and removing the removable thin-walled layer prior to closure during the implantation procedure.

DETAILED DESCRIPTION

FIGS. 1-4illustrate various orthopedic knee implant components that can be used together, each including a handling or grasping cover. Specifically,FIG. 1illustrates a femoral component10of the orthopedic knee implant. The handling cover12of the femoral component10comprises a compliant film that covers a grasping portion14of the outwardly facing surface of the femoral component10.

In this embodiment, the grasping cover12film extends over the grasping portion14, which is at least a portion of the non-bone facing surface, including the sides of the femoral component10. Thus, a surgeon can readily grasp, manipulate and place the femoral component10into an implantation position with the bone facing surface16adjacent the femoral bone while the surgeon only directly contacts or touches the grasping cover12. In other words, there is no need to directly contact any portion of any surface14or16of the femoral component10during implantation surgery.

A posteriorly-facing portion13of the outer surface14of the femoral component10, above dotted line18for example, can lack any handling cover12film. Alternatively, a secondary portion20of the handling cover12film above dotted line18can be separately removed prior to positioning the femoral component10in an implantation position. After the femoral component10is in position, the remainder, or primary portion of the handling cover12film can be removed from the grasping surface14of the femoral component12.

The handling cover12film can include a tab22which the surgeon can grasp to aid removal of the film12. The handling cover12film can comprise a thin film coated with adhesive to adhere to the grasping surface14of the femoral component10. The handling cover film can comprise a naturally adhering film, for example, held in place with static electricity. The adhered handling cover12film can also comprise a shrink wrap film. Other mechanisms can be used to adhere a handling cover12film to the implant. For example, an elasticized member34at an opening of a thin film member26′ (similar to a shower cap) can be used as illustrated inFIG. 3.

The handling cover12film can be formed directly on the implant component. For example, the grasping portion of the femoral component10can be coated with a material that forms a film on the surface and that is removable during implantation surgery as described herein. For example, the coating material can be printed or painted on the grasping surface14of the femoral component10of the implant to form the handling cover12film.

FIG. 2illustrates a tibial component24that can be used with the orthopedic knee implant ofFIG. 1. Similar to the discussion above, the tibial component24includes a thin-walled handling cover26film over a grasping surface28. In this embodiment, the grasping surface28includes the upwardly facing tibial tray and sides. Here too, there is no handling cover26on the bone facing surface30of the tibial component24, allowing the tibial component24to be grasped and manipulated into an implantation position adjacent the bone without the surgeon needing to directly contact any portion of the tibial component24. The handling cover26film can be removed from the tibial component24after it has been moved into an implantation position.

As appropriate, cement can be applied to a bone opposing surface30of an implant component, including tibial component24. The surgeon can grasp and manipulate the tibial implant component24using the handling cover26film. The handling cover26film can also help insure bone cement does not remain on the tibial component24in undesired locations. For example, any cement extending onto the handling cover26film, can be removed along with removal of the handling cover26film.

FIG. 4illustrates a polyethylene component46that can be used with the orthopedic knee implant components ofFIGS. 1 and 2 or 3. The polyethylene component46, includes a handling cover48. After the handling cover48film has been removed from the tibial component24, the polyethylene component46can be coupled to the upper surface or tibial tray thereof, opposing the femoral component10.

The grasping portion47and corresponding handling cover48film can include only a portion of the sides thereof. For example, the handling cover48film can cover the sides and a few millimeters of the top, bottom, or both. In addition, the handling cover48can end at edges50so that a posterior portion of the sides of the polyethylene component46is left uncovered. In the illustrated embodiment, the handling cover48can extend around approximately 270 degrees of the anterior portion of the side wall. In other words, leaving about 45 degrees on either side of the posterior midpoint of the side wall uncovered by the handling cover48.

In addition, a separate handling cover film (not shown, but similar to20ofFIG. 1) can be provided over the upper surface of the polyethylene component46. Thus, the separate handling cover film can provide additional protection, and removed prior to positioning the polyethylene component46into an implantation position.

The polyethylene component46can be grasped and manipulated into an implantation position via the handling cover48film and without the surgeon needing to directly contact with any portion of the polyethylene component46. A surgeon can grasp extending tabs53to peel the handling cover48film from the polyethylene component46after it is in an implantation position. Extending or grasping tabs53can be provided as an extension of the film member itself as illustrated, or as an extending string member (not shown), or as another extending or grasping tab member.

FIGS. 5-8illustrates various orthopedic hip implant components.FIG. 5illustrates a femoral stem component54of the orthopedic hip implant. A grasping portion56can include the trunnion59, shoulder region60and neck therebetween. The grasping portion56is covered by a handling cover58film. In contrast, the bone facing or opposing portion61of the stem component54might not include a handling cover58, or can have a handling cover (not shown) that can be removed prior to manipulating the femoral stem component54into an implantation position adjacent the bone by grasping the handling cover58film and without directly contacting any surface of the femoral stem component54.

The handling cover58of this embodiment includes a frangible tear line or cut-through line providing a separation line identified by dotted line62. For example, a surgeon can grasp pulls the extending grasping tabs64to remove the handling cover58film in portions along separation line indicated by dotted line62. Thus, the surgeon can peel two halves of the handling cover film58from the femoral stem component54without directly contacting the femoral stem component54.

FIG. 6illustrates a modular femoral head component66for use with the femoral stem component54ofFIG. 5. The thin-walled handling cover68film can overlay essentially all of the outer polished surface or grasping portion67of the femoral modular head component66. In this case a grasping tab69is illustrated. Any of the previously described grasping tabs (FIGS. 1 and 2), frangible tear lines (FIGS. 3 and 5), strings (FIG. 4lifting string andFIG. 5tear string), or combinations thereof, however, can be used. In addition, the thin-walled handling cover68can include a plurality of any of the above.

Not only can the handling cover68enable a surgeon to manipulate the femoral head component66into an implantation position, but the cover68can remain on the surface of the femoral head component66corresponding to the grasping surface56while an impact tool is used to seat the femoral head component66onto the stem component54. In this way, not only is the risk of contamination reduced from direct manual contact by a surgeon's hands, but also from direct contact with an impaction tool (not shown) during the implantation surgery.

FIGS. 7 and 8illustrate an acetabular cup component70and an acetabular liner component72of the hip implant ofFIG. 5. A handling cover74film can be provided over the upper surface76of the acetabular cup component70, including the locking protrusions78, and the interior spherical concave surface80. The handling cover74film can include cylindrical openings surrounding each of the screw apertures82on the interior surface80of the cup70(simply indicated by dotted lines75). In this way, the acetabular component70can be grasped and manipulated into an implant position, with the porous outer bone-facing or opposing surface85adjacent bone, by contacting only the grasping surface84covered by the handling cover74film. Screws (not shown) can also be inserted through the apertures82to fix the acetabular component70in place in a full and final implantation position. Thereafter, the handling cover74can be removed.

After the handling cover74has been removed from the acetabular component70, the surgeon can grasp and manipulate the acetabular liner component72into place within the concavity of the acetabular component70. Similar to the acetabular component70, liner72can include a handling cover86film over the upper surface88, including the radial outer side surfaces of locking protrusions90. In this example, the handling cover86is stretched between opposite portions of the upper surface88to form a generally planar film above the interior spherical concave surface92. The handling cover86film can be absent from the radial outer sides forming locking recesses94to enable the acetabular liner72to be fully seated within the cup70prior to removing the handling cover86film during implantation surgery.

Here too, any of the previously described grasping tabs (FIGS. 1 and 2), frangible tear lines (FIGS. 3 and 5), strings (FIG. 4lifting string andFIG. 5tear string), or combinations thereof can form part of the thin-walled handling covers74and86or be provided in addition to the handling covers74and86. In addition, the thin-walled handling covers74and86can each include a plurality of any of the above.

While each ofFIGS. 1-8illustrate thin-walled grasping covers that all comprise flexible, compliant, or conformable films,FIGS. 9-11illustrate grasping covers that all comprise thin-walled molded members. It is further noted that each of the embodiments ofFIGS. 1-8can be housed within a sterile environment of a container as specifically illustrated inFIGS. 9-11.

FIGS. 9 and 9Aillustrate a molded thin-walled handling cover100for a femoral knee implant component102. The combined assembly100and102is supported within a sterile container104to present the thin-walled molded handling cover100to a surgeon upon opening the top cover106of the container. Thus, the surgeon can readily grasp and remove the femoral component102and handle and manipulate it into an implantation position by grasping the handling cover100over the grasping surface portion107of the femoral component102without directly touching any surface of the actual implant.

The handling cover100includes a pair of protrusions108on inner surfaces that engage against lower edges110on each side of the femoral component102. Thus, after the surgeon is done manipulating the femoral component102, pressure can be applied by the surgeon along edges114to release the protrusions108from the edges110; facilitating removal of the handling cover100from the femoral component102.

FIG. 10illustrates a tibial knee implant component116which can be used with the component ofFIG. 9, and includes a molded thin-walled handling cover118, in a sterile package120. Similar to the above, the sterile package120supports the tibial component116in an orientation that presents the grasping surface122covered by the handling cover118to the surgeon upon opening the package120.

The handling cover118can include one or more discrete projections or edges124that engage an edge126of the tibial component116. Similar to edge114ofFIGS. 9 and 9A, the handling cover118can include a flared portion or tab128or can including an edge that can be pushed to release the handling cover projections124from the edge126of the tibial component116; facilitating removal of the handling cover118.

FIG. 14illustrates a polyethylene knee implant component160that can be used with the knee implant components ofFIGS. 9 and 10. A molded thin-walled handling cover162is formed to extend over a portion of the side wall defining a grasping surface166. The handling cover162can also extend along a periphery of the upper surface indicated by dotted line168to help minimize any direct contact with the surface of the polyethylene component160during, grasping, handling, and manipulation thereof. The handling cover162can be molded as a spring-like member which grasps the sides166of the polyethylene component160, but can also be readily removed during implantation surgery after it has been placed in an implantation position. For example, a surgeon can simply grasp tab170and pull in the direction indicated by arrow A, causing spring-like handling cover162to be removed from the polyethylene component160.

FIGS. 11, 11A, and 11Billustrate a femoral stem component130of a hip implant, including a handling cover132. The femoral stem component130is supported in a sterile package134to present the grasping surface136covered by the handling cover132to the surgeon upon opening the container134similar to that described above. The handling cover132is molded with protrusions133to engage the undercut138provided by the flats140of the neck142of the femoral stem component130.

As best seen inFIG. 11B, the handling cover132has an oval cross-sectional shape and is molded from a resilient material. Thus, a surgeon can squeeze along the major axis as indicated by arrows A of the oval cross sectional shape of the handling cover132; causing expansion along the minor axis as indicated by arrows B to allow the protrusions133to move past the projection or edge resulting from the undercut138creating the flats140. In this way, a surgeon can release and remove the handling cover132from the femoral stem component130after it has been manipulated into an implantation position within the body.

FIG. 12illustrates a femoral head component146of the hip implant ofFIG. 11within a sterile package147supported in an orientation to present the grasping surface148covered by a molded thin-walled handling cover150to the surgeon upon opening the package147.

The handling cover150can be molded to closely fit the polished outer surface148so it is coupled to the head146as a result of the reduced diameter adjacent the base152of the head146. Handling cover150can include a plurality of split lines indicated by dashed line154. For example, two, four, six, or some other number of equally spaced split lines154can extend partially up from the bottom edge toward the midpoint of the handling cover150. Thus, the split lines154can separate and allow the molded handling cover150to be removed from the head146.

FIG. 13illustrates an alternative tibial component178, handling cover180, and sterile container182. In this example, the handling cover180is a molded thin-walled member coupled to the tibial component178via a protrusion184engaging against the edge186of the implant178. Although a single blister container is illustrated, the sterile container of this or any other embodiment can comprise two or more nested blisters to provide increased assurance of sterility.

FIG. 15illustrates a femoral component172for a knee implant including a thin-walled handling cover174with an extending grasping handle176. As with the packages and the other features associated with the thin-walled handling covers described herein, such a grasping handle176extending from the thin-walled portion of the handling cover174can be provided with any of the embodiments described herein, and can be integrally molded with the molded embodiments.

Any of the thin film covers described herein can have a visual appearance that makes it immediately apparent that the thin film cover has not been removed from the implant. For example, the thin film cover can comprise a bright color, a printed pattern, or both, causing the thin film cover to visibly stand out against the implant.

It should further be understood from the above that several orthopedic implant components can be implanted together during a single implantation surgery, and that each one of the components implanted together can be provided as part of an assembly with a thin-walled handling cover, an outer package providing a sterile enclosure, or both.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. For example, although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as “first,” “second,” and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.

The term “implantation position” can encompass the full and final implantation position of the implant within the body, but is not limited to such. Thus, the term “implantation position” can include other positions, such as where a bone opposing surface of an implant is positioned adjacent a corresponding bone, e.g., in a position near the full and final implantation position.