The present disclosure relates to a spacer mold, and more particularly, to a modular articulating two-stage cement hip spacer mold.
A natural joint may undergo degenerative changes due to a variety of etiologies. When these degenerative changes become so far advanced and irreversible, it may ultimately become necessary to replace the natural joint with a joint prosthesis. However, due to any number of reasons, a small portion of patients that undergo such orthopedic surgical procedures may suffer from infections at the surgical site and generally around the implanted joint prosthesis. In order to cure such an infection in a two-stage re-implantation, the implanted joint prosthesis may be removed, the site is thoroughly debrided and washed, antibiotics are applied to the infected site via a temporary implant until the infection is eliminated, and a new revision type joint prosthesis is then implanted during a subsequent orthopedic surgical procedure.
Accordingly, there is a need for apparatus and methods to facilitate two-stage re-implantation which expedite healing at the site, provide a better fitting implant, reduce the amount of time a patient is bedridden, increase the efficiency of the surgical procedure while reducing the surgical time and cost, eliminate any re-cleaning or re-sterilizing steps, and create a customizable procedure.
This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features.
In various embodiments a modular articulating cement spacer mold for forming a temporary implant is provided. The modular articulating cement spacer mold comprises a first mold, a second mold, and a connecting hinge. In various embodiments, the modular articulating cement spacer mold can include a self-cleaning mechanism, a self-securing device, or a ventilation forming feature.
Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.
The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.
Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings.
Example embodiments will now be described more fully with reference to the accompanying drawings.
The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. Although certain examples and surgical methods disclosed herein are in conjunction with a temporary hip implant, it is understood that the molds and surgical methods disclosed herein can be used in any orthopedic revision surgery for any area in the patient.
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.
Spatially relative terms, such as “inner,” “outer,” “beneath”, “below”, “lower”, “above”, “upper” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. Spatially relative terms may be intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the example term “below” can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.
Referring to
The molds 100 and 200 can be formed from any biocompatible material including various polymers. In various embodiments, the polymeric material can be sufficiently rigid to provide structure to the resultant implant components 300 and 400 as shown in
Turning to
Referring to FIGS. 1 and 2A-2B, the head component first mold portion 102 includes an outer surface 120, an inner surface 122, and connection components 124a which further defines a series of openings 126a therein to accommodate a connection component pin 128 (only shown in
Returning to FIGS. 1 and 2A-2B, on the end of the edge 130 which is opposite to the end having the connection component 124b, the head component first mold portion 102 defines an opening 134a to accommodate a screw 136 to secure the head component first mold portion 102 with the head component second mold portion 104. As best shown in
In an exemplary use, advancing the screw 136 into the opening 134a and securing with the threads 134b secures the first mold portion 102 and second mold portion 104 together. This securement can be further supported by forming a fold-over region 137 over a portion of the screw 136. By fixing the ledge 135 over the screw 136 to form a fold-over region 137, the operator is provided a bearing surface against which the screw 136 cannot advance. When the operator rotates the screw 136 as to back it out from the threaded opening 134b, the ledge 135 and fold-over region 137 trap the screw 136, prevent the backward rotation of the screw 136 from removing the screw 136, and instead help pry apart the first mold portion 102 and second mold portion 104.
With reference to
Returning to
The head component second mold portion 104 and the recessed portion 156 provide surface features 162 which, upon filling the head component mold 100, provide depressions 302 in the articulating head 300 of the final implant, as shown in
It is understood that in such embodiments, the surface features 162 can be included on either of the head component first mold portion 102 or the head component second mold portion 104. The surface area of the temporary implant 300 can be increased by from about 1% up to 50% or more depending on the combination of surface area increasing features 162 employed in the mold 100. An exemplary, but non-limiting, benefit of the increased surface area is the increased amount of antibiotic or other therapeutic material (i.e.: drugs, vitamins, etc.) from the surface of the temporary implant to the defect site. The increased delivery of the antibiotic or other therapeutic material expedites healing and minimizes the recovery time of the patient.
Referring to FIGS. 1 and 5A-5B, the head connector 110 can define a hollow chamber (shown in phantom) formed by a metal insert contained within the head component mold 100. The head connector 110 exterior surface defines flats 111 to assist in the fit of the head connector 110. In addition, the flats 111 prevent the rotation of the head connector 110 in the cement. The head connector interior surface defines a shoulder 113 which mimics the outer contour of the head connector. The shoulder 113 sits atop the head connector alignment member 112 as will be detailed later herein. Exemplary metals for the head connector 110 include stainless steel, titanium, cobalt, and the like and various alloys thereof. The head connector 110 can mate with the femoral stem component using a taper fit, such as a Morse taper, as a non-limiting example. The head connector 110 can optionally include surface roughening features or a surface texture to facilitate placement and fit with the stem implant 400.
In various embodiments, the head connector 110 is a female connector and is contained within the head component mold 100 such that upon filling the head component mold 100 with a material, such as a bone cement, a void volume will be defined in the articulating head portion of the temporary implant having a volume that is roughly equivalent to the void volume defined by the head connector 110. In still other embodiments, the head connector 110 can be a male connector and is contained at a region of the head component mold 100 and does not define a hollow region within the head component mold 100 upon filling the head mold with the material.
In either embodiment, the head connector 110 is fixed in the head component mold 100 so that it is not inadvertently displaced. The fixation of the head connector 110 is facilitated by the head connector alignment member 112. Further the head connector alignment member 112 can be made of a material which facilitates easy removal of the head connector alignment member 112 from the head connector 110. In various embodiments, the head connector alignment member 112 can be formed of a polymer material, such as polyethylene or PEEK. The head connector alignment member 112 can be formed of the same material as the head component mold 100 or it can be made of a different material.
The head connector alignment member 112 includes a tapered region 115, an abutment member 117, and a cylindrical region 119. As depicted, the head connector alignment member 112 can be hollow. The tapered region 115 mates with the interior region 166 of the head connector 110. The abutment member 117 is sized to extend beyond the perimeter of the opening 158 to prevent the tapered region 115 from passing therethrough. The head connector alignment member 112 is retained in the head component second mold portion 104 by a lip 158 or ring about the interior region 156 of the head component second mold portion 104. The lip 158 and the head connector alignment member 112 can be maintained in contact using friction between the materials. Any other suitable retention technique can also be employed in accords with the present teachings.
Inclusion of the head connector alignment member 112 in the head component mold 100 helps maintain a material-tight integrity of the head component mold 100 and prevents leakage of a filling material therefrom. Further, in various embodiments, the hollow alignment member 112 facilitates access to the head connector 110 and allows a user to press against the head connector 110 to free the implant from the mold 104. In various embodiments, the head component mold 100 and the head connector alignment member 112 can be provided as a single unit. The head connector alignment member 112 is used for temporary securing purposes only and is not included in the final articulating head implant 300.
To connect the head component mold first portion 102 with the head component second mold portion 104, the offset connection components 124a and 124b are interlaced to form a piano hinge which is connected over the pin or rod 128. The pin 128 is placed through the openings 126a formed in the connection component 124a of the head component mold first portion 102. This can be achieved by providing a pin 128 which has previously been insert molded into the openings 124a. Next, the pin 128 is hooked underneath the hook shaped passages 126b to removably connect the head component mold first portion 102 with the head component second mold portion 104. In addition, the removal of the pin 128 allows head 300 to be removed from portion 104.
Further, with reference to
The threaded opening 160 in the head component second mold portion 104 provides an access through which to deliver a material to fill the head component mold 12. It is understood that the threaded opening 160 can be defined at any region of the head component mold 100 and is not limited to placement on the second mold portion 104. The threaded opening 160 can be sized to accommodate a nozzle of a delivery device or a syringe through which a material is delivered to the head component mold 100.
Turning to
Turning to
Referring to
As shown in
As illustrated, the surface features 262a are raised protrusions which will form dimples 402a in the femoral stem 400 at a proximal region 410 of the femoral stem implant 400, as shown in
The surface features 262a, 262b, and 262c detailed here are merely exemplary, and it is understood that any combination of surface features or single-type of surface features can be used within the scope of the present teachings, including the types of surface features detailed with respect to the head component mold 100. Further, similar to the surface features used with the head component mold 100, the various surface features 262a, 262b, and 262c of the stem component mold 200 provide an increase in the surface area of the femoral implant 400 which includes the exemplary, but non-limiting, benefit of the increased amount of antibiotic or other therapeutic material (i.e.: drugs, vitamins, etc.) from the surface of the temporary implant 400 to the patient to thereby expedite healing and minimize the recovery time of the patient.
The stem component mold second portion 204 is generally a mirror image of the stem component mold first portion 202 with a few additions. The stem component mold second portion 204 includes an inner surface 254, an outer surface 256, and a connection component 224b which further defines a series of hooks 226b to accommodate the connection component pin 228. The perimeter of the stem component mold second portion 204 forms an edge 231. A threaded opening 260 is provided on the outer surface 256 which functions in multiple capacities as will be detailed later herein. The proximal end of the stem component mold second portion 204 defines a fixation screw 212 receiving region portion 238b. The stem component mold second portion 204 perimeter 231 defines a plurality of screw receiving threaded openings 234b dispersed therein. In various embodiments, the openings 234b include a sonically inserted metal nut (not shown) to receive the screw 212. Similar to the head component 100, the screw receiving openings 234a define ledges 235 which can be manipulated to provide a fold-over 237 (
Turning to
Returning to
The stem insert 210 includes a stem neck portion 284 and a stem connector 286. The stem neck portion 284 is designed to fit between the opening formed when the curved recessed regions 290a and 290b of the stem mold first component 202 and stem mold second component 204 are joined. The stem connector 286 can be in the form of a Morse taper through which to connect to the head connector portion 110 of
With further reference to
To connect the stem component mold 200 together, the rod 228 is passed through the alternating hook shaped openings 224a and 224b of the opposing stem component mold portions 202 and 204, respectively, as shown in
The present teachings further provide methods of providing and using the modular cement mold. Although the methods are disclosed as used with certain embodiments of the present teachings, it is understood that the methods disclosed can be used with any of the mold embodiments detailed above herein.
First, a surgeon or assistant will mix the appropriate antibiotic loaded cement or add an antibiotic to the particular cement. It is understood that the preparation of the cement is performed according to the label instructions of the particular cement. For example, about two grams of antibiotic are mixed with each 40 gram packet of bone cement powder which is then mixed with a corresponding number of 20 milliliter ampoules of a liquid monomer. The bone cement can be a poly-methyl-methacrylate (PMMA) cement such as those produced under the trade names Generation 4™, CMW1, CMW2, CMW3, Zimmer Dough Type, or Zimmer LVC, or a MMA-styrene copolymer cement such as that produced under the trade names Howmedica, Simplex P, or Zimmer Osteobond, or an MMA-methyl acrylate copolymer such as that produced under trade names Cobalt™ G-HV or Cobalt™ HV sold by Biomet. Once the appropriate antibiotic loaded bone cement is mixed, the bone cement is put within a delivery device, such as a cement gun. It is understood that an adaptor may be employed to accommodate different types of delivery devices or cement guns.
The appropriately sized mold portions 102 and 104 and mold portions 202 and 204 along with the related appropriately sized components, such as the head connector 110 or stem insert 210 are selected to form a customized fit for both the articulating head 300 and femoral component 400. It is understood that the head component 300 and the stem component 400 can be varied in size to provide further customization of the temporary implant depending on the patient's needs. The modular systems of the present teachings can be provided as a plurality of differently sized head components 100, stem molds 200, and related subcomponents. Once the appropriately sized components are selected, a surgeon will generally grasp the head component mold 100 and threadedly engage the nozzle of the delivery device into the access port 160. With the nozzle substantially sealing the access port 160, the surgeon will engage the delivery device to dispense out the bone cement within the inner cavity 106a and 106b formed within the head component mold 100. After removing the cement delivery device, the surgeon then secures the self-cleaning cap 168 into the opening 160. Any excess cement will extrude out of the self-cleaning cap 168 and facilitate providing a flush implant.
The assembled mold 200 is connected as follows. It is understood that in various embodiments, the mold 200 can be provided pre-assembled or partially pre-assembled where some components must be connected by the user prior to use. In the assembled device, the stem component mold first portion 202 and stem component mold second portion 204 are connected using the connector 228 which is interlaced between the series of offset hooks 226a and 226b. The stem insert 210 is then aligned in the cavity formed from elements 206a and 206b and secured via fixation member 212. The recess or dispersion region 292 of the stem insert 210 is arranged to be aligned with the opening 260 defined in the stem component mold second portion 204 to provide proper flow of the material around the stem insert 210. The stem insert 210 is then fixed into the mold portions 202 and 204 using the screw 212. The stem component mold first portion 202 and second portion 204 are then secured with the screws 236 in each respective pair of bores 234a and 234b. As mentioned above, and as shown in
Once the head component mold 100 and stem component mold 200 are filled, the assemblies can be placed on a nearby surface, such as a surgical table, to allow the cement to cure and cool while the surgeon moves on to another task, thereby substantially increasing the efficiency and reducing the time for the surgical procedure. Once the bone cement has sufficiently cured, the surgeon can grasp the head mold component 100 and remove the screw 136 disposed in the opening formed by elements 134a and 134b. The user attempts to back the screw 136 out of the threaded opening 134b and towards the ledge 135. The screw 136 then engages the ledge 135 and fold-over region 137 and is prevented from passing beyond the fold-over region 137 and back through the opening 134a. The retention force of the ledge 135 and fold-over region 137 against the rotating screw 136 pries the two mold component portions 102 and 104 apart to free the implant. Similarly, the surgeon removes any other screws 236 from the openings formed by the pairs of bores 234a and 234b using leverage from the ledges 235 and fold-over regions 237.
The stem component 400 of the temporary hip implant can then be simply engaged in the intramedullary canal of the host femur. The air vent 402c formed in the stem component 400 facilitates the passage of air from within the host femur to be expelled upon insertion of the stem component 400.
The head component 300 is then disposed over the stem connector 286 via the head connector 110, and the temporary implant is assembled. This implanted head component 300 and stem component 400 allow the distended joint to be subsequently re-engaged with the temporary implant to enable limited non-load bearing movement by the patient. The temporary implant allows the patient to generally sit up or be transported out of a hospital during the temporary recovery stage prior to having a revision type prosthesis subsequently implanted. During this time the antibiotic in the bone cement leaches out to the infected area and soft-tissue tension is maintained.
The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the invention, and all such modifications are intended to be included within the scope of the invention.
This application is a continuation-in-part of U.S. patent application Ser. No. 11/955,601 filed on Dec. 13, 2007. The entire disclosure of the above application is incorporated herein by reference.
Number | Name | Date | Kind |
---|---|---|---|
1525126 | Goldstein | Feb 1925 | A |
2347567 | Kresse | Apr 1944 | A |
2527992 | Greenberg | Oct 1950 | A |
2954144 | Elam et al. | Sep 1960 | A |
3014614 | Carroll et al. | Dec 1961 | A |
3102536 | Rose et al. | Sep 1963 | A |
3144966 | Cook | Aug 1964 | A |
3580484 | Schneider | May 1971 | A |
3774244 | Walker | Nov 1973 | A |
3857932 | Shepherd et al. | Dec 1974 | A |
3882858 | Klemm | May 1975 | A |
3907245 | Linder | Sep 1975 | A |
3964106 | Hutter, Jr. et al. | Jun 1976 | A |
3966166 | Elliott | Jun 1976 | A |
4059684 | Gross et al. | Nov 1977 | A |
4191740 | Heusser et al. | Mar 1980 | A |
4235578 | Cosmi | Nov 1980 | A |
4322398 | Reiner et al. | Mar 1982 | A |
4375810 | Belykh et al. | Mar 1983 | A |
4456573 | Ragazzini et al. | Jun 1984 | A |
4550723 | Belykh et al. | Nov 1985 | A |
4579700 | Cavender | Apr 1986 | A |
4581028 | Fox, Jr. et al. | Apr 1986 | A |
4610692 | Eitenmuller et al. | Sep 1986 | A |
4615705 | Scales et al. | Oct 1986 | A |
4624673 | Meyer | Nov 1986 | A |
4721390 | Lidgren et al. | Jan 1988 | A |
4739963 | Parmacek et al. | Apr 1988 | A |
4749585 | Greco et al. | Jun 1988 | A |
4750905 | Koeneman et al. | Jun 1988 | A |
4797282 | Wahlig et al. | Jan 1989 | A |
4803028 | Torossian et al. | Feb 1989 | A |
4853225 | Wahlig et al. | Aug 1989 | A |
4869906 | Dingeldein et al. | Sep 1989 | A |
4882149 | Spector | Nov 1989 | A |
4888024 | Powlan | Dec 1989 | A |
4900546 | Posey-Dowty et al. | Feb 1990 | A |
4917589 | Manderson | Apr 1990 | A |
4919666 | Buchhorn et al. | Apr 1990 | A |
4950300 | Langlais | Aug 1990 | A |
5015257 | Crowninshield et al. | May 1991 | A |
5033712 | Ravet | Jul 1991 | A |
5061286 | Lyle | Oct 1991 | A |
5098620 | Bradley et al. | Mar 1992 | A |
5108452 | DeMane et al. | Apr 1992 | A |
5123927 | Duncan et al. | Jun 1992 | A |
5133771 | Duncan et al. | Jul 1992 | A |
5141521 | Wenner | Aug 1992 | A |
5236457 | Devanathan | Aug 1993 | A |
5328262 | Lidgren et al. | Jul 1994 | A |
5370221 | Magnusson et al. | Dec 1994 | A |
5501520 | Lidgren et al. | Mar 1996 | A |
5501687 | Willert et al. | Mar 1996 | A |
5538514 | Hawkins | Jul 1996 | A |
5858020 | Johnson et al. | Jan 1999 | A |
5951160 | Ronk | Sep 1999 | A |
6146419 | Eaton | Nov 2000 | A |
6155812 | Smith et al. | Dec 2000 | A |
6258089 | Campbell et al. | Jul 2001 | B1 |
6286670 | Smith | Sep 2001 | B1 |
6352659 | Clark et al. | Mar 2002 | B1 |
6361731 | Smith et al. | Mar 2002 | B1 |
7018089 | Wenz et al. | Mar 2006 | B2 |
7396495 | Friesner | Jul 2008 | B2 |
7878785 | Cathcart et al. | Feb 2011 | B2 |
20020001694 | Wetzel | Jan 2002 | A1 |
20030065398 | Cueille et al. | Apr 2003 | A1 |
20030122285 | Crane et al. | Jul 2003 | A1 |
20030155381 | Chan | Aug 2003 | A1 |
20050004680 | Saladino et al. | Jan 2005 | A1 |
20050027302 | Cueille et al. | Feb 2005 | A1 |
20050143828 | Collins et al. | Jun 2005 | A1 |
20060109737 | Wilander | May 2006 | A1 |
20070016215 | Wilander et al. | Jan 2007 | A1 |
20070026098 | Lemaistre et al. | Feb 2007 | A1 |
20070211563 | De Vries | Sep 2007 | A1 |
20070222114 | Ziran et al. | Sep 2007 | A1 |
20090234034 | Blanco | Sep 2009 | A1 |
20100046315 | Merkhan et al. | Feb 2010 | A1 |
20110064840 | Borgatti et al. | Mar 2011 | A1 |
Number | Date | Country |
---|---|---|
297039717 | Sep 1998 | DE |
0016480 | Oct 1980 | EP |
0129531 | Dec 1984 | EP |
166724 | Jan 1986 | EP |
1005900 | Jun 2000 | EP |
2014429 | Jan 2009 | EP |
2639820 | Jun 1990 | FR |
2898039 | Sep 2007 | FR |
WO-8705492 | Sep 1987 | WO |
WO-9851240 | Dec 1998 | WO |
Number | Date | Country | |
---|---|---|---|
20090175978 A1 | Jul 2009 | US |
Number | Date | Country | |
---|---|---|---|
Parent | 11955601 | Dec 2007 | US |
Child | 12390084 | US |