Patent Publication Number: US-2013231744-A1

Title: Grommet for use with surgical implant

Description:
RELATED INVENTION 
     This application claims priority on U.S. Provisional Application Ser. No. 61/605,379, filed Mar. 1, 2012 and entitled “GROMMET FOR USE WITH SURGICAL IMPLANT”. As far as permitted, the contents of U.S. Provisional Application Ser. No. 61/605,379 are incorporated herein by reference. 
    
    
     BACKGROUND 
     It is well known that some people have problems with one or more joints in their body, including feet and/or hands. Treatment of such problems with the joints often entails to inserting of a surgical implant into the joint in order to stabilize the joint, while still allowing for good joint mobility, good joint load transfer and good joint purchase. Unfortunately, the treatment of such joint problems with existing surgical implants has not been entirely satisfactory. 
     SUMMARY 
     The present invention is directed toward a grommet for use with a surgical implant. In certain embodiments, the grommet comprises a base and a sleeve. The base can be positioned around a portion of the surgical implant. Additionally, the sleeve is connected to the base and extends away from the base. The sleeve includes an inner surface having a non-circular shape, and an outer surface that is substantially cylinder-shaped. 
     In some embodiments, the outer surface of the sleeve tapers as the sleeve extends away from the base. For example, in such embodiments, the outer surface of the sleeve can have a taper angle of between approximately 20.0 and 25.0 degrees. 
     Additionally, in certain embodiments, the sleeve can include one or more anti-rotation features that are positioned along the outer surface of the sleeve. The anti-rotation features can be varied. For example, the anti-rotation features can include one or more anti-rotation ribs that extend away from the outer surface of the sleeve, and/or one or more anti-rotation grooves that are formed into the outer surface of the sleeve. 
     In one embodiment, the base is inhibited from rotating relative to the portion of the surgical implant. 
     Further, in some embodiments, the surgical implant can include a stem, and the grommet can be positioned around a portion of the stem. In certain such embodiments, the stem has an outer surface having a first shape, and the inner surface of the sleeve has a second shape, the second shape being substantially similar to the first shape. This enables the grommet to fit snugly and securely around the stem. In one embodiment, the second shape can be non-circular such that the grommet is inhibited from rotating relative to the stem. 
     Additionally, in one embodiment, the present invention is further directed toward a surgical implant for implanting into bone material, the surgical implant including a stem and the grommet as described above that is positioned around the stem. Moreover, in such embodiment, the sleeve can include one or more anti-rotation features that are positioned along the outer surface of the sleeve, the anti-rotation features inhibiting the grommet from rotating relative to the bone material. 
     In another application, the present invention is directed toward a grommet for use with a surgical implant that can be implanted into bone material, the grommet comprising (i) a base that can be positioned around a portion of the surgical implant; and (ii) a sleeve that is connected to the base and extends away from the base, the sleeve including an outer surface that is substantially cylinder-shaped, and one or more anti-rotation features that are positioned along the outer surface of the sleeve. 
     Further, in still another application, the present invention is directed toward a grommet for use with a surgical implant that can be implanted into bone material, the surgical implant including a stem, the grommet comprising (i) a base that can be positioned around a portion of the stem; and (ii) a sleeve that is connected to the base and extends away from the base, the sleeve including (i) an inner surface having a non-circular shape such that the grommet is inhibited from rotating relative to the stem, (ii) an outer surface that is substantially cylinder-shaped, and (iii) one or more anti-rotation features that are positioned along the outer surface of the sleeve, wherein when the surgical implant is implanted into the bone material, the one or more anti-rotation features inhibit the grommet from rotating relative to the bone material. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The novel features of this invention, as well as the invention itself, both as to its structure and its operation, will be best understood from the accompanying drawings, taken in conjunction with the accompanying description, in which similar reference characters refer to similar parts, and in which: 
         FIG. 1A  is a side view of a part of a foot with a surgical implant implanted therein, the surgical implant including a pair of grommets having features of the present invention included therewith; 
         FIG. 1B  is a side view of the part of the foot and the surgical implant having the grommets of  FIG. 1A  included therewith, with the foot in a flexed position; 
         FIG. 2A  is a perspective view of an embodiment of a surgical implant including a pair of grommets having features of the present invention included therewith; 
         FIG. 2B  is a side view of the surgical implant including the pair of grommets of  FIG. 2A ; 
         FIG. 2C  is a top view of the surgical implant including the pair of grommets of  FIG. 2A ; 
         FIG. 2D  is a sectional view of the surgical implant including the pair of grommets taken on line D-D in  FIG. 2B ; 
         FIG. 3  is a perspective view of another embodiment of a surgical implant including a pair of grommets having features of the present invention included therewith; 
         FIG. 4A  is a perspective view of an embodiment of a grommet having features of the present invention; 
         FIG. 4B  is an end view of the grommet of  FIG. 4A ; 
         FIG. 4C  is a side view of the grommet of  FIG. 4A ; 
         FIG. 4D  is a top view of the grommet of  FIG. 4A ; 
         FIG. 5A  is a perspective view of another embodiment of a grommet having features of the present invention; 
         FIG. 5B  is an end view of the grommet of  FIG. 5A ; 
         FIG. 5C  is a side view of the grommet of  FIG. 5A ; 
         FIG. 5D  is a sectional view of the grommet taken on line D-D in  FIG. 5B ; 
         FIG. 5E  is another sectional view of the grommet taken on line E-E in  FIG. 5B ; 
         FIG. 6  is a simplified side view of an embodiment of a cannulated tapered drill bit that can be used with the present invention; 
         FIG. 7  is a simplified side view of another embodiment of a cannulated tapered drill bit that can be used with the present invention; and 
         FIG. 8  is a simplified side view of a wire that can be used with the drill bits of  FIGS. 6 and 7 . 
     
    
    
     DESCRIPTION 
     The present invention is directed to a grommet for use with a surgical implant that can be used to treat joint problems in the feet and/or hands. More specifically, in certain embodiments, the surgical implant and one or more grommets can be effectively utilized in conjunction with one another to treat one or more joint problems in the feet or toes, e.g., a metatarsal phalangeal joint or an interphalangeal joint of one of the toes. 
       FIG. 1A  is a side view of a part of a foot  10  with a surgical implant  12  implanted therein. As illustrated, the surgical implant  12  includes one or more grommets  14  (two are illustrated in  FIG. 1A ) having features of the present invention provided therewith. The grommets  14 , as disclosed in detail herein, can be used with a variety of different surgical implants. For example, suitable non-exclusive surgical implants  12  for use with the present invention can be as disclosed in (i) U.S. Pat. No. 6,319,284 issued to Rushdy et al. and assigned to Futura Biomedical LLC, (ii) U.S. Pat. No. D490,900 issued to Ogilvie et al. and assigned to Ascension Orthopedics, Inc., (iii) U.S. Pat. No. 3,875,594 issued to Swanson and assigned to Dow Corning Corporation, and (iv) U.S. Pat. No. 6,869,449 issued to Ball et al. and assigned to DePuy Orthopaedics, Inc. 
       FIG. 1A  illustrates one embodiment of the surgical implant  12  that may be used in conjunction with the grommets  14  that are disclosed in detail herein. As illustrated, the surgical implant  12  can be used to provide a replacement joint in the first metatarsal phalangeal joint  16  (sometimes referred to herein simply as the “joint”) between the metatarsal  18  and the proximal phalanx  20 . Alternatively, the surgical implant  12  can be used in another suitable joint. In this embodiment, the surgical implant  12  includes an implant body  22  having a proximal stem  24  (illustrated in phantom), a distal stem  26  (illustrated in phantom) and a hinge  28 . 
     In the embodiment of the surgical implant  12  illustrated in  FIG. 1A , the proximal stem  24  is sized and shaped to be inserted into a medullary canal in the metatarsal  18 . Somewhat similarly, the distal stem  26  is sized and shaped to be inserted into a medullary canal in the proximal phalanx  20 . The hinge  28  is positioned substantially between and connects the proximal stem  24  and the distal stem  26 . Additionally, the hinge  28  allows for relative movement, e.g., flexing, between the proximal stem  24  and the distal stem  26  during movement of the foot  10 . 
     In certain embodiments, the one or more grommets  14  can include a first grommet  14 A and a second grommet  14 B. For example, as illustrated in  FIG. 1A , the first grommet  14 A can be positioned around a portion of the proximal stem  24  substantially adjacent to the hinge  28 , and the second grommet  14 B can be positioned around a portion of the distal stem  26  substantially adjacent to the hinge  28 . Additionally and/or alternatively, one or both of the first grommet  14 A and the second grommet  14 B can be integrally formed with the surgical implant  12 . 
     As an overview, the grommets  14 A,  14 B are uniquely designed to maintain the surgical implant  12  positioned appropriately within the joint, e.g., the first metatarsal phalangeal joint  16 , while allowing certain relative movement between the stems, i.e. the proximal stem  24  and the distal stem  26 , and the corresponding bones  18 ,  20 , and between the stems  24 ,  26  and the corresponding grommets  14 A,  14 B. More specifically, in this embodiment, the first grommet  14 A allows the proximal stem  24  to move relative to the metatarsal  18 , i.e. within the medullary canal, and/or relative to the first grommet  14 A, while maintaining the proper positioning of the proximal stem  24  within the first metatarsal phalangeal joint  16 . Somewhat similarly, the second grommet  14 B allows the distal stem  26  to move relative to the proximal phalanx  20 , i.e. within the medullary canal, and/or relative to the second grommet  14 B, while maintaining the proper positioning of the distal stem  26  within the first metatarsal phalangeal joint  16 . 
     With this design, the grommets  14 A,  14 B can limit the direct interface between the surgical implant  12  and the bones  18 ,  20 , thereby inhibiting discomfort experienced by the patient that may occur due to such direct interface. For example, the surgical implant  12  may be made of a silicone material, and relative movement between the surgical implant  12  and the bone material  18 ,  20  at an interface may result in certain debris being generated within the joint  16 . The use of grommets  14 A,  14 B as described herein, can inhibit the generation of such debris within the joint  16 . Additionally, the grommets  14 A,  14 B remain substantially stationary relative to the bones  18 ,  20 , while ensuring that the surgical implant  12  remains properly positioned within the joint  16 . Moreover, the grommets  14 A,  14 B are designed to allow for improved range of motion of the joint  16  after insertion of the surgical implant  12   
       FIG. 1B  is a side view of the part of the foot  10  and the surgical implant  12  having the grommets  14 A,  14 B of  FIG. 1A  included therewith. Additionally,  FIG. 1B  illustrates the foot  10  in a flexed position. In particular,  FIG. 1B  demonstrates the ability of the foot  10  to properly flex with the surgical implant  12  having the grommets  14 A,  14 B included therewith inserted within the joint  16 . As illustrated, during flexing of the foot  10 , the grommets  14 A,  14 B assist in maintaining the surgical implant  12  properly positioned within the joint  16 . Although the flexing of the foot  10  may involve some movement between the proximal stem  24  (illustrated in phantom) and the medullary canal in the metatarsal  18 , and/or between the distal stem  26  (illustrated in phantom) and the medullary canal in the proximal phalanx  20 , the grommets  14 A,  14 B remain substantially stationary relative to the bones  18 ,  20 . 
       FIG. 2A  is a perspective view of an embodiment of a surgical implant  212  including a pair of grommets  214 A,  214 B having features of the present invention included therewith. The design of the surgical implant  212  and the design of the grommets  214 A,  214 B can be varied according to the specific requirements for the surgical implant  212 . 
     As illustrated in  FIG. 2A , the surgical implant  212  includes an implant body  222  having a proximal stem  224 , a distal stem  226 , and a hinge  228 . 
     As discussed above, the proximal stem  224  and the distal stem  226  are sized and shaped to fit within canals or holes in the bones on either side of a joint  16  (illustrated in  FIG. 1A ). 
     The hinge  228  is positioned substantially between and connects the proximal stem  224  and the distal stem  226 . Additionally, the hinge  228  allows for relative movement, e.g., flexing, between the proximal stem  224  and the distal stem  226  during movement of the foot  10  (illustrated in  FIG. 1A ). As illustrated, the hinge  228  can include a proximal hinge buttress  230 , a distal hinge buttress  232 , and a hinge center section  234  that extends between and connects the proximal hinge buttress  230  and the distal hinge buttress  232 . The hinge center section  234  is designed to allow for proper and necessary flexing of the surgical implant  212  during flexing of the joint  16  into which the surgical implant  212  is inserted. 
     Additionally, as shown in  FIG. 2A , the first grommet  214 A can be positioned substantially about a portion of the proximal stem  224  substantially adjacent to the proximal hinge buttress  230 . Somewhat similarly, the second grommet  214 B can be positioned substantially about a portion of the distal stem  226  substantially adjacent to the distal hinge buttress  232 . Alternatively, the first grommet  214 A can be positioned somewhat spaced apart from the proximal hinge buttress  230  and/or the second grommet  214 B can be positioned somewhat spaced apart from the distal hinge buttress  232 . 
     Further, in certain embodiments, the grommets  214 A,  214 B have a substantially cylindrical outer surface  238  that tapers slightly along with the taper of the corresponding stem  224 ,  226  as the distance from the corresponding hinge buttress  230 ,  232  increases. This tapering of the outer surface  238  is designed to facilitate surgical preparation. Stated in another manner, the outer surface  238  of the grommets  214 A,  214 B has a substantially circular cross-section that tapers slightly as the distance from the hinge  228  increases, such that the grommets  214 A,  214 B are shaped as a portion of a cone, i.e. a frustum of a cone. 
     Additionally, in some embodiments, the grommets  214 A,  214 B can include one or more anti-rotation features  240 , e.g., anti-rotation ribs or anti-rotation grooves, along the outer surface  238  of the grommet  214 A,  214 B so as to inhibit relative rotation between the grommet  214 A,  214 B and the bone into which the surgical implant  212  and the grommet  214 A,  214 B is inserted. Moreover, the design of the grommets  214 A,  214 B enables the use of easy-to-use cannulated instrumentation for preparation of the bone for insertion of the surgical implant  212  with grommets  214 A,  214 B. For example, no broaching is necessary because the outer surface  238  of the grommets  214 A,  214 B is cone-shaped, which facilitates the use of a drill rather than broach. Further, as provided herein, cannulated tapered drill bits can be used to prepare the bone as necessary over a wire. 
       FIG. 2B  is a side view of the surgical implant  212  including the pair of grommets  214 A,  214 B of  FIG. 2A . In particular,  FIG. 2B  illustrates certain additional details regarding the design of the surgical implant  212 . For example, in this embodiment, the proximal stem  224  is angled slightly in the upward direction relative to the distal stem  226  to correspond with the relative angling of the bones, e.g., the metatarsal  18  and the proximal phalanx  20  illustrated in  FIG. 1A , when the foot  10  (illustrated in  FIG. 1A ) is in a relaxed position. 
     Additionally, as shown in  FIG. 2B , the hinge center section  234  includes an upper portion  242  and a lower portion  244  that can be integrally formed with one another. Further, the upper portion  242  can be somewhat V-shaped, and the lower portion  244  can be somewhat inverted V-shaped. Moreover, in certain embodiments, the upper portion  242  is somewhat larger than the lower portion  244 . Stated in another manner, the V-shape of the upper portion  242  is somewhat deeper than the inverted V-shape of the lower portion  244 . 
       FIG. 2C  is a top view of the surgical implant  212  including the pair of grommets  214 A,  214 B of  FIG. 2A . More particularly,  FIG. 2C  illustrates still further details regarding the design of the surgical implant  212 . For example, as shown in  FIG. 2C , the hinge center section  234  can be somewhat wider directly adjacent to the proximal hinge buttress  230  than it is directly adjacent to the distal hinge buttress  232 . Stated in another manner, the hinge center section  234  tapers inwardly slightly from the proximal hinge buttress  230  toward the distal hinge buttress  232 . 
     Additionally, in this embodiment, the proximal stem  224  is somewhat larger, i.e. wider and longer, than the distal stem  226 . Moreover, because the proximal stem  224  is larger than the distal stem  226 , the first grommet  214 A is also somewhat larger, i.e. larger diameter around the outer surface  238 , than the second grommet  214 B. 
       FIG. 2D  is a sectional view of the surgical implant  212  including the pair of grommets  214 A,  214 B taken on line D-D in  FIG. 2B . It should be noted that neither the proximal stem  224  nor the first grommet  214 A are visible in  FIG. 2D . 
     In some embodiments, as shown in  FIG. 2D , the grommets  214 A,  214 B have an internal shape, i.e. an inner surface  246 , that matches the shape of an outer surface  248  of the corresponding stem  224 ,  226 . Additionally, the shape of the inner surface  246  of the grommets  214 A,  214 B and/or the shape of the outer surface  248  of the stems  224 ,  226  can include anti-rotation features such that relative rotation between the stems  224 ,  226  and the grommets  214 A,  214 B is effectively inhibited. For example, in one embodiment, the inner surface  246  of the grommets  214 A,  214 B and/or the outer surface  248  of the stems  224 ,  226  can have a non-circular shape that does not allow for relative rotation between the stems  224 ,  226  and the grommets  214 A,  214 B. Additionally and/or alternatively, the stems  224 ,  226  and the grommets  214 A,  214 B can include specific corresponding features, e.g., ribs and grooves, that are designed to engage one another so as to inhibit the relative rotation between the stems  224 ,  226  and the grommets  214 A,  214 B. 
       FIG. 3  is a perspective view of another embodiment of a surgical implant  312  including a pair of grommets  314 A,  314 B having features of the present invention included therewith. As illustrated, the surgical implant  312  and the grommets  314 A,  314 B are substantially similar to the surgical implant  212  and the grommets  214 A,  214 B illustrated and described above in relation to  FIGS. 2A-2D . For example, in this embodiment, the surgical implant  312  again includes a proximal stem  324 , a distal stem  326 , and a hinge  328  that are substantially similar to the proximal stem  224 , the distal stem  226 , and the hinge  228  illustrated and described above in relation to  FIGS. 2A-2D . 
     Additionally, similar to the previous embodiment, the surgical implant  312  again includes the first grommet  314 A that is positioned substantially about a portion of the proximal stem  324  substantially adjacent to a proximal hinge buttress  330 , and the second grommet  314 B that is positioned substantially about a portion of the distal stem  326  substantially adjacent to a distal hinge buttress  332 . However, in this embodiment, the grommets  314 A,  314 B are integrally formed with the proximal stem  324  and the distal stem  326 , respectively. With this design, although flexing of the foot  10  (illustrated in  FIG. 1A ) may result in some relative movement between the grommets  314 A,  314 B and the bones into which the surgical implant is implanted, the interface between the grommets  314 A,  314 B and the bones will be much less than may otherwise exist between the stems  324 ,  326  and the bones. 
       FIG. 4A  is a perspective view of an embodiment of a grommet  414  having features of the present invention. In particular,  FIG. 4A  illustrates a perspective view of the grommet  414  including various features as described in detail herein above. For example, in one embodiment, the grommet  414  illustrated in  FIG. 4A  is sized and shaped such that it can be positioned about the distal stem  226  (illustrated, for example, in  FIG. 2A ) prior to insertion of the surgical implant  212  (illustrated, for example, in  FIG. 2A ). Stated in another manner, in such embodiment, the grommet  414  can be used as the second grommet  14 B illustrated in  FIG. 1A . Alternatively, the grommet  414  can be used for other suitable purposes. 
     The design of the grommet  414  can be varied to suit the specific design requirements of the surgical implant  212 . In the embodiment illustrated in  FIG. 4A , the grommet  414  includes a base  450  and a sleeve  452 . 
     As illustrated, the base  450  can be a flat, ring-like member that fits around the distal stem  226  of the surgical implant  212 . More specifically, the base  450  can be sized and shaped to be positioned around the distal stem  226  substantially adjacent to the hinge  228  (illustrated in  FIG. 2A ). In one embodiment, the base  450  can be positioned around the distal stem  226  substantially adjacent to the distal hinge buttress  232  (illustrated in  FIG. 2A ). Alternatively, the grommet  414  can be positioned relative to the surgical implant  212  in a different manner. For example, the grommet  414  can be positioned around the distal stem  226  spaced apart from the hinge  228 . 
     Additionally, the sleeve  452  can be fixedly secured to and/or integrally formed with the base  450 . Further, as illustrated, the sleeve  452  extends away from the base  450 . In one embodiment, the sleeve  452  can be sized and shaped to be positioned around the distal stem  226  of the surgical implant  212 . Moreover, the sleeve  452  can have an outer surface  438  that is sized and shaped to fit securely within the medullary canal in a bone, e.g., within the medullary canal in the proximal phalanx  20  (illustrated in  FIG. 1A ). With this design, the grommet  414  can remain substantially stationary relative to the proximal phalanx  20  during any flexing of the foot  10  (illustrated in  FIG. 1A ). Additionally, the grommet  414  can thus minimize and/or inhibit any direct interface between the distal stem  226  and the proximal phalanx  20  that may otherwise cause discomfort for the patient. 
     Further, in certain embodiments, the grommet  414  can be made from titanium, stainless steel, polyether ether ketone (PEEK), a cobalt-chromium alloy, or another suitable material. 
       FIG. 4B  is an end view of the grommet  414  of  FIG. 4A . In particular,  FIG. 4B  illustrates certain additional details and features of the grommet  414  illustrated in  FIG. 4A . For example, in one embodiment,  FIG. 4B  illustrates that the base  450  of the grommet  414  can include a substantially flat bottom  454  and a rounded upper portion  456 . In such embodiment, when the surgical implant  212  (illustrated in  FIG. 2A ) is implanted in the patient, e.g., in the foot  10  (illustrated in  FIG. 1A ) of the patient, the bottom  454  of the base  450  of the grommet  414  will be positioned below the distal stem  226  (illustrated in  FIG. 2A ) and toward the bottom of the foot  10 . Alternatively, the base  450  can have a different design than that illustrated in  FIG. 4B . For example, in one embodiment, the base  450  can be substantially completely circle-shaped. 
     Additionally,  FIG. 4B  further illustrates the general shape of the outer surface  438  of the sleeve  452  of the grommet  414 . In particular, as illustrated in this embodiment, the outer surface  438  of the sleeve  452  is substantially cylinder-shaped or frustum-shaped. Moreover, one or more anti-rotation features  440  can be positioned about the outer surface  438  of the sleeve  452  so as to inhibit relative rotation between the grommet  414  and the bone, e.g., the proximal phalanx  20  (illustrated in  FIG. 1A ), into which the surgical implant  212  and the grommet  414  are inserted. For example, the anti-rotation features  440  can include one or more anti-rotation ribs that extend away from the rest of the outer surface  438  of the sleeve  452  and/or one or more anti-rotation grooves that are formed into the outer surface  438  of the sleeve  452 . Alternatively, the anti-rotation features  440  can have a different design. Still alternatively, the outer surface  438  of the sleeve  452  can be another suitable design or shape. 
     Further,  FIG. 4B  also illustrates the general shape of the inner surface  446  of the grommet  414 , i.e. the inner surface  446  of the base  450  and/or the sleeve  452  of the grommet  414 . The shape of the inner surface  446  can be designed to match the shape of the outer surface of the distal stem  226 . As illustrated in this embodiment, the inner surface  446  can have a non-circular shape that inhibits any relative rotation between the grommet  414  and the outer surface of the distal stem  226 . For example, the inner surface  446  can be substantially rectangle-shaped, with rounded corners. Alternatively, the inner surface  446  can have another suitable non-circular shape, e.g., square, oval, triangle, hexagon, or other suitable shape. 
       FIG. 4C  is a side view of the grommet  414  of  FIG. 4A . In particular,  FIG. 4C  also illustrates certain additional details and features of the grommet  414  illustrated in  FIG. 4A . For example,  FIG. 4C  illustrates that the outer surface  438  of the sleeve  452  tapers slightly as the sleeve  452  extends away from the base  450  of the grommet  414 . As noted above, the taper of the outer surface  438  generally corresponds to the taper of the corresponding stem, e.g., the distal stem  226  illustrated in  FIG. 2A , about which the grommet  414  is positioned. 
     Additionally,  FIG. 4C  further illustrates an inner taper angle  458  of the inner surface  446  (illustrated in phantom) of the sleeve  452  as the sleeve  452  extends away from the base  450 . The inner taper angle  458  largely follows the taper of the corresponding stem, e.g., the distal stem  226  illustrated in  FIG. 2A , about which the grommet  414  is positioned. In certain embodiments, the inner taper angle  458  can be between approximately 13.0 and 18.0 degrees. For example, in some non-exclusive alternative embodiments, the inner taper angle  458  can be approximately, 13.0, 13.5, 14.0, 14.5, 15.0, 15.5, 16.0, 16.5, 17.0, 17.5 or 18.0 degrees. Alternatively, the inner taper angle  458  can be greater than 18.0 degrees, less than 13.0 degrees, or some other value between 13.0 and 18.0 degrees. 
     Moreover,  FIG. 4C  illustrates a depth  460  of the grommet  414  from the base  450  to the end of the sleeve  452  away from the base  450 . In certain embodiments, the depth  460  of the grommet  414  can be between approximately 0.10 inches and 0.20 inches. For example, in certain non-exclusive alternative embodiments, the depth  460  of the grommet  414  can be approximately 0.10, 0.125, 0.15, 0.175 or 0.20 inches. Alternatively, the depth  460  can be greater than 0.20 inches, less than 0.10 inches, or some other value between 0.10 and 0.20 inches. 
       FIG. 4D  is a top view of the grommet  414  of  FIG. 4A . More specifically,  FIG. 4D  illustrates an outer taper angle  462  of the outer surface  438  of the sleeve  452  as the sleeve  452  extends away from the base  450 . In certain embodiments, the outer taper angle  462  can be between approximately 20.0 and 30.0 degrees. For example, in some non-exclusive alternative embodiments, the outer taper angle  462  can be approximately, 20.0, 22.0, 24.0, 26.0, 28.0 or 30.0 degrees. Alternatively, the outer taper angle  462  can be greater than 30.0 degrees, less than 20.0 degrees, or some other value between 20.0 and 30.0 degrees. 
       FIG. 5A  is a perspective view of another embodiment of a grommet  514  having features of the present invention. In particular,  FIG. 5A  illustrates a perspective view of the grommet  514  including various features as described in detail herein above. For example, in one embodiment, the grommet  514  illustrated in  FIG. 5A  is sized and shaped such that it can be positioned about the proximal stem  224  (illustrated, for example, in  FIG. 2A ) prior to insertion of the surgical implant  212  (illustrated, for example, in  FIG. 2A ). Stated in another manner, in such embodiment, the grommet  514  can be used as the first grommet  14 A illustrated in  FIG. 1A . Alternatively, the grommet  514  can be used for other suitable purposes. 
     The grommet  514  illustrated in  FIG. 5A  is somewhat similar to the grommet  414  illustrated and described in relation to  FIGS. 4A-4D . For example, the grommet  514  includes a base  550  and a sleeve  552  that are somewhat similar to the base  450  and the sleeve  452  illustrated and described above. 
     In this embodiment, the base  550  can be a flat, ring-like member that fits around the proximal stem  224  of the surgical implant  212 . More specifically, the base  550  can be sized and shaped to be positioned around the proximal stem  224  substantially adjacent to the hinge  228  (illustrated in  FIG. 2A ). In one embodiment, the base  550  can be positioned around the proximal stem  224  substantially adjacent to the proximal hinge buttress  230  (illustrated in  FIG. 2A ). Alternatively, the grommet  514  can be positioned relative to the surgical implant  212  in a different manner. For example, the grommet  514  can be positioned around the proximal stem  224  spaced apart from the hinge  228 . 
     Additionally, the sleeve  552  can be fixedly secured to and/or integrally formed with the base  550 . Further, the sleeve  552  extends away from the base  550 . In one embodiment, the sleeve  552  can be sized and shaped to be positioned around the proximal stem  224  of the surgical implant  212 . Moreover, the sleeve  552  can have an outer surface  538  that is sized and shaped to fit securely within the medullary canal in a bone, e.g., within the medullary canal in the metatarsal  18  (illustrated in  FIG. 1A ). With this design, the grommet  514  can remain substantially stationary relative to the metatarsal  18  during any flexing of the foot  10  (illustrated in  FIG. 1A ). Additionally, the grommet  514  can thus minimize and/or inhibit any direct interface between the proximal stem  224  and the metatarsal  18  that may otherwise cause discomfort for the patient. 
       FIG. 5B  is an end view of the grommet  514  of  FIG. 5A . In particular,  FIG. 5B  illustrates certain additional details and features of the grommet  514  illustrated in  FIG. 5A . Similar to the previous embodiment, the base  550  of the grommet  514  can again include a substantially flat bottom  554  and a rounded upper portion  556 . Alternatively, the base  550  can have a different design than that illustrated in  FIG. 5B . For example, in one embodiment, the base  550  can be substantially completely circle-shaped. 
     Additionally,  FIG. 5B  further illustrates the general shape of the outer surface  538  of the sleeve  552  of the grommet  514 . For example, in one embodiment, the outer surface  538  of the sleeve  552  can be substantially cylinder-shaped or frustum-shaped, and can include one or more anti-rotation features  540  positioned about the outer surface  538  so as to inhibit relative rotation between the grommet  514  and the bone, e.g., the metatarsal  18  (illustrated in  FIG. 1A ), into which the surgical implant  212  and the grommet  514  are inserted. In certain embodiments, the anti-rotation features  540  can include one or more anti-rotation ribs that extend away from the rest of the outer surface  538  of the sleeve  552  and/or one or more anti-rotation grooves that are formed into the outer surface  538  of the sleeve  552 . Alternatively, the anti-rotation features  540  can have a different design. Still alternatively, the outer surface  538  of the sleeve  552  can be another suitable design or shape. 
     Further,  FIG. 5B  also illustrates that the inner surface  546  of the grommet  514 , i.e. the inner surface  546  of the base  550  and/or the sleeve  552  of the grommet  514  can again have a non-circular shape that inhibits any relative rotation between the grommet  514  and the outer surface of the proximal stem  224 . Moreover, the shape of the inner surface  546  can be designed to match the shape of the outer surface of the proximal stem  224 . For example, the inner surface  546  can be substantially rectangle-shaped, with rounded corners. Alternatively, the inner surface  546  can have another suitable non-circular shape, e.g., square, oval, triangle, hexagon, or other suitable shape. 
       FIG. 5C  is a side view of the grommet  514  of  FIG. 5A . In this embodiment, the outer surface  538  of the sleeve  552  again tapers slightly as the sleeve  552  extends away from the base  550  of the grommet  514 . Additionally,  FIG. 5C  further illustrates an inner taper angle  558  of the inner surface  546  (illustrated in phantom) of the sleeve  552  as the sleeve  552  extends away from the base  550 . The inner taper angle  558  largely follows the taper of the corresponding stem, e.g., the proximal stem  224  illustrated in  FIG. 2A , about which the grommet  514  is positioned. In certain embodiments, the inner taper angle  558  can be between approximately  6 . 0  and 11.0 degrees. For example, in some non-exclusive alternative embodiments, the inner taper angle  558  can be approximately, 6.0, 6.5, 7.0, 7.5, 8.0, 8.5, 9.0, 9.5, 10.0, 10.5 or 11.0 degrees. Alternatively, the inner taper angle  558  can be greater than 11.0 degrees, less than 6.0 degrees, or some other value between 6.0 and 11.0 degrees. 
       FIG. 5D  is a sectional view of the grommet  514  taken on line D-D in  FIG. 5B . In particular,  FIG. 5D  illustrates certain additional details and features of the grommet  514  illustrated in  FIG. 5A . For example,  FIG. 5D  illustrates a depth  560  of the grommet  514  from the base  550  to the end of the sleeve  552  away from the base  550 . In certain embodiments, the depth  560  of the grommet  514  can be between approximately 0.12 inches and 0.22 inches. For example, in certain non-exclusive alternative embodiments, the depth  560  of the grommet  514  can be approximately 0.12, 0.14, 0.16, 0.18, 0.20 or 0.22 inches. Alternatively, the depth  560  can be greater than 0.22 inches, less than 0.12 inches, or some other value between 0.12 and 0.22 inches. 
     Additionally,  FIG. 5D  further illustrates that the grommet  514  has grommet angle  564  that is designed to correspond to the angle of the proximal stem  224  (illustrated in  FIG. 2A ) relative to the distal stem  226  (illustrated in  FIG. 2A ). More particularly, as noted above, in certain embodiments, the proximal stem  224  is angled slightly in the upward direction relative to the distal stem  226  to correspond with the relative angling of the bones, e.g., the metatarsal  18  and the proximal phalanx  20  illustrated in  FIG. 1A , when the foot  10  (illustrated in  FIG. 1A ) is in a relaxed position. In such embodiments, the grommet angle  564  can be designed to correspond to relative angle between the proximal stem  224  and the distal stem  226 . In some embodiments, the grommet angle  564  can be between approximately 70.0 and 80.0 degrees. For example, in certain non-exclusive alternative embodiments, the grommet angle  564  can be approximately, 70.0, 72.0, 74.0, 75.0, 76.0, 78.0, or 80.0 degrees. Alternatively, the grommet angle  564  can be greater than 80.0 degrees, less than 70.0 degrees, or some other value between 70.0 and 80.0 degrees. 
       FIG. 5E  is another sectional view of the grommet  514  taken on line E-E in  FIG. 5B . In particular,  FIG. 5E  illustrates an outer taper angle  562  of the outer surface  538  of the sleeve  552  as the sleeve  552  extends away from the base  550 . In certain embodiments, the outer taper angle  562  can be between approximately 15.0 and 25.0 degrees. For example, in some non-exclusive alternative embodiments, the outer taper angle  562  can be approximately, 15.0, 17.0, 19.0, 20.0, 21.0, 23.0 or 25.0 degrees. Alternatively, the outer taper angle  562  can be greater than 25.0 degrees, less than 15.0 degrees, or some other value between 15.0 and 25.0 degrees. 
       FIG. 6  is a simplified side view of an embodiment of a cannulated tapered drill bit  666  that can be used with the present invention. In particular,  FIG. 6  illustrates a drill bit  666  that can be used to prepare the bone, e.g., the metatarsal  18  (illustrated in  FIG. 1A ) and/or the proximal phalanx  20  (illustrated in  FIG. 1A ), as necessary for insertion of a surgical implant, e.g., the surgical implant  212  illustrated in  FIG. 2A . Additionally, the drill bit  666  can be used to prepare the bone  18 ,  20  for such a surgical implant  212  that includes a pair of grommets  214 A,  214 B (illustrated in  FIG. 2A ) provided therewith. 
     As illustrated in this embodiment, the drill bit  666  includes a bit shaft  668 , and a bit head  670  that is secured to and/or integrally formed with the bit shaft  668 . The bit shaft  668  can be substantially cylindrical in shape and can be selectively positioned within a drill (not illustrated) during use. Additionally, the bit head  670  can be sized and shaped as necessary to properly prepare the bone  18 ,  20  to receive the surgical implant  212 . 
       FIG. 7  is a simplified side view of another embodiment of a cannulated tapered drill bit  766  that can be used with the present invention. In particular, similar to the previous embodiment,  FIG. 7  illustrates a drill bit  766  that can be used to prepare the bone, e.g., the metatarsal  18  (illustrated in  FIG. 1A ) and/or the proximal phalanx  20  (illustrated in  FIG. 1A ), as necessary for insertion of a surgical implant, e.g., the surgical implant  212  illustrated in  FIG. 2A . Additionally, the drill bit  766  can be used to prepare the bone  18 ,  20  for such a surgical implant  212  that includes a pair of grommets  214 A,  214 B (illustrated in  FIG. 2A ) provided therewith. 
     The design of the drill bit  766  is somewhat similar to the drill bit  666  illustrated and described in relation to  FIG. 6 . For example, the drill bit  766  again includes a bit shaft  768 , and a bit head  770  that is secured to and/or integrally formed with the bit shaft  768 . The bit shaft  768  can be substantially cylindrical in shape and can be selectively positioned within a drill (not illustrated) during use. Additionally, the bit head  770  can be sized and shaped as necessary to properly prepare the bone  18 ,  20  to receive the surgical implant  212 . As illustrated in this embodiment, the bit head  770  is somewhat larger, i.e. wider and/or longer, than the bit head  670  in the previous embodiment. 
       FIG. 8  is a simplified side view of a wire  872  that can be used with the drill bits  666 ,  766  of  FIGS. 6 and 7 . In particular, the wire  344  can be used to guide the drill bits  666 ,  766  during preparation of the bone, e.g., the metatarsal  18  (illustrated in  FIG. 1A ) and/or the proximal phalanx  20  (illustrated in  FIG. 1A ), for insertion of the surgical implant  212  (illustrated in  FIG. 2A ). 
     While a number of exemplary aspects and embodiments of a grommet  14 A,  14 B for use with a surgical implant  12  have been shown and disclosed herein above, those of skill in the art will recognize certain modifications, permutations, additions and sub-combinations thereof. It is therefore intended that the grommet  14 A,  14 B shall be interpreted to include all such modifications, permutations, additions and sub-combinations as are within their true spirit and scope, and no limitations are intended to the details of construction or design herein shown.