Abstract:
An osteotomy wedge according to an exemplary aspect of the present disclosure includes, among other things, an asymmetrical body that includes a perimeter established by a continuous, smooth surface. Further, the perimeter includes a concave surface.

Description:
BACKGROUND 
       [0001]    This disclosure relates to an anatomic osteotomy wedge and, in particular, an anatomic osteotomy wedge for a medial cuneiform bone. 
         [0002]    An osteotomy is a surgical operation in which a bone is cut to shorten, lengthen, or change its alignment. In some osteotomies, the bone is cut and an implant is provided in the bone to change the alignment of the bone. In a medial cuneiform osteotomy, an implant is used to correct a deformity in the foot, such as flat footedness. In some medial cuneiform osteotomies, an implant with a triangular cross-section is used to align the foot. The triangular implant is symmetrical about its centerline. 
       SUMMARY 
       [0003]    An osteotomy wedge according to an exemplary aspect of the present disclosure includes, among other things, an asymmetrical body that includes a perimeter established by a continuous, smooth surface. Further, the perimeter includes a concave surface. 
         [0004]    In a further non-limiting embodiment of the foregoing osteotomy wedge, the concave surface is a plantar-lateral surface of the body. 
         [0005]    In a further non-limiting embodiment of the foregoing osteotomy wedge, the body includes a fore surface and a hind surface, the fore surface and the hind surface each having a texture configured to engage bone. 
         [0006]    In a further non-limiting embodiment of the foregoing osteotomy wedge, the texture includes a plurality of pyramid-shaped projections. 
         [0007]    In a further non-limiting embodiment of the foregoing osteotomy wedge, a dorsal surface of the body provides a threaded opening. 
         [0008]    In a further non-limiting embodiment of the foregoing osteotomy wedge, a central axis of the threaded opening is angled at a non-perpendicular angle relative to a plane provided by a dorsal surface of the body. 
         [0009]    In a further non-limiting embodiment of the foregoing osteotomy wedge, the central axis intersects the plane. 
         [0010]    In a further non-limiting embodiment of the foregoing osteotomy wedge, the body is made of a porous metal. 
         [0011]    In a further non-limiting embodiment of the foregoing osteotomy wedge, the metal foam is a titanium-based porous metal. 
         [0012]    An osteotomy wedge according to another exemplary aspect of the present disclosure includes, among other things, a body having a dorsal surface having a threaded opening. A central axis of the threaded opening is angled at a non-perpendicular angle relative to a plane provided by the dorsal surface of the body. 
         [0013]    In a further non-limiting embodiment of the foregoing osteotomy wedge, the central axis intersects the plane. 
         [0014]    In a further non-limiting embodiment of the foregoing osteotomy wedge, the body includes a perimeter provided by a continuous, smooth surface, the perimeter including a concave surface. 
         [0015]    In a further non-limiting embodiment of the foregoing osteotomy wedge, the concave surface is a plantar-lateral surface of the body. 
         [0016]    In a further non-limiting embodiment of the foregoing osteotomy wedge, the body includes a fore surface and an hind surface, the fore surface and the hind surface each having a texture configured to engage bone. 
         [0017]    In a further non-limiting embodiment of the foregoing osteotomy wedge, the texture includes a plurality of pyramid-shaped projections. 
         [0018]    An osteotomy wedge assembly according to an exemplary aspect of the present disclosure includes, among other things, an osteotomy wedge provided by a body, the body having a dorsal surface which provides a threaded opening. The assembly includes a fastener having a threaded shaft received in the threaded opening, and a plate secured to the osteotomy wedge by the fastener. A central axis of the threaded shaft is angled at a non-parallel angle relative to a plane provided by a surface of the plate. 
         [0019]    In a further non-limiting embodiment of the foregoing assembly, a head of the fastener is angled at a non-perpendicular angle relative to a central axis of the threaded shaft. 
         [0020]    In a further non-limiting embodiment of the foregoing assembly, the plate is generally rectangular and includes openings for receiving fasteners. 
         [0021]    In a further non-limiting embodiment of the foregoing assembly, the plate includes four exaggerated corners, each of the exaggerated corners including a respective opening. 
         [0022]    In a further non-limiting embodiment of the foregoing assembly, the plate is generally rectangular and includes two openings at each end thereof. 
         [0023]    The embodiments, examples and alternatives of the preceding paragraphs, the claims, or the following description and drawings, including any of their various aspects or respective individual features, may be taken independently or in any combination. Features described in connection with one embodiment are applicable to all embodiments, unless such features are incompatible. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0024]    The drawings can be briefly described as follows: 
           [0025]      FIG. 1  is a top view of a foot including an osteotomy wedge. 
           [0026]      FIG. 2A  is a view of the osteotomy wedge of  FIG. 1  from a forefoot direction. 
           [0027]      FIG. 2B  is a close-up view illustrating the texture of a fore surface of the osteotomy wedge of  FIG. 2A . 
           [0028]      FIG. 3  is a top view of the osteotomy wedge of  FIG. 2A . 
           [0029]      FIG. 4  is a side view of the osteotomy wedge of  FIG. 2A . 
           [0030]      FIG. 5  is a view taken along line  5 - 5  from  FIG. 1 , and illustrates the arrangement of the osteotomy wedge relative to the medial cuneiform bone. 
           [0031]      FIG. 6  illustrates an instrument used with the osteotomy wedge of  FIG. 1 . 
           [0032]      FIG. 7A  illustrates an osteotomy wedge assembly including a cover plate and the osteotomy wedge of  FIG. 1 . 
           [0033]      FIG. 7B  is a top view of a first example cover plate. 
           [0034]      FIG. 7C  is a top view of a second example cover plate. 
       
    
    
     DETAILED DESCRIPTION 
       [0035]      FIG. 1  illustrates the bones of a foot  20  from a top (dorsal) perspective. The foot  20  includes a forefoot  22 , a midfoot  24 , and a hindfoot  26 . The midfoot  24  includes a medial cuneiform bone  28 . An inner cuneiform bone  30  is located on a lateral side of the medial cuneiform bone  28 . The interface between the medial cuneiform and inner cuneiform bones  28 ,  30  is referred to as an intercuneiform joint  31 . As illustrated, an osteotomy wedge  32  has been implanted into the medial cuneiform bone  28  to correct deformities of the foot  20 . The osteotomy wedge  32  may have uses beyond the medial cuneiform bone  28 . 
         [0036]      FIG. 2A  illustrates the detail of the osteotomy wedge  32  from a forefoot perspective. For purposes of illustration,  FIGS. 3 and 4  show the same osteotomy wedge  32  from a top (dorsal) view and a side (medial) view, respectively. 
         [0037]    The osteotomy wedge  32  includes a continuous, uninterrupted body  33  in this example. Further, the body  33  has an asymmetrical shape. That is, when viewed from the forefoot or hindfoot directions, it is not possible to draw an axis through a center of mass M of the body  33  such that the body  33  would be symmetrical about that axis. 
         [0038]      FIG. 2A  includes a partial sectional view at area A, which illustrates a threaded opening  34  in a dorsal surface  36  of the osteotomy wedge  32 . In this example, the threaded opening  34  has a centerline C that is angled at a non-perpendicular angle (when viewed from the forefoot or hindfoot directions) relative to a plane P provided by the dorsal surface  36 . This angle increases the ease of implanting the osteotomy wedge  32  into the medial cuneiform bone  28 . In particular, the osteotomy wedge  32  can be more easily maneuvered when attached to an insertion instrument, such as the instrument  62  of  FIG. 6 . 
         [0039]    With the exception of the threaded opening  34 , the perimeter of the osteotomy wedge  32  is a continuous, uninterrupted surface. Moving clockwise from the dorsal surface  36 , the perimeter of the osteotomy wedge  32  includes a first rounded corner  38 , which transitions into a convex dorsomedial surface  40 . The dorsomedial surface  40  transitions, via a second rounded corner  42 , into a plantar surface  44 , which, in turn, transitions into a plantar-lateral surface  46 , via a third rounded corner  48 . The plantar-lateral surface  46  is concave. Finally, the plantar-lateral surface  46  transitions, via a fourth rounded corner  50  into the dorsal surface  36 . 
         [0040]    While the outer perimeter of the osteotomy wedge  32  may be relatively smooth, fore and hind surfaces  52 ,  54  of the osteotomy wedge  32  may include a surface texture configured to hold the osteotomy wedge  32  in place relative to the medial cuneiform bone  28 .  FIG. 2B  is a close-up view illustrating the texture of the fore surface  52 . As illustrated in  FIG. 2B , the fore surface  52  includes a plurality of pyramid-shaped projections  56  arranged in a crisscross pattern, in this example.  FIGS. 3 and 4  also illustrate the projections  56 . It should be understood that the hind surface  54  may include the same texture as the fore surface  52 . In this example, the projections  56  are evenly distributed along the fore and hind surfaces  52 ,  54 . While a particular surface texture is illustrated, this disclosure is not limited to any particular surface texture arrangement. 
         [0041]    As illustrated in  FIG. 4 , the osteotomy wedge  32  is tapered from the dorsal surface  36  to the plantar surface  44 . That is, the thickness of the osteotomy wedge  32  continuously decreases from the dorsal surface  36  to the plantar surface  44 . For purposes of illustration, the osteotomy wedge  32  has a first thickness T 1  adjacent the dorsal surface  36 , which is greater than a second thickness T 2  adjacent the plantar surface  44 . The taper of the osteotomy wedge  32  provides the desired alignment of the medial cuneiform bone  28 . 
         [0042]    In one example, the osteotomy wedge  32  includes a central opening  57  having a contour  59  that substantially matches the contour of the perimeter of the osteotomy wedge  32 . This disclosure is not limited to any particular contour for the central opening, however. 
         [0043]    The osteotomy wedge  32  may be made of a porous metal, such as a titanium-based porous metal, in some examples. Additionally, the osteotomy wedge could be made of a PEEK (Polyether ether ketone) or a resorbable polymer material. In other examples, the osteotomy wedge includes, either in whole or in part, an allograft or xenograft. It should be understood that this disclosure is not limited to any particular material type. 
         [0044]      FIG. 5  is a sectional view taken along line  5 - 5  from  FIG. 1  and illustrates the arrangement of the osteotomy wedge  32  relative to the medial cuneiform bone  28 . As illustrated in  FIG. 5 , when implanted relative to the medial cuneiform bone  28 , the dorsomedial surface  40  of the osteotomy wedge  32  substantially follows the contour of the dorsomedial surface  58  of the medial cuneiform bone  28 . Further, the dorsomedial surface  40  of the osteotomy wedge  32  does not protrude beyond the dorsomedial surface  58  of the medial cuneiform bone  28 . The convex nature of the dorsomedial surface reduces, and ideally eliminates, prominence of the dorsomedial surface  40  beyond the dorsomedial surface  58  of the medial cuneiform  28 . This reduces, and ideally eliminates, contact between the osteotomy wedge  32  and the adjacent soft tissue of the foot, which may have otherwise caused irritation. 
         [0045]    Similarly, the contour of the plantar-lateral surface  46  of the osteotomy wedge  32  substantially follows the contour of the plantar-lateral surface  60  of the medial cuneiform bone  28 . Further, the plantar-lateral surface  46  of the osteotomy wedge  32  does not protrude beyond the plantar-lateral surface  60  of the medial cuneiform bone  28 . The concave nature of the plantar-lateral surface  46  avoids violation of the intercuneiform joint  31 , which reduces, and ideally eliminates, irritation that may have been caused by contact between the osteotomy wedge  32  and the inner cuneiform bone  30 . 
         [0046]      FIG. 6  illustrates an instrument  62  having a threaded tip  64  at a distal end thereof for insertion into the threaded opening  34  of the osteotomy wedge  32 . The instrument  62  can be used by a surgeon, for example, during surgery to insert the osteotomy wedge  32  into a cut section of the medial cuneiform bone  28 . After the osteotomy wedge  32  is implanted, the instrument  62  can be unscrewed and removed from the osteotomy wedge  32 . As noted above, the angle of the threaded opening  34  increases the ease of implanting the osteotomy wedge  32 . 
         [0047]    After removing the instrument  62 , a plate  68  may be fastened to the osteotomy wedge  32  by way of a fastener  70 . An example plate  68  and fastener  70  are illustrated in cross-section in  FIG. 7A . In this example, the fastener  70  has a threaded shaft  72  that is received in the threaded opening  34 . The threaded shaft  72  is arranged along an axis  73 , which is angled at a non-perpendicular angle relative to both a head  74  of the fastener  70  and an upper (dorsal) surface  78  of the plate  68 . In this example, the plate  68  includes a recess  76  in the upper surface  78 , which is sized such that the head  74  of the screw  70  does not project beyond the upper surface  78 . The recess  76  reduces irritation that the head  74  may have caused relative to the adjacent soft tissue of the foot. 
         [0048]    Depending on the application, the plate  68  may be fastened to the adjacent dorsal surface of the medial cuneiform bone  28 .  FIG. 7B  illustrates a first example configuration of the plate  68 ′, which includes four openings  80  for receiving fasteners, such as bone screws. The plate  68 ′ is generally rectangular with exaggerated corners. Another example plate  68 ″ ( FIG. 7C ) is generally rectangular, without the exaggerated corners of the plate  68 ′, and includes the two openings  82  for receiving fasteners. It should be understood that the plates  68 ′ and  68 ″ are examples only, and that this disclosure is not limited to any particular plate shape. For instance, this disclosure could be used with anatomically shaped plates. 
         [0049]    It should be understood that while a particular osteotomy wedge shape is illustrated in the Figures, that the osteotomy wedge  32  may be scaled up or down in size in order to fit medial cuneiform bones of different sizes. 
         [0050]    It should be understood that terms such as “fore,” “hind,” “dorsal,” “plantar,” “medial,” and “lateral” are used above with reference to the normal attitude of the human body, and in this case the foot. These terms have been used herein for purposes of explanation, and should not be considered otherwise limiting. Further, terms such as “generally” and “substantially” are not intended to be boundaryless terms, and should be interpreted consistent with the way one skilled in the art would interpret the term. 
         [0051]    Although the different examples have the specific components shown in the illustrations, embodiments of this disclosure are not limited to those particular combinations. It is possible to use some of the components or features from one of the examples in combination with features or components from another one of the examples. 
         [0052]    One of ordinary skill in this art would understand that the above-described embodiments are exemplary and non-limiting. That is, modifications of this disclosure would come within the scope of the claims. Accordingly, the following claims should be studied to determine their true scope and content.