Patent Abstract:
A system locates a femoral cutting guide on a distal end of a femur. The femoral cutting guide establishes at least a first reference plane to perform a distal femoral planar cut. The system generally includes a mounting rod operable to insert into the distal end of the femur. An index member is operable to abut the distal end of the femur. A bridge member extends from the index member. A cutting guide member extends from the bridge member. The cutting guide member includes a first channel that establishes the first reference plane. A mounting mechanism releasably couples the cutting guide member to the bridge member. The mounting mechanism is operable to generate a sliding resistance between the bridge member and the cutting guide member that is generally overcome to position the cutting guide member relative to the femur.

Full Description:
FIELD 
       [0001]    The present teachings relate to a cutting guide for resecting a portion of a bone and more particularly relate to a distal femoral cutting guide that can be selectively adjusted over a medial anterior portion of a distal end of a femur. 
       BACKGROUND 
       [0002]    A human joint  10  is the junction of four bones: a femur  12 , a tibia  14 , a fibula  16  and a patella  18 , as shown in  FIGS. 1-3 . Myriad medical problems can require partial or complete replacement of one or more portions of the aforesaid bones that form the knee joint  10 . When using one or more prosthetic devices to replace one or more portions of the bones of the knee joint  10 , preparation portions of the various bones can be necessary to supply a proper fit for the prosthetic. Preparation can include resection or fashioning of the bones to complement an interior portion of a prosthetic. 
         [0003]    When implanting a prosthetic on a distal end  20  of the femur  12 , portions of the distal end  20  can be resected to provide a proper fit for the prosthetic. For example, a lateral condyle  22  and a medial condyle  24  can be partially or completely resected in preparation for implantation of the prosthetic. A distal femoral planar cut is generally performed relative to a mechanical angle of the knee joint  10 . To vary the angle of the distal femoral planar cut, multiple components typically have to be disassembled and reassembled to provide the proper angle. One or more of the components used to provide the distal femoral planar cut are typically positioned above an anterior surface of the femur. In such a position, access to an anterior portion of the femur and positioning components in the same area can be relatively difficult. While the above methods and components remain useful for their intended purpose, there remains room in the art for improvement. 
       SUMMARY 
       [0004]    The present teachings generally include a system that locates a femoral cutting guide on a distal end of a femur. The femoral cutting guide establishes at least a first reference plane to perform a distal femoral planar cut. The system generally includes a mounting rod operable to insert into the distal end of the femur. An index member is operable to abut the distal end of the femur. A bridge member extends from the index member. A cutting guide member extends from the bridge member. The cutting guide member includes a first channel that establishes the first reference plane. A mounting mechanism releasably couples the cutting guide member to the bridge member. The mounting mechanism is operable to generate a sliding resistance between the bridge member and the cutting guide member that is generally overcome to position the cutting guide member relative to the femur. 
         [0005]    Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present teachings. 
     
    
     
       DRAWINGS 
         [0006]    The drawings described herein are for illustration purposes only and do not limit the scope of the present teachings. 
           [0007]      FIG. 1  is a prior art partial front view of a knee joint showing bones, muscle tissue and connective tissue of the knee joint. 
           [0008]      FIG. 2  is a prior art similar to  FIG. 1  and shows a patella, the muscles and the associated connective tissue pulled away from respective portions of the knee joint. 
           [0009]      FIG. 3  is a perspective view of the knee joint, absent the muscle and the connective tissue, showing a lateral condyle, a medial condyle and an exemplary plane of resection of a distal end of the femur in accordance with the present teachings. 
           [0010]      FIG. 4  is an exploded assembly view of a distal femoral cutting guide assembly constructed in accordance with the present teachings having an index member, a bridge member and a guide member that can couple to an intramedullary rod with a bushing coupled to the index member. 
           [0011]      FIG. 5A  is a partial perspective view of the bushing installed in the index member and disposed over the intramedullary rod of  FIG. 4  that is installed on the left femur in accordance with the present teachings. 
           [0012]      FIG. 5B  is similar to  FIG. 5A  and shows the bridge member connected to the index member and receiving the guide member to hold the guide member so that the cutting guide member can be further secured to the bone with suitable fixation pins in a first set of apertures in accordance with the present teachings. 
           [0013]      FIG. 5C  is similar to  FIG. 5A  and shows the cutting guide member secured to the femur with two fixation pins in the first set of apertures. 
           [0014]      FIG. 5D  is similar to  FIG. 5C  and shows the cutting guide member pulled off the fixation pins and the femur without the need to remove the fixation pins from the left femur. 
           [0015]      FIG. 5E  is similar to  FIG. 5C  and shows the cutting guide member placed on the fixation pins that are received by additional apertures in the second set of apertures that position the cutting guide member in a superior direction, i.e., up the left femur. 
           [0016]      FIG. 5F  is similar to  FIG. 5E  and shows the cutting guide member secured to the femur with the fixation pins through a second set and a third set of fixation apertures that can hold the cutting guide member to the femur, while an exemplary resecting tool can make a cut using the guide channels that establish a reference plane on which the resection can be based. 
           [0017]      FIG. 6  is a perspective view of the distal femoral cutting guide assembly showing the distal femoral cutting guide assembly installed on a right femur in accordance with the present teachings. 
           [0018]      FIGS. 7A ,  7 B and  7 C are each front views of different bushings showing the angle at which an intramedullary rod that can be received within the bushing would be disposed relative to the index member. 
       
    
    
     DETAILED DESCRIPTION 
       [0019]    The following description is merely exemplary in nature and is not intended to limit the present teachings, their application, or uses. It should be understood that throughout the drawings, corresponding reference numerals can indicate like or corresponding parts and features. 
         [0020]    The present teachings generally include a cutting guide assembly  100  for resecting a portion of a bone, as shown in  FIG. 4 . While the various illustrated aspects of the present teachings pertain to the knee joint  10  ( FIG. 3 ) of the human body, it will be appreciated in light of the disclosure that the teachings may also be applicable to various bones of the human body including, but not limited to, the tibia, the fibula, the humerus, the ulna or the radius. It will also be appreciated that the teachings may be applicable to various bones of other animals, mammalian or otherwise, requiring replacement with prosthetics due to various medical concerns. 
         [0021]    With reference to  FIG. 4 , the cutting guide assembly  100  can include an index member  102 , a bridge member  104  and a cutting guide member  106 . The cutting guide assembly  100  can be used in a procedure to resect (i.e., surgically remove part of an organ or a structure) one or more portions of a distal end of a right femur  12   a  ( FIG. 6 ) and/or a left femur  12   b  ( FIGS. 5A-5E ), which can be collectively referred to as the distal end  20  of the femur  12 . As shown in  FIG. 5A , the index member  102  can abut the distal end  20  of the femur  12 . As shown in  FIG. 5B , the bridge member  104  can couple the cutting guide member  106  to the index member  102  and can establish a reference plane  108  (an imaginary plane, as shown in  FIG. 4 ) that can project through the distal end  20  of the femur  12 . While the bridge member  104  is shown as a separate component, in one example, the bridge member  104  and the cutting guide member  106  can be a single monolithic member or a collection of multiple components. 
         [0022]    In accordance with various aspects of the present teachings and with reference to  FIG. 6 , the cutting guide member  106  can be configured to be located over a medial anterior corner of the distal end of a right femur  12   a.  Moreover, the bridge member  104  can be configured to hold the cutting guide member  106  over the medial anterior portion of the distal end  20  of the femur  12 . While holding the cutting guide member  106 , the bridge member  104  can be configured to provide a sliding resistance between the cutting guide member  106  and the bridge member  104  in various aspects of the present teachings. The sliding resistance can be overcome by the medical professional as he or she repositions the cutting guide member  106  relative to the bridge member  104 , which will be discussed in further detail herein. 
         [0023]    In accordance with one aspect of the present teachings and with reference to  FIGS. 4 and 5A , the index member  102  can be coupled to an intramedullary rod  110  or other suitable mounting rod that can be inserted into the distal end  20  of the left femur  12   b:  A first bushing  112   a  can be selected from a plurality of bushings  112 , examples of which are shown in  FIGS. 7A ,  7 B and  7 C. Each of the bushings  112  can couple to the index member  102  and can receive the intramedullary rod  110 . Each of the bushings  112  can be configured to hold the index member  102  at a predetermined angle relative to a longitudinal axis  114  of the intramedullary rod  110 , as discussed in greater detail. 
         [0024]    With reference to  FIGS. 7A ,  7 B and  7 C, the plurality of bushings  112  can, therefore, have varying configurations that provide for holding the index member  102  at a range of angles relative to the longitudinal axis  114  of the intramedullary rod  110  and, thus, the longitudinal axis  28  of the femur  12  ( FIG. 3 ). The range of angles provided, for example, can include about four degrees to about seven degrees with about one degree angle increments between four and seven degrees. It will be appreciated that other configurations that provide more or less angle increments and/or the size of the increment can be implemented as applicable. 
         [0025]    Returning to  FIG. 4 , the index member  102  can have a first surface portion  116  that can abut the distal end  20  of the femur  12  that can include one or more portions of the medial condyle  24  and the lateral condyle  22 . A second surface portion  118  ( FIG. 6 ) can be opposite the first surface portion  116  and one or more wall portions  120  can bound the first surface portion  116  and the second surface portion  118 . The wall portions  120  can be configured in a shape that can be similar to a parallelogram, i.e., a quadrilateral with opposite sides parallel or something similar thereto. Notwithstanding, it will be appreciated in light of the disclosure that the index member  102  can be configured with various suitable polygonal shapes. Moreover, the wall portions  120  can further include connection to and/or be integrally formed with additional surfaces, facets, rounded portions, other suitable configurations and combinations thereof, that can be used to facilitate manipulation and insertion of the index member  102  through the incision  30  and/or a cannula. 
         [0026]    The index member  102  can define a bushing receiving aperture  122 . The bushing receiving aperture  122  can include wall portions  124  that can be configured to abut one of the bushings  112 . Each of the bushings  112  can releasably couple to the index member  102  and/or can lock with the various suitable locking mechanisms thereto. One or more of the suitable locking mechanisms can securely hold one of the bushings  112  to the index member  102  but then can be uncoupled as needed. 
         [0027]    The index member  102  can define one or more holes  126  that can receive one or more complementary posts  128  that can extend from the bridge member  104 . The one or more of the holes  126  can be defined in the one or more wall portions  120  of the index member  102  and can be sized with different diameters or widths, as applicable, to receive the one or more complementary posts  128  on the bridge member  104 . For example, a first post  128   a  can be received by a first hole  126   a  and, similarly, a second post  128   b  can be received by a second hole  126   b.  The first hole  126   a  and the first post  128   a  can have larger but complimentary diameters or width than the second post  128   b  and the second hole  126   b  that can have smaller but complementary diameters or widths, as applicable. 
         [0028]    The combination of the holes  126  and the complementary posts  128  can be configured such that only a single orientation can exist in which the bridge member  104  can couple to the index member  102 . In one example, as shown in  FIG. 5B , the index member  102  can be oriented in a first position that can abut the distal end of the left femur  12   b.  With reference to  FIG. 6 , the index member  102  can be re-oriented so that the index member  102  is oriented in a second position and can abut the distal end of the right femur  12   a.  The bridge member  104  can also have a first orientation ( FIG. 5B ) and a second orientation ( FIG. 6 ). With reference to  FIG. 5B , the index member  102  that can abut the left femur  12   b  can be configured to only accept the bridge member  104  in the first orientation. With reference to  FIG. 6 , the index member  102  that can abut the right femur  12   a  can be configured to only accept the bridge member  104  in the second orientation. 
         [0029]    Returning to  FIG. 4 , the bridge member  104  can define a first guide assembly  130  and a second guide assembly  132 . The first guide assembly  130  can include a channel  134  that can be operable to receive and/or releasably couple a portion of the cutting guide member  106 . One or more mounting mechanisms  136  can be mounted on one or more wall portions  138  within the channel  134  and can releasably couple the cutting guide member  106  to the first guide assembly  130 . The one or more mounting mechanisms  136  can define one or more magnets, hook and loop fasteners, suitable adhesives and/or one or more suitable combinations thereof. It will be appreciated that one or more other mechanisms can be used to releasably couple the cutting guide member  106  to the one or more wall portions  138  of the first guide assembly  130 . The one or more mounting mechanisms  136  and/or other suitable mechanisms can be made of, wholly or partially, one or more suitable biocompatible materials that can be sterilized. 
         [0030]    The second guide assembly  132  can be similar to the first guide assembly  130  but can be positioned on an opposite side of the bridge member  104 . The second guide assembly  132  can similarly include one or more mounting mechanisms  140  that can releasably couple the cutting guide member  106  to the bridge member  104 . The one or more mounting mechanisms  140  and/or one or more other suitable fastening mechanisms can be mounted on one or more wall portions  142  in the second guide assembly  132  but at a location in the second guide assembly that can be opposite of a location of the one or more mounting mechanisms  136  in the first guide assembly  130 . 
         [0031]    With reference to  FIG. 6 , the one or more mounting mechanisms  136 ,  140  in the first and the second guide assemblies  130 , 132  can hold the cutting guide member  106 , while the cutting guide member  106  can be adjusted relative to the distal end  20  of the femur  12   a,    12   b.  After final adjustment, the cutting guide member  106  can be held by the bridge member  104  until a relatively more secure fastener can couple to the cutting guide member  106  to the femur  12   a,    12   b,  an example of which is shown in  FIG. 5F . During one or more adjustments, the mounting mechanisms  136 ,  140  can provide for a sliding resistance that can be overcome by a medical professional (not shown) when he or she repositions (i.e., the one or more adjustments) the cutting guide member  106  relative to the bridge member  104  and/or relative to the distal end  20  of the femur  12   a,    12   b.    
         [0032]    Returning to  FIG. 4 , the cutting guide member  106  can generally define a body portion  142  having a first guide channel portion  144  and a second guide channel portion  146  that can be formed through the body portion  142  and can be spaced from one another. The first and the second channel portions  144 ,  146  can each define a generally elongated rectangular aperture through which a suitable tool  148  ( FIG. 5F ), such as a manual or a powered resecting tool, can be placed for cutting a portion of the distal end  20  of the femur  12 , as shown in  FIG. 5C . One or more wall portions  152  of the first guide channel portions  144  can establish the first reference plane  154  on which a resection of the medial anterior portion  150  of the femur  12  can be preformed. In addition, the one or more wall portions  156  of the second guide channel  146  can establish a second reference plane  158 . 
         [0033]    The body portion  142  of the cutting guide member  106  can define a generally arcuate shape. The generally arcuate shape can be configured to fit over a medial anterior portion  150  of the femur  12   a,    12   b.  It will be appreciated in light of the disclosure the arcuate shape can be configured to be disposed over a medial surface and an anterior surface of the distal end  20  of the femur  12 . In this position, the arcuate shape of the cutting guide member  106  can be disposed over a portion of the medial anterior corner of the femur  12 . 
         [0034]    The first cutting channel  144  and the second cutting channel  146  can be configured with a similar size and/or shape but can be spaced from one another a predetermined distance  160 . In one example, the predetermined distance  160  can be sufficient enough to provide about a three millimeter difference in a distal cutting depth  162  ( FIG. 5C ) between a resection based on the first reference plane  154  and a resection based on the second reference plane  158 . By way of the above example, the medical professional can resect a portion of the femur  12  by placing the suitable resecting tool  148  through the first guide channel  144 . The resecting tool  148  ( FIG. 5F ) can also cut an additional three millimeters from the femur  12   a,    12   b  by placing the resecting tool  148  through the second guide channel  146  and cutting the distal end  20  of the femur  12   a,    12   b  based on the second reference plane  158  established by the second guide channel  146 . 
         [0035]    The body portion  142  of the cutting guide member  106  can include a plurality of apertures  164 . Each of the apertures  164  can receive one or more fixation pins  166 . The plurality of apertures  164  can include at least a first set of apertures  164   a,  a second set of apertures  164   b  and a third set of apertures  164   c.  With the cutting guide member  106  secured to the femur  12   a,    12   b  with the fixation pins  166  either in the first set of apertures  164   a  or in the second set of apertures  164   b,  the cutting guide member  106  can still be removed from the femur  12  without the need to remove the fixation pins  166 . In this regard, the first set of apertures  164   a  and the second set of apertures  164   b  are configured so as to permit the cutting guide member  106  to be lifted off the femur  12   a,    12   b  with the fixation pins  166  remaining, as shown, for example, in  FIG. 5D . 
         [0036]    In contrast, the third set of apertures  164   c  are configured such that when the cutting guide member  106  is fixed to the femur  12  using the third set of apertures  164   c,  the cutting guide member  106  can only be removed from the femur  12   a,    12   b  by removing the fixation pins  166  from the third set of apertures  164   c.  As such, securing the cutting guide member  106  to the femur  12   a,    12   b  with the third set of apertures  164   c  ( FIG. 5F ) relative to the first set of apertures  164   a  ( FIG. 5C ) can be shown to provide a relatively more robust securement during a resection procedure. The fixation pins  166 , however, need to be removed from the third set of apertures  164   c  before the cutting guide member  106  can be removed from the femur  12 . 
         [0037]    In one example, when one or more of the fixation pins  166  are in the first set of apertures  164   a,  the fixation pins  166  are disposed generally normal to an exterior surface  168  of the femur  12   a,    12   b.  Because the fixation pins  166  are generally normal to the exterior surface  168 , the cutting guide member  106  can be secured from rotation and/or displacement in directions that are generally parallel to the longitudinal axis  114  ( FIG. 6 ) of the femur  12   a,    12   b.    
         [0038]    The cutting guide member  106 , however, can be pulled away from the exterior surface  168  of the femur  12   a,    12   b  so that the cutting guide member  106  can be, for example, repositioned. In this regard, the cutting guide member  106  can be advanced up (i.e., in a superior direction) or down (i.e., in an inferior direction) relative to the longitudinal axis  114  of the femur  12  to adjust the reference planes  154 ,  158  for a more deep or a more shallow resection of the distal end  20  of the femur  12  (see, e.g.,  FIGS. 5C ,  5 D,  5 E and  5 F). In doing so, the first set of apertures  164   a  can release the fixation pins  166  and the second set of apertures  164   b  can receive the fixation pins  166  so that the cutting guide member  106  can be located in a more superior position. In contrast, the third set of apertures  164   c  in the cutting guide member  106  can be at an angle  169  ( FIG. 5D ) that, in certain aspects, is not parallel to the first and second set of apertures  164   a,    164   b.  The configuration of the angle  169  allows the cutting guide member  106  to be relatively more securely fastened to the femur  12   a,    12   b  in that the cutting guide member  106  may not lift off the femur  12   a,    12   b,  while the fixation pins  166  are received by the third set of apertures  164   c.    
         [0039]    With reference to  FIG. 5F , the suitable resecting tool  148  can be manual or powered. A powered implementation of the resecting tool  148  can be electrical and/or pneumatic. A portion of the resecting tool  148 , for example, a blade  172  can index off (e.g., abut while reciprocating) one of the first cutting channel  144  or the second cutting channel  146  formed in the cutting guide member  106 . In this regard, the resecting tool  148  can cut along (or cut generally parallel to) the reference plane  154  established by the first cutting channel  144  or the second reference plane  158  established by the second cutting channel  146 . 
         [0040]    With reference to  FIG. 5A , the intramedullary rod  110  can be configured to fit into an intramedullary canal  176 . In one example, the intramedullary rod  110  can be inserted in a hole i  78  formed between the condyles  22 ,  24  of the distal end  20  of the femur  12 . It will be appreciated in light of the disclosure that the intramedullary rod  110  can be inserted in the hole  178 , a sufficient distance so that various components can be installed on an end of the intramedullary rod  110  that is not disposed in the intramedullary canal  176 . A portion of the intramedullary rod  110  can be configured to accept a removable handle  180  that can be used to facilitate installation and/or removal of the intramedullary rod  110  in and from the intramedullary canal  176  and/or to facilitate installation or removal of various components on and from the intramedullary rod  110 . 
         [0041]    With reference to  FIG. 4A , a cross-section  182  of the intramedullary rod  110  can be generally oval but can include one or more portions that can be removed from an otherwise whole oval-shape. In one example, two v-shaped grooves  184  can be formed at generally opposite sides of the intramedullary rod  110 . The v-shaped grooves  184  or other suitable portions removed from the intramedullary rod  110  can provide for an anti-rotation functionality. In this regard, one or more components that can be inserted on the intramedullary rod  110  can be keyed (i.e., include key to interconnect with one of the grooves  184 ) to provide an anti-rotation functionality. 
         [0042]    The various components of the cutting guide assembly  100  can be made of one or more suitable bio-compatible materials. One example of a bio-compatible material is a cobalt chrome alloy. Other examples can include titanium and suitable polymers such as an ultra high molecular weight polyethylene. 
         [0043]    With reference to  FIGS. 4 ,  7 A,  7 B,  7 C, the bushing  112  can couple the intramedullary rod  110  to the index member  102 . The bushing  112  can be configured such that the intramedullary rod  110  can be held at the angle  170  relative to the index member  102 . In this regard, the angle  170  can range from negative four to positive four degrees. As explained above, one bushing  112   a  can be selected from the plurality of bushings  112  to select a predetermined angle between the intramedullary rod  110  and the index member  102 . As such, each bushing  112  of the plurality of bushings  112  can be configured to provide a different angle between the longitudinal axis  114  of the intramedullary rod  110  and the index member  102 . 
         [0044]    In operation, one or more incisions  30  can be made near the knee joint  10  to provide access to a portion of the distal end  20  of the femur  12 , as shown in  FIG. 3 . With reference to  FIGS. 4-5F , the intramedullary rod  110  can be mounted into the hole  178  ( FIG. 5C ) formed in the distal end  20  of the femur  12 . The handle  180  can be removed from the intramedullary rod  110  to provide access and to allow for components to be inserted over the intramedullary rod  110 . One of the bushings  112  can be selected from the plurality of bushings  112  ( FIGS. 7A-7C ) to establish, for example, the reference plane  108 ,  154 ,  158  that is disposed at the angle  170  ( FIGS. 7A-7C ) relative to the longitudinal axis  114  of the intramedullary rod  1   10 . The angle  170  can be a suitable valgus angle as determined by the medical practitioner. 
         [0045]    When one of the proper bushings  112  is selected, the bushing  112  can be coupled to the index member  102 . The bridge member  104  can be coupled to the index member  102 . The cutting guide member  106  can then be coupled to the index member  102  and held in place in the first guide assembly  130  by the one or more mounting mechanisms  140  or other suitable fasteners. The index member  102 , the bridge member  104  and the cutting guide member  106  can be inserted over the intramedullary rod  110  via the bushing  112  and slid down the intramedullary rod  110  to abut the distal end  20  of the femur  12 . 
         [0046]    When the index member  102  abuts the distal end  20  of the femur  12 , the cutting guide member  106  can be manipulated so as to be positioned around the medial anterior portion  150  of the distal end  20  of the femur  12 . In this regard, the arcuate shape of the cutting guide member  106  can be disposed around the medial anterior portion  150  of the femur  12   a,    12   b  to provide the access to that portion of the femur  12   a,    12   b.    
         [0047]    The cutting guide member  106  can be releasably coupled to the bridge member  104  so as to provide a sliding resistance between the cutting guide member  106  and the bridge member  104 . It will be appreciated in light of this disclosure that the medical professional can overcome the sliding resistance as he or she manipulates the cutting guide member  106  relative to the femur  12  as he or she positions the cutting guide member  106  about the medial anterior portion of the distal end  20  of the femur  12 . 
         [0048]    With reference to  FIG. 5F , when the cutting guide member  106  is positioned as described above, one or more of the fixation pins  166  can be driven into the first set of apertures  164   a  formed on the body portion  142  of the cutting guide member  106 . One or more additional fixation pins  166  can be inserted through the third set of apertures  164   c  formed in the body portion  142  of the cutting guide member  106 . Resection of the distal end  20  of the femur  12   a,    12   b  along the first reference plane  154  established by the first channel portion  144  can occur with the cutting guide member  106  secured to the femur  12  with the fixation pins  166  in one of the first set of apertures  164   a,  the second set of apertures  164   b,  the third set of apertures  164   c  and one or more combinations thereof. When the fixation pins  166  are received in the third set of apertures  164   c,  the fixation pins  166  can be removed so as to allow the cutting guide member  106  to be lifted off the fixation pins  166  received in the first set of apertures  164   a  and, for example, advanced up in a direction superior to the distal end  20  of the femur  12  and then re-secured by allowing the second set of apertures  164   b  to receive the same fixation pins  166 . In this regard, the cutting guide member  106  is advanced up the femur  12   a,    12   b  a predetermined distance. 
         [0049]    Prior to or after the advancement of the cutting guide member  106  of the femur  12   a,    12   b,  the medical practitioner can continue to resect the distal end  20  of the femur  12   a,    12   b  using the first cutting channel  144  or the second cutting channel  146 , which can be at a predetermined distance from the first cutting channel  144 . 
         [0050]    While specific aspects have been described in this specification and illustrated in the drawings, it will be understood by those skilled in the art in light of the disclosure that various changes can be made and equivalents can be substituted for elements thereof without departing from the scope of the present teachings, as defined in the claims. Furthermore, the mixing and matching of features, elements and/or functions between various aspects of the present teachings are expressly contemplated herein so that one skilled in the art will appreciate from the present teachings that features, elements and/or functions of one aspect of the present teachings may be incorporated into another aspect, as appropriate, unless described otherwise above. Moreover, many modifications may be made to adapt a particular situation, configuration and/or material to the present teachings without departing from the essential scope thereof. Therefore, it is intended that the present teachings not be limited to the particular aspects illustrated by the drawings and described in the specification as the best mode presently contemplated for carrying out the present teachings but that the scope of the present teachings will include many aspects and examples following within the foregoing description and the appended claims.

Technology Classification (CPC): 0