Patent Publication Number: US-9414851-B2

Title: Patella clamp and drill guide surgical instrument and method of use

Description:
This application claims priority under 35 U.S.C. §120 to U.S. application Ser. No. 13/538,086, which was filed on Jun. 29, 2012 and claimed priority under 35 U.S.C. §119 to U.S. Provisional Application Ser. No. 61/503,419 entitled “PATELLA CLAMP AND DRILL GUIDE SURGICAL INSTRUMENT,” which was filed on Jun. 30, 2011, the entirety of each of which is incorporated herein by reference. 
     CROSS-REFERENCES TO RELATED U.S. PATENT APPLICATIONS 
     Cross-reference is made to U.S. Provisional Patent Application Ser. No. 61/503,164 entitled “PATELLA DRILL GUIDE AND CLAMP ASSEMBLY” by Abraham Wright et al., and U.S. Design Patent Application Ser. No. 29/396,511 entitled “PATELLA DRILL GUIDE AND CLAMP” by Abraham Wright et al., each of which is assigned to the same assignee as the present application, is filed concurrently herewith, and is hereby incorporated by reference. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates generally to orthopaedic surgical instruments and, more particularly, to patella surgical instruments. 
     BACKGROUND 
     Joint arthroplasty is a well-known surgical procedure by which a diseased and/or damaged natural joint is replaced by a prosthetic joint. A typical knee prosthesis includes a tibial tray, a femoral component, and a polymer insert or bearing positioned between the tibial tray and the femoral component. In some cases, the knee prosthesis may also include a prosthetic patella component, which is secured to a posterior side of the patient&#39;s surgically-prepared patella. To secure the prosthetic component to the patella, an orthopaedic surgeon may resect the posterior side of the patient&#39;s natural patella to prepare the natural patella to receive the prosthetic component. In use, the patella prosthetic component articulates with the patient&#39;s natural or prosthetic femur during extension and flexion of the patient&#39;s knee. 
     To facilitate the replacement of the natural joint with the knee prosthesis, orthopaedic surgeons use a variety of orthopaedic surgical instruments such as, for example, cutting blocks, drill guides, milling guides, and other surgical instruments. 
     SUMMARY 
     According to one aspect of the disclosure, an orthopaedic surgical instrument is disclosed. The orthopaedic surgical instrument includes a patella drill guide that has a first bracket and a second bracket moveably coupled to the first bracket, and a gasket that is removably coupled to the second bracket. The second bracket includes a drill plate having a plurality of guide holes defined therein, and the drill plate is formed from a substantially transparent material. Each of the plurality of guide holes is sized to receive a surgical drill. The gasket is configured to cover the guide holes when coupled to the second bracket. 
     In some embodiments, the first bracket may include a mounting plate. The mounting plate may have a first clamping surface with a first plurality of teeth extending therefrom. The drill plate of the second bracket may include a first clamping surface facing the first clamping surface of the mounting plate. The first clamping surface of the drill plate may have a second plurality of teeth extending therefrom. 
     In some embodiments, the first clamping surface of the mounting plate may extend substantially parallel to the first clamping surface of the drill plate. Additionally, in some embodiments, the gasket may have a first surface configured to contact the first clamping surface of the drill plate. The first surface of the gasket may have a plurality of positioning holes defined therein that are configured to receive the second plurality of teeth of the drill plate. In some embodiments, the gasket may have a concave second surface opposite the first surface. 
     In some embodiments, the first clamping surface of the drill plate may have a plurality of etch marks defined therein. Each etch mark may correspond to a size of a patient&#39;s patella. Additionally, in some embodiments, the plurality of etch marks may be arranged as a plurality of inscribed lines defined in the first clamping surface of the drill plate. In some embodiments, the drill plate may have a front surface positioned opposite the first clamping surface. Each inscribed line may be visible through the front surface. 
     In some embodiments, the mounting plate and the drill plate may be formed from a polymeric material. In some embodiments, the orthopaedic surgical instrument may include a plurality of metal bushings attached to the drill plate. Each metal bushing may define a corresponding one of the plurality of guide holes. 
     Additionally, in some embodiments, the plurality of guide holes of the drill plate may be arranged in a triangular pattern. In some embodiments, the gasket may be formed from an elastomeric material. 
     According to another aspect of the disclosure, an orthopaedic surgical instrument has a housing including a handle and a first bracket. The first bracket has a mounting plate and a plurality of teeth extending therefrom. The orthopaedic surgical instrument also includes a second bracket moveably coupled to the housing. The second bracket has a drill plate spaced apart from the mounting plate of the first bracket, and the drill plate includes a plurality of guide holes. Each of the guide holes is sized to receive a surgical drill, and a plurality of teeth extend from the drill plate toward the mounting plate. The orthopaedic surgical instrument further includes a clamp actuation mechanism coupled to the housing and the second bracket. The clamp actuation mechanism is operable to move the second bracket in a first direction toward the first bracket. 
     In some embodiments, each of the plurality of guide holes may have a longitudinal axis extending therethrough. The second bracket may include a beam moveably coupled to the housing. The beam may be configured to move relative to the housing along an axis extending parallel to the longitudinal axes of the guide holes. Additionally, in some embodiments, the clamp actuation mechanism may include an actuation plate positioned in the housing and configured to engage the beam. The actuation plate may include a follower surface. The clamp actuation mechanism may include a lever pivotally coupled to the housing such that the lever is moveable between a first position and a second position. The lever may include a cam surface configured to engage the follower surface of the actuation plate when the lever is moved from the first position to the second position such that the actuation plate engages the beam to move the second bracket along the axis in the first direction. 
     In some embodiments, the clamp actuation mechanism may include a biasing element positioned between the actuation plate and an inner wall of the housing. 
     Additionally, in some embodiments, the orthopaedic surgical instrument may further include a locking mechanism configured to selectively prevent movement of the second bracket in a second direction away from the first bracket. In some embodiments, the locking mechanism may include a locking plate moveable between a first position in which the locking plate engages the beam to prevent movement of the second bracket in the second direction, and a second position in which the locking plate is disengaged from the beam such that the second bracket is permitted to move in the second direction. The locking mechanism may include a biasing element positioned between the locking plate and the housing. The biasing element may be configured to bias the locking plate in the first position. In some embodiments, the orthopaedic surgical instrument may include a release button attached to the locking plate. 
     According to another aspect, the orthopaedic surgical instrument includes a polymeric housing including a handle and a first bracket. The first bracket may have a mounting plate and a plurality of teeth extending therefrom. The orthopaedic surgical instrument also includes a second bracket moveably coupled to the housing. The second bracket has a drill plate formed from a substantially transparent material. The drill plate includes a clamping surface, a front surface, and a plurality of guide holes extending through the clamping surface and the front surface. Each of the guide holes is sized to receive a surgical drill. A plurality of etch marks are defined in the clamping surface of the drill plate. The plurality of etch marks are visible through the front surface. The orthopaedic surgical instrument further includes a clamp actuation mechanism coupled to the polymeric housing and the second bracket and a locking mechanism coupled to the housing and the second bracket. The clamp actuation mechanism is operable to move the second bracket in a first direction toward the first bracket, and the locking mechanism is configured to selectively prevent movement of the second bracket in a second direction away from the first bracket. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The detailed description particularly refers to the following figures, in which: 
         FIG. 1  is a perspective view of an orthopaedic surgical instrument; 
         FIG. 2  is a rear elevation view of a drill plate of the orthopaedic surgical instrument of  FIG. 1 ; 
         FIG. 3  is a front elevation view of the drill plate of  FIG. 2 ; 
         FIG. 4  is a partial cutaway side elevation view of the orthopaedic surgical instrument of  FIG. 1  showing the drill plate in one position relative to a housing of the orthopaedic surgical instrument; 
         FIG. 5  is a partial cutaway side elevation view of the orthopaedic surgical instrument of  FIG. 1  showing the drill plate in another position relative to the housing; 
         FIG. 6  is a partial cutaway side elevation view similar to  FIG. 5 ; 
         FIG. 7  is a partial cutaway side elevation view similar to  FIGS. 5 and 6 ; 
         FIG. 8  is a perspective view of a compression gasket of the orthopaedic surgical instrument of  FIG. 1 ; 
         FIG. 9  is a side elevation view of the orthopaedic surgical instrument of  FIG. 1  with a patient&#39;s resected patella and a prosthetic patella component; 
         FIG. 10  is a front elevation view of the orthopaedic surgical instrument of  FIG. 1  with the patient&#39;s resected patella positioned between the drill plate and a mounting plate of the orthopaedic surgical instrument; 
         FIG. 11  is a perspective view of the orthopaedic surgical instrument of  FIG. 1  with a surgical drill; and 
         FIG. 12  is a perspective view of the orthopaedic surgical instrument of  FIG. 1  with a patella prosthetic component secured to the patient&#39;s resected patella. 
     
    
    
     DETAILED DESCRIPTION OF THE DRAWINGS 
     While the concepts of the present disclosure are susceptible to various modifications and alternative forms, specific exemplary embodiments thereof have been shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that there is no intent to limit the concepts of the present disclosure to the particular forms disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims. 
     Terms representing anatomical references, such as anterior, posterior, medial, lateral, superior, inferior, etcetera, may be used throughout the specification in reference to the orthopaedic implants and surgical instruments described herein as well as in reference to the patient&#39;s natural anatomy. Such terms have well-understood meanings in both the study of anatomy and the field of orthopaedics. Use of such anatomical reference terms in the written description and claims is intended to be consistent with their well-understood meanings unless noted otherwise. 
     Referring to  FIG. 1 , an orthopaedic surgical instrument  10  includes a patella clamp and drill guide  12  (hereinafter guide  12 ) and a compression gasket  14  configured to be secured to the guide  12 . As described in greater detail below, the instrument  10  is utilized to surgically prepare a patient&#39;s resected patella  16  (see  FIG. 9 ) for implantation of a patella prosthetic component, such as a patella prosthetic component  18  (see  FIG. 9 ). To do so, the patient&#39;s resected patella  16  may be positioned in the guide  12 , and the surgeon may use the guide  12  to drill fixation holes into the planar, resected posterior surface. The surgeon may also use the guide  12  to size and select a patella prosthetic component suitable for use with the particular patient&#39;s patella. After the patella prosthetic component is selected, the surgeon may use the guide  12  and the gasket  14  to secure the selected patella prosthetic component to the patient&#39;s resected patella. 
     As shown in  FIG. 1 , the guide  12  of the instrument  10  includes a housing  20  and a clamping bracket  22  configured to move relative to the housing  20 . The housing  20  has a main body  24  and a handle  26  extending downwardly from the main body  24 . The handle  26  includes a plurality of ribs  28  that define a grip  30 , which is sized to be grasped by a hand of a surgeon. The housing  20  also includes a support bracket  32  that extends from the main body  24  opposite the handle  26 . The support bracket  32  has a mounting plate  34  configured to engage the anterior side of the patient&#39;s resected patella  16 . 
     The clamping bracket  22  of the guide  12  includes a beam  36  and a drill plate  38  attached to the beam  36 . The beam  36  is received in a passageway  40  defined in the main body  24  of the housing  20  and is configured to slide relative to the housing  20 . The guide  12  also has a clamp actuation mechanism  42  that includes a lever or trigger arm  44  extending downwardly from the main body  24  of the housing  20 . The trigger arm  44  is configured to pivot relative to the housing  20  when force is applied as indicated by arrow  46 . By operating the trigger arm  44 , the drill plate  38  of the clamping bracket  22  may be advanced toward the mounting plate  34  of the support bracket  32 , as described in greater detail below. 
     The beam  36  of the clamping bracket  22  extends outwardly from the passageway  40  of the housing  20  to an end  50 . A pair of mounting arms  52 ,  54  extends upwardly from the end  50  of the beam  36 , and the drill plate  38  is secured to the mounting arms  52 ,  54 . In the illustrative embodiment, the drill plate  38  and the beam  36  are formed separately and later assembled. It should be appreciated that in other embodiments the beam  36  and the drill plate  38  may be molded or otherwise formed as a single monolithic component. 
     The drill plate  38  of the clamping bracket  22  has a planar clamping surface  56  that faces the mounting plate  34 , a front surface  58  opposite the clamping surface  56 , and a side wall  60  that connects the surfaces  56 ,  58 . A plurality of teeth  62  extend from the clamping surface  56  toward the mounting plate  34  of the support bracket  32 , and each tooth  62  includes a tip  64  configured to engage the patient&#39;s resected patella  16 . As shown in  FIG. 1 , the drill plate  38  includes three teeth  62  that are arranged in a triangular pattern on the clamping surface  56 . It should be appreciated that in other embodiments the drill plate  38  may include additional teeth or fewer teeth arranged in other geometric patterns. Additionally, in other embodiments, the teeth may be removably attached to the drill plate  38 . 
     The drill plate  38  also includes a plurality of cylindrical openings  66  extending through the surfaces  56 ,  58 . The openings  66  are arranged in a triangular pattern, and each opening  66  has a bushing  68  positioned therein. A guide hole  70  of the drill plate  38  is defined through each bushing  68 , and each guide hole  70  has a longitudinal axis  72  extending therethrough. As described in greater detail below, each guide hole  70  is sized to receive a surgical drill  74  (see  FIG. 11 ) and guide the drill  74  along the axis  72  into contact with the patient&#39;s resected patella  16 . In the illustrative embodiment, the drill plate  38  has three guide holes  70 . It should be appreciated that in other embodiments the drill plate  38  may include additional or fewer guide holes  70  arranged in a geometric patterns other than the triangular pattern shown in  FIG. 1 . 
     The bushings  68  of the drill plate  38  are formed from a metallic material such as stainless steel. In other embodiments, the bushings  68  may be formed from a polymeric material resistant to wear. It should also be appreciated that in other embodiments the bushings  68  may be omitted. 
     The housing  20  and the beam  36  of the clamping bracket  22  are each formed from a polymeric material, such as, for example, polyethylene. In other embodiments, the housing  20  and the beam  36  may be formed from a metallic material such as stainless steel. The drill plate  38  is formed from a substantially transparent material. In the illustrative embodiment, the drill plate  38  is formed from an acrylate polymer, such as, for example, polycarbonate. It should also be appreciated that the drill plate  38  may be formed from other substantially transparent material, such as, for example, methyl acrylate or glass. 
     Referring now to  FIGS. 2 and 3 , the drill plate  38  of the clamping bracket  22  includes multiple indicators  80  that correspond to multiple sizes of the patient&#39;s patella. The indicators  80  include a plurality of etch marks  82  that are defined in the clamping surface  56 , each of which corresponds to a different size of a patient&#39;s patella. As shown in  FIG. 2 , the etch marks  82  are arranged as a number of inscribed lines  84  that indicate narrow and intermediate sizes. The indicators  80  also include an outer circumference  86  of the side wall  60  of the drill plate  38 , which indicates the widest patella size of the patella sizes indicated by the indicators  80 . In other embodiments, the drill plate  38  may be larger and include additional indicators  80  corresponding to other possible sizes of the patient&#39;s patella. 
     Each of the indicators  80  is identified by a corresponding numerical symbol  88 , which, in turn, corresponds to a particular patella size. When the indicators  80  are viewed as shown in  FIG. 2 , the numerical symbols  88  appear backward or mirrored. When viewed as shown in  FIG. 3 , the etch marks  82  and the numerical symbols  88  are properly oriented and visible through the front surface  58  because the drill plate  38  is substantially transparent. Similarly, when a patient&#39;s resected patella is positioned between the drill plate  38  and the mounting plate  34 , the patella is also visible through the front surface  58 . It should be appreciated that in other embodiments the lines and indicators may be formed on the plate  38  via printing or painting rather than by etching. 
     Referring now to  FIGS. 4-7 , the clamp actuation mechanism  42  of the guide  12  is shown in greater detail. As described above, the clamp actuation mechanism  42  includes a trigger arm  44  that extends downwardly from the main body  24  of the housing  20 , and the trigger arm  44  may be operated to move the clamping bracket  22  relative to the housing  20  in the direction indicated by arrow  98 . The trigger arm  44  has a body  100  including a lower lever arm  102  positioned below the main body  24  adjacent to the handle  26 . The body  100  also includes an upper lever arm  104  that is positioned within the main body  24  of the housing  20 . 
     As shown in  FIG. 4 , the body  100  of the trigger arm  44  is attached to the main body  24  via a joint  106 . The joint  106  includes a cylindrical pin  108  positioned in a cylindrical opening  110  defined through the body  100  and a pair of mounting holes (not shown) defined in the main body  24  of the housing  20 . In that way, the trigger arm  44  is configured to pivot relative to the housing  20  between the extended position shown in  FIG. 4  and the compressed position shown in  FIG. 5 . 
     The clamp actuation mechanism  42  also includes an actuation plate  112  that has a front surface  114  and a rear surface  116 . As shown in  FIGS. 4-7 , the upper lever arm  104  of the trigger arm  44  includes a cam surface  118  that engages the front surface  114  of the actuation plate  112 . The clamp actuation mechanism  42  also includes a biasing element, such as, for example, a spring  120 , which extends over the beam  36  of the clamping bracket  22  and is positioned between rear surface  116  of the actuation plate  112  and an inner wall  122  of the housing  20 . The spring  120  is configured to bias the clamp actuation mechanism  42  in the extended position shown in  FIG. 4 . 
     The actuation plate  112  of the clamp actuation mechanism  42  has a closed slot  124  extending through the surfaces  114 ,  116  of the plate  112 . As shown in  FIG. 4 , the actuation plate  112  is positioned over the beam  36 , and the beam  36  extends through the slot  124 . The slot  124  is defined by an inner wall  126  that extends between the surfaces  114 ,  116 . The inner wall  126  of the actuation plate  112  includes a pair of engagement edges  128 ,  130  that grip an upper surface  132  and a lower surface  134 , respectively, of the beam  36 . 
     The guide  12  of the instrument  10  also includes a locking mechanism  136  that inhibits movement of the clamping bracket  22  relative to the housing  20 , including selectively preventing movement of the bracket  22  in the direction indicated by arrow  138 . The locking mechanism  136  includes a locking plate  140  positioned in the main body  24  of the housing  20  and a release button  142  attached to a lower end  144  of the locking plate  140 . The release button  142  includes a contoured front surface  146  and a rear surface  148  opposite the front surface  146 . The locking mechanism  136  also includes a biasing element, such as, for example, a spring  150  that is positioned between the rear surface  148  of the button  142  and an inner wall  152  of the housing  20 . 
     An upper end  154  of the locking plate  140  is positioned in a slot  156  defined between a pair of flanges  158  of the housing  20 . The locking plate  140 , like the actuation plate  112 , has a closed slot  160  extending therethrough. As shown in  FIG. 4 , the locking plate  140  is positioned over the beam  36 , and the beam  36  extends through the slot  160 . The slot  160  is defined by an inner wall  162  having a pair of engagement edges  164 ,  166  that grip the upper surface  132  and the lower surface  134 , respectively, of the beam  36  to inhibit movement of the clamping bracket  22  relative to the housing  20 . 
     In use, the surgeon may utilize the clamp actuation mechanism  42  to advance the drill plate  38  of the clamping bracket  22  toward the mounting plate  34  of the support bracket  32 . To do so, the surgeon or other user exerts a force on the lower lever arm  102  of the trigger arm  44  in the direction indicated by arrow  46 . The force is transferred from the trigger arm  44  to the actuation plate  112  through the engagement of the cam surface  118  of the upper lever arm  104  with the front surface  114  of the actuation plate  112 . As force is applied to the lower lever arm  102 , the engagement edges  128 ,  130  of the actuation plate  112  grip the upper surface  132  and the lower surface  134 , respectively, of the beam  36 , and the actuation plate  112  pushes against the spring  120 . When a predetermined amount of force is applied to the trigger arm  44 , the actuation plate  112  overcomes the bias of the spring  120  and the drill plate  38  advances toward the mounting plate  34  in the direction indicated by arrow  98 . 
     As shown in  FIGS. 4 and 5 , the upper lever arm  104  of the trigger arm  44  moves downward along the front surface  114  of the actuation plate  112  as the trigger arm  44  pivots relative to the housing  20 . The beam  36  of the clamping bracket  22  is drawn by the actuation plate  112  through the passageway  40 , moving along an axis  170  that extends parallel to the longitudinal axes  72  defined by the guide holes  70  of the drill plate  38 . The movement of the clamping bracket  22  relative to the housing  20  continues until the lower lever arm  102  of the trigger arm  44  contacts the handle  26  in the compressed position shown in  FIG. 5 . 
     When the user releases the trigger arm  44 , the removal of the force exerted by the upper lever arm  104  causes the engagement edges  128 ,  130  of the actuation plate  112  to disengage from the surface  132 ,  134 , respectively, of the beam  36 . The spring  120  urges the actuation plate  112  to move in the direction indicated by arrow  172  while the clamping bracket  22  is held in position relative to the housing  20  by the locking mechanism  136 . The force exerted by the spring  120  is transferred from the actuation plate  112  to the trigger arm  44  through the engagement of the front surface  114  of the actuation plate  112  with the cam surface  118  of the upper lever arm  104 . The trigger arm  44  is thereby urged to pivot relative to the housing  20  in the direction indicated by arrow  174  and return to the extended position shown in  FIG. 6 . 
     In the extended position, the trigger arm  44  is prevented from pivoting further relative to the housing  20 , and the actuation plate  112  is locked in position between the spring  120  and the upper lever arm  104 . In that position, the engagement edges  128 ,  130  of the actuation plate  112  grip the upper surface  132  and the lower surface  134 , respectively, of the beam  36 . The surgeon or user may repeat the steps outlined above to advance the drill plate  38  closer to the mounting plate  34 . 
     When the surgeon or other user desires to move the drill plate  38  away from the mounting plate  34 , the surgeon may actuate the release button  142  to release the locking mechanism  136 , thereby permitting the clamping bracket  22  to move in the direction indicated by arrow  138 , as shown in  FIGS. 6 and 7 . To do so, a predetermined amount of force is applied to the contoured front surface  146  of the button  142  in the direction indicated by arrow  168  to overcome the bias exerted by spring  150 . When a sufficient amount of force is applied, the locking plate  140  tilts such that the engagement edges  164 ,  166  of the locking plate  140  are released from the surfaces  132 ,  134  of the beam  36 , as shown in  FIG. 7 . The clamping bracket  22  may then be manually moved along the axis  170  in the direction indicated by arrow  138  to any position relative to the housing  20 . The user is prevented from detaching the clamping bracket  22  from the housing  20  by a stop  176  defined on an end  178  of the beam  36 . When the clamping bracket  22  is located at the desired position, the button  142  may be released to re-engage the edges  164 ,  166  of the locking plate  140  with the surfaces  132 ,  134  of the beam  36  and thereby prevent further movement of the clamping bracket  22  relative to the housing  20 . 
     Referring now to  FIG. 8 , the compression gasket  14  is shown in greater detail. The gasket  14  has a body  180  formed from an elastomeric material such as rubber. It should be appreciated that in other embodiments the body  180  may be formed from a polymeric material. The body  180  has a side surface  182  that is concave and is configured to receive a portion of the patella prosthetic component  18 , as will be described in greater detail below. 
     The body  180  of the gasket  14  has another side surface  184  opposite the side surface  182 . A plurality of mounting plugs  92  extend from the side surface  184 . Each mounting plug  92  is sized to be received in a corresponding guide hole  70  of the drill plate  38 . The body  180  also has a plurality of holes  190  defined in the side surface  184  that are sized to receive each of the teeth  62  extending from the clamping surface  56  of the drill plate  38 . 
     A tab  186  extends outwardly from the body  180  of the gasket  14 . The tab  186  includes a pair of contoured surfaces  188  configured to receive the fingertips of the user. In use, the user may grip the surfaces  188  to move the gasket  14  relative to the drill plate  38 , thereby moving the gasket  14  out of the drilling path when preparing to drill holes in a patient&#39;s resected patella. In that way, the plugs  92  of the gasket  14  may be moved into and out of the guide holes  70  of the drill plate  38 . 
     The mounting plugs  92  include a central plug  192  having a configuration that substantially corresponds to the configuration of the central aperture  94  of the drill plate  38 . In particular, the central plug  192  includes a trio of arms  194  that are sized and arranged to fit in the corresponding trio of extension slots  96  of the aperture  94  such that the gasket  14  is attached to the drill plate  38  in a predetermined orientation. 
     As described above, the guide  12  may be utilized to surgically prepare a patient&#39;s resected patella  16  for implantation of a patella prosthetic component  18 , as shown in  FIGS. 9-12 . To do so, the surgeon may position the resected patella  16  between the mounting plate  34  and the drill plate  38  of the guide  12  with the compression gasket  14  decoupled from the guide  12 . As shown in  FIG. 9 , the patient&#39;s resected patella  16  may be positioned between the plates  34 ,  38  such that an anterior surface  200  of the resected patella  16  faces a planar clamping surface  202  of the mounting plate  34  and a resected posterior surface  204  of the resected patella  16  faces the planar clamping surface  56  of the drill plate  38 . 
     The planar clamping surface  202  of the mounting plate  34  extends parallel to the planar clamping surface  56  of the drill plate  38  and includes a plurality of teeth  206  extending therefrom. When the patient&#39;s resected patella  16  is positioned between the plates  34 ,  38 , the surgeon may move the anterior surface  200  of the patient&#39;s resected patella  16  into contact with the plurality of teeth  206  of the planar clamping surface  202 . The surgeon may also clamp the patient&#39;s resected patella  16  between the plates  34 ,  38  by operating the clamp actuation mechanism  42  as described above to advance the drill plate  38  toward the mounting plate  34 . 
     Additionally, the surgeon may use the guide  12  to select a patella prosthetic component. As shown in  FIG. 10 , the outer margin  208  of the patient&#39;s resected patella  16  falls within one of the indicators  80 , which corresponds to a particular size. Using the indicators  80 , the surgeon may select a patella prosthetic component that offers the maximum coverage of the resected posterior surface  204  of the resected patella  16 . 
     After the surgeon has clamped the patient&#39;s resected patella  16  between the plates  34 ,  38  of the guide  12 , the resected posterior surface  204  of the patella  16  is surgically-prepared to receive the patella prosthetic component  18 . As shown in  FIG. 11 , the surgeon may drill a series of pilot holes in the surface  204  that correspond to the position of a number of mounting pegs  210  of the component  18 . To do so, the surgeon may insert a surgical drill  74  into each of the guide holes  70  defined in the drill plate  38 . The drill  74  is advanced along the axis  72  through the guide hole  70  and into contact the surface  204 . The surgeon activates the drill  74  and advances the drill  74  along the guide hole  70  until a pilot hole of sufficient depth is formed in the patient&#39;s resected patella  16 . The surgeon may then repeat the drilling operation through each of the guide holes  70  until the required pilot holes are created. At any time, the surgeon may actuate the release button  142  and manually unclamp the patient&#39;s resected patella  16 . 
     After pilot holes are created in the resected posterior surface  204 , the surgeon may position the patella prosthetic component  18  for attachment to the patient&#39;s resected patella  16  and apply cement to the anterior surface  212  of the component  18 . After the component  18  is positioned over the patient&#39;s resected patella  16 , the pegs  210  may be advanced into the pilot holes formed in the resected posterior surface  204  until the anterior surface  212  is placed into contact with the surface  204 . The compression gasket  14  may be attached to the drill plate  38 , thereby covering the teeth  62  extending outwardly from the clamping surface  56 . In that position, the gasket  14  is positioned between the drill plate  38  and the component  18 . 
     The surgeon may again operate the clamp actuation mechanism  42  to clamp the component  18  to the patient&#39;s resected patella  16 , as shown in  FIG. 12 . To do so, the surgeon may squeeze the lower lever arm  102  to apply a predetermined amount of force to the trigger arm  44  to move the drill plate  38  and gasket  14  toward the mounting plate  34 . The compression gasket  14  is advanced into contact with the posterior bearing surface  214  of the component  18 , and the component  18  is seated within and stabilized by the concave surface  182  of the gasket  14  such that the component  18  is clamped firmly to the patient&#39;s resected patella  16  until polymerization is complete and the component  18  is secured to the patient&#39;s resected patella  16 . 
     While the disclosure has been illustrated and described in detail in the drawings and foregoing description, such an illustration and description is to be considered as exemplary and not restrictive in character, it being understood that only illustrative embodiments have been shown and described and that all changes and modifications that come within the spirit of the disclosure are desired to be protected. For example, the gasket  14  may be omitted from embodiments of the instrument  10  where, for example, the teeth of the drill guide are removable or omitted. 
     There are a plurality of advantages of the present disclosure arising from the various features of the method, apparatus, and system described herein. It will be noted that alternative embodiments of the method, apparatus, and system of the present disclosure may not include all of the features described yet still benefit from at least some of the advantages of such features. Those of ordinary skill in the art may readily devise their own implementations of the method, apparatus, and system that incorporate one or more of the features of the present invention and fall within the spirit and scope of the present disclosure as defined by the appended claims.