Patent Publication Number: US-2023139058-A1

Title: Dual-purpose orthopedic surgery instrument

Description:
BACKGROUND OF THE INVENTION 
     The present invention generally relates to a dual-purpose orthopedic surgery instrument. More specifically, the dual-purpose orthopedic surgery instrument doubles as a modular impactor alone and as a weight component of a slap hammer when combined with an extractor. 
     Knee arthroplasty requires numerous instruments to prepare the tibia and femur for knee replacement components, and insertion and/or extraction of those components. For example, once the proximal end of the tibia is resected, a surgeon may use a tibial trial component to determine what size tibial component should be implanted as part of the orthopedic surgical procedure. The trial component also ensures that proper cuts were made during resection and notifies the surgeon if further alterations are required. Trial components are inserted via an impactor instrument that includes a handle with an impactor head on one end and a strike plate on the other. Generally, a surgeon will locate the impactor head on the trial component and impart a force to the strike plate with a hammer or the like to drive the trial component into the bone. A similar process may be used with femoral trial components on the distal end of the femur. 
     Another instrument that may be used during a knee arthroplasty procedure is an extractor, which removes the trial components and other surgical instruments (e.g., cut blocks, broaches, etc.) from the bone to allow for implantation of the actual knee replacement components. A slap hammer is one type of extractor known in the art having a weight slidably coupled to a rod that connects to the implanted trial component. The surgeon may slide the weight along the rod until the weight contacts a stopper, thereby creating an impulse that dislodges the implanted trial component. Moreover, a slap hammer may be used during knee revision to facilitate removal of previously implanted knee replacement components. Knee revision surgery may be required when implanted components need to be removed due to injury, wear, infection, or if there were issues with the original knee arthroplasty. In any case, after the trial components or other previously implanted components are removed, the surgeon may insert the new knee replacement components via the impactor as stated above. 
     Typically, the suite of instruments delivered to the operating room to perform knee arthroplasty will have various impactors for positioning and implanting trial and final components and a slap hammer or multiple slap hammers to extract components that have been impacted into bone. The impactors and slap hammer(s) are generally located on surgical trays that include additional surgical equipment and/or component parts. Because different components require different impactors and/or slap hammers, the surgical trays may take up more space than desirable in an operating room. Furthermore, there are mass constraints on the surgical trays and therefore the use of multiple impactors and slap hammers can require additional surgical trays. This exacerbates the issue of instruments and trays crowding an otherwise space constrained operating room. Furthermore, there are substantial costs associated with sterilizing all of the impactors, slap hammers, surgical equipment, and knee replacement components. As such, convention still requires the use of multiple individual surgical instruments that increase the mass of surgical trays, number of surgical trays, and/or sterilization costs of knee arthroplasties. 
     There exists, therefore, a significant need in the art for a dual-purpose orthopedic surgery instrument usable as a modular impactor when used alone with an impactor head that selectively couples thereto and usable as a weight component of a slap hammer when selectively coupled along the length of an extractor in slidable relation relative thereto. The present invention fulfills these needs and provides further related advantages. 
     SUMMARY OF THE INVENTION 
     In general, the dual-purpose orthopedic surgery instrument disclosed herein serves as a modular impactor when used alone with an impactor head selectively coupled to an impactor interface of an impactor block opposite a strike block, and serves as a weight component of a slap hammer when an extractor rod selectively couples thereto in slidable relation therewith. 
     More specifically, in one embodiment, the dual-purpose orthopedic instrument as disclosed herein may include an elongated body, an impactor block formed from a first end of the elongated body selectively couplable with a modular impactor head, a strike block formed from a second end of the elongated body including a strike surface for selectively receiving a strike force thereon, and an externally accessible channel having a size and shape for pass-through reception and select retention of an extractor rod therein. As such, the elongated body is usable as a modular impactor when the impactor block is selectively coupled with the impactor head and as a weight of a slap hammer when selectively coupled with the extractor rod in slidable relation relative thereto. 
     In some embodiments, the first end may include a tapered channel having a size and shape for at least partial reception of a first end of the extractor rod at an angle offset from a longitudinal axis of the elongated body while at the same time a second end of the extractor rod may simultaneously extend out from the externally accessible channel. Moreover, the second end may include a receiving channel having a size and shape for tilt-in insertion of the second end of the extractor rod through the externally accessible channel. In this respect, at least a portion of the extractor rod may be keyed for insertion within the receiving channel in a predetermined orientation. To key the orientation of the extractor rod within the receiving channel, at least a portion of the extractor rod may include a pair of planar surfaces located along a length thereof positioned to abut a commensurate pair of interior planar surfaces of the receiving channel when the extractor rod is inserted therein. Here, the abutting planar surfaces prevent coaxial rotation of the extractor rod relative to the elongated body. 
     Upon full insertion of the extractor rod within the receiving channel, the extractor rod may reside substantially coaxial within the externally accessible channel and in slidable relation with within the elongated body. The extractor rod may further include a stopper relatively smaller than the externally accessible channel yet relatively larger than the tapered channel and the receiving channel for purposes of removably retaining the extractor rod within the elongated body between the first end and the second end after being tilted into engagement with the elongated body. Here, the extractor rod may be of a length at least partially residing within the first end when the stopper is seated within the tapered channel and at least partially residing within the second end when the stopper is in contact with the first end. The externally accessible channel may be in the form of an arcuate channel such that the stopper is relatively larger than an upper section and a lower section of the arcuate channel and relatively smaller than a middle section of the arcuate channel for pass-through reception therewith. 
     In another aspect of the embodiments disclosed herein, the impactor block may include a spring-actuated button at least partially residing within an internal enclosure of the strike block and generally biasing a lock in a normal closed position at least partially enclosing the receiving channel. Doing so may help prevent slide-out removal of the second end of the extractor rod from the elongated body. In one embodiment, the lock may include a chamfered latch self-actuable by the second end of the extractor rod, i.e., the extractor rod may simply slidably engage and displace the chamfered latch to open access to the receiving channel for receipt of the extractor rod therein. 
     In an alternative embodiment, the externally accessible channel may include a locking slot formed from a portion of one of the impactor block or the strike block. Here, a lever normally positioned within the externally accessible channel may generally block passthrough movement of the outwardly projecting stopper formed along a length of the extractor rod. An externally accessible button may be actuable to selectively displace the lever out from within the externally accessible channel, thereby permitting the outwardly projecting stopper to pass therethrough. When in this open position, the extractor rod may be selectively inserted and/or withdrawn from the elongated body. 
     In other embodiments as disclosed herein, the modular impactor head may include an aperture having a size and shape for pass-through reception of at least a portion of the extractor rod. Additionally, the strike surface may be an angled surface offset from a longitudinal axis of the elongated body, or the strike surface may be a non-planar strike surface selected from the group consisting of a curved surface, a spherical surface, and a spheroidal surface. Additionally, the elongated body may include a tab outwardly extending therefrom selectively couplable to an orthopedic component and the impactor block may include an impactor interface having a size and shape for select coupling to the impactor head via snap-fit engagement, threaded engagement, or slide-fit engagement. 
     In another embodiment, a slap hammer as disclosed herein may include a handle having an externally accessible channel wherein a first end of the handle includes a tapered channel formed therein and a second end of the handle includes a receiving channel formed therein. The slap hammer may further include an extractor rod having an outwardly extending stopper formed along a length thereof, wherein the stopper is of a size and shape relatively smaller than the externally accessible channel while being relatively larger than the tapered channel and the receiving channel. The extractor rod may be at least partially insertable into the tapered channel at an angle offset from a longitudinal axis of the handle and tiltable therein to pass the stopper through the relatively larger externally accessible channel for insertion of the extractor rod into the receiving channel in coaxial relation relative to the handle. Thereafter, the handle is movable along the length of the extractor rod as a weight of the slap hammer and remains constrained to the extractor rod by the stopper between the first end and the second end. 
     In these embodiments, the first end may include an impactor block selectively couplable with a modular impactor head and the second end may include a strike block having a strike surface for selectively receiving a strike force thereon. Moreover, the externally accessible channel may be an arcuate channel, wherein the stopper is relatively larger than an upper section and a lower section of the arcuate channel and relatively smaller than a middle section thereof. At least a portion of the extractor rod may be keyed for insertion within the receiving channel in a predetermined orientation. More specifically with respect to this feature, at least a portion of the extractor rod may include a pair of planar surfaces located along a length thereof positioned to abut a commensurate pair of interior planar surfaces of the receiving channel, the abutting planar surfaces thereby prevent coaxial rotational movement of the extractor rod relative to the elongated body. Additionally, the extractor rod may at least partially reside within the first end when the stopper is seated within the tapered channel and may at least partially reside within the second end when the stopper is in contact with the first end. 
     In another aspect of these embodiments, a button may generally bias a lock in a normal closed position at least partially enclosing the receiving channel thereby preventing slide-out removal of the extractor rod therefrom. Here, the lock may include a chamfered latch self-actuable by the extractor rod to facilitate push-in reception thereof without the need to actuate the button. The button may more specifically be spring-actuated and at least partially reside within an internal enclosure of the first end of the handle. 
     In another embodiment as disclosed herein, a process for extracting an orthopedic component with a dual-purpose orthopedic instrument may include steps for inserting an extractor rod into an externally accessible channel of a weight at an angle offset from a longitudinal axis thereof, tilting the extractor rod into the externally accessible channel until the extractor rod is generally coaxially aligned within the weight, attaching the extractor rod to an orthopedic component, sliding the weight along at least a portion of the extractor rod, and creating an impulse sufficient to extract the orthopedic component. 
     More specifically, the creating step may include impacting the weight against an outwardly extending collar formed along a length of the extractor rod to generate the extracting impulse. Here, the collar may be of a size and shape to permit passing the collar through the externally accessible channel as part of the tilting step. Once the extractor rod is engaged with the handle, the extractor rod may be constrained therein by way of the collar being positioned between an impactor block formed from a first end of the weight and a strike block formed from a second end of the weight. As such, the sliding step may further include passing at least a portion of the extractor rod through a tapered channel formed through the impactor block and a receiving channel formed through the strike block, both the tapered channel and the receiving channel being of a size and shape relatively smaller than the collar to stop sliding movement of the extractor rod therein when coming into contact with the collar. 
     Moreover, the tilting step may further include orienting the extractor rod in a predetermined orientation keyed for reception within a receiving channel, including passing the extractor rod over a chamfered latch of a self-actuable lock for locking engagement therein once the extractor rod clears the chamfered latch. To remove, an externally accessible button may be pressed to operably open the self-actuable lock, thereby allowing the extractor rod to be tilted out from engagement with the weight. 
     In accordance with another embodiment disclosed herein, the dual-purpose orthopedic surgery instrument may include an elongated handle terminating in an impactor block having an impactor interface that may selectively couple to at least one modular impactor head at one end and a strike block at another end thereof. The elongated handle may further include one or more elongated channels starting at the strike block and generally extending along the length of the elongated handle and terminating at the impactor block. 
     In another embodiment, the elongated handle may be ergonomically shaped and the modular impactor interface may include a recess for selectively coupling to at least one modular impactor head via snap-fit or slide-fit engagement. Alternatively, the impactor interface may selectively couple an impactor head via threaded engagement. In another embodiment, the strike block may include a flat or curved strike surface, wherein the curved strike surface may include a spherical surface or a spheroidal surface. In another embodiment, the strike surface may be angled relative to the longitudinal axis of the dual-purpose orthopedic surgery instrument. The strike block may further include a keyed rod-receiving channel for retaining an extractor rod to form a slap hammer when coupled thereto. A spring-loaded button housed within an enclosure of the strike block may help retain the extractor head within the dual-purpose orthopedic surgery instrument. In one embodiment, the spring-loaded button may have an externally accessible corrugated tab and be biased into a normal engaged position by a latch. The spring-loaded button may be selectively pressed into an open position aligning the spring-loaded button opening with the keyed rod-receiving channel, and released into a closed position wherein the spring-loaded button latch extends into the elongated handle channel to hook the extractor rod therein. 
     In another embodiment, an extractor rod may be inserted into and extend through the elongated channel, wherein the extractor rod may be removably constrained therein. Here, the elongated handle may couple to the extractor rod in slidable relation relative thereto, thereby allowing the dual-purpose orthopedic surgery instrument to be used as a slap hammer. Of course, the dual-purpose orthopedic surgery instrument can still be used as a modular impactor when the rod is removed from the handle. The extractor rod may include a tibial extractor coupled to one end and a femoral extractor coupled to the other. Alternatively, the ends of the extractor rod may be adapted to couple to tibial trials, femoral trials, insert trials, implant components, or intramedullary rods. The extractor rod may also include a stopper with a width small enough to fit within the elongated channel but large enough to prevent the extractor rod from completely sliding off of the strike block and the impactor block. In another embodiment, extractor rod may be prevented from disassembly with the elongated handle via the spring-loaded button and latch while the device is used as an extractor or slap hammer. The extractor rod may have a keyed-cross section, such as two opposing flat sides and two opposing rounded sides. Alternatively, the extractor rod, the elongated channel, and the stopper may have a cross-section that is circular, square, or triangular to facilitate keyed engagement. The extractor rod may couple to tibial trials, femoral trials, insert trials, implant components, or intramedullary rods via snap-fit coupling, slide-fit coupling, or threaded coupling. In yet another embodiment, the stopper and the extractor rod may be of a unibody construction, or may be two separately formed pieces that couple together. The impactor block may also include a tab for positioning a tibial insert. 
     Other features and advantages of the present invention will become apparent from the following more detailed description, when taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings illustrate the invention. In such drawings: 
         FIG.  1    is a perspective view of a dual-purpose orthopedic surgery instrument as disclosed herein; 
         FIG.  2    is a perspective view of the dual-purpose orthopedic surgery instrument of  FIG.  1   , further illustrating a modular impactor head coupled to an impactor interface opposite a strike block; 
         FIG.  3    is a perspective view of the dual-purpose orthopedic surgery instrument, further illustrating a spring-activated button in exploded relation relative to a recess in the strike block; 
         FIG.  4    is a top plan view of the spring-activated button, further illustrating a cavity formed therein for selectively receiving and retaining an extractor rod therein; 
         FIG.  5    is a perspective view of an extractor rod having a keyed cross-section selectively engageable with the keyed rod-receiving channel of the dual-purpose orthopedic surgery instrument; 
         FIG.  6    is a perspective view illustrating engagement of the dual-purpose orthopedic surgery instrument along a length of the extractor rod; 
         FIG.  7    is a bottom plan view of the dual-purpose orthopedic surgery instrument, further illustrating a bottom channel and recess formed longitudinally through the handle having a tapered inner wall at the modular impactor interface; 
         FIG.  8    is an enlarged perspective view taken about the circle  8  in  FIG.  6   , further illustrating a stopper outwardly extending from the extractor rod and located within a slide channel of the dual-purpose orthopedic surgery instrument; 
         FIG.  9    is a cross-sectional view of the extractor rod taken about the line  9 - 9  in  FIG.  6   ; 
         FIG.  10    is a perspective view illustrating a femoral trial interface engaged with a femoral trial component; 
         FIG.  11    is a perspective view of a tab coupled to a tibial insert for positioning the tibial insert on a tibial component; 
         FIG.  12    is cross-sectional view taken about the line  12 - 12  in  FIG.  6   , further illustrating relative sizing of the stopper to each of a first shoulder in the impactor block and a second shoulder in the strike block; 
         FIG.  13    is an enlarged cross-sectional view taken about the line  14 - 14  in  FIG.  8   , further illustrating an internal enclosure housing a spring-loaded latch in the strike block; 
         FIG.  14    is an enlarged perspective view similar to  FIG.  8    omitting the strike plate to further illustrate the positioning of the latch relative to the extractor rod when the spring-loaded button is in a depressed position; 
         FIG.  15    is an alternative enlarged bottom perspective view similar to  FIGS.  8  and  14    omitting the spring-loaded button to illustrate a pair of pin retaining apertures formed in the strike block; 
         FIG.  16    is a perspective view of an alternative embodiment of the dual-purpose orthopedic surgery instrument having a locking slot selectively permitting coaxial pass-through insertion and retention of the extractor rod therethrough; 
         FIG.  17 A  is a top plan view of the locking slot in a closed position by way of a lever at least partially extending therein; 
         FIG.  17 B  is a top plan view of the locking slot in an open position by way of the lever being generally pivoted out from within the locking slot by an externally accessible spring-actuated lever button; and 
         FIG.  18    is an enlarged perspective view taken about the circle  18  in  FIG.  16   , further illustrating the stopper of the extractor rod constrained within the slide channel when the locking slot is returned to the closed position after the stopper passes through the previously enlarged locking slot. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     As shown in the exemplary drawings for purposes of illustration, the present invention for a dual-purpose orthopedic surgery instrument is generally illustrated in  FIGS.  1 - 3 ,  6 - 8 ,  10 - 12 , and  14 - 16  and  18    with respect to reference numeral  20 . In general, the dual-purpose orthopedic surgery instrument  20  may include an elongated handle  22  terminating in an impactor block  24  having an impactor interface  25  at one end and a strike block  26  at another end thereof. The elongated handle  22  may be ergonomically formed (e.g., in an oval or bulbous configuration suitable for gripping) that includes at least one elongated channel  28  formed therein to at least facilitate slide-in engagement of an extractor rod  30  ( FIGS.  5 - 6 ,  8 ,  10 ,  12 - 14 ,  16 , and  18   ), wherein the combination forms a slap hammer  32  as discussed in more detail below. In this respect, the dual-purpose orthopedic surgery instrument  20  can operate as an impactor instrument when used alone with a modular impactor head  34  coupled to the impactor interface  25  ( FIG.  2   ), and also as a slide weight as part of the slap hammer  32 , e.g., as illustrated in  FIGS.  6 ,  12 ,  16 , and  18   . Accordingly, such versatility of the dual-purpose orthopedic surgery instrument  20 , including by way of the fact that the impactor interface  25  may couple to different modular impactor heads  34  of various sizes and configurations, the number of surgical instruments required in the operating room can be significantly reduced. 
     More specifically, in one use, a surgeon may use the dual-purpose orthopedic surgery instrument  20  as a modular impactor by selectively coupling the modular impactor head  34  to the impactor interface  25  of the impactor block  24 . In one embodiment, the impactor block  24  may include a recess  36  that facilitates snap-fit engagement with the modular impactor head  34 . Here, the modular impactor head  34  may have a protrusion (not shown) that mates with the recess  36  by extending into the recess  36 . For example, the protrusion may have a groove containing an O-ring configured to mate with a lip in the recess  36 . The lip may extend into the groove containing the O-ring thereby facilitating snap-fit coupling between the modular impactor head  34  and impactor interface  25 . In alternative embodiments, the modular impactor head  34  may couple to the recess  36  and/or the impactor interface  25  via a threaded coupling. Here, the recess  36  may include a set of internal threads and the modular impactor head  34  may include a set of external threads of a size and shape to engage the internal threads of the recess  36  such that the modular impactor head  34  can screw on to the dual-purpose orthopedic surgery instrument  20  in thread-tight relationship. In another embodiment, the impactor interface  25  may include a channel extending to the peripheral edge thereof and the modular impactor head  34  may couple thereto by sliding into said channel in the impactor interface  25 . Although, of course, the modular impactor head  34  may couple to the impactor interface  25  by other methods known in the art for securing components adjacent to one another. 
     The modular impactor head  34  illustrated in  FIG.  2    includes a set of projections  38  (three) that may correspond to three indents or recesses formed in a knee replacement trial or component (not shown). Alternatively, the modular impactor head  34  may include fewer than three of the projections  38  (e.g., one or two of the projections  38 ) or more than the three projections  38 . Conversely, the modular impactor head  34  may include a plurality of indentations that correspond to a plurality of protrusions projecting out from the knee replacement trial or component. In another alternative embodiment, the modular impactor  34  may be substantially flat (i.e., including none of the projections  38 ). Of course, any impactor head known in that art able to couple to or otherwise adapt for use with the impactor interface  25  may be used. Once the modular impactor head  34  is coupled to the impactor interface  25 , the surgeon may position the modular impactor head  34  on a trial or implant component surface for use of the dual-purpose orthopedic surgery instrument  20  as an impactor. 
     In general, as best illustrated in  FIG.  3   , the surgeon may apply a strike force along an arrow  40  to a strike surface  42  of the strike block  26 , e.g., by way of a hammer or the like during surgery, to impact a trial or implant component into a patient bone (e.g., the proximal end of a tibia and/or distal end of a femur). The strike surface  42  may be a substantially flat surface best shown in  FIGS.  8 ,  13  and  16 - 18   , or the strike surface  42  may include a non-planar surface such as a curved, spherical, or spheroidal surface. The strike block  26  and the strike surface  42  may also be generally parallel to the impactor block  24 , or the strike surface  42  may formed as an angled strike surface angularly offset from a longitudinal axis of the impactor block  24  where the modular impactor head  34  is couples to the impactor interface  25 . 
     As further illustrated in  FIGS.  3 ,  13  and  15   , the strike block  26  may also have an enclosure  44  housing a spring-loaded button  46 . As best illustrated in  FIGS.  4  and  14   , the spring-loaded button  46  has a disk-shaped configuration conducive for sliding back-and-forth within the enclosure  44  between locked and unlocked positions. Specifically in this respect, the spring-loaded button  46  has planar shape that generally tracks the size and shape of the strike block  26 , albeit an externally accessible corrugated tab  48  designed to enhance fictional engagement during hand depressed operation thereof may extend out from one side thereof as illustrated, e.g., in  FIGS.  6 ,  8 , and  13   . Moreover, to an interior thereof, the spring-loaded button  46  may further include an opening  50  formed opposite the corrugated tab  48  that generally tracks the size and shape of a keyed rod-receiving channel  52  therein when the spring-loaded button  46  is depressed within the enclosure  44 . Doing so allows insertion of the extractor rod  30 , as discussed in more detail below. One side of the opening  50  may further include an inwardly projecting latch  54  having a chamfer  55  that forms an inwardly extending ramp that facilitates slide-in reception of the extractor rod  30  into the opening  50  for retainment therein by the spring-loaded button  46 . 
     When in a normal non-use or undepressed position, a spring  56  ( FIG.  56   ) residing in a spring retaining chamber  57  in the strike block  26  ( FIG.  13   ) generally biases the spring-loaded button  46  in a position wherein the latch  54  at least partially resides within the keyed rod-receiving channel  52  and the inwardly extending chamfer  55  at least partially encompasses the extractor rod  30  to prevent return travel out from the keyed rod-receiving channel  52  when the extractor rod  30  is mounted or otherwise engaged with the dual-purpose orthopedic surgery instrument  20 . Also, when in this position, the corrugated tab  48  generally projects out from a side of the strike block  26  for relatively easy engagement and depression thereof. Depressing the spring-loaded button  46  against the internally located spring  56  displaces the latch  54  out from a blocking relationship within the keyed rod-receiving channel  52  to permit movement of the extractor rod  30  out from the dual-purpose orthopedic surgery instrument  20 . That is, when the spring  56  is compressed, the opening  50  in the spring-loaded button  46  may generally align with the keyed rod-receiving channel  52  thereby permitting the extractor rod  30  to be removed therefrom. 
     Insertion may simply involve pushing the extractor rod  30  into the keyed rod-receiving channel  52  and into engagement with the chamfer  55  residing therein. So long as the insertion force is greater than the extension force exerted by the spring  56 , the extractor rod  30  will travel down along the incline of the chamber  55 , thereby causing the spring-loaded button  46  to place a compressive force on the spring  56 . The spring-loaded button  46  is able to move side-to-side within the enclosure  44  to displace the latch  54  by a distance sufficient to allow the extractor rod  30  to pass through the opening  50  and into a cavity  59 . Once the extractor rod  30  reaches the cavity  59  and is no longer in engagement along the incline of the chamfer  55 , the spring  56  is allowed to expand outwardly to relocate the spring-loaded button  46  in the enclosure  44  to a normal closed or locked position whereby the latch  54  at least partially extends out and around the extractor rod  30  to retain the extractor rod  30  within the keyed rod-receiving channel  52 . The extractor rod  30  will remain therein until the external corrugated button  48  is depressed inwardly again compressing the spring  56  within the spring retaining chamber  57  to displace the latch  54  out from generally encompassing the extractor rod  30 . The spring-loaded button  46  may include a slide channel  61  ( FIG.  14   ) having a width sufficient to allow said side-to-side movement of the spring-loaded button  46  within the enclosure  44  to enable the latch  54  to selectively lock and/or unlock the extractor rod  30  within the keyed rod-receiving channel  52 . The strike block  26  may include a pair of coaxially aligned pin retaining apertures  63  that selectively receive a pin therein (not shown) that extends through the slide channel  61  aligned therewith. As such, the pin will only permit the spring-loaded button  46  to move side-to-side in the enclosure  44  a distance approximately that of the width of the slide channel  61  as a result. 
     In an alternative embodiment, the spring-loaded button  46  may include a locking feature similar to that of a pen that retains the spring-loaded button  46  in an open position where the opening  50  remains substantially aligned with the keyed rod-receiving channel  52  when moved a sufficient distance within the enclosure  44 . Here, the spring  56  remains continually depressed without the need to continually depress the spring-loaded button  46 . Pressing the spring-loaded button  46  a second time may disengage or unlock the spring-loaded button  46  so that the spring  56  may bias the spring-loaded button  46  back to the closed position where the latch  54  is able to encompass the extractor rod  30  if in the keyed rod-receiving channel  52 . The process can be repeated depending on whether the extractor rod  30  is to be inserted or removed from the keyed rod-receiving channel  52 . Alternatively, insertion of the extractor rod  30  may require that the surgeon continuously depress the spring-loaded button  46  to maintain the opening  50  in an aligned position with the keyed rod-receiving channel  52 . 
     In one embodiment, the extractor rod  30  may include additional couplings for purposes of being adapted to extract trial components, actual implant components, intramedullary rods, and/or inserts. For instance, the extractor rod  30  may include a tibial extractor  58  formed from one end thereof and a femoral extractor  60  formed from an opposite end thereof. 
     To form the slap hammer  32  by way of engaging the dual-purpose orthopedic surgery instrument  20  with the extractor rod  30 , the surgeon may first insert the tibial extractor  58  in through the elongated channel  28  in the dual-purpose orthopedic surgery instrument  20  and into a bottom channel  62  therein and eventually out through the impactor block  24  by way of the open recess  36  positioned below the bottom channel  62  as illustrated best in the cross-sectional view of  FIG.  12   . Initially, the extractor rod  30  may extend into each of the elongated channel  28  and the bottom channel  62  at an angle, whereby the upper portion of the extractor rod  30  having the femoral extractor  60  formed therewith must be rocked into engagement with the dual-purpose orthopedic surgery instrument  20  along an arrow  64  illustrated in  FIG.  6   . This causes the extractor rod  30  to slide into the keyed rod-receiving channel  52 , thereby displacing the spring-loaded button  46  to permit insertion therein. As illustrated in  FIG.  7   , the recess  36  may include a tapered inner wall  66  having a relatively narrower opening near where the tibial extractor  58  is inserted therein (e.g., immediately below the bottom channel  62 ) after insertion through one of the elongated channels  28 . As such, the tapered inner wall  66  provides additional tolerance out through the bottom of the impactor block  24  for the surgeon to at least somewhat axially displace the extractor rod  30  for purposes of insertion and removal. Once the extractor rod  30  is fully inserted, the spring-loaded button  46  moves within the enclosure  44  back to the normal closed position whereby the latch  54  retains the extractor rod  30  in position and prevents the extractor rod  30  from moving back into the keyed rod receiving channel  52 . 
     Once inserted, the extractor rod  30  is removably constrained between the impactor block  24  and the strike block  26 . Here, the dual-purpose orthopedic surgery instrument  20  is in slidable relation relative to the extractor rod  30 . As illustrated in  FIG.  6   , the femoral extractor  60  is generally positioned above the strike block  26  and the tibial extractor  58  is generally positioned below the impactor block  24 . In one embodiment, the modular impactor head  34  may include an aperture that aligns with the bottom channel  62  and the recess  36  thereby allowing the surgeon to insert the extractor rod  30  into the dual-purpose orthopedic surgery instrument  20  without decoupling the modular impactor head  34  from the impactor block  24 . 
     As illustrated in  FIG.  8   , the extractor rod  30  may further include a generally circumferential stopper  68  outwardly extending about a portion of the extractor rod  30  to form a step or shoulder thereon. The stopper  68  is of a size and shape relatively smaller than the elongated channel  28  to permit slide through reception therein when engaging the extractor rod  30  with the dual-purpose orthopedic surgery instrument, yet of a size and shape relatively larger than the smallest diameter of the impactor block  24  and the strike block  26 . For example, as best illustrated in the cross-sectional view of  FIG.  12   , each of the impactor block  24  and the strike block  26  include a respective set of inwardly projecting shoulders  69 ,  69 ′ having an internal diameter relatively smaller than the outwardly projecting stopper  68 , thereby preventing the dual-purpose orthopedic surgery instrument  20  from sliding off the extractor rod  30 . As such, the surgeon can forcibly slide the dual-purpose orthopedic surgery instrument  20  along the length of the extractor rod  30  between each of the shoulders  69 ,  69 ′ for purposes of using the device as the slap hammer  32  when the stopper  68  contacts one of the respective shoulders  69 ,  69 ′. 
     In an alternative embodiment, the elongated channel  28  may be wider near the middle of the elongated handle  22  and narrower toward the ends thereof, whereby the stopper  68  may be small enough to fit within the relatively wide portion of the elongated channel  28  but not through the narrower portions closer to each of the impactor block  24  and the strike block  26 . The stopper  68  may be integrally formed with the extractor rod  30 , or selectively coupled thereto as a separate component. For example, in an embodiment wherein the stopper  68  and extractor rod  30  are metal, the stopper  68  may be welded to the extractor rod  30 . 
     As illustrated in  FIG.  9   , the extractor rod  30  may have a keyed cross-section, such as a pair of flat sides  72  and a pair of rounded sides  74 . In this respect, the width of the extractor rod  30  between each of the flat sides  72  may be somewhat relatively smaller than the opening formed by the keyed rod-receiving channel  52  to permit slide through engagement therewith. Moreover, the width of the extractor rod  30  between each of the rounded sides  74  may be relatively wider than the keyed rod-receiving channel  52  to prevent insertion therethrough. This helps ensure that the extractor rod  30  engages with the dual-purpose orthopedic surgery instrument  20  in the correct or desired orientation. Moreover, after insertion, the pair of flat sides  72  sit flush against a pair of inner flat surfaces  76  ( FIG.  4   ) within the cavity  59  to prevent rotation of the extractor rod  30  relative to the dual-purpose orthopedic surgery instrument  20  during use. As such, this additional feature provides added stability during use of the dual-purpose orthopedic surgery instrument  20  as the slap hammer  32 . The keyed cross section illustrated in  FIG.  9    may extend substantially along the length of the extractor rod  30 , or along certain sections thereof (e.g., near where the elongated extractor rod  30  would insert through the keyed rod receiving channel  52  into the spring-loaded button  46 ). In alternative embodiments, the extractor rod  30 , bottom channel  62 , and/or stopper  68  may have cross sections that are circular, square, triangular, or other shapes known in the art. 
       FIG.  10    illustrates another example wherein a surgeon may couple the femoral extractor  60  to a femoral trial  78  via a slot  80  therein. The surgeon may then slide the dual-purpose orthopedic surgery instrument  20  along the extractor rod  30  away from the femoral trial  78 , such as along the direction indicated by arrows  82 . The dual-purpose orthopedic surgery instrument  20  may slide along the extractor rod  30  until the shoulder  69 ′ of the strike block  26  contacts the stopper  68 . The force applied by the dual-purpose orthopedic surgery instrument  20  contacting the stopper  68  may create an impulse along the length of the extractor rod  30  that transfers to the femoral trial  78 , thereby pulling the femoral trial  78  in the same direction as the arrows  82 . The surgeon may repeat the process of sliding the dual-purpose orthopedic surgery instrument  20  away from the femoral trial  78 , as is known in the art for the use of a slap hammer, until the femoral trial  78  is extracted from the distal end of a patient femur. Of course, a similar process may be performed with the tibial extractor  58  coupled to a tibial trial to extract the tibial trial from the proximal end of a patient tibia. In alternate embodiments, either end of the extractor rod  30  may couple to insert trials, tibial components, femoral components, intramedullary rods, cut blocks, broaches, or any other implant component and/or surgical instrument known in the art. The tibial extractor  58  and/or the femoral extractor  60  may couple thereto via snap-fit coupling, slide-fit coupling, threaded coupling, or any other method of coupling known in the art. 
     As illustrated in  FIG.  11   , the dual-purpose orthopedic surgery instrument  20  may include a tab  84  (best shown in  FIG.  3   ) that couples to a tibial insert  86 . The tab  84  may generally extend outwardly perpendicular to the longitudinal axis of the elongated handle  22 . The tab  84  may allow the surgeon to seat the tibial insert  86  on a tibial component  88 . The tab  84  may further allow the surgeon to adjust the placement and/or alignment of the tibial insert  86 . Alternatively, the tab  84  may be used to seat, position, and/or align femoral components, tibial components, trial components, or any component that does not need to be impacted into the bone. 
     In an alternative embodiment illustrated in  FIG.  16   , the dual-purpose orthopedic instrument  20  may include an alternative strike block  26 ′ that includes a locking slot  90  ( FIGS.  17 A- 17 B ) configured to allow coaxial pass-through reception of the extractor rod  30  when in an open position, but constrain the extractor rod therein  30  when in a closed or locked position. More specifically in this respect, the alternative strike block  26 ′ houses a movable lever  92  therein actuated by an externally accessible spring-actuated lever button  94 . In  FIG.  17 A , the lever button  94  normally positions the lever  92  at least partially into the locking slot  90  when in a locked position. Here, when the locking slot  90  is in the closed position, the lever  92  obstructs part of the opening formed by the locking slot  90  such that the passable width therein is relatively smaller than the width of the stopper  68  of the extractor rod  30 . As such, while the width of the extractor rod  30  is of a size that permits sliding movement within the locking slot  90  when in this locked position, the width of the stopper  68  is too large to pass therethrough while the lever  92  remains normally positioned therein as illustrated in  FIG.  17 A  by the spring-biased lever button  94 . Accordingly, the lever button  94  must be depressed to open the locking slot  90  to fully insert or remove the extractor rod  30  therefrom. 
     In this respect  FIG.  17 B  illustrates depressing the lever button  94  generally along a directional arrow  96  to spring-actuate pivoting movement of the lever  92  within the alternative strike block  26 ′. When the lever button  94  is fully depressed as illustrated in  FIG.  17 B , the lever  92  pivots completely out from within the locking slot  90  so the lever  92  no longer provides any obstruction therein. Here, the locking slot  90  is now in an open position having a width large enough to allow coaxial pass-through reception or removal of the extractor rod  30  and its relatively larger diameter stopper  68 . When in this position, the extractor rod  30  is no longer constrained within the dual-purpose orthopedic surgery instrument by the stopped  68 , whereby the extractor rod  30  can be inserted and/or removed therefrom. 
     Accordingly, in this embodiment, to form the slap hammer  32  by way of engaging the dual-purpose orthopedic surgery instrument  20  with the extractor rod  30 , the surgeon would first press the lever button  94  to move the lever  92  out of the locking slot  90  and then insert the tibial extractor  58  through the locking slot  90  and out through the impactor block  24 . The open locking slot  90  allows the stopper  68  to pass through the strike block  26 ′ and into the elongated channel  28 . Releasing the button  94  allows the lever  92  to return to the closed position illustrated in  FIG.  17 A  at least partially extending or blocking the locking slot  90 . At this point, as best illustrated in  FIG.  18   , the stopper  68  is located below the strike block  26 ′ and restrained within the elongated channel  28  because the width of the stopper  68  is relatively larger than the width of the bottom channel  62  and the locking slot  90 . As when in this position, the extractor rod  30  is removably constrained between the impactor block  24  and the strike block  26 ′, and the dual-purpose orthopedic surgery instrument  20  is in slidable relation relative to the extractor rod  30  for operation as the slap hammer  32 . After use, the extractor rod  30  may be removed from the dual-purpose orthopedic instrument  20  by pressing the lever button  94  to reopen the locking slot  90  when the lever  92  pivots out from obstruction therein, and sliding the extractor rod  30  out of the locking slot  90  now that the stopper  68  has sufficient clearance to pass through the locking slot  90 . 
     Lastly, an exemplary method of using the dual-purpose orthopedic surgery instrument  20  may include coupling the modular impactor head  34  to the impactor interface  25  of the impactor block  24 , locating the modular impactor head  34  on the femoral trial  78 , hitting the strike surface  42  with a hammer and impacting the femoral trial  78  into the distal end of a patient femur. The surgeon may then decouple the modular impactor head  34  and insert the extractor rod  30  in through the elongated channel  28  and into the bottom channel  62  and the recess  36 , then tilt the extractor rod  30  into the keyed rod-receiving channel  52  (and optionally depressing the spring-loaded button  46  to facilitate opening the same), and then reposition the spring-loaded button  46  to lock the extractor rod  30  to the dual-purpose orthopedic surgery instrument  20 . The femoral extractor  60  may then couple to the femoral trial  78  and the surgeon may slide the dual-purpose orthopedic surgery instrument  20  along the length of the elongated channel  28  for use as the slap hammer  32 . Sliding the dual-purpose orthopedic surgery instrument  20  along the extractor rod  30  creates an impulse when the stopper  68  collides with either of the shoulders  69 ,  69 ′. The surgeon may repeat the sliding process until the femoral trial  78  is extracted from the distal end of the patient femur. The surgeon may then remove the extractor rod  30 , couple the modular impactor head  34  to the impactor block  24 , locate the modular impactor head  34  on an actual femoral implant component, and apply a force to the strike surface  42  to impact the actual femoral implant component into the distal end of the patient femur. Allowing the surgeon to perform all of these processes with a single dual-purpose orthopedic surgery instrument  20  reduces the number of individual devices required by the procedure and streamlines knee arthroplasty and/or knee revision. 
     Although several embodiments have been described in detail for purposes of illustration, various modifications may be made without departing from the scope and spirit of the invention. Accordingly, the invention is not to be limited, except as by the appended claims.