Abstract:
An apparatus for bone milling includes a housing defining a first opening, a second opening opposite the first opening, and a linear passage from the first opening to the second opening. The linear passage has a first surface with third opening there through and a second surface transverse to the first surface. A rotatable cutting member is insertable through the third opening to partially block the linear passage. The rotatable cutting member is positioned at a distance from the second surface of the linear passage corresponding to a predetermined bone chip size.

Description:
CROSS-REFERENCE TO RELATED APPLICATION  
       [0001]     This application is a Continuation-in-Part of and claims priority to U.S. Continuation-in-Part Patent Application Ser. No. 11/051,882, filed Feb. 4, 2005, entitled BONE CRUSHER AND METHOD FOR BONE CRUSHING, which Application claims priority from U.S. Utility Patent Application Ser. No. 10/961,573, filed Oct. 08, 2004, entitled BONE CRUSHER AND METHOD FOR BONE CRUSHING, which application is related to and claims priority to U.S. Provisional Patent Application Ser. No. 60/542,209, filed Feb. 05, 2004, entitled BONE CRUSHER AND METHOD THEREFORE, the entirety of all which are incorporated herein by reference. 
     
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT  
       [0002]     n/a  
       FIELD OF THE INVENTION  
       [0003]     The present invention relates to an orthopedic medical device and method, in particular to a method and device for bone cutting for use during orthopedic surgery.  
       BACKGROUND OF THE INVENTION  
       [0004]     Orthopedic surgery often requires the infusion of a slurry comprised of blood and crushed bone into a surgical site to promote healing and recovery after an injury. The crushed bone in the slurry is ground and pulverized from a larger bone specimen using a bone grinder that reduces the larger specimen into crushed bone particles. Bone mills allow patients to have their own bone particles implanted when there is a preference towards using an autograft to alleviate the possibility of rejection or infection at the surgical site. The surgeon can utilize the bone particles and the resulting slurry to repair bone defects and perform bone augmentation.  
         [0005]     Existing bone mills are large, expensive devices which are cumbersome to use and clean and further require re-sterilization at the end of each procedure. Such re-sterilization takes the form of expensive and time consuming gas sterilization or autoclave sterilization. In the case of gas sterilization, the nature of the sterilization process makes the bone mills available for use only once in a 24-hour period. When using an autoclave sterilization process, the bone mills can be sterilized and available for reuse in less than a 24-hour period, however, the bone mills are not immediately available. The resulting period required to re-sterilize the bone mills nevertheless increases the time which necessarily passes between procedures, thereby decreasing operating room and surgical efficiency. Further, the porous nature of blades commonly found in bone mills facilitates the retention of bone particles. The blade porosity hampers the effectiveness of the cleaning process, which furthers the possibility of contamination during subsequent use of the bone mill.  
         [0006]     Moreover, existing bone mills are typically powered devices that require an external means for driving the mill, such as a pressurized air source or an electrical motor. Additionally, existing mills may only have the capability to produce a single size of crushed bone particles. As such, a surgical suite needs to have multiple devices to provide crushed bone at different sizes, which greatly increases the cost of having bone-milling capabilities. Otherwise, a surgeon is disadvantageously forced to use crushed bone having a size either too large or too small for a particular surgical procedure, resulting in potential difficulties during an orthopedic procedure.  
         [0007]     It is therefore desirable to have an inexpensive bone mill which is easy to sterilize and can further be adapted to create bone chips of different sizes. It is also desirable to have a bone mill which can be manually operated without the assistance of external power sources.  
       SUMMARY OF THE INVENTION  
       [0008]     The present invention advantageously provides a method and system for a bone mill that is easy to sterilize, adapted to create bone chips of different sizes, and operated manually without the need for external power sources. As such, the present invention reduces the overall cost of orthopedic procedures requiring a crushed bone slurry, does not adversely impact the surgical suite turn-over time and provides a high yield of usable bone particles having relatively uniform dimensions.  
         [0009]     In accordance with the present invention, an aspect provides an apparatus for bone milling in which a housing defines a first opening, a second opening opposite the first opening, and a linear passage from the first opening to the second opening. The linear passage has a first surface with third opening there through and a second surface transverse to the first surface. A rotatable cutting member is insertable through the third opening to partially block the linear passage. The rotatable cutting member is positioned at a distance from the second surface of the linear passage corresponding to a predetermined bone chip size.  
         [0010]     In accordance with another aspect, the present invention provide an apparatus for bone milling in which a housing defines a first opening, a second opening opposite the first opening, and a linear passage from the first opening to the second opening. A rotatable cutting member traverses at least a portion of the linear passage. An actuator element defines a first end, a second end opposite the first end and a channel extending from the first end to the second end. The channel is adapted to contain at least a portion of the rotatable cutting member therein. The first end is removably coupled to the housing and the rotatable cutting member is removable from the channel through the second end of the actuator element while the actuator element remains coupled to the housing.  
         [0011]     According to still another aspect a method for milling bone is provided in which bone to be milled is inserted into a bone milling apparatus. The apparatus has a housing defining a first opening, a second opening opposite the first opening, and a linear passage from the first opening to the second opening, the linear passage having a first surface with third opening there through and a second surface transverse to the first surface. The apparatus also has a rotatable cutting member insertable through the third opening to partially block the linear passage. The rotatable cutting member is positioned at a distance from the second surface of the linear passage corresponding to a predetermined bone chip size. The apparatus further includes a plunger and a milled material receptacle removably coupled to the second opening. The plunger is placed in the first opening of the apparatus to force the bone towards the rotatable cutting member. The actuator element is operated to rotate the rotatable cutting member, thereby milling the bone. The milled material is collected in the milled material receptacle. In addition, the present invention provides for a bone mill which can be coupled to a powered device through an intermediary adapter to eliminate the need to actuate the bone mill manually. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0012]     A more complete understanding of the present invention, and the attendant advantages and features thereof, will be more readily understood by reference to the following detailed description when considered in conjunction with the accompanying drawings wherein:  
         [0013]      FIG. 1  illustrates the internal and external features of a bone mill in accordance with the present invention;  
         [0014]      FIG. 2  depicts an exploded view of a bone mill in accordance with the present invention;  
         [0015]      FIG. 3  shows added features of a bone mill in accordance with the present invention;  
         [0016]      FIG. 4  shows a perspective view of an alternative embodiment of a bone mill in accordance with the present invention;  
         [0017]      FIG. 5  illustrates a side view of an alternative embodiment of a bone mill in accordance with the present invention;  
         [0018]      FIG. 6  depicts a rear view of an alternative embodiment of a bone mill in accordance with the present invention;  
         [0019]      FIG. 7  shows a front view of an alternative embodiment of a bone mill in accordance with the present invention;  
         [0020]      FIG. 8  illustrates a top view of an alternative embodiment of a bone mill in accordance with the present invention;  
         [0021]      FIG. 9  depicts a bottom view of an alternative embodiment of a bone mill in accordance with the present invention;  
         [0022]      FIG. 10  shows a cross-sectional view of an alternative embodiment of a bone mill in accordance with the present invention;  
         [0023]      FIG. 11  depicts a perspective view of a mill body of an alternative embodiment of a bone mill in accordance with the present invention;  
         [0024]      FIG. 12  illustrates a cross-sectional view of a mill body of an alternative embodiment of a bone mill in accordance with the present invention;  
         [0025]      FIG. 13  shows an additional cross-sectional view of a mill body of an alternative embodiment of a bone mill in accordance with the present invention;  
         [0026]      FIG. 14  illustrates a perspective view of an actuator element of an alternative embodiment of a bone mill in accordance with the present invention;  
         [0027]      FIG. 15  depicts a cross sectional view of an actuator element of an alternative embodiment of a bone mill in accordance with the present invention;  
         [0028]      FIG. 16  shows a side view of an actuator element of an alternative embodiment of a bone mill in accordance with the present invention;  
         [0029]      FIG. 17  shows an actuator cap of an alternative embodiment of a bone mill in accordance with the present invention;  
         [0030]      FIG. 18  illustrates a cross-sectional view of an actuator cap of an alternative embodiment of a bone mill in accordance with the present invention;  
         [0031]      FIG. 19  illustrates a perspective view of a coupling element of an alternative embodiment of a bone mill in accordance with the present invention;  
         [0032]      FIG. 20  depicts a cross-sectional view of a coupling element of an alternative embodiment of a bone mill in accordance with the present invention;  
         [0033]      FIG. 21  shows a plunger of an alternative embodiment of a bone mill in accordance with the present invention;  
         [0034]      FIG. 22  depicts a receptacle of an alternative embodiment of a bone mill in accordance with the present invention;  
         [0035]      FIG. 23  illustrates a cross-sectional view of a receptacle of an alternative embodiment of a bone mill in accordance with the present invention;  
         [0036]      FIG. 24  shows an expanded view of an assembly of a bone mill in accordance with the present invention;  
         [0037]      FIG. 25  depicts a modified actuator cap and an adapter of an alternative embodiment of a bone mill in accordance with the present invention;  
         [0038]      FIG. 26  shows an additional view of the modified actuator cap and adapter of  FIG. 25  in accordance with the present invention;  
         [0039]      FIG. 27  illustrates a cross-sectional view of the modified actuator cap of  FIG. 25  in accordance with the present invention; and  
         [0040]      FIG. 28  shows a cross-sectional view of the modified actuator cap coupled with the adapter of  FIG. 25  in accordance with the present invention.  
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0041]     The present invention provides a disposable, hand-operated bone mill that accommodates cutting plates to produce bone chips of a selected size based on a blade installed in the mill body  10 . Referring now to  FIG. 1 , an exemplary embodiment of the present invention includes a bone mill having a mill body  10  that defines a first opening  12 , a second opening  14 , and a linear passage  15  that extends from the first opening  12  to the second opening  14 . The mill body  10  further includes a rotatable cutting member  18  coupled to an actuator element  20 , as shown in  FIG. 2 . Further, the mill body  10  can include a third opening  16  through which the rotatable cutting member  18  couples to the actuator element  20 . The first opening  12  can be adapted to receive a plunger  22 , and a receptacle  24  can be removably coupled to the second opening  14 .  
         [0042]     The first opening  12  provides an access area into which a suitably sized bone portion can be inserted for milling. First opening  12  can be of any shape, whether having a circular or rectangular cross-section, so long as a bone specimen of a particular dimension can pass through first opening  12  and into the mill body  10  for subsequent milling. First opening  12  can be adapted to receive the plunger  22 , which is used to aid in forcing a bone specimen further into the linear passage  15  towards the rotatable cutting member  18 . The plunger  22  can be of any shape or orientation, so long as it is capable of being inserted into the first opening  12 , and includes at least one depressing surface for contacting a bone specimen in the mill body  10  and forcing it further into the linear passage  15 .  
         [0043]     The second opening  14  provides an exit area from which milled bone particles may be dispensed. Second opening  14  can be of any shape, whether having a circular or rectangular cross-section, so long as it is of sufficient width to allow milled bone particles to descend out of the opening and into the receptacle  24 . Receptacle  24  can be removably coupled to the second opening  14  through any suitable affixation means, including affixation through the use of a threaded interlocking surface, a snap-on mechanism, or the like. Additionally, receptacle  24  may be affixed either to an exterior surface or interior surface of the mill body  10  in the vicinity of the second opening  14  in order to capture the dispensed milled bone material. The receptacle  24  generally defines an interior cavity accessible by a single opening to receive dispensed milled material, and may be of any suitable shape as to be removably coupled to the second opening  24  of the mill body  10 .  
         [0044]     The rotatable cutting member  18  preferably includes a cylindrical, rod-shaped element having a substantially solid cross-section, and further has at least one cutting element or cutting groove disposed on its outer periphery. Additionally, the rotatable cutting element  18  has a diameter that is less than one-half of an inch, and is positioned in the mill body  10  such that the rotatable cutting member substantially fills or occludes a portion of the linear passage  15 . By occluding or filling a portion of the linear passage  15 , a bone specimen inserted in the bone mill is ensured direct contact with the rotatable cutting member  18  to further guarantee that only bone chips of a particular dimension proceed further down the linear passageway  15 , where they eventually descend into the receptacle  24 . An example of a suitable embodiment of the rotatable cutting member  18  is a precision milling bit (for instance, part #233049 from CONTROX®). The rotatable cutting member is preferably constructed from a highly durable steel or metal material that will not dull easily during repeated uses of the bone mill. Rotatable cutting member  18  can include a spiral-oriented plurality of grooves which present multiple cutting edges for reducing a bone specimen into bone chips or particles. The cutting edges of the cutting member can be positioned to cut into a bone specimen at approximately a 45-degree angle when the bone mill is in use, which provides a maximized mechanical advantage, reduces the amount of torque necessary to effectively mill a bone specimen, and eases the overall use of the bone mill. Moreover, the cutting edges of the cutting member may include jagged or saw-tooth edges which perforate or otherwise cut into the bone on a micro level, delivering particles of the desired size and resulting in a more efficient milling process.  
         [0045]     While an exemplary size of the bone particles produced by the rotatable cutting member  18  ranges from one-eighth (⅛) of an inch to approximately three-sixteenths ( 3/16) of an inch, the measurements and dimensions of the cutting grooves located on the rotatable cutting member may be modified or characterized in order to produce bone chips of an alternatively predetermined size.  
         [0046]     Rotatable cutting member  18  is coupled to an actuator element  20  by any suitable means of affixation including a bolt, screw, lock ring, or the like. Actuator element  20  provides the mechanical driving means to rotate the rotatable cutting member  18 . The bone mill is preferably manually driven, only requiring the hand strength of a single individual. To ease the use of the bone mill, the actuator element  20  can be in the form of a knob or handle having a diameter or width that is significantly larger than the diameter or width of the rotatable cutting member  18 . The size ratio between the actuator element  20  and the rotatable cutting member  18  provides a mechanical advantage for the user and decreases the force that needs to be applied to the actuator element  20  in order to create sufficient force in the rotatable cutting member  18  to successfully reduce a bone specimen into particles of a desired size.  
         [0047]     The linear passage  15  provides a direct pathway in which a bone specimen can descend directly through the first opening  12 , through the rotatable cutting member  18 , and outward from the second opening  14 . The linear passage  15  can have any virtually any shape or orientation, whether being a circular or rectangular cross-section, so long as the width is sufficient to receive a bone specimen and allow the specimen to descend through the mill body  10 . The linear passage  15  can further include a first region  26  having a first width and a second region  28  having a second width. The first width of the first region  26  can be larger than the second width of the second region  28  so as to accommodate a larger bone specimen, while the second region need only be of sufficient width to allow the milled particles to descend downward to the receptacle  24 . The rotatable cutting member  18  can be positioned such that at least a portion of the rotatable cutting member  18  intersects at least a portion of the first region  26  and at least a portion of the second region  28 . Placing the rotatable cutting member  18  in such a position can ensure that only milled bone particles of a particular size can pass through to the second region  28  of the linear passage  15 , while maintaining location of the larger bone specimen within the first region  26 . Alternatively to having a first and second region, the linear passage can have a single, uniform width, or a plurality of widths, so long as a bone specimen to be milled comes into contact with the rotatable cutting member prior to exiting the mill body  10 .  
         [0048]     As shown in  FIG. 3 , the bone mill can further include a funnel  30  and syringe  32 . The funnel  30  can be removably coupled to the receptacle  24  when a desired amount of milled bone has been collected. The receptacle  24  is uncoupled from the mill body  10 , and is then coupled to the funnel  30  through a mechanism similar to that which coupled the receptacle  24  to the mill body  10 , whether by the use of a threaded interlocking surface, a snap-on mechanism, or the like. Upon coupling the receptacle  24  to the funnel  30 , the milled contents in the receptacle can be transferred into the syringe  32  for direct insertion to a surgical site. By coupling the funnel  30  directly to the receptacle  24 , a user can ensure that no milled contents are wasted or lost when transferring the milled bone from the bone mill to the eventual surgical site.  
         [0049]     In an exemplary use prior to a medical procedure, a bone specimen to be milled is inserted into the first opening  12  of the mill body  10 . The plunger  22  is then placed into contact with the bone specimen as it resides in the first region  26  of the linear passage  15  in the area above the rotatable cutting member  18 . The actuator element  20  is then manually turned, which, in turn, rotates the rotatable cutting member  18 . While turning the actuator element  20 , the user can depress the plunger, thereby forcing the bone specimen towards and into contact with the rotatable cutting member. As the user continues to depress the plunger and turn the actuator element, the bone specimen will be reduced to bone particles of a desired size, which then descend through the second region  28  of the linear passage  15  and into the receptacle  24  that is removably coupled to the second opening  14  of the mill body.  
         [0050]     In an alternative exemplary embodiment, as shown in  FIGS. 4 through 24 , a bone mill  40  includes a mill body  42 , an actuator element  44 , an actuator cap  46 , a plunger  48 , and a receptacle  50 . In addition, as illustrated by  FIG. 10 , the bone mill  40  also includes a rotatable cutting member  52  and a coupling element  54 .  
         [0051]     Now referring to  FIGS. 11 through 13 , the mill body  42  defines a first opening  56 , a second opening  58 , and a linear passage  60  that extends from the first opening  56  to the second opening  58 . The first opening  56  can be adapted to receive the plunger  48 , and the receptacle  50  can be removably coupled to the second opening  58 . The mill body  42  may also include a plurality of ridges  62  distributed about a portion of an exterior surface of the mill body  42 , as well as one or more coupling slots  64 . The ridges  62  increase the ability of the mill body  42  to be gripped when the bone mill  40  is in use, while the coupling slots  64  provide for subsequent assembly of the bone mill  40 .  
         [0052]     The mill body  42  further includes a third opening  66  through which the rotatable cutting member  52  may pass through as to partially fill or occlude a portion of the linear passage  60 . The linear passage  60  includes a first region  68  descending from the first opening  56  towards an area where the linear passage  60  intersects with the third opening  66 , and thus, where the rotatable cutting member  52  would be located within the linear passage  60 . Further, the linear passage  60  includes a second region  70  descending from the first region  68  towards the second opening  58 .  
         [0053]     As shown in  FIG. 14 , the rotatable cutting member  52  is preferably a rod-like element having grooves or cutting projections  78  disposed about an outer surface of the cutting member. Rotatable cutting member  52  can include a spiral-oriented plurality of grooves which present multiple cutting edges for reducing a bone specimen into bone chips or particles. The rotatable cutting member  52  may be removably coupled to the actuator element  44 , where the actuator element  44  provides the mechanical driving means to rotate the rotatable cutting member  52 .  
         [0054]     Now referring to  FIGS. 15 and 16 , the actuator element  44  may be in the form of a handle or knob having a diameter significantly larger than the diameter of the rotatable cutting member  52  in order to provide a mechanical advantage which reduces the amount of force necessary in order to mill bone material. The actuator element  44  can have a cutting member channel  72  extending through the actuator element  44  which allows the rotatable cutting member  52  to be inserted, and thus coupled, to the actuator element  44 . The channel  72  extends through the entire width of the actuator element  44 , although the circumference of the channel  72  may vary in order to mechanically engage the rotatable cutting member  52 . In addition, the actuator element  44  can have a mating groove  74  extending around a circumference of a surface of the actuator element  44 .  
         [0055]     The bone mill  40  can also include the actuator cap  46 , as shown in  FIGS. 17 and 18 . The actuator cap  46  has a generally disc-like shape and may further include a plurality of protrusions  76  adapted to removably couple to the actuator.  
         [0056]     As shown in  FIGS. 19 and 20 , the bone mill  40  may include the coupling element  54 . The coupling element  54  is an essentially ring-like structure that can include first and second projections  78  disposed about an outer surface. Additionally, the coupling element  54  includes one or more prongs  80  extending from the body of the coupling element  54 , where the prongs  80  have a raised shoulder  82  at a single end of the prong.  
         [0057]     The plunger  48  is provided as illustrated in  FIG. 21 . The plunger  48  can be adapted to any shape which allows for insertion of the plunger  48  into the first opening  56  of the mill body  42  to aid in forcing a bone specimen into the linear passage  60  and towards the rotatable cutting member  52 .  
         [0058]     Now referring to  FIGS. 22 and 23 , the receptacle  50  defines a cavity  84  for receiving milled bone material when coupled to the mill body  42 . In addition to capturing dispensed bone material, the receptacle  50  may also provide a support function for stabilizing the bone mill  40  when the mill is placed on a surface for subsequent use. For example, the receptacle  50  can include a first end  86  which couples to the mill body  42 , where the first end  86  includes an opening into the cavity  84  for deposit of milled bone material. The receptacle  50  also includes a second end  88 , opposite the first end  86 , which has a larger width than the first end  86 , thereby increasing a surface area of the receptacle  50  and increasing the stability of the bone mill  40  when placed on a surface. The receptacle  50  may include an alignment feature, in the form of a groove or raised projection to aid in ensuring the proper alignment of the cavity  84  and the second opening  58  in the mill body  42  when the receptacle  50  is coupled to the mill body  42 .  
         [0059]     As shown in  FIG. 24 , in an exemplary assembly and use of the bone mill  40  of the present invention, the mill body  42  is mated with the coupling element  54 . The first and second projections  78  of the coupling element  54  are inserted into the coupling slots  64  of the mill body  42 , as to secure the coupling element  54  to the mill body  42 . Subsequently, the actuator element  44  is mated with the coupling element  54 , and thus, to the mill body  42 . The shoulders  82  extending from the prongs  80  of the coupling element  54  engage the mating groove  74  of the actuator element  44  in such a way that the actuator element  44  is firmly coupled to the coupling element  54  and the mill body  42 , yet retains the ability to rotate in place.  
         [0060]     Upon coupling the actuator element  44  to the mill body  42 , the rotatable cutting element is inserted through the actuator element  44  and into the cutting member channel  72 . Once the rotatable cutting member  52  is placed in the channel  72 , a portion of the rotatable cutting member  52  will protrude out of the actuator element  44 , through the third opening  66  of the mill body  42 , and into a portion of the linear passage  60 .  
         [0061]     To prevent the rotatable cutting member  52  from displacing during use of the bone mill  40 , the actuator cap  46  is then coupled to the actuator, thus enclosing the exposed interior of the actuator element  44 , and preventing the rotatable cutting element from falling out. Because of the removable nature of the actuator cap  46  and the rotatable cutting member  52 , cutting members having different dimensions or features may be interchanged without disassembling the entire bone mill  40 , allowing bone chips of varying, predetermined sizes to be created rather quickly and effortlessly. The assembled bone mill  40 , actuator element  44 , rotatable cutting member  52 , and actuator cap  46  may then be coupled to the receptacle  50  and placed on a surface, employing the increased surface area, and thus stability, of the receptacle  50 . The desired material to be milled is then placed in the first opening  56  of the mill body  42 , and forced down the linear passage  60  towards the rotatable cutting member  52  by the plunger  48 .  
         [0062]     While the measurements and dimensions of the cutting grooves located on the rotatable cutting member  52  may be modified or characterized in order to produce bone chips of an alternatively predetermined size, characteristics of bone chips created by the bone mill  40  may further be manipulated by modifying the spacing between an outer edge of the rotatable cutting member  52  and a surface of the linear passage  60 . As a result, the spacing between the rotatable cutting member  52  and a surface of the linear passage  60  define a single-stage milling assembly capable of producing bone chips of a desired size without the need for additional cutting members to produce intermediate-sized bone chips for subsequent milling.  
         [0063]     For example, as may be readily observed in  FIG. 12 , in the mill body  42 , if the first region  68  of the linear passage  60  has a first width, and the rotatable cutting member  52  has a first diameter that is smaller than the first width, then there would be a space between a surface of the linear passage  60  and the rotatable cutting member  52  equal to the difference between the first width  54  and the first diameter  56 . Thus, the spacing between the rotatable cutting member  52  and a surface of the linear passage  60  would physically prevent any bone chips having a size greater than that spacing from passing about the rotatable cutting element and descending through the linear passage  60 . As a result, by modifying the spacing between the rotatable cutting member  52  and a surface of the linear passage  60 , for example by interchanging rotatable cutting members having different diameters, bone chips of a predetermined size may be created.  
         [0064]     In an alternative embodiment, the bone mill of the present invention can be coupled to a powered tool or drive source element to facilitate the milling process rather than operating the bone mill manually. Now referring to  FIGS. 25 through 28 , the bone mill may further include an actuator cap  90  adapted to removably couple to the actuator element  20 . The actuator cap  90  has a generally disc-like shape as described previously, however, for the alternative power-driven embodiment of the bone mill, the actuator cap further defines an adaptor receiving impression  92  on a surface of the cap. The adapter receiving impression  92  provides an indented surface shaped to receive and couple to an adapter  94 .  
         [0065]     The adapter  94  is an intermediary element which serves to couple the actuator cap  90  and thus the bone mill, to a drive source element (not shown), such as a power drill, rotary tool, or other powered device having a tool-receiving portion for engaging drill bits or other elements. The adapter  94  defines a first end  96  coupleable with the adapter receiving impression  92  of the actuator cap  90 , and a second end  98  which can be engaged by the particular drive source element. Both the first and second ends of the adapter  94  can include a myriad of shapes or characteristics to effectively implement the drive source element and thus power the bone mill. As merely an illustrative example, the first end  96  of the adapter  94  may define a protruding element having a plurality of surfaces  97 ,  97 ′ angled sharply from one another in order to securely frictionally engage the actuator cap. The surfaces  97 ,  97 ′ provide a large area for contacting the walls of the adapter receiving impression  92  of the actuator cap  90  as to reduce the likelihood that the adapter  94  rotates within the actuator cap  90 , thereby preventing the walls of the cap becoming stripped or worn down. The second end  98  of the adapter may define a plurality of protrusions having varying diameters or widths as to conform to the tool-receiving portion of the drive source element.  
         [0066]     In an exemplary use of the features described above, the actuator cap  90  having the adapter receiving impression is coupled to the actuator  20  of the bone mill. The adapter  94  is engaged with the drive source element by coupling the second end  98  of the adapter with the tool-receiving portion of the drive source element. The drive source element and the adapter  94  are then positioned proximate the bone mill as to engage the first end  96  of the adapter with adapter receiving impression  92  of the actuator cap  90 . Once the adapter  94  is suitably coupled with the actuator cap  90 , the drive source element can be turned on or triggered to provide the turning force required to operate the bone mill and thus process milled bone material as discussed above.  
         [0067]     Through the use of the adapter  94  and modified actuator cap  90 , the bone mill can be integrated with automated power tools that are already present in the operating room. As such, there is no need to provide an additional tool or element to power the bone mill, and the bone mill can further retain its compact size and portability as there is no integral motor or bulky accessories needed to implement the bone mill as a powered device.  
         [0068]     While it has been described that the actuator cap includes the adapter receiving impression in order to couple the bone mill to a powered drive source, such coupling could also be achieved by directly including a feature similar to the receiving impression in the actuator itself. Subsequently, a suitable adapter could be coupled directly to the actuator in order to engage a powered drive source.  
         [0069]     It will be appreciated by persons skilled in the art that the present invention is not limited to what has been particularly shown and described herein above. In addition, unless mention was made above to the contrary, it should be noted that all of the accompanying drawings are not to scale. A variety of modifications and variations are possible in light of the above teachings without departing from the scope and spirit of the invention, which is limited only by the following claims.