Patent Publication Number: US-2007100364-A1

Title: Compact lancing apparatus

Description:
BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention relates, in general, to medical devices and systems and, in particular, to lancing devices and associated systems.  
      2. Description of the Related Art  
      A variety of medical conditions, such as diabetes, call for the monitoring of an analyte concentration (e.g., glucose concentration) in a blood, interstitial fluid or other bodily fluid sample. Typically, such monitoring requires the extraction of a bodily fluid sample from a target site (e.g., a dermal tissue target site on a user&#39;s finger). The extraction (also referred to as “expression”) of a bodily fluid sample from the target site generally involves lancing the dermal tissue target site with a lancing device and then expressing the bodily fluid sample from the lanced site.  
      Conventional lancing devices typically have a rigid housing and a lancet that can be armed (also referred to as “primed”) and launched (also referred to as “fired”) so as to protrude from one end of the lancing device. For example, conventional lancing devices can include a lancet that is mounted within a rigid housing such that the lancet is movable relative to the rigid housing along a longitudinal axis thereof. Typically, the lancet is spring loaded and launched, upon release of the spring, to penetrate (i.e., “lance”) a target site (e.g., a dermal tissue target site). A biological fluid sample (e.g., a whole blood sample or interstitial fluid (ISF) sample) can then be expressed from the penetrated target site for collection and analysis. Conventional lancing devices are described in, for example, U.S. Pat. No. 5,730,753 to Morita, U.S. Pat. No. 6,045,567 to Taylor et al. and U.S. Pat. No. 6,071,250 to Douglas et al., each of which is incorporated fully herein by reference.  
      The lancing of a dermal tissue target site by a conventional lancing device can be unduly painful for several reasons. First, post-launching recoil can cause a lancet to re-penetrate a target site, albeit at a site slightly skewed point with respect to the original lancet penetration point. Such post-launching recoil can, therefore, result in unintentional multiple lancing and an increase in pain. Second, conventional lancing devices may rely on the spring constant of a lancing spring to define a lancet&#39;s penetration depth. However, over time the spring constant may change, thus detrimentally altering the penetration depth. Third, a sudden motion-based impulse emanating from the lancing device housing (i.e., a side-effect of launching) may be noticed by a user. The anticipation of such impulses may be disconcerting to the user.  
      Moreover, conventional lancing devices can be large and cumbersome to use. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      A better understanding of the features and advantages of the present invention will be obtained by reference to the following detailed description that sets forth illustrative embodiments, in which the principles of the invention are utilized, and the accompanying drawings, in which like numerals represent like elements, of which:  
       FIG. 1  is a simplified perspective view of a lancing apparatus according to an exemplary embodiment of the present invention;  
       FIG. 2  is simplified cross-sectional view of the lancing apparatus of  FIG. 1 ;  
       FIG. 3  is a simplified perspective view of a portion of the lancing apparatus of  FIG. 1 ;  
       FIG. 4  is a simplified side view of a connector that can be used with embodiments of lancing apparatuses and analyte monitoring systems according the present invention;  
       FIG. 5  is a simplified side view of the connector of  FIG. 4  gripping an integrated medical device;  
       FIG. 6  is a simplified perspective, cut-away view of the connector and integrated medical device of  FIG. 5 ;  
       FIGS. 7, 8 ,  9  and  10  are simplified perspective and cut-away views of the lancing apparatus of  FIG. 1  in use, with arrows A, A′ and A″ indicating movement of a linkage arm of the lancing apparatus;  
       FIG. 11  is a simplified perspective view of an analyte monitoring system according to an exemplary embodiment of the present invention with a lid of the analyte monitoring system in an open position (i.e., a first position);  
       FIG. 12  is a simplified perspective and cut-away view of a medical device package containing an integrated medical device as can be employed with embodiments of the present invention;  
       FIG. 13  is a simplified perspective view of the analyte monitoring system of  FIG. 11  depicting the lid in an open position and a medical device package being inserted into a lancing apparatus of the analyte monitoring system;  
       FIG. 14  is a simplified perspective view representing a portion of  FIG. 13 ;  
       FIG. 15  is a simplified perspective view of the lid and lancing apparatus of the monitoring system of  FIG. 11  depicting the lid in a closed position (i.e., a second position); and  
       FIG. 16  is a simplified perspective view of the analyte monitoring system of  FIG. 11  in use in the hand (H) of a user. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
      As is described in more detail below with respect to specific embodiments illustrated in the  FIG. 1 , lancing apparatuses according to embodiments of the present invention include an inner housing, a firing mechanism, a lancing mechanism and a linkage arm. The firing mechanism is configured for producing a firing force in a first direction. The lancing mechanism is configured for delivering a lancing force in a second direction with the second direction being toward a target site and in opposition to the first direction. The linkage arm is pivotably attached to the housing and has first and second ends engaged to the firing and lancing mechanisms, respectively. During use, pivoting of the linkage arm converts the firing force in the first direction into the lancing force in the opposing second direction.  
      Lancing apparatus according to embodiments of the present invention are beneficially compact and relatively simple in construction. In addition, post-launching recoil is minimized by the lancing direction being in opposition to the direction of the firing force provided by the firing mechanism, thus acting to reduce pain associated with uncontrolled recoil. In addition, the opposing lancing and firing forces minimize detrimental effects of motion-based linear impulses emanating from the lancing apparatus by transferring such impulses to a housing, rather than to a target site on a user. Furthermore, lancing apparatus according to the present invention can be configured such that momentum in the second direction associated with the lancing force is essentially equal to momentum in the first direction associated with the firing force, thereby also minimizing the detrimental effects of motion-based linear impulses.  
       FIG. 1  is a simplified perspective view of a lancing apparatus  100  for lancing a target site (e.g., a dermal tissue target site on a user&#39;s fingertip) according to an exemplary embodiment of the present invention.  FIG. 2  is a simplified cross-sectional view of lancing apparatus  100  and  FIG. 3  is a simplified perspective view of a portion of lancing apparatus  100 .  
      Referring to  FIGS. 1, 2  and  3 , lancing apparatus  100  includes an inner housing  102 , a firing mechanism  104 , a lancing mechanism  106 , a linkage arm  108  and a priming mechanism  110 . Inner housing  102  includes a first outer surface  112 , a second outer surface  114  (with windows  115  therethrough, depicted in  FIG. 15  only), an inner surface  116 , an inner surface protrusion  118 , a guide rail  120 , a cavity  122  and an opening  123 .  
      Firing mechanism  104  is configured for producing, during use of lancing apparatus  100 , a firing force in a first direction as described in more detail below. Firing mechanism  104  includes a casing  124  (with casing distal end  126 , casing proximal end  128  and casing cavity  130 ), a firing spring  132 , a trigger button  134  and a trigger spring  136 .  
      Lancing mechanism  106  is configured for delivering a lancing force in a second direction during use of lancing apparatus  100  with the second direction being toward the target site and essentially in opposition to the first direction of the firing force. One skilled in the art will recognize that the firing and lancing forces have associated therewith a firing momentum and a lancing momentum, respectively, due to the mass of moving components of the firing and lancing mechanisms. Moreover, since the second direction is essentially in opposition to the first direction, the lancing momentum is essentially in opposition to the firing momentum. If desired to minimize motion-based linear impulses, the mass of firing and lancing mechanism moving components can be predetermined such that the lancing momentum and firing momentum are essentially equal.  
      Lancing mechanism  106  includes a lancing depth adjustor  138 , a holder  140 , a retraction spring  142  (with retraction spring first end  144  and retraction spring second end  146 ), a rod  148  (with rod first end  150  and rod second end  152 ), a retraction spring stop  154 , and stop  156 . In addition, lancing depth adjustor  138  includes a stepped surface  158 , a cap  160  and a depth adjustor spring  162 .  
      Linkage arm  108  includes pivot  164  and is pivotably attached to inner housing  102  and by pivot  164 . Linkage arm  108  also includes an extension  166 , a catch  168 , a linkage arm pin  170 , a depth adjustor engaging feature  172 , a first end  174  and a second end  176 . As explained in detail herein, first end  174  is engaged with firing mechanism  104  and second end  176  is engaged with lancing mechanism  106 . Moreover, linkage arm  108  is configured to convert a firing force in the first direction (see arrow D 1  in  FIG. 2 ) into a lancing force in an essentially opposing second direction (see arrow D 2  of  FIG. 2 ). It should be noted that D 1  is a direction along the longitudinal axis of firing spring  132  and D 2  is along the longitudinal axis of rod  148 . Firing spring  132  is attached to first end  174  of linkage arm  108 .  
      Priming mechanism  110  of lancing apparatus  100  includes a priming lever  178  (with priming lever proximal end  180  and priming lever distal end  182 ), a priming lever spring  184 , a priming lever pin  186 , a tension member  188 , a priming lever pivot  190 , and an indent  192 .  
      Operation of lancing apparatus  100 , as well as the function of inner housing  102 , firing mechanism  104 , lancing mechanism  106 , linkage arm  108 , and priming mechanism  110  are explained in detail below, not only with respect to  FIGS. 1, 2  and  3 , but also with respect to  FIGS. 7, 8 ,  9  and  10 .  
       FIG. 2  depicts a connector  200  engaged with lancing apparatus  100  and an integrated medical device  300  engaged with connector  200 . Connector  200  and integrated medical device  300  are described below with reference to  FIG. 4  (a simplified side view of a connector  200  that can be used with embodiments of lancing apparatuses and analyte monitoring systems according the present invention),  FIG. 5  (a simplified side view of the connector of  FIG. 4  gripping an integrated medical device  300 ) and  FIG. 6  (a simplified perspective, cut-away view of the connector and integrated medical device of  FIG. 5 ).  
      Referring to  FIGS. 4, 5  and  6 , connector  200  includes an upper strip engaging arm  202  and a lower strip engaging arm  204  (with gap  205  therebetween), a connector arm  206 , a slot  208 , strip engaging elements  210 , and electrical lead connections  212 . Furthermore, connector  200  has a connector distal end  214  and a connector proximal end  216 . Strip engaging elements  210  are in electrical communication with electrical lead connections  212  via a plurality of electrical leads (not shown).  
      Connector  200  is configured to removably retain (i.e., engage with) an integrated medical device  300  within gap  205  between upper and lower strip engaging arms  204  and  202 . Integrated medical device  300  is engaged by strip engaging elements  210 , as depicted in  FIG. 4 .  
      Furthermore, when connector  200  is operatively engaged with lancing apparatus  100 , connector  200  is spring-loaded against depth adjustor spring  162  (see  FIG. 2 ). However, connector  200  can move vertically (in the orientation of  FIG. 2 ) within inner housing  102  when subjected to a lancing force from linkage arm  108 . In other words, connector  200  is slideably retained within lancing apparatus  100  while being spring-loaded against depth adjustor spring  162 . Connector arm  206  of connector  200  protrudes from connector distal end  214  and engages inner surface protrusion  118  of guide rail  120 .  
      Integrated medical device  300  includes a test strip  302  (with test strip reaction area  304 ), a dermal tissue penetration member  306  (with lancet  308 ) and electrical contacts  310 . Integrated medical device  300  can be operatively connected to lancing apparatus  100  by connector  200  (see, for example,  FIGS. 2 and 5 ). Lancet  308  is configured to lance dermal tissue of a target site and draw blood into test strip reaction area  304 . One skilled in the art will recognize that any suitable integrated medical device can be employed including those described in International Application No. PCT/GB01/0 5634 (published as WO 02/49507 on Jun. 27, 2002) and U.S. Patent Application Publication No. 2003/0143113A2, both of which are fully incorporated herein by reference.  
      Strip engaging elements  210  and electrical lead connections  212  of connector  200  are configured to provide electrical communication between integrated medical device  300  and an analyte monitoring system (e.g., analyte monitoring system  400  described below). In this regard, strip engaging elements  210  contact test strip  302  of integrated medical device  300  through electrical contacts  310 . A further description of connector  200 , is included in U.S. Patent Application Publication No. 2005/061700A1.  
      Lancing apparatus  100  is described herein as employing connector  200  and integrated medical device  300 . However, one skilled in the art will recognize that any suitable means can be employed to link a lancing element to lancing apparatus  100  and that lancing apparatuses according to embodiments of the present invention are not limited to use with connector  200  and integrated medical device  300 .  
      Referring again to  FIGS. 1, 2  and  3 , linkage arm  108  is configured to rotate about pivot  164 . As is described in detail below, lancing apparatus  100  is configured in such a way that a firing force in a first direction is converted via pivoting movement of linkage arm  108  into a lancing force in an essentially opposing second direction. Although 180 degrees represents perfect opposition with respect to the first and second directions, an opposition in the range of, for example, +/−15 degrees about 180 degrees is sufficient to provide the benefits described herein. This lancing force causes lancet  308  of integrated medical device  300  to be launched into a dermal tissue target site.  
      Priming lever spring  184  connects proximal end  180  of priming lever  178  to an appropriate surface (such as an inner surface of an analyte monitoring system housing (not shown in  FIGS. 1-3 ). Priming lever  178  is adapted to rotate about priming lever pivot  190 . Indent  192  of priming lever  178  is configured to retain catch  168  of linkage arm  108 . Tension member  188  connects distal end  182  of priming lever  178  to an appropriate related assembly (e.g., to a lid of an analyte monitoring system as described below with respect to  FIG. 15 ) at indent  192 .  
      Priming lever spring  184  can be attached to a suitable related assembly (e.g., an external system housing of an analyte monitoring system as described below). Priming lever spring  184  is employed to place priming lever  178  in a position where priming lever  178  does not interfere with firing mechanism  104  subsequent to the priming of firing mechanism  104 .  
      Once apprised of the present disclosure, one skilled in the art will recognize that priming mechanisms employed in lancing devices according to embodiments of the present invention can take alternative forms to that depicted herein. For example, a suitable priming mechanism can employ a spring-loaded plunger to cooperatively interact with catch  168  rather than the particular lever-based priming mechanism of  FIG. 1 .  
      When depressed during use of lancing apparatus  100 , trigger button  134  initiates launching of lancet  308  into a target site. Stop  156  is engaged with connector  200  and includes a hole (not shown) through which second end  152  of rod  148  passes. First end  150  of rod  148  is engaged with holder  140  such that rod  148  can slide therethrough. Rod  148  passes through retraction spring  142  and is attached to first outer surface  112  via holder  140 .  
      Second end  146  of retraction spring  142  is retained by spring stop  154  and first end  144  of retraction spring  142  is retained by holder  140 . Opening  123  of lancing apparatus  100  is configured to provide for insertion and removal of integrated medical device  300 .  
      Depth adjuster engaging feature  172  of linkage arm  108  is in contact with stepped surface  158  of lancing depth adjuster  138  and serves for a user to set a target site penetration depth of lancet  308 . Lancing depth adjuster  138  can be formed of relatively rigid material including, but not limited to, polystyrene, polycarbonate and polyester or any combination thereof.  
      Trigger spring  136  extends from trigger button  134  to guide rail  120 . Linkage arm pin  170  resides within a slot  208  of connector  200  (see, for example,  FIG. 2 ). Casing  124  serves to retain firing spring  132 . Moreover, firing spring  132  rests on priming lever pin  186  and resides within casing cavity  130  of casing proximal end  128 . Since firing spring  132  is disposed essentially parallel to, and beside, connector  200 , lancing apparatus  100  is relatively compact in length.  
       FIGS. 7, 8 ,  9  and  10  are simplified perspective cut-away views of lancing apparatus  100  in use, with arrows A, A′ and A″ indicating movement of a linkage arm of the lancing apparatus.  
      During use, lancing apparatus  100  is primed by causing priming lever  178  to pivotally rotate about priming lever pivot  190  (see  FIG. 1 ) such that tension is created within tension member  188 . As shown in  FIG. 7 , following priming, linkage arm  108  has been rotated counterclockwise (see arrow A of  FIG. 7 ) about its pivot  164  and has compressed firing spring  132  to a force in the range of, for example, from about 3 Newtons to about 8 Newtons. In addition, retraction spring stop  154  has contacted stop  156  and retraction spring  142  is fully extended between retraction spring stop  154  and holder  140 .  
      Upon depression of trigger button  134  by a user, arm  206  of connector  200  is displaced away from inner surface protrusion  118 . Such displacement of connector arm  206  releases linkage arm  108  to move under the bias of firing spring  132 . Firing spring  132  extends and pushes linkage arm  108  clockwise about its pivot  164  (see arrow A′ of  FIG. 8 ). As firing spring  132  extends, linkage arm  108  engages slot  208  on connector  200  by means of linkage arm pin  170 .  
      As firing spring  132  continues to extend and exert a firing force on linkage arm  108  (in first direction Dl), lancet  308  is extended from lancing apparatus  100  to penetrate a target site (see  FIG. 9 ). This is accomplished as firing spring  132  fully extends causing linkage arm  108  to continue rotating clockwise about pivot  164  (see arrow A″ of  FIG. 9 ) such that extension  166  of linkage arm  108  contacts second end  152  of rod  148 . This contact and associated momentum impart a lancing force (in second direction D 2 ) that compels rod  148  to move toward opening  123  of lancing apparatus  100 , even though there is only a relatively low force (for example, less than about 1.5 N) being exerted by extended firing spring  132 .  
       FIG. 9  also depicts the manner in which retraction spring stop  154  has moved away from stop  156  and towards opening  123  of lancing apparatus  100 . Movement of rod  148  further compresses retraction spring  142  (which is already compressed to a force, e.g., a force in the range of 2 Newtons to 2.5 Newtons). Although retraction spring  142  may be compressed to a force that is greater than that of the now extended firing spring  132 , momentum provides for linkage arm  108  to rotate until it is stopped by contact with stepped surface  158  of lancing depth adjuster  138 . This contact prevents further movement of linkage arm  108 .  
      It should be noted that lancing depth adjuster  138  serves to adjust penetration depth by limiting the movement of linkage arm  108 . The stepped nature of stepped surface  158  enables a user to determine penetration depth by selecting from a plurality of stepped surface portions (see  FIG. 3 ), each of which is designed to prevent the movement of linkage arm  108  at different rotational points.  
      The prevention of further linkage arm movement results in the mass associated with connector  200  also stopping, thereby creating an upward impulse. However, the mass of firing spring  132  and the rotation of linkage arm  108  are stopped simultaneously, creating a downward impulse. The upward and downward impulses tend to beneficially balance each other due to the essentially opposing directions of the firing and launching forces.  
      Since the upward and downward impulses are offset about pivot  164  of linkage arm  108 , a rotational impulse is created. However, since connector  200  is guided by guide rail  120 , the rotational impulse is not transmitted to the target site but rather is transferred to the inner housing and subsequently to the significant mass of the user&#39;s hand. The net effect is that the rotational impulse is not obtrusive and relatively disconcerting to a user.  
      Subsequent to lancing of the target site, the force (e.g., 2 Newtons to 2.5 Newtons) of retraction spring  142  forces serves to force rod  148  to move toward lancing depth adjuster  138  of lancing apparatus  100  while remaining in contact with extension  166  of linkage arm  108  (see  FIG. 10 ). In addition, linkage arm  108  retains connection with connector  200 . Rod  148  continues to move in this manner until retraction spring stop  154  contacts stop  156 . Linkage arm  108  and connector  200  are thus moved by rod  148  while simultaneously retracting lancet  308  from within the target site to a position, for example, at or slightly below the surface of the target site. A small amount of force remaining in firing spring  132  retains the position of linkage arm  108  and maintains the position of lancet  308  at or slightly below the surface of the target site such that lancet  308  may contact bodily fluid within or expressed from the target site.  
       FIG. 11  is a simplified perspective view of an analyte monitoring system  400  according to an exemplary embodiment of the present invention. Analyte monitoring system  400  includes an external system housing  402 , a lancing apparatus (i.e., lancing apparatus  100  of, for example,  FIG. 1 ) integrated with external system housing  402 , and a meter (not shown) for the determination of an analyte in a bodily fluid sample, the meter at least partially contained with the external system housing.  
      Analyte monitoring system  400  also includes a lid  404  that is depicted in an open position (i.e., a first position) in  FIG. 11 . Lid  404  includes a dermal tissue interface  406 , a hinge  408  (not shown in  FIG. 11 , but illustrated in  FIG. 15 ), a lid proximal end  410 , a lid distal end  412  and an outer upper surface  413 .  
      Analyte monitoring system  400  also includes a medical device package storage area  414  (depicted in  FIG. 11  as storing five medical device packages  500 ), a visual display  416 , and display/control buttons  418 . Moreover, external system housing  402  includes a longitudinal side  420 , a first end  422 , a second end  424 , and an inner upper surface  426 . Although, for the purpose of explanation only, five medical device packages are depicted in the storage, any suitable number of medical device packages can be stored.  
      Analyte monitoring systems according to embodiments of the present invention can include any suitable meter including, for example, the electrochemical based meters described in U.S. Pat. Nos. 6,284,125, 6,413,410 and U.S. Patent Application Publication No. 2003/0143113 A2, each of which is hereby incorporated in full by reference.  
       FIG. 12  is a simplified perspective, cut-away view of a medical device package  500  containing an integrated medical device  300  as can be stored in medical device package storage area  414  of analyte monitoring system  400 . Medical device package  500  includes a body  502  with a proximal end  504 , a distal end  506 , a first longitudinal side  508 , a second longitudinal side  510 , an upper surface  512 , a lower surface (not shown in the perspective of  FIG. 12 ), an opening  514 , a cavity  516 , and one or more wings  518 .  
      Medical device package  500  also includes a foil (not shown) covering opening  514 . Opening  514  is located on proximal end  504  and provides access to cavity  516 . Cavity  516  is located within body  502  and is configured to securely and removably retain integrated medical device  300 .  
      Wings  518  provide mechanical reference for insertion of medical device package  500  into lancing apparatus  100 . Wings  518  extend the length of first and second longitudinal sides  508 ,  510  of medical device package  500 . However, one skilled in the art will recognize that such wings can alternatively extend partially along one or both of longitudinal sides  508 ,  510 , be disposed on upper surface  512  or otherwise disposed on body  502 .  
      Although for descriptive purposes, analyte monitoring system  400  is depicted as storing, and otherwise employing, medical device package  500 , any suitable medical device package can be employed with analyte monitoring systems according to embodiments of the present invention. Examples of suitable medical device packages are described in, for example, U.S. Patent Application Publication No. 2005/061700A1.  
       FIG. 13  is a simplified perspective view of analyte monitoring system  400  depicting lid  404  in an open position and a medical device package  500 ′ being employed to insert an integrated medical device into lancing apparatus  100  of the analyte monitoring system.  FIG. 14  is a simplified perspective view representing a portion of  FIG. 13 .  FIG. 15  is a simplified perspective view of the lid and lancing apparatus of the monitoring system of  FIG. 11  depicting the lid in a closed position (i.e., a second position).  FIG. 16  is a simplified perspective view of the analyte monitoring system of  FIG. 11  in use in the hand (H) of a user.  
      Operation of analyte monitoring system  400  is described in detail below with reference to  FIGS. 11 through 16 . When lid  404  of analyte monitoring system  400  is closed (see, for example,  FIG. 15 ), following the insertion of an integrated medical device  300  into lancing apparatus  100  (see  FIG. 14 ), dermal tissue interface  406  on proximal end  410  of lid  404  is disposed directly over opening  123  of lancing apparatus  100 . Therefore, when trigger button  134  is depressed, integrated medical device  300  is launched and lancet  308  penetrates a target site (e.g., a target site on a fingertip of user&#39;s hand H) that has been urged against dermal tissue interface  406  (see  FIG. 16 ).  
      It should be noted that medical device package  500  is removed from opening  123  after integrated medical device  300  has been engaged with connector  200  and before lid  404  is closed.  
      Visual display  416  is located on first longitudinal side  420  and provides a visual interface to direct a user through the use of analyte monitoring system  400 . Display buttons  418  are disposed on longitudinal side  420  near second end  424  and provide for entering commands during use of analyte monitoring system  400 .  
      Lid  404  is disposed above medical device package storage area  414  on outer upper surface  413 . Lid  404  can be formed partly, or wholly, of transparent material such that the contents of medical device package storage area  414  can be viewed therethrough. Hinge  408  is located on distal end  412  of lid  404 .  
      Moving lid  404  from a first position (i.e. open) to a second position (i.e. closed) serves to prime lancing apparatus  100  via the operative connection of tension member  188  to hinge  408  (see  FIG. 15 ). Movement of lid  404  to the first position serves to rotate priming lever  178  about priming lever pivot  190  by exercising a tensile force on tension member  188 , thus cause priming lever  178  to rotate linkage arm  108  counter-clockwise by contacting catch  168  on linkage arm  108 .  
       FIG. 15  depicts windows  115  of lancing apparatus  100 . Openings  115  provide for a calibration code or other information on medical device package  500  to be read therethrough. Although, for the purpose of explanation only, eight windows are depicted in the lancing apparatus, any suitable number of windows can be employed.  
      Referring to  FIG. 16  in particular, trigger button  134  of lancing apparatus  100  extends out of first end  422  of external system housing  402  of analyte monitoring system  400 . A user can grip and operate analyte monitoring system  400  with a single hand (i.e., hand H of  FIG. 16 ) that includes a finger with a target site. The target site is urged against dermal tissue interface  406  and the user&#39;s thumb is employed to depress trigger button  134 . Those skilled in the art will recognize that auto-triggering can be employed as an alternative to manual depression of trigger button  134 , thus eliminating the need for a trigger button. Such auto-triggering could be initiated, for example, by the target site having been urged against dermal tissue interface  406  with a predetermined force.  
      Although  FIGS. 11 and 13 - 16  depict a particular embodiment of an analyte monitoring system according to the present invention, one skilled in the art will recognize that analyte monitoring systems for the determination of an analyte (such as glucose) in a bodily fluid sample (e.g., blood) according to the present invention generally include an external system housing, a lancing apparatus and a meter for determination of the analyte. Moreover, the lancing apparatus is integrated with the external system housing and includes an inner housing, a firing mechanism, a lancing mechanism and a linkage arm. The firing mechanism is configured for producing a firing force in a first direction. The lancing mechanism is configured for delivering a lancing force in a second direction with the second direction being toward a target site and in opposition to the first direction. The linkage arm is pivotably attached to the housing and has first and second ends engaged to the firing and lancing mechanisms, respectively. During use, pivoting of the linkage arm converts the firing force in the first direction into the lancing force in the opposing second direction. Such lancing apparatuses are relatively compact and simple to use, requiring only one hand to operate while obtaining a bodily fluid sample from a target site on the same hand.  
      It should be understood that various alternatives to the embodiments of the invention described herein may be employed in practicing the invention. It is intended that the following claims define the scope of the invention and that structures within the scope of these claims and their equivalents be covered thereby.