Abstract:
Syringe having a snap-fit mechanism for attaching a needle hub to a syringe barrel in a snap-fit relationship and packaged medical device comprising a syringe with a snap-fit mechanism and a needle hub are provided. An exemplary syringe includes a barrel with a collar and a rotatable arm which allows connection of a needle hub to the barrel in a snap-fit relationship. Additional features of the collar and rotatable arm may also permit disconnection of the needle hub from the barrel without the use of relative rotation of the needle hub and barrel. In a specific configuration, the syringe utilizes a torsional snap-fit element to connect the needle hub to the barrel in a snap-fit rotation. In a more specific configuration, the syringe utilizes a collar with differing interior surfaces which permit snap-fit assembly and disassembly of the needle and the barrel.

Description:
TECHNICAL FIELD 
     Aspects of the present invention relate to syringes having luer snap mechanism for connection to a needle hub in a snap-fit relationship, syringes with a mechanism for attachment of a needle hub to a syringe barrel in a snap-fit relationship without the use of rotational forces and detachment of the needle hub, and packaged medical devices comprising a needle hub and a syringe for connecting to a needle hub in a snap-fit relationship. 
     BACKGROUND 
     Syringes and other medical devices having a luer fitting or connection are often assembled with needle hubs or luer fittings. Two common mechanisms used to connect the needle hubs to the syringes include the “luer lock” and “luer slip” mechanisms. 
     The luer lock mechanism generally includes a male conical fitting in co-axial relation with an internally threaded collar. A cooperating needle hubs or female luer lock fittings have external lugs for engaging the internally threaded collar of the male conical fitting, upon application of a twisting force or torque force to the needle hub. To complete attachment of the needle hub to the syringe, the twisting force must be continued until the external lugs can no longer be threaded into the internally treaded collar of the male conical fitting. To detach the needle hub from the syringe, a twisting force in the opposite direction must be applied to the needle hub. It has been observed that the male conical tip can break off during application of this twisting force and is lodged in the needle hub, rendering both the needle hub and syringe useless. 
     The luer slip fitting includes a male conical fitting in coaxial without a collar. Cooperating needle hubs or female luer slip fittings have an internal surface which slides over the external surface of the male conical fitting. The needle hub is attached to the male conical fitting in a friction fit relationship. To attach of the needle hub to the male conical fitting, the user must apply enough force with sliding the needle hub to create a fluid tight relationship between the needle hub and male conical fitting. Failure to securely connect the needle hub and medical device can result in “pop offs,” where the unsecured needle hub detaches from the male conical fitting during use. 
     A syringe with a connection mechanism for connecting a needle hub to the syringe in a “snap-fit” relationship, as defined herein, presents a viable solution to these issues. It would be desirable to provide an alternate mechanism for connecting the needle hub to a syringe or medical device which provides ease of connection with sensory and/or tactile feedback. Further, specific mechanisms which also provide ease of disconnection would also be desirable. 
     SUMMARY 
     In this disclosure, a convention is followed wherein the distal end of the device is the end closest to a patient and the proximal end of the device is the end away from the patient and closest to a practitioner. 
     A luer snap system for use with a needle hub is provided. The luer snap system may be used to connect a needle hub to a syringe or other medical device. Aspects of this invention, which will be described herein, pertain to syringes having a barrel with a sidewall and inside surface that defines a chamber for retaining fluids. The barrel also has an open proximal end and a distal end, with a distal wall. The distal wall of the barrel includes a luer tip with an opening therethrough in fluid communication with the chamber. Reference to the term “luer tip” shall include a fluid tip which is shaped or otherwise dimensioned to an appropriate standard, such as standards specified by the International Standards Organization (“ISO”), for example, luer tip may include a frusto-conically shaped fluid tip. The term “luer tip,” as used herein, also includes fluid tips configured to a non-ISO standard dimension. 
     The syringe also includes an elongate plunger rod with a proximal end and a distal end that is distally and proximally movable within the chamber of the barrel. The plunger or plunger rod includes a proximal end and a distal end and a main body extending from the proximal end to the distal end. The distal end of the plunger may include a separate or integral stopper with a face or wall which forms a fluid-tight engagement with the inside surface of the barrel. 
     One aspect of the present invention pertains to a syringe comprising a barrel with a mechanism for attaching a needle hub to a barrel in a snap-fit relationship without relative rotation between the needle hub and the barrel. 
     Reference to the term “snap-fit” shall include a mechanical joint system or configuration where two distinct parts are connected or attached with latching features. The mechanical joint system may include one or more flexible latching features which move aside for engagement with a mating part, followed by return of the latching feature toward its original position. The movement of the latching feature to its original position creates an interference to latch the two parts together. The locking feature may be rigid and may force the corresponding part to flex or rotate for attachment. Snap-fit may also include parts which can be assembled and disassembled without any impact on the individual parts and, therefore, can be repeatedly assembled and disassembled. The snap-fit may optionally also include a permanent snap which prevents disassembly. Examples of snap-fit systems or fittings include torsional snap-fit elements, annular snap-fits and cantilever snap-fits. 
     As used herein, the term “torsional snap-fit” includes joints or elements in which deflection is due to torsional deformation of the fulcrum and not the result of flexural loads. Torsional snap-fit also refers to a latch that is attached to one end of an arm portion or lever, which rotates around a fulcrum or a torsion bar. In use, a force applied to the end of the arm portion opposite the latch. The force produces rotation of the arm portion and the latch about the fulcrum and allows a protrusion on a mating part or male joint to proceed past the latch. When the force applied to the arm portion is removed, the arm portion and latch return to their initial position, joining the parts or joints. In some examples, the fulcrum is disposed between the latch and the end of the arm portion. Reference to “annular snap-fits” includes joints featuring a male component with a peripheral ridge or other protrusion and a corresponding female component having an undercut grove formed into the inside diameter of the female component. The male component deflects the female component and engages into the undercut grove, at which point the female component returns to a stress-free condition. Reference to “cantilever snap-fits” includes a hook disposed on the end of a cantilever beam which deflects as it is inserted into a corresponding female component. As the hook passes the edge of the female component, the cantilever beam returns to its original shape. 
     According to one or more embodiments of this first aspect of the invention, the distal end of the barrel includes a mechanism for connecting a female luer fitting, standard luer fitting or a needle hub to the distal end of the barrel. The barrel includes a collar extending from the distal wall and surrounding the luer tip in a coaxial relationship. The collar and luer tip define a channel for receiving a needle hub. The collar also may include a rotatable arm that extends from the collar. In one variant, the rotatable arm may extend inwardly toward the luer tip. The rotatable arm can secure the needle hub to the barrel in a snap-fit relationship by engaging a portion of the needle hub. 
     The rotatable arm can include a pivot portion disposed on the collar that connecting the rotatable arm to the collar. The rotatable arm can also include an arm portion extending radially outwardly from the pivot portion and a latch for securing the needle hub extending into the channel formed between the collar and the luer tip. The rotatable arm can be configured to permit assembly of the needle hub and collar in a snap-fit relationship without relative rotation between the needle hub and the barrel. In a specific embodiment, the rotatable arm prevents removal of the needle hub from the barrel after engagement with a portion of the needle hub or assembly of the needle hub and the collar. In one or more embodiments, the rotatable arm permits removal of the needle hub from the barrel after engagement with a portion of the needle hub or engagement of the needle hub and the collar. The rotatable arm and the open proximal end of the needle hub can be configured such that, when engaged, application of radial force on the rotatable arm permits removal of the needle hub from the collar. For example, the radial force to permit removal of the needle hub from the barrel may include an inwardly directed radial force or a radial force directed toward the luer tip on the rotatable arm. In another example, the radial force for removal of the needle hub from the barrel includes an outwardly directed radial force or a radial force directed away from the luer tip. 
     In another embodiment of the present invention, the rotatable arm includes a torsional snap fit element. In such embodiments, the syringe may also include a hub with an open proximal end with an outwardly extending lip positioned to engage the torsional snap-fit element. As the hub advances in the channel formed by the collar and the luer tip, the outwardly extending lip advances past the torsional snap-fit element, thereafter the torsional snap-fit element prevents movement of the outwardly extending lip in the distal direction. The torsional snap-fit element may provide tactile and/or audible indication of the advancement of the outwardly extending lip past the torsional snap-fit element. After engagement between the torsional snap-fit element and the outwardly extending lip, application of an inwardly directed radial force on the torsional snap-fit element permits movement of the outwardly extending lip in the distal direction. 
     A second aspect of the present invention includes a syringe with means for attaching a standard luer fitting to the distal wall of the barrel. In one or more embodiments, the means may attach the standard luer fitting to the distal wall of the barrel in a snap-fit relationship and may also prevents removal of the standard luer fitting or disengagement of the snap-fit relationship between the standard luer fitting and the distal wall. Exemplary means for attaching the standard luer fitting 
     According to one or more embodiments, the means for attaching the standard luer fitting to the barrel includes a co-axial collar that surrounds the luer tip to form a cavity. The cavity is further configured to receive a standard luer fitting. In a specific embodiment, the co-axial collar may include a first interior surface having a rotatable arm and a latch disposed on the rotatable arm extending from the first interior surface into the cavity and a second interior surface that is free of a rotatable arm or latch. In one or more embodiments, the latch is configured to engage a portion of the standard luer fitting, such as a lip disposed on the proximal end of the standard luer fitting. Upon rotation of the standard luer fitting relative to the co-axial collar to align the portion of the standard luer fitting with the second interior surface, the standard luer fitting is permitted movement in the distal direction and the snap-fit relationship between the standard luer fitting and the collar is released. 
     The syringe according to the second aspect may further include a standard luer fitting that includes an open proximal end configured to advance into the cavity. The open proximal end of one or more embodiments may also include an outwardly extending lip. In such embodiments, upon advancement of the open proximal end into the cavity, the lip advances past the latch in the proximal direction. The latch prevents movement of the lip in the distal direction. Upon rotation of the standard luer fitting to align the lip with the second interior surface, the lip of the needle hub is permitted movement in the distal direction. 
     In accordance with the embodiments described herein, the syringe barrel may further include provide audible and/or tactile indication of the snap-fit engagement, connection or relationship between the needle hub and the barrel. 
     A third aspect of the present invention pertains to a packaged medical device comprising a needle hub and a syringe, as described herein, in a single package. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates a disassembled perspective view of a syringe assembly according to an embodiment of the invention; 
         FIG. 2  illustrates a perspective assembled view of the syringe assembly of  FIG. 1 ; 
         FIG. 3  shows a cross-sectional view of the syringe assembly shown in  FIG. 2  taken along line  3 - 3 ; 
         FIG. 4  is an enlarged view of a portion of the barrel shown in  FIG. 3 ; 
         FIG. 5  is an enlarged cross-sectional view of the distal end of the barrel shown in  FIG. 1  taken along line  5 - 5 ; 
         FIG. 6  illustrates a disassembled perspective view of a syringe according to an alternative embodiment of the invention; 
         FIG. 7  illustrates a perspective assembled view of the syringe assembly of  FIG. 6 ; 
         FIG. 8  shows a cross-sectional view of the syringe assembly shown in  FIG. 7  taken along line  8 - 8 ; 
         FIG. 9  is an enlarged view of a portion of the barrel shown in  FIG. 8 ; 
         FIG. 10  is a cross-sectional view of the distal end of the barrel shown in  FIG. 6  taken along line  10 - 10 ; 
         FIG. 11  illustrates a disassembled perspective view of a syringe according to an alternative embodiment of the invention; 
         FIG. 12  illustrates a perspective assembled view of the syringe assembly of  FIG. 11 ; 
         FIG. 13  shows a cross-sectional view of the syringe assembly shown in  FIG. 12  taken along line  13 - 13 ; 
         FIG. 14  is an enlarged view of a portion of the barrel shown in  FIG. 13 ; and 
         FIG. 15  is a cross-sectional view of the distal end of the barrel shown in  FIG. 11  taken along line  15 - 15 . 
     
    
    
     DETAILED DESCRIPTION 
     Before describing several exemplary embodiments of the invention, it is to be understood that the invention is not limited to the details of construction or process steps set forth in the following description. The invention is capable of other embodiments and of being practiced or being carried out in various ways. 
     One aspect of the present invention provides for a syringe including a plunger rod and barrel, which has features and construction which allow the user to attach a needle hub or standard luer fitting to the barrel in a snap-fit relationship or connection. 
       FIGS. 1-5  show a syringe or syringe assembly  100  having a barrel  150 , plunger rod  180  and stopper  160 , arranged such that the proximal end of the stopper  169  is attached to the distal end  181  of the plunger rod. The connected stopper  160  and plunger rod  180  are inserted into the proximal end  159  of the barrel  150 . 
     With reference to  FIGS. 2-5 , the barrel  150  has a cylindrical sidewall  153  with an interior surface  154  that defines a chamber  155 . In one embodiment, the chamber  155  holds the contents of the syringe, which may include medication. The barrel  150  includes an open proximal end  159 , a distal end  151  and a distal wall  152 . The distal wall  152  includes a luer tip  134  having a luer tip opening  136  and a collar  130  defining a channel  132  with the luer tip  134 . The collar  130  also includes a rotatable arm  140  and a peripheral gap  138 . As will be more fully described herein, the rotatable arm  140  can engage a portion of the needle hub to permit assembly of a needle hub and collar in a snap-fit relationship. 
     The sidewall  153  of the barrel  150  defines a chamber  155  having a continuous inner diameter along the longitudinal axis of the syringe. Alternatively, the barrel can include a sidewall has an inner diameter, which decreases linearly from the proximal end to the distal end. It is to be understood that the configuration shown is merely exemplary, and the components can be different in shape and size than shown. For example, the barrel can have an exterior prism shape, while retaining a cylindrical interior shape. Alternatively, both the exterior and interior surfaces of the barrel can have non-circular cross-sectional shapes. 
     The syringe barrel  150  is shown as having a peripheral flange  158  attached at the proximal end  159  of the barrel  150 . The syringe shown in  FIG. 1  includes an optional needle hub  120  having an open proximal end  129  and a distal end  121 , which includes a needle cannula  122  having a lumen  123 . When assembled, as shown in  FIG. 2 , fluid communication is established between the chamber  155  of the barrel  150  through the luer tip opening  136  of the luer tip  134 , the needle hub  120  and the lumen  123  of the needle cannula  122 . 
     The plunger rod  180  shown in  FIG. 1  includes proximal end  189 , a distal end  181  and a main body  182  extending between the proximal end  189  to the distal end  191 . The plunger rod  180  further includes a thumb press  188  at the proximal end  189  of the plunger rod  180 . The distal end  181  of the plunger rod may include a stopper engagement portion  183  for attaching the stopper  160  to the distal end  181  of the plunger rod. The stopper  160  shown in  FIG. 1  is a separate component, though it will be understood that the stopper may be integrally formed with the plunger rod in accordance with the embodiments described herein. The stopper  160  includes a distal end  161 , a proximal end and a stopper face  162  and sealing edge  165  at the distal end  161  of the stopper  160 . 
     As more clearly shown in  FIGS. 3 and 4 , when assembled in a snap-fit relationship, the open proximal end  129  of the needle hub moves into the channel  132  and the rotatable arm  140  engages the open proximal end  129  of the needle hub  120 . The rotatable arm  140  shown in  FIGS. 1-5  includes a pivot portion  146 , extending radially outwardly from the collar  130 . The pivot portion  146  provides a fulcrum to allow movement of the rotatable arm  140 . The rotatable arm  140  may include an arm portion  144  that moves or rotates about a pivot portion  146 . As shown in  FIGS. 1-5 , the rotatable arm includes a latch  142  between the pivot portion  146  and the arm portion  144 . Such an arrangement may be referred to as a second-class lever, wherein when a force applied to the arm portion  144 , a resultant force is exerted on the latch  142  or at a location between the arm portion  144  and the pivot portion  146 . The pivot portion  146  permits or facilitates movement of the arm portion  144  and the latch  142  radially inwardly or radially outwardly, in relation to the collar. This movement is user actuated, for example, by a practitioner assembling the syringe of  FIGS. 1-5 . 
     One skilled in the art would recognize that the barrel shown in  FIGS. 1-5  could be used with standard needle hubs or needle hubs which confirm with ISO standards, such as, for example, ISO 594. As shown in  FIGS. 1-5 , during assembly, a portion of the needle hub  124  (see  FIG. 1 ) at the open proximal end  129  of the needle hub enters the channel  132 , moves proximally past the latch  142  of the rotatable arm  140  and into that peripheral gap  138  of the collar  130 . In the embodiment shown, the rotatable arm  140  permits a snap-fit relationship between the needle hub and the barrel, without relative rotation. The rotatable arm  140  may further provide an audible and/or tactile indication of the snap-fit engagement or relationship between the needle hub  120  and collar  143 . For example, the latch  142  may resist movement of the needle hub  120  into the channel  132  and thereby provide tactile indication or feedback of the proximal movement of the needle hub  120  into the channel  132  and engagement with the rotatable arm  140 . The arm portion  146  and latch  142  may alternatively flex as the needle hub  120  travels proximally past the arm portion  144  and latch  142  regain their original position after the needle hub  120  has moved completely into the channel  132 . In such embodiments, as the arm portion  144  and latch  142  regain their original position, it may produce audible indication of the engagement of the latch  142  and the needle hub  120 . 
     To release the portion of the needle hub  124 , a radial force may be applied to the arm portion  144 . As shown in  FIG. 5 , application of an outwardly directed radial force or an application of a radial force in a direction away from the luer tip  134  on the arm portion  144  permits removal of the needle hub  120  from the latch  142  by permitting movement of the portion of the needle hub  124  in the distal direction. It will be understood that, removal of the needle hub  120  from the barrel  150  may also be permitted upon application of an inwardly directed radial force or a radial force in a direction toward the luer tip  134 . 
     Optionally, the arm portion  144  may be dimensioned and spaced from the distal wall  142  to prevent application of a radially outwardly directed force to the arm portion  144  and/or to prevent access to the arm portion  144  by a user. In such embodiments, once the needle hub  120  is engaged to the latch  142  or engaged with the barrel  150  in a snap-fit relationship, removal of the needle hub  120  or disengagement of the latch  142  from the needle hub  120  and reuse of a syringe is not permitted. 
       FIG. 6  shows a second embodiment of a syringe according to the present invention. As with the embodiment shown in  FIG. 1 , the syringe assembly  200  includes a barrel  250 , plunger rod  280  and a separate stopper  260 , arranged such that the proximal end of the stopper  269  is attached to the distal end  281  of the plunger rod. The connected stopper  260  and plunger rod  280  are inserted into the proximal end  259  of the barrel  250 . An optional standard luer fitting  220  may be attached to the distal end  241  of the barrel. 
     As more clearly shown in  FIGS. 7-10 , the barrel  250  includes a sidewall  253  with an inside surface  254  that defines a chamber  255 . The barrel  250  includes an open proximal end  259 , a distal end  251  and a distal wall  252 . The distal wall  252  includes a luer tip  234  with an aperture  236 . The distal wall  252  also includes a sleeve  230  in coaxial relationship with the luer tip  234  and defining a cavity  232  with the luer tip  234 . The sleeve  230  further includes a peripheral opening  238 . The syringe barrel  250  is shown as also having a pair of finger grips  258  attached at the proximal end  259 . 
     The plunger rod  280  shown in  FIG. 6  includes proximal end  289 , a distal end  281  and a main body  282  extending between the proximal end  289  to the distal end  281 . The plunger rod  280  further includes a thumb press  288  at the proximal end  289  of the plunger rod  280 . The distal end  281  of the plunger rod may include a stopper engagement portion  283  for attaching the stopper  260  to the distal end  281  of the plunger rod. The stopper  260  shown in  FIG. 6  includes a distal end  261 , a proximal end and a stopper wall  262  and sealing perimeter  265  at the distal end  261  of the stopper  260 . 
     The syringe may include means for attaching or attachment of a needle hub or standard luer fitting to the barrel in a snap-fit relationship. Examples of suitable means for attaching include a universal connection (not shown), which may also include an optional means for releasing (not shown) the standard luer fitting from the barrel. 
     The means for attaching a needle hub or standard luer fitting to a barrel may also include a rotatable arm. The rotatable arm may include a first class lever having a fulcrum located between the point at which a force is applied and the point at which a resulting force is exerted. For example, a first class lever may include a bar having two opposite ends attached to a fulcrum so that the two ends remain free. Application of a force on one end of the bar causes the bar to swing or rotate about the fulcrum, and a resultant force is exerted by the opposite end of the bar. 
     In  FIGS. 6-10 , the rotatable arm  240  is in the form of a torsional snap-fit element  241 . The torsional snap-fit element  241  includes a latch  242  extending into the peripheral opening  238 , when in a relaxed or stress-free state. As shown in  FIGS. 6-10 , the arm portion is in the form of a torsion bar  244 , which connects to a latch  242 . The torsion bar  244  is also attached to a pivot portion, which is shown in the form of a fulcrum portion  246 . 
     As will be understood by one of ordinary skill in the art, application of a force to the torsion bar  244  causes the torsion bar  244  and latch  242  to rotate around the fulcrum portion  246 . This rotation allows the latch  242  to rotate radially outwardly from the peripheral opening  238  and permits the standard luer fitting to proceed past the latch  242 . When the force applied to the torsion bar  244  is released or removed, the latch  242  and the torsion bar  244  return to their initial positions or to a relaxed or stress-free state. 
     The optional standard luer fitting  220  shown in  FIG. 6  includes an open proximal end  229  and a distal end  221 , which includes a needle cannula  222  having a lumen  223 . The open proximal end  229  of the standard luer fitting includes an extending lip  224 . As more clearly shown in  FIGS. 8 and 9 , when assembled in a snap-fit relationship, the open proximal end  229  of the standard luer fitting moves into the cavity  232 , proximally past the latch  242  of the torsional snap-fit element  240  and into the peripheral opening  238 . As otherwise described herein, application of a radially inwardly directed force on the torsion bar  244  causes the latch  242  and torsion bar  244  to rotate around the fulcrum portion  246  as the extending lip  224  moves past the latch  242 . After movement of the extending lip  224  proximally past the latch  242 , the force applied to the torsion bar  244  is released and the latch  242  and the torsion bar  244  return to their initial position, with the latch  242  positioned proximally adjacent to the extending lip  224 . In accordance with one or more embodiments, this initial rotation and return to an initial position provides tactile indication and/or audible indication of the snap-fit relationship between the standard luer fitting  220  and the barrel  250 . 
     After assembly of the snap-fit relationship, the latch  242  prevents movement of the extending lip  224  of the standard luer fitting in the distal direction. The rotatable arm may be configured to permit removal of the standard luer fitting  220  after establishment of the snap-fit relationship. To release the standard luer fitting  220  from the snap-fit relationship with the barrel  250 , a force is be applied on the arm portion  244  to cause the latch  242  and torsion bar  244  to rotate around the fulcrum  246  and permit the extending lip  224  to move distally past the latch  242 . Alternatively, the rotatable arm may be configured to remain in a locked position and prevent removal of the standard luer fitting  220  from the barrel. 
     An additional embodiment of a means for attaching the standard luer fitting and barrel is shown in  FIGS. 11-15 . In this embodiment, the means includes a rotatable arm with an arm portion in the form of a tab  344  attached at one end to a pivot portion in the form of a connection point  346 . The tab  344  further includes a latch  342  at the end opposite the connection point  346 . 
       FIG. 11  shows a syringe assembly  300  having a barrel  350 , plunger rod  380  and a stopper  360 , arranged such that the proximal end of the stopper  369  is attached to the distal end  381  of the plunger rod. The connected stopper  360  and plunger rod  380  are inserted into the proximal end  359  of the barrel  350 . 
     The barrel  350  has a cylindrical sidewall  353  with an inside surface  354  that defines chamber  355 . The barrel  350  includes an open proximal end  359 , a distal end  351  and a distal wall  352 . The distal wall  352  includes a luer tip  334  with an opening  346 . The distal wall  352  also includes a coaxial collar  330  surrounding the luer tip  334  and defining a peripheral recess  332 . The syringe barrel  350  includes optional flanges  258  attached at the proximal end  359 . 
     The plunger rod  380  shown in  FIG. 11  includes proximal end  389 , a distal end  381  and a main body  382  extending between the proximal end  389  to the distal end  391 . The plunger rod  380  further includes a thumb press  388  at the proximal end  389  of the plunger rod  380 . The distal end  381  of the plunger rod may include a stopper engagement portion  383  for attaching the stopper  360  to the distal end  381  of the plunger rod. The stopper  360  shown in  FIG. 11  includes a distal end  361 , a proximal end and a stopper wall  362  and seal  365  at the distal end  361  of the stopper  360 . 
     As more clearly shown in  FIGS. 12-15 , the optional means for attaching the standard luer fitting and barrel includes coaxial collar  330  having distal end  331  and a proximal end  339  having a open slot  338  disposed between the distal end  331  and the proximal end  339 . The coaxial collar  330  further includes a first interior surface and a second interior surface. A rotatable arm  340  projects from the first interior surface of the coaxial collar  330  into peripheral recess  332  and open slot  338 . The second interior surface includes no projection or impediment extending into the channel. As shown in  FIGS. 11-15 , the arm portion of the rotatable arm  340  includes a radially inwardly projecting or extending tab  344 . The tab  344  is connected to the coaxial collar  330  at a pivot portion, which includes a connection point  346 . The tab  340  is rotatable or deflectable at the connection point  346  and includes latch feature  342  at its proximal end. As shown, the tab  344  is not user actuated and cannot be used to disengage the needle hub from the barrel. 
     For assembly, the needle hub  320  enters the peripheral recess  332  such that the extending lip  324  is aligned with the first interior surface or with the tab  340 . As the needle hub  320  moves into the peripheral recess  332 , the extending lip  324 , the tab  340  is deflected at the connection point  344  and the needle hub  320  is permitted to move fully into the peripheral recess  332  and extend radially outwardly through the open slot  338 . Where a third class lever is utilized for the rotatable arm  340 , the movement of the extending lip  324  into the peripheral recess  332  exerts a force on the tab  344  between the latch  342  and the connection point  346 . The resulting force deflects the tab  344  and the latch  342 , permitting the extending lip  324  to advance proximally past the latch  342 . This movement of the extending lip  324  proximally past the tab  344  provides tactile and audible indication to the user. While aligned with the first interior surface, the latch  342  prevents movement of the extending lip  324  in the distal direction. 
     To remove the needle hub  320 , the standard luer fitting  320  is rotated relative to the coaxial collar  330  and to align the extending lip  324  with the second interior surface, which is free of any impediment to movement of the extending lip  324  in the distal direction. Such alignment would permit removal of the needle hub  320  from the barrel. As shown in  FIGS. 11-15 , rotation of the needle hub relative to the barrel or coaxial collar is up to 90 degrees. Alternatively, the rotation of the needle hub relative to the barrel may be up to 180 degrees. The needle hub  230  may then be removed from the peripheral recess  332 . 
     The syringe of  FIGS. 11-15  may be structured to also prevent reuse thereof after the needle hub has been attached to the barrel in a snap-fit relationship. For example, upon assembly of the needle hub  320  to the barrel, extension of the extending lip  324  through the open slot  338  of the coaxial collar  330  prevents rotation of the needle  320  relative to the coaxial collar  330  and, thereby prevents removal thereof. The rotatable arm  340  may also be dimensioned and/or positioned to prevent user actuation and, once the needle hub is attached in a snap-fit relationship with the barrel, to prevent disengagement thereof. 
     Reference throughout this specification to “one embodiment,” “certain embodiments,” “one or more embodiments” or “an embodiment” means that a particular feature, structure, material, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. Thus, the appearances of the phrases such as “in one or more embodiments,” “in certain embodiments,” “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily referring to the same embodiment of the invention. Furthermore, the particular features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments. 
     Although the invention herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It will be apparent to those skilled in the art that various modifications and variations can be made to the method and apparatus of the present invention without departing from the spirit and scope of the invention. Thus, it is intended that the present invention include modifications and variations that are within the scope of the appended claims and their equivalents.