Patent Publication Number: US-2011071435-A1

Title: Method and System for Coupling an Extension Wire to a Guidewire

Description:
RELATED APPLICATIONS 
     This application is a Continuation Application of International Application No. PCT/12009/000219 filed on 26 Aug. 2009. This application claims priority from Great Britain application no. 0803656.8 filed Feb. 28, 2008, the entire content of which is hereby incorporated by reference. 
    
    
     FIELD OF THE INVENTION 
     The embodiments of the present invention relate to connection means for coupling an extension wire to a guide wire, and in particular, to a method and to a system wherein a connector is configured as a single-piece unit built to sustain increased separation forces tending to disconnect the extension wire from the guide wire. 
     BACKGROUND OF THE INVENTION 
     Connection means for coupling an extension wire to a guide wire are well known per se. Such connection means usually include a spring coil wound from a single spring wire, operating in association with some kind of tube, as recited in the following patents and patent applications. 
     European Patent Application No. EP 0 799 625 to Lorenzo, recites a coiled spring connecting a guide wire and an extension wire, and a tube disposed over the coiled spring. The tube is attached to slide over the extension wire and to engage the tube. The tube may slide to expand the coil and release the wire. 
     European Patent Application No. EP 0 799 624 to Sasamine et al., recites a guide wire, an extension wire to which a hypotube is permanently affixed, and a spring coil. The hypotube has a tongue to which the spring coil is permanently affixed. The spring coil is configured to receive the extension wire in frictional fit. 
     U.S. Pat. No. 5,421,348 to Lanard recites a guide wire extension system including a guide wire, an extension guide wire, and a connecting assembly mounted on the extension guide wire. The connecting assembly includes a coiled spring arranged to receive and lock with the initial guide wire and a hypotube received loosely in the hypotube. The coiled spring has one end fixed to the tube and another free end. The tube is rotated to withdraw the coiled spring and disconnect the extension wire from the guide wire. 
     U.S. Pat. No. 5,197,486 to Frassica et al., recites a guide wire extension system with a guide wire, an extension guide wire, and a connecting assembly including a coiled spring, a small diameter tube and a rotatable connection disposed between the guide wire and the tube. 
     U.S. Pat. No. 5,113,872 to Jahrmarkt et al., recites a guide wire extension system with an extension guide wire, a guide wire, a connecting assembly including a coiled spring, and a small diameter tube associated with the coiled spring. 
     Further examples include: U.S. Pat. No. 5,415,178 to His et al., U.S. Pat. No. 5,701,911 to Sasamine et al., U.S. Pat. No. 5,788,653 to Lorenzo, and U.S. Pat. No. 5,117,838 to Palmer, et al., all have in common a coil spring wound from a single spring wire and a tube of some kind. 
     However, a single spring wire is able to sustain but limited forces applied thereon. None of the disclosures of the background art ensures a superior separation force, to prevent the connection means to release grip on the guide wire in response to a pull as low as about one Newton, or 1 N. This means that the application of a relatively low pull-apart force disconnects the guide wire from the extension wire. Increased resistance to superior separation forces is not obtainable with a coil spring wound out of a single spring wire. 
     It would be advantageous to provide an extension wire having a connection means that is not restricted to low separation forces, but is configured to offer a pull-apart separation force exceeding the low retention force of commercially available systems and preferably having a pull-apart separation force much higher than required by International Standards for connection means of larger diameter. 
     In addition, it would be advantageous to provide an extension wire having connection means configured as a naked unsupported wound structure of wires without further implement(s), such as support tubes, for coupling to a guide wire. 
     Moreover, it would be advantageous to provide an extension wire able to be coupled by use of a universal connector to any existing configuration of guide wire proximal termination, or at least to the majority of commercially available guide wires. 
     One problem with existing miniature coil spring connectors wound from a single spring wire is the relatively low pull-apart force at which the connection fails, thereby causing release and separation to occur between the guide wire and the extension wire. When a pulling force is exerted on a miniature coil spring, at first, and even under even a relatively low-force pull, the coils expand beyond the elastic limit and suffer a permanent-set plastic deformation. Actually, a low-force pull suffices to first plastically stretch the loops of thin wire from which the helical coil spring connector is made, and second to cause release of grip, whereby the connection fails and the guide wire disconnects from the extension wire. 
     Comparison tests were conducted between a commercially available type of connector and the universal connector of the present claimed invention, details about which are listed in Table 1 hereinbelow. 
     A first set of tensile strength tests was conducted on five samples of a same sturdy commercially available coil spring connector wound from a single 304 stainless steel wire, with the connector coupling a short portion of guide wire to a short portion of extension wire. The single-wire coil connectors had an outer diameter of 0.0134″+/−0.0005″, or about 0.340 mm+/−0.000127 mm, a pitch of 0.1 mm, and a single spring wire of rectangular cross section of 0.1×0.05 mm. The test was performed on a Check Line mechanical test stand made by the Electromatic Equipment Co. Inc. of Cedarhurst, N.Y., USA, model FGS50PUH, operating at the rate of 40 mm/min, until failure by release of the connection. Inches are specified as ″, millimeters are indicated as mm, and a Newton of force is designated as N. 
     Results for a single-wire coiled spring showed that the highest disconnection force reached was 1.992 N, with the lowest release or coupling failure force occurring at 1.049 N. The average failure force was 1.483 N+/−0.4364 N, or roughly, 1.5 N. Forces were measured with a force gage model FG5000A, made by the Lutron Electronic Entreprise Co. Ltd. of Taipei, Taiwan. 
     It turned out that a single spring wire of such small cross-section is too weak to support high pull stresses applied thereon, and thus prohibits the implementation of a reliable helical compression coil spring connector. 
     SUMMARY OF THE INVENTION 
     A solution for enhancing the release force under traction may be provided by use of a helicoidal wire-tube wound from a plurality of metallic spring wires, thus having the general configuration of a helical structure wound from more than one single wire. Such a helicoidal structure may include various configurations all having multiple spring wires. 
     The solution is provided by a universal connector configured as a sleeve having multiple spring wires, or as a hollow stranded wire tube twisted out of a plurality of metallic wires tightly stranded with a high pitch and in gapless contact with each other. Such a universal connector is also referred to hereinbelow as a helical hollow wire-body, or sleeve-body of wires, as best seen in  FIG. 2 . 
     A second set of tensile strength tests was conducted on five sleeve-bodies made from 304 stainless steel wire coupling a short portion of guide wire to a short portion of extension wire. The tested sleeve-bodies of wires, as supplied by the Asahi Intec Co., Ltd. of Nagoya in Japan, had an outer diameter of 0.0136″+/−0.0003″, or about 0.350 mm+/−0.00762 mm, and 12 left-hand wound wires with a pitch of 1.04 mm+/−0.1 mm, and a spring wire diameter of 0.002″ or about 0.05 mm. The second test was performed on the same motorized tensile machine at the same rate of 40 mm/min, until release failure of the connection. 
     Results showed that the highest disconnection force reached for a multi-wire sleeve-body was 13.259 N, with the lowest coupling failure force being 7.031 N. The average failure force was 9.632 N+/−3.114 N, or about 9.6 N. 
     Comparison hence shows that a high-pitched sleeve-body of wires may sustain separation forces superior by about a six-fold over the separation forces that a single-wire coil spring is able to support. 
     
       
         
           
               
               
               
               
               
               
             
               
                 TABLE 1 
               
               
                   
               
               
                   
                 Connector 
                 Wire cross- 
                 Pitch 
                 No. of 
                 Average 
               
               
                   
                 O.D. 
                 section 
                 distance 
                 wires 
                 release 
               
               
                   
                 [mm] 
                 [mm] 
                 [mm] 
                 [#] 
                 [N] 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
            
               
                 Single-wire  
                 0.350 
                 0.1 × 0.05 
                 0.1 
                 1 
                 ~1.5 
               
               
                 304 S.S.  
                   
                   
                   
                   
                   
               
               
                 spring 
                   
                   
                   
                   
                   
               
               
                 Tolerance +/− 
                 0.000127 
                 0.002 
                 0.001 
                   
                   
               
               
                 304 S.S. 
                 0.350 
                 0.050 
                 1.04 
                 12 
                 ~9.6 
               
               
                 multi-wire 
                   
                   
                   
                   
                   
               
               
                 connector 
                   
                   
                   
                   
                   
               
               
                 Tolerance +/− 
                 0.00762 
                 0.00762 
                 0.1 
               
               
                   
               
            
           
         
       
     
     It is an object of the embodiments described hereinbelow to provide a system and a method for releasably coupling an extension wire  200  to a guide wire  300  by use of a universal connector  100 . The guide wire  300  comprises a guide wire exterior diameter GWD, a guide wire body  302  having a guide wire distal portion  304 , and a guide wire proximal portion  306  including a guide wire proximal extremity  308  having reduced dimensions relative to the guide wire exterior diameter and a proximal tip section  310 . The extension wire  200  comprises an extension wire exterior diameter XWD, an extension wire body  202  including an extension wire proximal portion  204  and an extension wire distal portion  206  which terminates in an extension wire distal extremity  208 . 
     The universal connector  100  comprises a connector body  102  of hollow helicoidal structure including a connector length L having a connector exterior diameter UCD, a connector distal portion  104  having a connector distal opening  108  and a connector proximal portion  106  having a connector proximal opening  110 , and a connector lumen  112  extending throughout the length of the universal connector. The connector distal opening  108  is configured for receiving the guide wire proximal extremity  308  into the connector lumen  112  for releasable coupling to the guide wire proximal portion  306 , and the connector proximal portion  106  is fixedly coupled to the extension wire distal portion  206 . 
     The method is characterized by comprising the steps of configuring the universal connector  100  out of a length of a plurality of metallic wires  114  stranded together with a high pitch distance  116  and twisted for tight gapless contact with each other. The connector distal portion  104  is configured as an unconfined cantilevered self-supporting unit wherein the plurality of metallic wires  114  operates in mutual association. Thereby, when the guide wire  300  is coupled to the universal connector  100 , a superior pull-apart resistance force is provided by the plurality of metallic wires against separation forces operating to extract the guide wire  300  out of the universal connector  100 . 
     It is also an object of the embodiments described hereinbelow to provide a universal connector wherein the plurality of metallic wires provide superior pull-apart resistance force relative to the pull-apart resistance force provided by a connector configured to include a single wire helical coil spring. 
     It is another object of the embodiments described hereinbelow to provide a universal connector wherein the high-pitch distance is equal to at least the exterior diameter of the universal connector. Moreover, the high-pitch distance is constant or varies over the length of the universal connector. 
     It is still another object of the embodiments described hereinbelow to provide a universal connector wherein the exterior diameter of the universal connector is selected from a group including of a diameter smaller, equal or larger than the exterior diameter of the guide wire. 
     It is a further object of the embodiments described hereinbelow to provide a universal connector wherein each metallic wire  114  out of the plurality of metallic wires  114  has a wire cross-section shape  118  selected from a group including of circular, square, rectangular, trapezoidal, and oval cross-section shapes. Furthermore, each metallic wire  114  out of the plurality of metallic wires  114  may have a same wire cross-section shape  118  or a different wire cross-section shape and may be made from the same material or from a different material. 
     It is yet another object of the embodiments described hereinbelow to provide a universal connector wherein the proximal connector portion is fixedly coupled to the distal portion of the extension wire. 
     It is another object of the embodiments described hereinbelow to provide a universal connector wherein the proximal connector portion is fixedly coupled to the distal portion of the extension wire. In addition, the universal connector is configured as a hollow helical wire-body sleeve. 
     It is yet another object of the embodiments described hereinbelow to provide a universal connector wherein the connector distal opening  108  and the connector lumen  112  accommodate reception therein of guide wire proximal portions  306  having different proximal tip section  310  configurations, for secure releasable retention. 
     It is still another object of the embodiments described hereinbelow to provide a universal connector wherein a sleeve  122  of flexible film of material covers at least the length of the universal connector for enhancing smooth passage thereover of implements. Preferably, the length L of the connector body  102  is coated with a coat  122  of lubricant for enhancing smooth passage thereover of implements. 
     It is still one more object of the embodiments described hereinbelow to provide a universal connector wherein the flexibility of the universal connector  100  is controlled. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Non-limiting embodiments of the invention will be described with reference to the following description of exemplary embodiments, in conjunction with the figures. The figures are generally not shown to scale and any measurements are only meant to be exemplary and not necessarily limiting. In the figures, identical structures, elements, or parts that appear in more than one figure are preferably labeled with a same or similar number in all the figures in which they appear, in which: 
         FIG. 1  is a schematic illustration depicting a universal connector disposed on an extension wire in the presence of a guide wire, 
         FIG. 2  shows the universal connector in more detail, 
         FIG. 3  depicts details of an extension wire distal portion, the universal connector, and a guide wire proximal portion, 
         FIG. 4  illustrates another embodiment of an extension wire distal portion in direct coupling with a universal connector, and 
         FIG. 5  presents an example of a connector sleeve, or a connector coating. 
     
    
    
     DETAILED DESCRIPTION OF THE DRAWINGS 
       FIG. 1  shows an exemplary embodiment of a universal connector  100 , and  FIG. 2  shows the universal connector only. 
     The universal connector  100  may be described generally as a flexible hollow helicoidal structure, or as a hollow helical wire-body sleeve, which is coupled to an extension wire  200 , appropriately configured for releasably coupling the extension wire  200  to a guide wire  300 . In  FIG. 1 , the guide wire  300  is disposed distally relative to the universal connector  100 , which in turn, is disposed distally relative to the extension wire  200 . 
     Distal or distal direction and proximal or proximal direction are indicated in the FIGS. by arrows marked as, respectively, D and P. 
       FIG. 2  illustrates the universal connector  100 , which is of generally hollow helicoidal structure and may be described as a helical hollow wire-body, or as a wire-stranded hollow tube having a plurality of metallic wires that are wound tightly together. 
     The flexible universal connector  100  may include a connector body  102  having a connector distal portion  104 , a connector proximal portion  106 , a connector length L, and a connector exterior diameter UCD. The connector distal portion  104  has a connector distal opening  108 , and the connector proximal portion  106  has a connector proximal opening  110 . A connector lumen  112  extends throughout the length L of the universal connector  100 , from the connector distal opening  108  to the connector proximal opening  110 . 
     The flexible universal connector  100  may include a plurality of lengths of metallic wires  114  stranded together with a high pitch distance  116  and twisted in pre-stress for tight gapless contact with each other. The connector distal portion  104  is actually configured as an unconfined cantilevered self-supporting unit wherein the plurality of metallic wires  114  operates in mutual association. 
     A pitch distance of the universal connector  100  is considered as the distance from center to center of two adjacent metallic wires. For the universal connector  100 , a high-pitch distance  116  may be regarded as a distance that is at least equal to the exterior diameter UCD of the universal connector  100 . However, the high pitch distance may also be practical with a pitch that is preferably more than one exterior diameter UCD, such as three times, or five times the exterior diameter UCD for example. The high-pitch distance  116  may be constant or may vary over the length L of the universal connector  100 . 
     Each wire  114  out of the plurality of metallic wires  114  has a wire cross-section shape  118 . The shape of the wire cross-section shape  118  may be selected as any desired geometrical shape, preferably out of commercially available wires, but any cross-section shape that may be drawn is feasible. For example, a wire cross-section shape  118  may be selected to be of circular, square, rectangular, trapezoidal, oval, or of other cross-section shape. However, each metallic wire  114  out of the plurality of metallic wires  114  may be selected to have, a same wire cross-section shape  118 , a different wire cross-section shape or a combination of -section shapes. 
     The plurality of metallic wires  114  at the connector distal opening, indicated as a connector free-end  120  in  FIG. 2 , are prevented from unwinding by being coupled together. Such coupling of the strands of the universal connector  100 , or metallic wires  114 , is preferably performed by laser welding, providing a thin layer of welded material to firmly hold the very extremity of the twisted metallic wires at the connector free-end  120  in tight gapless contact with each other. 
     The metallic wires  114  may be selected as wires made of the same material or made of different materials. For example, such materials may include austenitic stainless steels, shape-memory alloys, or super-elastic alloy stainless steel wires, such as a nitinol. Preferably, the metallic wires  114  are disposed as a single layer of wires along the circumference of the universal connector  100 , leaving a central connector lumen  112 , as shown in  FIG. 2 . The number of metallic wires  114  may range from six to 20 for example, preferably 18, and more preferably 12, depending on the universal connector exterior diameter UCD. Moreover, the direction of winding of the plurality of metallic wires  114  may be chosen to be clockwise or anti-clockwise. 
     In  FIG. 1 , the extension wire  200  is depicted to include an extension wire exterior diameter XWD, an extension wire body  202  having an extension wire proximal portion  204  and an extension wire distal portion  206  which terminates in an extension wire distal extremity  208 , to which the universal connector  100  is fixedly coupled. 
     The extension wire proximal portion  204  may be coupled to the extension wire distal portion  206  by any means known in the art, such as for example butt-coupling, stem-coupling, stem-and-support coupling, alone or in any practical combination thereof. Furthermore, secure fixed fastening of the connector  100  to the extension wire  200  may be provided by means known in the art, such as for example welding, brazing, soldering, gluing, or shrink fit. 
     Still in  FIG. 1 , the guide wire  300  is shown to include a guide wire exterior diameter GWD, a guide wire body  302  having a guide wire distal portion  304  and a guide wire proximal portion  306 , which terminates in a guide wire proximal extremity  308  having reduced dimensions relative to the guide wire exterior diameter, and terminating in a guide wire proximal tip section  310 . This means that the guide wire proximal extremity  308  has a reduced exterior diameter relative to the guide wire body  302 , which exterior diameter diminishes gradually towards the proximal tip section  310 . 
     Once the guide wire  300  is coupled to the universal connector  100 , the multi-wire high-pitch helicoidal configuration of the universal connector will provide a superior pull-apart resistance force against separation forces operating to extract the guide wire  300  out of the universal connector  100 . In other words, the plurality of metallic wires  114  provide superior pull-apart resistance force relative to the pull-apart resistance force provided by a background art connection means configured to include a helical spring coil wound with a single spring wire. 
     As already described hereinabove, the extension wire proximal portion  204  may be coupled to the extension wire distal portion  206  by any means known in the art, such as for example butt-coupling, stem-coupling, stem-and-support coupling respectively, or by any practical combination thereof.  FIG. 3  depicts an example of a possible coupling embodiment to fixedly secure the flexible universal connector  100  to the extension wire  200 . 
     In  FIG. 3 , the extension wire distal end portion may be provided with a solid or with a hollow extension wire distal appendage  210 , or with a hollow tube ending distally in a coaxial extension wire distal support  212 . The extension wire distal support  212  is inserted into the connector proximal opening  110  in fit with the connector lumen  112 , and forms a shoulder with the extension wire distal appendage onto which the connector proximal portion  106  abuts, to enhance coupling of the universal connector  100  to the extension wire  200 . The extension wire distal support  212  may be cylindrical or have any other desired shape suitable to facilitate any process, such as manufacture, assembly, and use. 
     The extension wire distal support  212  is preferably an integral portion of the extension wire distal appendage  210 , or is a separate portion attached thereto to provide a support for the universal connector  100 . Alternatively, the extension wire distal appendage  210  is either a separate portion fixedly coupled to the extension wire  200 , or an integral portion of the extension wire  200 . 
     When supported by an appropriately configured extension wire distal support  212 , or when coupled in butt-retention to the extension wire distal extremity  208 , the universal connector  100  may have a universal connector exterior diameter UCD that is smaller, equal, or larger than the guide wire exterior diameter GWD or the extension wire exterior diameter XWD. This means that the universal connector  100 , the extension wire  200 , and the guide wire  300  may all have the same exterior diameter. 
     If desired, the extension wire distal appendage  210  and/or the extension wire distal support  212  may have an extension wire lumen  214  or an extension wire distal support lumen  216 , or both, which disposed in continuation and in communication with a lumen provided and disposed in the interior of the extension wire  200 . Else, the lumen provided in the extension wire  200  may be disposed in direct communication with the connector lumen  112  or the extension wire distal support lumen  216 , or both. Furthermore, the guide wire  300  may have a guide wire lumen  312  pierced throughout and extending out of guide wire proximal tip section  310  to establish communication in continuation with a lumen provided and disposed in the interior of the guide wire  300 . This means that when the guide wire  300  has a guide wire lumen  312  extending distally away from a tip opening of the guide wire proximal tip section  310 , and the extension wire  200  has an extension wire lumen  214 , or an extension wire distal support lumen  216 , or both, extending distally up to and through the guide wire distal portion  304 , then the connector lumen  112  provides a conduit for bi-directional continuous unimpeded passage from the extension wire lumen to the guide wire lumen, and vice versa. In other words, bi-directional communication may be established between the extension wire  200  and the guide wire  300  via the connector  100 . 
     Furthermore, secure fixed fastening of the connector  100  to the extension wire  200  may be provided by means known in the art, such as for example welding, brazing, soldering gluing or shrink fit. 
     The universal connector  100  is universal in the sense that secure and reliable coupling between a guide wire  300  and an extension wire  200  may be achieved irrespectively of the configuration and shape of the guide wire proximal tip section  310  inserted into the connector lumen  112 . For example, the universal connector  100  will accommodate various types of guide wire proximal tip sections  310 , for example screw thread-ended, as shown in  FIG. 3 , or nipple-ended, as depicted in  FIG. 1 . Hence, the connector distal opening  108  and the connector lumen  112  accommodate reception therein of guide wire proximal portions  306  having different proximal tip section  310  configurations, for secure releasable retention. 
     In general, the guide wire proximal end portion may have a guide wire proximal extremity  308  featuring a reduction in exterior diameter relative to the guide wire exterior diameter GWD or to the connector lumen  112 , which terminates in a guide wire proximal tip section  310 . The reduction in exterior diameter may be gradual, decreasing monotonously, for example, from a guide wire nominal exterior diameter GWD of 0.355 mm, or 0.014 inches, down to 0.152 mm, or 0.006 inches. Sometimes, the guide wire proximal tip section  310  is terminated by a screw thread, or ends in any other type of appendage having a reduced diameter relative to the guide wire exterior diameter GWD or to the connecter lumen  112 . 
     The flexibility of the universal connector  100  may be controlled to be stiffer or yielding, thus less rigid, according to desire. Flexibility is dependent on the material of the metallic wires  114 , on the shape of their cross-section  118 , on the pitch distance  116 , on twisting and pre-stressing in tight gapless contact of the metallic wires  114 , or on a mix of all of the above, for example, when the extension wire distal extremity  208  and the guide wire proximal tip section  310  are kept supported and separated apart by a portion of the connector body  102 . Hence, the flexibility of the universal connector  100  may be controlled. 
     However, it is possible to configure the guide wire proximal tip section  310  to be thin enough to penetrate throughout the connector lumen  112 , exit via the connector proximal opening  110 , and penetrate into the extension wire lumen  214 . When the guide wire proximal tip section  310  is seated into the extension wire lumen  214 , it is the rigidity of the guide wire proximal portion  306  that is added to the rigidity of the universal connector  100 , which thereby provides a stiffer universal connector. 
     If desired, only the length L of the universal connector  100 , or also a portion of either one of both or of both the extension wire distal portion  206  and the guide wire proximal portion  306  may be covered with a thin connector sleeve  122  made from synthetic resin for example. 
       FIG. 5  illustrates a connector sleeve  122 , which is shown out of scale in grossly exaggerated dimensions. A connector sleeve  122  may be implemented as a thin and flexible film of material, such as a polymer for example, that covers at least the universal connector for enhancing smooth transition passage of over-the-wire implements over and around the universal connector  100 . It is noted that the length L of the connector body  102  may also be coated with a friction reducing coat of solid lubricant, such as Teflon, which is a registered Trademark, for enhancing smooth transition passage thereover of over-the-wire implements. The connector sleeve  122  may add but a mere 0.0001″, or 0.0254 mm to the universal connector exterior diameter UCD. 
     For operation, thus for releasably coupling of the guide wire  300  to the extension wire  200 , the latter is gripped proximally and held in place relative to the guide wire  300 . It suffices to manually introduce and translate the guide wire proximal portion  306  into the open connector distal opening  108 , until firmly seated and retained therein. 
     In other words, when the guide wire proximal portion  306  is introduced by proximal translation into the universal connector  100 , mutual contact is made in the connector lumen interior  124  with the metallic wires  114 . Then, the guide wire proximal portion  306  is pushed proximally further into the connector lumen  112 , and friction develops between the contacted metallic wires  114  and the contacted guide wire proximal portion  306 . In response to the introduction therein of the guide wire proximal portion  306 , the universal connector  100  may compress, whereby the connector lumen  112  may slightly expand and allow further proximal introduction therein of the guide wire proximal portion  306 , until no further translation is possible. 
     Coupling of the extension wire  200  and of the guide wire  300  may also be carried out manually by mutual and relative translation and rotation. For example, the extension wire  200  may be translated and rotated toward and onto the guide wire  300 , whereby the universal connector  100  will also rotate. Rotation may be carried out in the direction of uncoiling of the metallic wires  114  of the universal connector  100 . Thereby, friction forces develop between the guide wire proximal portion  306  and the interior of the connector lumen  112 , which friction forces will cause the universal connector  100  to slightly expand until translation therein cannot proceed further, to better grip the guide wire proximal portion  306 . 
     At this stage the extension wire  200  is firmly coupled to the guide wire  300 . Disconnection of the guide wire  300  from the universal connector  100  by the mere exertion of separation forces, or pull-apart forces operating to extract the guide wire  300  out of the universal connector, is not possible. This means that a superior pull-apart resistance force is provided by the plurality of metallic wires against separation forces operating to extract the guide wire  300  out of the universal connector  100 . In other words, the plurality of metallic wires  114  provide superior pull-apart resistance force against separation forces relative to the pull-apart resistance force provided connection means having a single-wire helical coil spring. 
     When the guide wire  300  is pulled distally away for extraction out of the universal connector  100 , which is still retained in place proximally, friction forces will urge the universal connector to slightly extend, but firm grip on the guide wire  300  will not be lost. The connector lumen interior  124  may slightly contract to further better grip and augment the forces firmly retaining the guide wire proximal portion  306  into the connector lumen interior. 
     To retrieve the guide wire  200  out of the universal connector  100 , it is necessary to grip the universal connector at the connector distal opening  108 , and then to compress the universal connector  100 . Thereby, the interior of the connector lumen  112  may slightly expand, and allow the guide wire proximal portion  306  to be released and withdrawn in distal translation pull, away from the universal connector  100 . 
     A deliberate manual commanded and controlled action is thus required to disconnect the guide wire proximal portion  306  from the universal connector  100 , in contrast for example, with the recitation of Kontos et al., which requires a mere pull-apart, which pull-apart separation may happen either inadvertently or accidentally. 
     In comparison to background art connection means, as by Table 1 hereinabove, the helicoidal structure configured as a high-pitched sleeve-body of metallic wires  100 , or universal connector  100 , sustains separation forces superior by about a six-fold six over the separation forces that a single wire coil spring is able to sustain. 
     It is also possible to disengage the guide wire  300  from the universal connector  100  in another manner. 
     To disengage the guide wire proximal portion  306  out of the universal connector  100 , it is sufficient to firmly manually hold the guide wire proximal portion in place, while rotating the extension wire  200  relatively thereto, in the direction of uncoiling of the universal connector and simultaneously extracting the universal connector proximally away from the guide wire  300 . 
     When the extension wire distal portion  206  is rotated relative to the guide wire proximal portion  306  in opposite direction to the winding direction of the universal connector  100 , the friction forces tend to unwind the metallic wires  114 , whereby the connector lumen interior  124  may slightly expand, and thereby may allow withdrawal and disconnection by translation. 
     Once again, a deliberate manual commanded and controlled action is required to disconnect the guide wire proximal portion  306  from the universal connector  100 , as opposed to a mere pull-apart traction force, which may happen either inadvertently or accidentally, such as with Kontos et al., for example. 
     In use, a practitioner may intuitively connect and disconnect the universal connector  100  from the guide wire  300  as by the description hereinabove. 
     The connector described hereinabove is thus a universal connector  100 , which may be coupled to any existing guide wire  300  or at least to the majority of the existing guide wires, since the connector distal opening  108  is wide open and has a connector lumen  112  that is configured to receive therein the guide wire proximal portion  306 . This means that at least a proximal portion of the guide wire proximal portion  306  must have external dimensions smaller at least by twice the thickness of the metallic wires  114  relative to the universal connector exterior diameter UCD. In simple words, at least the proximal portion of the guide wire proximal portion  306  must be appropriately dimensioned to penetrate into the connector distal opening  108 . 
     INDUSTRIAL APPLICABILITY 
     The method and the system described hereinabove are appropriate for implementation in industries manufacturing medical instrumentation. 
     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 hereinabove. For example, the functions of the extension wire distal portion  206  and of the guide wire proximal portion  306  may be interchanged, but the operation and use of the universal connector  100  remain the same. This means that the universal connector  100  may be fixedly coupled to the proximal portion  306 , and that the distal portion  206  may be configured for releasable coupling to the universal connector  100 . 
     Rather, the scope of the present invention is defined by the appended claims and includes both combinations and sub combinations of the various features described hereinabove as well as variations and modifications thereof which would occur to persons skilled in the art upon reading the foregoing description. 
     The invention is not limited by the embodiments described above which are presented as examples only but can be modified in various ways within the scope of protection defined by the appended patent claims.