Abstract:
Systems, devices, and methods are provided for a catheter device for use in a medical procedure wherein the interior of the catheter device expands to accommodate longitudinal expansion of the expandable member to compress cancellous bone.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority to and the benefit of U.S. Provisional Patent Application Ser. No. 62/074,781 filed Nov. 4, 2014, which is incorporated by reference herein in its entirety for all purposes. 
     
    
     FIELD 
       [0002]    The subject matter described herein relates generally to catheter devices used in medical procedures. 
       BACKGROUND 
       [0003]    Osseous tissue or bone tissue generally makes up the skeletal system of vertebrates. In humans, osseous tissue is made of cancellous bone and cortical bone. Cortical bone is generally solid and strong and provides a shell for cancellous bone which is also known as trabecular or spongy bone. In some humans cancellous bone may become diseased and lose mass and density, thus increasing risk of fractures or breaks in the bone. This decrease in bone mass and density is commonly referred to as osteoporosis and frequently affects the elderly. Medical procedures have been developed to treat osteoporosis and provide additional support to bones. 
         [0004]    Some procedures require drilling through the cortical bone to treat the cancellous bone inside. Once a hole has been drilled in the cortical bone a catheter may be used to treat the cancellous bone. In some procedures a catheter with an expansion member, such as a balloon, near the end is introduced into the cancellous bone and the expansion member is expanded in order to compact the cancellous bone. After compacting the cancellous bone, a void in the cancellous bone is sometimes created and this void may be filled with bone cement to provide added strength for the bone. 
         [0005]    Removal of a catheter with a balloon near its end can be complicated. Typically the balloon is deflated before removal from the hole in the cortical bone but problems may occur if, for example, the balloon is bulky in its deflated state or the balloon does not fully deflate before its attempted removal. A typical balloon inflates circumferentially as well as longitudinally from a deflated state closely wrapped to the underlying catheter body. In the case of longitudinal expansion the balloon may inflate beyond the distal tip of the catheter device. This can be problematic when extraction is attempted if the deflated balloon remains beyond the distal tip of the catheter device as the structure may be too bulky to pass through the cortical hole or to retract inside a cannula. As such, the development of devices with improved physical characteristics during medical procedures and ease of extraction following the medical procedures is advantageous. 
       SUMMARY 
       [0006]    Provided herein are catheter devices for use in medical procedures and methods of using and manufacturing the devices. The devices are designed to provide ease of extraction after completion of the intended procedure. Systems and kits containing these devices are also provided herein. Although not limited to such, these devices, systems, and methods are described in the context of procedures for compacting cancellous bone. The catheter devices described herein preferably include multiple catheter tubes with a limited separable structure within an expandable member which may be delivered by a cannula. The configuration of these devices is described in detail by way of various embodiments which are only examples. 
         [0007]    Other systems, devices, methods, features and advantages of the subject matter described herein will be or will become apparent to one with skill in the art upon examination of the following figures and detailed description. It is intended that all such additional systems, devices, methods, features and advantages be included within this description, be within the scope of the subject matter described herein, and be protected by the accompanying claims. In no way should the features of the example embodiments be construed as limiting the appended claims, absent express recitation of those features in the claims. 
     
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         [0008]    The details of the subject matter set forth herein, both as to its structure and operation, may be apparent by study of the accompanying figures, in which like reference numerals refer to like parts. The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the subject matter. Moreover, all illustrations are intended to convey concepts, where relative sizes, shapes and other detailed attributes may be illustrated schematically rather than literally or precisely. 
           [0009]      FIG. 1  is a perspective view depicting an example embodiment of the catheter device without an expandable member. 
           [0010]      FIG. 2  is a partial cross-sectional side view depicting an example embodiment of the catheter device without the expandable member. 
           [0011]      FIG. 3  is a partial cross-sectional top view depicting an example embodiment of the catheter device without the expandable member. 
           [0012]      FIG. 4  is enlarged partial cross-sectional side view depicting an example embodiment of the catheter device with the expandable member in an inflated configuration. 
           [0013]      FIG. 5  is a side view depicting an example embodiment of the full catheter device. 
           [0014]      FIG. 6  is a perspective view of the full catheter device. 
           [0015]      FIG. 7  is a cross section depicting an example embodiment of the catheter device with an expandable member in an uninflated configuration. 
           [0016]      FIG. 8  is a side view depicting an example embodiment of the catheter device with a shim spacer. 
           [0017]      FIG. 9  is a side view depicting an example embodiment of the catheter device with a shim spacer and the expandable member in an inflated configuration. 
           [0018]      FIG. 10  is a flow diagram depicting an example embodiment of a manufacturing process. 
           [0019]      FIGS. 11A-11B  are diagrams depicting an example embodiment of manufacturing steps for an interior of the device. 
           [0020]      FIGS. 12A-12C  are diagrams depicting an example embodiment of subsequent manufacturing steps for the interior of the device including creation of a first side of an inflation port for the interior of an expandable member. 
           [0021]      FIGS. 13A-13B  are diagrams depicting an example embodiment of additional manufacturing steps for the interior of the device including trimming a portion of a proximal tube. 
           [0022]      FIG. 14  is a side view depicting an example embodiment of tubing for use in the construction of a catheter. 
           [0023]      FIGS. 15A-B  are diagrams depicting an example embodiment of additional manufacturing steps for an interior of the device including bonding a proximal and distal tube to create a third tube with an inflation port. 
           [0024]      FIGS. 16-21  are side views depicting additional example embodiments of the catheter device during various manufacturing steps. 
           [0025]      FIGS. 22A-B  are side and perspective views, respectively, depicting a normal spinal column. 
           [0026]      FIGS. 23A-B  are side and perspective views, respectively, depicting a spinal column with a fracture in one vertebrae. 
           [0027]      FIGS. 24-25  are partial cross-sectional views depicting an example embodiment of the catheter device with the expandable member inflated within a spinal column to compress cancellous bone. 
           [0028]      FIG. 26  is a partial cross-sectional view depicting an example embodiment of the catheter device with bone cement injected into a space within the spinal column after deteriorating cancellous bone has been compressed. 
       
    
    
     DETAILED DESCRIPTION 
       [0029]    Before the present subject matter is described in detail, it is to be understood that this disclosure is not limited to the particular embodiments described, as such may, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting, since the scope of the present disclosure will be limited only by the appended claims. 
         [0030]    As used herein and in the appended claims, the singular forms “a”, “an”, and “the” include plural referents unless the context clearly dictates otherwise. 
         [0031]    The publications discussed herein are provided solely for their disclosure prior to the filing date of the present application. Nothing herein is to be construed as an admission that the present disclosure is not entitled to antedate such publication by virtue of prior disclosure. Further, the dates of publication provided may be different from the actual publication dates which may need to be independently confirmed. 
         [0032]    It should be noted that all features, elements, components, functions, and steps described with respect to any embodiment provided herein are intended to be freely combinable and substitutable with those from any other embodiment. If a certain feature, element, component, function, or step is described with respect to only one embodiment, then it should be understood that that feature, element, component, function, or step can be used with every other embodiment described herein unless explicitly stated otherwise. This paragraph therefore serves as antecedent basis and written support for the introduction of claims, at any time, that combine features, elements, components, functions, and steps from different embodiments, or that substitute features, elements, components, functions, and steps from one embodiment with those of another, even if the following description does not explicitly state, in a particular instance, that such combinations or substitutions are possible. It is explicitly acknowledged that express recitation of every possible combination and substitution is overly burdensome, especially given that the permissibility of each and every such combination and substitution will be readily recognized by those of ordinary skill in the art. 
         [0033]      FIGS. 1-6  are various views depicting an example embodiment of a catheter device  100  for use in compacting cancellous bone. Here, catheter device  100  has a distal end  102  and a proximal end  103 .  FIGS. 1, 2, and 3  are a perspective view, partial cross-sectional side view, and partial cross-sectional top view, respectively, of catheter device  100  in an intermediate stage of construction prior to attachment of an expandable member  150 .  FIG. 4  is a partial cross-sectional side view depicting catheter  100  in a late or final stage of construction after attachment of expandable member  150 .  FIGS. 5-6  are side and perspective views, respectfully, of the entire catheter  100  with a proximal controller  101 , which allows the operation and manipulation of catheter device  100  and includes an inflation inlet and deflation outlet for expandable member  150 . 
         [0034]    Catheter device  100  includes, in part, a first tubular member (or tube)  110  located generally proximally, a second tubular member (or tube)  120  located distal to and separated from first tubular member  110 , and a third tubular member (or tube)  130  within which first tube  110  and second tube  120  are located. 
         [0035]    In this embodiment, first tube  110  has an inner lumen  112  and an open beveled end  113 . Third tube  130  has an opening in its sidewall over open beveled end  113  such that an inflation port  106  is formed through which an inflation medium (e.g., saline) can pass from inner lumen  112  of first tube  110  to inflate expandable member  150 . The opening in beveled end  113  is shown as having an oval shape in  FIG. 3 , although any profile shape can be used. 
         [0036]    A proximal end  114  of first tube  110  extends proximally to (or constitutes) proximal end  103  of catheter  100 . A proximal end  134  of third tube  130  is positioned at an intermediate location along the catheter shaft. An outer sheath  104  can extend along the majority or all of first tube  110  and can cover proximal end  134  of third tube  130  such that the outer sheath&#39;s distal end  105  is between third tube proximal end  134  and inflation port  106 . In alternative embodiments, third tube proximal end  134  can extend to proximal end  103  of catheter  100  with first tube  110 , or instead of first tube  110  if proximal end  114  terminates at an intermediate location. 
         [0037]    The terminus of distal end  113  of first tube  110  is separated from the terminus of a proximal end  124  of second tube  120  such that, of the three tubes  110 ,  120 , and  130 , only third tube  130  extends therebetween. As will be described later, e.g., with respect to  FIGS. 11-15 , in some embodiments, third tube  130  is formed by bonding a proximal tube with a distal tube to form a single continuous tube. In other embodiments, third tube  130  is formed from a single continuous member without coupling multiple tubes together. Third tube  130  can be formed from an elastic material, such as pellethane and the like, that can stretch and contract to vary the distance between first tube  110  and second tube  120 . This region of third tube  130  is referred to herein as variable length section  139 . In the embodiment of  FIGS. 1-4  section  139  forms a “neck” and has a reduced diameter as compared to tubes  110  and  120  and the regions of tube  130  located both distal and proximal to section  139 . In  FIGS. 2-3 , variable length section  139  is distal and adjacent to a bond  135  between third tube  130  and mandrel  140 . This bonded area  135  does not change length, although the tapered variable length section  139  does. In  FIG. 4 , bonded area  135  is omitted. As is discussed in more detail with respect to  FIGS. 15A-B , bonded area  135  can limit the size of variable length section  139  and thus the amount by which catheter  100  can change length. 
         [0038]    Variable length section  139 , among other functions, allows expandable member  150  to more closely fit against the catheter shaft during withdrawal from a vertebral body. Variable length section  139  also allows distal end of catheter  102  to extend in a longitudinal direction such that expandable member  150  will not extend past distal end of catheter  102 . Expandable member  150  can be configured as a balloon (as shown in  FIG. 4 ) that is coupled to third tube  130  at a distal coupling location  151  and a proximal coupling location  152 . Distal coupling location  151  can be at the distal end of second tube  120  and proximal coupling location  152  begins (when viewing distal to proximal) at first tube  110  and can extend any additional distance proximally. Here proximal coupling location  152  extends proximally past proximal end  134  of first tube  110 . In many embodiments proximal coupling location  152  can extend proximally from a proximal terminus  115  of open beveled end  113  (i.e., the proximal terminus of the beveled face). 
         [0039]    Any number of radiopaque (RO) markers can be added to catheter  100  to aid in visualization during the medical procedure. In this embodiment, a distal RO marker  108  is located just proximal to distal coupling section  151 . A proximal RO marker  109  is located just distal to proximal coupling location  152 . RO markers  108  and  109  can be in the form of bands wrapped about the exterior of third tube  130  and can be affixed with adhesive. Other configurations and methods of attachment for RO markers  108  and  109  are known in the art and can be used as well. Placement in these locations can assist the medical professional in locating the limits of expandable member  150  prior to inflation to create the interior cavity in the cancellous bone. 
         [0040]    A mandrel  140  (which can also be referred to as a stylet or stiffening member) is received within the lumen  122  of second tube  120 , passes through beveled end  113  and into first lumen  112 . The width (or diameter) of mandrel  140  is less than that of first lumen  112  to allow the inflation medium to pass through lumen  112  and port  106 . The width (or diameter) of mandrel  140  is also less than that of second tube lumen  122  to allow second tube  120  to slide back and forth along mandrel  140  during inflation and deflation of member  150 . In this respect, mandrel  140  serves as a guide that maintains second tube  120  in the proper alignment throughout movement. 
         [0041]    First tube  110  and second tube  120  can be formed from a metal or polymer that is of sufficient rigidity to withstand the pressures created during inflation of expandable member  150 . First tube  110  and second tube  120  can be formed from the same or different materials. In some embodiments, first tube  110  and second tube  120  are formed from Pebax  70 D. In other embodiments, first tube  110  is stainless steel and second tube  120  is Pebax  70 D. Other variations are possible. Because third tube  130  is formed from an elastic material, in most embodiments, third tube  130  is generally not capable of maintaining second tube  120  in position with respect to first tube  110 . Therefore, in most embodiments mandrel  140  can also be formed of a rigid metal (e.g., stainless steel, nitinol, etc.) or polymer that is stiff enough to hold second tube  120  in position without substantial lateral deflection with respect to first tube  110 . Mandrel  140  can be formed from a metal or polymer with the same or greater stiffness than the material(s) of first tube  110  and/or second tube  120 . 
         [0042]    In many embodiments expandable member  150  has elastic properties which allow it to stretchably expand and contract. In some embodiments, expandable member  150  may be made of thermoplastic polyurethane (TPU). Expandable member  150  can also be formed from an inelastic or substantially inelastic balloon that resists significant stretching, as are known in the art. Also, expandable member  150  may be made of a single component/layer or multiple components/layers which allow it to expand and contract as desired for the particular medical procedure. 
         [0043]    Expandable member  150  is operable to change configurations from a collapsed first configuration to an inflated second configuration. An example of an inflated second configuration can be seen in  FIG. 4 . The collapsed first configuration is ideal for the introduction of catheter device  100  into a vertebral body of the patient because expandable member  150  is in its most compact form.  FIG. 7  is an end-on view depicting an example embodiment of expandable member  150  in a collapsed first configuration with four curved pleats or folds  154  that allow for compact delivery. In an example bone compaction procedure, a hole is first created (e.g., drilled) in the cortical layer surrounding the cancellous bone. Catheter  100 , with expandable member  150  not inflated and folded against the catheter shaft, is then inserted (e.g., from a cannula) through the hole in the cortical layer and into the interior region where the cancellous bone is located. 
         [0044]    Expandable member  150  can then be filled with an inflation medium in order to reach the inflated second configuration of  FIG. 4 . Pleats  154  ( FIG. 7 ) will unravel or unfold when subjected to interior pressure due to outflow of the inflation medium from port  106  and into the interior space of expandable member  150 . A high degree of force can be generated by expandable member  150  to allow it to push and compact the cancellous bone. Expandable member  150  should therefore be of sufficient strength and durability to compact cancellous bone without rupturing during inflation. This process is described in relation to  FIGS. 22A-26 , described further below. 
         [0045]    When filled with inflation medium (e.g., saline) expandable member  150  can expand in both a longitudinal direction (to increase length) and a radial direction (to increase circumference or perimeter). Expansion in a longitudinal direction causes third tube  130  to stretch while second tube  120  is advanced distally. For deflation, the medium may be removed from expandable member  150  by reversing the flow of the inflation medium after the conclusion of the cancellous bone compacting procedure such that the inflation medium passes back through port  106  and into first tube lumen  112 . In doing so, expandable member  150  will deflate from the inflated second configuration to a deflated third configuration. The deflated third configuration is also accompanied by contraction of third tube  130  in variable length section  139  from its expanded state in the inflated second configuration to a configuration similar to the first configuration. Second tube  120  moves proximally as well towards the position of the first configuration (closer to beveled end  113  of first tube  110 ). 
         [0046]    The removal or extraction of catheter device  100  from the cancellous bone area (e.g., back into a cannula) occurs through the same opening in the cortical bone through which it was introduced. However, it is difficult to return expandable member  150  to a folded state resembling that prior to inflation (e.g., that of  FIG. 7 ). When using some conventional compaction catheters with a narrow opening in the cortical bone, there is minimal room for withdrawal of catheter  100  and, as a result, expandable member  150  may begin to bunch up within the vertebral cavity adjacent the cortical opening, which can inhibit its removal from the vertebral body. This undesirable result can be avoided in certain embodiments by variable length section  139 . If expandable member  150  begins to bunch up as catheter  100  is withdrawn then expandable member  150  will pull on catheter  100  and cause variable length section  139  to advantageously elongate. The elongation will allow for longitudinal elongation (or extension or expansion) of catheter  100 , which accordingly allows expandable member  150  to reside more closely against the catheter shaft and facilitate withdrawal through the cortical opening. 
         [0047]      FIGS. 8-9  are partial cross-sectional side views of another example embodiment of catheter  100 , without and with a partially inflated expandable member  150 , respectively. In this embodiment, catheter  100  includes a spacer or shim  148  near open beveled end  113 . Shim  148  can be configured to provide interior support, alignment assistance, or spacing between components. For example, the neck in section  139  can cause mandrel  140  to be positioned against the interior sidewall of lumen  122  opposite to and facing the opening in beveled end  113 , which in turn can allow the distal section of catheter  100  having second tube  120  to align around mandrel  140  in a position that is displaced relative to first tube  100 . Shim  148  can adjust the position of mandrel  140  so that a center longitudinal axis of mandrel  140  is aligned with a center longitudinal axis of first tube  110 , and thus any alignment of second tube  120  around mandrel  140  will also align with first tube  110 . 
         [0048]    The embodiment of  FIGS. 8-9  also differs from that of  FIGS. 1-4  in the position of proximal RO marker  109 , which is now located directly over variable length section  139  adjacent and distal to inflation port  106 . 
         [0049]    Also provided herein are example embodiments of methods of manufacturing catheter device  100 . These methods typically involve a number of steps that are described below. Those of ordinary skill in the art will recognize from this description that the order in which these steps can be carried out can vary from the order described here. 
         [0050]      FIG. 10  is a flowchart depicting an example embodiment of a manufacturing process  1000 . In general, manufacturing process  1000  will include the general steps of construction of the catheter shaft at  1001 , then bonding of the proximal end of an expandable member at  1100 , and then bonding of the distal end of an expandable member at  1200 . Each of these general steps can include a number of sub-steps (e.g.,  1002 - 1010 ,  1102 - 1108 , and  1202 - 1208 ). These sub-steps can be exchanged, omitted, expanded, or repeated as necessary. Likewise steps  1100  and  1200  can be performed in the reverse order. The steps and sub-steps described above will now be described in greater detail with specific example embodiments shown in  FIGS. 11-21 . 
         [0051]    A first step in the manufacturing of catheter shaft  1001  can be sub-step  1002  where an optional shim spacer  148  (seen in  FIGS. 8, 9 ) is assembled with first tube  110  and mandrel  140 . As depicted in  FIG. 11A , mandrel  140  can first be guided into first tube lumen  112  and shim spacer  148  (obscured) can subsequently be placed in between an interior surface of first tube  110  and mandrel  140 . In embodiments where shim spacer  148 , mandrel  140  and first tube  110  are all metal, the components can be resistance welded or soldered together. In embodiments where one or more of shim spacer  148 , mandrel  140  and first tube  110  are not metal, one or more adhesive materials can be used to secure positioning of the components. In some embodiments shim spacer  148  is cut from another piece of tubing using a laser. 
         [0052]    Once a secured assembly of first tube  110 , shim spacer  148 , and mandrel  140  is prepared, then a proximal tube  131  can be bonded to first tube  110  (sub-step  1004  of  FIG. 10 ) by first sliding it over and around the assembly. Alignment of, for example, a 14 mm long proximal tube  131  can be achieved by positioning the proximal 12 mm length of proximal tube  131  around first tube  110  while the distal 2 mm length can be positioned around the mandrel  140 . In other embodiments different positions can be used. 
         [0053]      FIG. 11B  shows an example embodiment of a heat shrink tube  160  positioned around the secured assembly of first tube  110 , shim spacer  148 , and mandrel  140  along with proximal tube  131  in the described position. Once the heat shrink tube  160  is in place it can be heated such that it will cause proximal tube  131  to bond with first tube  110 . In an example embodiment heat can be applied from the proximal end of heat shrink tube  160  while rotating the assembly about its longitudinal axis. The heat is moved distally until reaching the proximal terminus of open beveled end  113 . Here, heat is not applied to the tubing over open beveled end  113 . Heat shrink tube  160  can then be removed by peeling it from the assembly. The assembly can then be examined to ensure that proximal tube  131  is uniformly bonded with first tube  110 . 
         [0054]      FIG. 12A  is a top view showing an example embodiment of the assembly with heat shrink tube  160  removed. At this stage proximal tube  131  is not yet bonded at its distal end. Proximal tube  131  can be cut such that an opening over open beveled end  113  is created (sub-step  1006  of  FIG. 10 ). The opening can be the same size as open beveled end  113  or can have a different size. The assembly can be examined to ensure that the cut portion of proximal tube  131  has left an adequate opening over open beveled end  113 . 
         [0055]      FIG. 12B  depicts the assembly with another heat shrink tube  160  around proximal tube  131  after proximal tube  131  has been cut. Heat shrink tubing  160  can then be heated in a manner similar to that already described, starting at the proximal end and moving distally while rotating about a longitudinal axis of the assembly. In this step, the distal end of proximal tube  131  is heated such that it bonds to mandrel  140 . Heat shrink tube  160  can then be removed, for example, by peeling it away from the assembly. After removal of heat shrink tube  160 , the assembly can be examined to ensure that proximal tube  131  is fully and uniformly bonded with guiding mandrel  140 . If imperfections such as “cloudiness” exist in the bond then another heat shrink tube  160  can be positioned and heated. The process can be repeated as necessary to create the uniform bond depicted in  FIG. 12C . 
         [0056]      FIGS. 13A-B  show an example embodiment of preparing proximal tube  131  for bonding with distal tube  132  (shown in later figures). In the example embodiment a 1.0 mm+/−0.5 mm length of proximal tube  131  can be measured from the distal end of first tube  110  distally along mandrel  140 . At that location proximal tube  131  can be cut and material  133  located distal to the cut can be removed. A check may be made of proximal tube  131  from the opening over beveled end  113  to the proximal end of proximal tube  131  to determine whether it is within a desired range, for example 7.0 mm+/−0.5 mm. 
         [0057]    Distal tube  132  can now be prepared for bonding to proximal tube  131  by cutting or otherwise forming an arc shape (e.g., a crescent) in its proximal end as seen in  FIG. 14  (sub-step  1008  of  FIG. 10 ). 
         [0058]      FIGS. 15A-B  show an example embodiment of the creation of a bonded area  135  between proximal tube  131  and distal tube  132  to create third tube  130  (sub-step  1010  of  FIG. 10 ). Initially distal tube  132  can be slid around mandrel  140  such that it overlaps a portion of proximal tube  131  and the cut at the distal end of proximal tube  131  aligns at least partially with the cut at the proximal end of distal tube  132 , creating an inflation port  106  aligned at least partially over open beveled end  113 . A heat shrink tube  160  (not shown) can be placed over the assembly and heated such that proximal tube  131  and distal tube  132  are heated and bond at bonded area  135 . The bonded area  135  (or “bond”) can include a bond between tubes  131 ,  132  and underlying mandrel  140 . Heating can begin at distal tube  132 , for example at a location 1 mm distal to the terminus of proximal terminus  115  and move proximally. In some embodiments, heating does not occur past the distal end of proximal tube  131 . This process can be repeated as necessary to create a seamless bond, by which third tube  130  is fabricated and by which third tube  130  is bonded to mandrel  140 . The bond  135  (see also  FIG. 2 ) of third tube  130  to mandrel  140  assists in limiting the degree by which variable length section  139  will stretch. 
         [0059]    A marker band  109  in some embodiments can be placed in position over the welded portion of mandrel  140  and first tube  110  such that it does not cover or otherwise substantially obstruct inflation port  106 . 
         [0060]    Alternative fixation techniques can be used to create bonded area  135  such as adhesives, and others, depending on the type of material used in proximal tube  131  and distal tube  132  and the inherent physical properties of each. 
         [0061]    Turning now to general steps  1100  and  1200  of  FIG. 10 , expandable member  150  can have a proximal leg  155  and a distal leg  156  such that the legs can be bonded and/or secured to the catheter shaft (see  FIG. 16 ). In some embodiments proximal leg  155  and distal leg  156  can be trimmed to desired dimensions such that they are square cuts, perpendicular to a longitudinal axis running lengthwise through the center of expandable member  150  and creating a circular cross sectional profile. Proximal leg  155  can be trimmed, for example about 7 mm in length, and distal leg  156  can be trimmed, for example, about 5 mm in length. Expandable member  150  in the example embodiment has tapered portions at both its proximal and distal ends which taper from a larger cross-sectional area to the smaller cross-sectional area of proximal leg  155  and distal leg  156  respectively, and the middle section can have a substantially uniform cross-sectional area. 
         [0062]      FIG. 16  is a perspective view depicting a subsequent step in manufacturing. Here, expandable member  150  with proximal leg  155  and distal leg  156  has been slid over third tube  130  until the distal transition  201  of proximal leg  155  is approximately aligned with the proximal terminus  115  of open beveled end  113  such that inflation port  106  (not labeled) is left unobstructed (sub-step  1102  of  FIG. 10 ). Heat shrink tube  160  can be advanced distally over the catheter shaft such that it slides over proximal leg  155  to its distal transition  201  (sub-step  1104  of  FIG. 10 ). 
         [0063]      FIG. 17  shows an example embodiment of an initial proximal leg bonding process to bond proximal leg  155  to third tube  130 , and in some embodiments first tube  110  and sheath  104 . After the heat shrink tube  160  is placed over proximal leg  155 , heat shrink tube  160  and proximal leg  155  assembly can be positioned such that a cross section of proximal leg  155  is perpendicular with a longitudinal axis running through the center of expandable member  150  and is parallel and aligned with a heating element  170 . Heating of heating element  170  can cause heat shrink tube  160  to shrink and transfer heat to proximal leg  155  and cause it to fuse and/or bond to third tube  130  (sub-step  1106  of  FIG. 10 ) at proximal coupling location  152 . When the heating process is finished, the operator can remove heat shrink tube  160  by peeling it from proximal leg  155  (sub-step  1108  of  FIG. 10 ). 
         [0064]      FIG. 18  shows an example embodiment of the assembly after a first proximal leg bonding process. In order to reduce the width or diameter of the proximal leg bond and/or also to improve the taper of the bond, a second proximal leg bonding process may be applied by repeating the same steps with a smaller or similarly sized heat shrink tube. This is shown in  FIG. 19 . The process can be iteratively repeated with similarly sized or sequentially smaller diameter heat shrink tubes, or any combination thereof. The reduced bond diameter and improved taper of proximal leg  155  can offer a cross-sectional profile that is less intrusive in medical procedures. 
         [0065]      FIG. 20  is a side view depicting a next step in the manufacturing process where second tube  120  has been inserted into third tube  130  such that mandrel  140  is situated in second tube inner lumen  122  (not labeled). In many embodiments second tube  120  can be advanced along mandrel  140  in a proximal direction until reaching the location where third tube  130  is bonded to mandrel  140 . The resulting assembly can then be put through a distal leg bonding process. Mandrel  140  can be trimmed to a specified length if necessary at various steps herein. 
         [0066]      FIG. 21  shows the distal leg bonding process setup where expandable member  150  has been placed in a proximal position to a proximal heat shield  172  (sub-step  1202  of  FIG. 10 ). In the example embodiment heat shrink tubing  160  is advanced proximally around distal leg  156  (sub-step  1204  of  FIG. 10 ). Expandable member  150  can be adjacent and touching proximal heat shield  172 . In this configuration heat shrink tubing  160  should be exposed at the distal side of proximal heat shield  172  for heat treatment from heating element  170  which can be adjusted such that it touches heat shrink tubing  160 . Shrink tubing  160  can extend slightly past proximal heat shield  172 . In the example embodiment this slight extension is 1 mm or less. Expandable member  150  can be protected by proximal heat shield  172  while distal leg  156  is exposed for heat treatment within heat shrink tubing  160  (sub-step  1206  of  FIG. 10 ). Once bonded, heat shrink tubing  160  can be removed (sub-step  1208  of  FIG. 10 ) and replaced with another, smaller heat shrink tubing  160  and the process repeated once, twice, or as many times as needed to achieve the desired size and shape. Distal leg bonding process can bond distal leg  156  to third tube  130  and second tube  120  at distal coupling location  151  ( FIG. 4 ). In some embodiments, the distal leg bond can be sufficient to allow bonded distal leg  156 , second tube  120  and third tube  130  to be trimmed to 0.5 mm length from expandable member  150 . This short length can provide a medical professional with additional precision in performing medical procedures with expandable member  150 . 
         [0067]    In certain embodiments, expandable member  150  and third tube  130  (including proximal tube  131  and distal tube  132  when present) are constructed of pellethane. Although the embodiments disclosed herein are not limited to pellethane, it has been found that pellethane exhibits superior characteristics that make it highly suitable for use as these components. Pellethane exhibits the appropriate elasticity for use as the expandable member. Pellethane also has a melting temperature, viscosity when melted, and adhesive (and cohesive) characteristics that are suitable for bonding third tube  130  to expandable member  150 , first tube  110 , mandrel  140 , and second tube  120  (as well as for bonding proximal tube  131  to distal tube  132  in those embodiments). The use of pellethane for third tube  130  can significantly facilitate the creation of the bond with mandrel  140 , as that bond can be as short as 1 mm or less in certain embodiments. Although different pellethanes can be used, it has been found that pellethane  90 A exhibits optimal performance in certain embodiments. 
         [0068]      FIGS. 22-26  show an example embodiment of a procedure using the apparatus described herein.  FIGS. 22A-B  show an example embodiment of a side perspective and angled perspective of a normal spinal column.  FIGS. 23A-B  shows an example embodiment of a side perspective and angled perspective of a spinal column with a fracture  180  in one vertebrae. This type of fracture may be more likely to occur for example if cancellous bone within the vertebrae deteriorates and no procedure is performed to reinforce the bone using an apparatus as described herein.  FIGS. 24-25  show an example embodiment of a spinal column wireframe and diagram respectively with expandable member  150  inflated within the bone to compress cancellous bone.  FIG. 26  shows an example embodiment of a spinal column diagram with bone cement injected into the bone after deteriorating cancellous bone has been compressed using the apparatus described herein. 
         [0069]    Where a range of values is provided, it is noted that each intervening value, to the tenth of the unit of the lower limit unless the context clearly dictates otherwise, between the upper and lower limit of that range and any other stated or intervening value in that stated range, is encompassed within the disclosure and can be claimed as an sole value or as a smaller range. Where the stated range includes one or both of the limits, ranges excluding either or both of those included limits are also included in the disclosure. 
         [0070]    Where a discrete value or range of values is provided, it is noted that that value or range of values may be claimed more broadly than as a discrete number or range of numbers, unless indicated otherwise. For example, each value or range of values provided herein may be claimed as an approximation and this paragraph serves as antecedent basis and written support for the introduction of claims, at any time, that recite each such value or range of values as “approximately” that value, “approximately” that range of values, “about” that value, and/or “about” that range of values. Conversely, if a value or range of values is stated as an approximation or generalization, e.g., approximately X or about X, then that value or range of values can be claimed discretely without using such a broadening term. 
         [0071]    However, in no way should a claim be limited to a particular value or range of values absent explicit recitation of that value or range of values in the claims. Values and ranges of values are provided herein merely as examples. 
         [0072]    While the embodiments are susceptible to various modifications and alternative forms, specific examples thereof have been shown in the drawings and are herein described in detail. It should be understood, however, that these embodiments are not to be limited to the particular form disclosed, but to the contrary, these embodiments are to cover all modifications, equivalents, and alternatives falling within the spirit of the disclosure. Furthermore, any features, functions, steps, or elements of the embodiments may be recited in or added to the claims, as well as negative limitations that define the inventive scope of the claims by features, functions, steps, or elements that are not within that scope.