Abstract:
A ratcheting strut comprising: (a) a ratchet box including a through passage; (b) a first tube sized to extend at least partially through the passage, the first tube including ratchet teeth that engage corresponding ratchet teeth of the ratchet box; (c) a second tube mounted to the ratchet box in parallel with the first tube, the second tube operatively coupled to a second fixation adapter; and (d) a threaded rod operatively coupled to a nut and a first fixation adapter, the threaded rod repositionably mounted to the first tube, where the nut is operatively coupled and repositionable with respect to the first tube.

Description:
RELATED ART 
     Field of the Invention 
       [0001]    The present invention is directed to devices and methods utilized in fracture reduction and, more specifically, to devices and methods providing length adjustment during fracture fixation. 
       INTRODUCTION TO THE INVENTION 
       [0002]    The present invention is directed to devices and methods utilized in fracture reduction and, more specifically, to devices and methods providing length adjustment during fracture fixation. The present invention may include modular (re)movable struts that can be interchanged depending upon the distance to be spanned (i.e., span fracture in a single long bone, or cross the knee joint). In one exemplary embodiment, a ratcheting strut is disclosed that provides for length adjustment during fracture fixation and reduction. 
         [0003]    It is a first aspect of the present invention to provide a ratcheting strut comprising: (a) a ratchet box including a through passage; (b) a first tube sized to extend at least partially through the passage, the first tube including ratchet teeth that engage corresponding ratchet teeth of the ratchet box; (c) a second tube mounted to the ratchet box in parallel with the first tube, the second tube operatively coupled to a second fixation adapter; and, (d) a threaded rod operatively coupled to a nut and a first fixation adapter, the threaded rod repositionably mounted to the first tube, where the nut is operatively coupled and repositionable with respect to the first tube. 
         [0004]    In a more detailed embodiment of the first aspect, the second tube is longitudinally axially offset from the first tube. In yet another more detailed embodiment, the second tube includes a fixed length and is removably coupled to the ratchet box. In a further detailed embodiment, the second tube is removably mounted to the ratchet box, and the second tube is removably mounted to the second fixation adapter. In still a further detailed embodiment, the fixation adapter includes at least one of a ball joint, a ball joint housing, and a ball joint cap. In a more detailed embodiment, the ratchet box includes a first lever repositionable between an engaged position and a disengaged position, the first lever includes the ratchet teeth of the ratchet box, the ratchet teeth of the lever engage the ratchet teeth of the first tube in the engaged position, and the ratchet teeth of the lever do not engage the ratchet teeth of the first tube in the disengaged position. In a more detailed embodiment, a plurality of the ratchet teeth of the first lever each include a profile including an inclined surface and a vertical surface, a plurality of the ratchet teeth of the first tube each include a profile including an inclined surface and a vertical surface, the inclined surfaces of the ratchet teeth of the first lever are substantially parallel to the inclined surfaces of the ratchet teeth of the first tube when in the engaged position, and the vertical surfaces of the ratchet teeth of the first lever are substantially parallel to the vertical surfaces of the ratchet teeth of the first tube when in the engaged position. In another more detailed embodiment, the lever is biased to the engaged position. In yet another more detailed embodiment, the ratchet box includes a first lever repositionable between an engaged position and a disengaged position, and a second lever repositionable between an engaged position and a disengaged position, the first lever includes a first portion of the ratchet teeth of the ratchet box, the second lever includes a second portion of the ratchet teeth of the ratchet box, the ratchet teeth of the ratchet tube include a first row and a second row, the first portion of the ratchet teeth of the first lever engage the first row of the ratchet teeth of the first tube in the engaged position, the second portion of the ratchet teeth of the second lever engage the second row of the ratchet teeth of the first tube in the engaged position, the first portion of the ratchet teeth of the first lever do not engage the first row of the ratchet teeth of the first tube in the disengaged position, and the second portion of the ratchet teeth of the second lever do not engage the second row of the ratchet teeth of the first tube in the disengaged position. In still another more detailed embodiment, a plurality of the first portion of the ratchet teeth each include a profile including an inclined surface and a vertical surface, a plurality of the second portion of the ratchet teeth each include a profile including an inclined surface and a vertical surface, a plurality of the first row of the ratchet teeth each include a profile including an inclined surface and a vertical surface, a plurality of the second row of the ratchet teeth each include a profile including an inclined surface and a vertical surface, the inclined surfaces of first and second rows are parallel to one another, and the inclined surfaces of the first and second portions are parallel to one another when the first and second levers are both in the engaged position. 
         [0005]    In yet another more detailed embodiment of the first aspect, the ratchet box includes a first lever repositionable between an engaged position and a disengaged position, and a second lever repositionable between an engaged position and a disengaged position, the first lever includes a first portion of the ratchet teeth of the ratchet box, the second lever includes a second portion of the ratchet teeth of the ratchet box, the ratchet teeth of the ratchet tube include a first row and a second row, an interaction between the first portion of the ratchet teeth and the first row of ratchet teeth prohibit movement between the ratchet box and the ratchet tube in a first direction when the first lever is in the engaged position, but allows movement between the ratchet box and the ratchet tube in a second direction, opposite the first direction, when the first lever is in the engaged position and the second lever is in the disengaged position, and an interaction between the second portion of the ratchet teeth and the second row of ratchet teeth prohibit movement between the ratchet box and the ratchet tube in the second direction when the second lever is in the engaged position, but allows movement between the ratchet box and the ratchet tube in the first direction when the second lever is in the engaged position and the first lever is in the disengaged position. In still another more detailed embodiment, the second tube is at least partially hollow and includes a cavity adapted to be partially occupied by the first tube, and the first tube is at least partially hollow and includes a cavity adapted to be partially occupied by the threaded rod. In a further detailed embodiment, the first tube, the second tube, and the threaded rod telescopically interact with one another. In still a further detailed embodiment, the threaded rod is removably mounted to the second fixation adapter, and the fixation adapter includes at least one of a ball joint, a ball joint housing, and a ball joint cap. In a more detailed embodiment, the threaded rod is operatively coupled to a friction sleeve that is received within the first tube. In a more detailed embodiment, the threaded rod is removably mounted to a post cap that is received within the first tube, and the friction sleeve is removably mounted to the post cap. In another more detailed embodiment, the first tube includes a tube mount coupled to an end thereof, the tube mount includes a through orifice and a circumferential channel that receives a projection from the nut so that the nut rotationally engages the tube mount, the threaded rod is sized to extend through the tube mount orifice, and threads of the threaded rod are sized to engage threads of the nut so that rotation of the nut results in longitudinal repositioning of the threaded rod. 
         [0006]    It is a second aspect of the present invention to provide a bone fracture fixation device comprising: (a) a first tube being repositionable with respect to a second tube in predetermined longitudinal increments, wherein the first tube is associated with a first actuator biased to engage the second tube to retard motion of the first tube with respect to the second tube in a first direction, where the first tube and the second tube extend in opposite directions, and where at least one of the first tube and the second tube includes an extension operatively coupled thereto that is repositionable to increase an aggregate length of at least one of the first tube and the second tube, wherein the extension is repositionable in longitudinal increments smaller than the predetermined longitudinal increments. 
         [0007]    In a more detailed embodiment of the second aspect, the longitudinal increments of the extension are infinitely small. In yet another more detailed embodiment, the second tube is longitudinally axially offset from the first tube. In a further detailed embodiment, the first tube and the second tube each include a fixed length, and where the first tube includes a hollow interior to accommodate at least a portion of the second tube. In still a further detailed embodiment, the second tube is removably mounted to the first tube, and the second tube is removably mounted to a fixation adapter. In a more detailed embodiment, the fixation adapter includes at least one of a ball joint, a ball joint housing, and a ball joint cap. In a more detailed embodiment, the actuator includes a first lever repositionable between an engaged position and a disengaged position, the first lever includes ratchet teeth, the ratchet teeth of the first lever engage ratchet teeth of the second tube in the engaged position, and the ratchet teeth of the first lever do not engage the ratchet teeth of the second tube in the disengaged position. In another more detailed embodiment, a plurality of the ratchet teeth of the first lever each include a profile including an inclined surface and a vertical surface, a plurality of the ratchet teeth of the second tube each include a profile including an inclined surface and a vertical surface, the inclined surfaces of the ratchet teeth of the first lever are substantially parallel to the inclined surfaces of the ratchet teeth of the second tube when in the engaged position, and the vertical surfaces of the ratchet teeth of the first lever are substantially parallel to the vertical surfaces of the ratchet teeth of the second tube when in the engaged position. 
         [0008]    In yet another more detailed embodiment of the second aspect, the first tube is associated with a second actuator biased to engage the second tube to retard motion of the first tube with respect to the second tube in a second direction, opposite the first direction, the actuator is repositionable between an engaged position and a disengaged position, the second actuator is repositionable between an engaged position and a disengaged position, the second tube includes a first series of teeth and a second series of teeth, the first actuator engages the first series of teeth in the engaged position, the second actuator engages the second series of teeth in the engaged position, the first actuator does not engage the first series of teeth in the disengaged position, and the second actuator does not engage the second series of teeth in the disengaged position. In still another more detailed embodiment, a plurality of the first series of the teeth each include a profile including an inclined surface and a vertical surface, a plurality of the second series of the teeth each include a profile including an inclined surface and a vertical surface, the first actuator includes at least one tooth including a profile including an inclined surface and a vertical surface, the second actuator includes at least one tooth including a profile including an inclined surface and a vertical surface, the inclined surfaces of the first and second series of teeth are parallel to one another, and the inclined surfaces of the at least one tooth of the first and second actuators are parallel to one another when the first and second actuators are both in the engaged position. In a further detailed embodiment, the first tube is at least partially hollow and includes a cavity adapted to be partially occupied by the second tube, and the second tube is at least partially hollow and includes a cavity adapted to be partially occupied by the extension. In still a further detailed embodiment, the first tube, the second tube, and the extension telescopically interact with one another. In a more detailed embodiment, the extension is removably mounted to a first fixation adapter, and the first fixation adapter includes at least one of a ball joint, a ball joint housing, and a ball joint cap. In a more detailed embodiment, the extension is operatively coupled to a friction sleeve that is received within the second tube. In another more detailed embodiment, the extension is removably mounted to a post cap that is received within the first tube, and the friction sleeve is removably mounted to the post cap. In yet another more detailed embodiment, the second tube includes a tube mount coupled to an end thereof, the tube mount includes a through orifice and a circumferential channel that receives a projection from a nut so that the nut rotationally engages the tube mount, the extension is sized to extend through the tube mount orifice, and threads of the extension are sized to engage threads of the nut so that rotation of the nut results in longitudinal repositioning of the extension with respect to the first and second tubes. 
         [0009]    It is a third aspect of the present invention to provide a method of using a fracture fixation device that includes opposing longitudinal tubes that are repositionable with respect to one another to increase and decrease a total distance between opposing ends of the longitudinal tubes, the method comprising: (a) repositioning a first of the longitudinal tubes with respect to a second of the longitudinal tubes in a first direction so that a first series of teeth associated with the first longitudinal tube slides upon a first series of teeth associated with the second longitudinal tube; and, (b) repositioning a first blocking actuator associated with at least one of the first and second longitudinal tubes to discontinue engagement of the first series of teeth of the first longitudinal tube with the first series of teeth of the second longitudinal tube in order to reposition the first longitudinal tube with respect to the second longitudinal tube in a second direction, opposite the first direction 
         [0010]    In a more detailed embodiment of the third aspect, the step of repositioning the first longitudinal tube with respect to the second longitudinal tube in the first direction includes repositioning a second blocking actuator associated with at least one of the first longitudinal tube and the second longitudinal tube to discontinue engagement of a second series of teeth of the first longitudinal tube with a second series of teeth of the second longitudinal tube. In yet another more detailed embodiment, the step of repositioning a first blocking actuator associated with at least one of the first and second longitudinal tubes includes repositioning a second blocking actuator associated with at least one of the first longitudinal tube and the second longitudinal tube to engage a second series of teeth of the first longitudinal tube with a second series of teeth of the second longitudinal tube. In a further detailed embodiment, the method further includes repositioning a first extension operatively coupled to at least one of the longitudinal tubes, where repositioning of the first longitudinal tube with respect to the second longitudinal tube is carried out in predetermined longitudinal increments defined by the dimensions of the first and second series of teeth, and repositioning of the first extension is carried out in longitudinal increments smaller than the predetermined longitudinal increments provided by the first and second series of teeth. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIG. 1  is an elevated perspective view of an assembled first exemplary ratcheting strut in accordance with the instant disclosure. 
           [0012]      FIG. 2  is an exploded view of the first exemplary ratcheting strut of  FIG. 1  without the thumb screw. 
           [0013]      FIG. 3  is a cross-sectional view of the first exemplary ratcheting strut of  FIG. 1  taken along line  3 - 3 . 
           [0014]      FIG. 4  is an elevated perspective view of the exemplary ratchet tube of  FIG. 1 . 
           [0015]      FIG. 5  is an elevated perspective view of the exemplary ratchet box of  FIG. 1 . 
           [0016]      FIG. 6  is another elevated perspective view of the exemplary ratchet box of FIG. 
           [0017]      FIG. 7  is a cross-sectional view of the first exemplary ratcheting box of  FIG. 5  taken along line  7 - 7 . 
           [0018]      FIG. 8  is a magnified view of the ratchet box and internal components shown in  FIG. 3 . 
           [0019]      FIG. 9  is a magnified view of the ratchet box and internal components shown in  FIG. 8 . 
           [0020]      FIG. 10  is an elevated perspective view showing assembly of several of the components of  FIG. 1 . 
           [0021]      FIG. 11  is an elevated perspective view of the thumb screw in  FIG. 1 . 
           [0022]      FIG. 12  is an end view of the tube mount of  FIG. 1 . 
           [0023]      FIG. 13  is an elevated perspective view of the tube mount of  FIG. 1 . 
           [0024]      FIG. 14  is an elevated perspective view of the nut of  FIG. 1 . 
           [0025]      FIG. 15  is an end view of the nut of  FIG. 1 . 
           [0026]      FIG. 16  is a cross-sectional view of the components of  FIG. 10  taken along line  16 - 16 . 
           [0027]      FIG. 17  is a magnified view of the ratchet box and other components shown in  FIG. 3 . 
           [0028]      FIG. 18  is an elevated perspective view of an assembled second exemplary ratcheting strut in accordance with the instant disclosure. 
           [0029]      FIG. 19  is an exploded view of the second exemplary ratcheting strut of  FIG. 18 . 
           [0030]      FIG. 20  is a cross-sectional view of the second exemplary ratcheting strut of  FIG. 18  taken along line  20 - 20 . 
           [0031]      FIG. 21  is an elevated perspective view of the ratchet tube of  FIG. 18 . 
           [0032]      FIG. 22  is a magnified view of the ratchet box and internal components shown in  FIG. 20 . 
           [0033]      FIG. 23  is an elevated perspective view of the ratchet box of  FIG. 18 . 
           [0034]      FIG. 24  is another elevated perspective view of the ratchet box of  FIG. 18 . 
           [0035]      FIG. 25  is a cross-sectional view of the ratchet box of  FIG. 20  taken along line  25 - 25 . 
           [0036]      FIG. 26  is an elevated perspective view of the cross-section of  FIG. 25 . 
           [0037]      FIG. 27  is an elevated perspective view of the nut of  FIG. 18 . 
           [0038]      FIG. 28  is another elevated perspective view of the nut of  FIG. 18 . 
           [0039]      FIG. 29  is an elevated perspective view of an assembled third exemplary ratcheting strut in accordance with the instant disclosure. 
           [0040]      FIG. 30  is an exploded view of the third exemplary ratcheting strut of  FIG. 29 . 
           [0041]      FIG. 31  is a cross-sectional view of the third exemplary ratcheting strut of  FIG. 29  taken along line  31 - 31 . 
           [0042]      FIG. 32  is an elevated perspective view of the ratchet box of  FIG. 29 . 
           [0043]      FIG. 33  is a cross-sectional view of the ratchet box of  FIG. 32  taken along line  33 - 33 . 
           [0044]      FIG. 34  is an elevated perspective view of the threaded post of  FIG. 29 . 
       
    
    
     DETAILED DESCRIPTION 
       [0045]    The exemplary embodiments of the present disclosure are described and illustrated below to encompass to devices and methods utilized in fracture reduction and, more specifically, to devices and methods providing length adjustment during fracture fixation. Of course, it will be apparent to those of ordinary skill in the art that the embodiments discussed below are exemplary in nature and may be reconfigured without departing from the scope and spirit of the present disclosure. However, for clarity and precision, the exemplary embodiments as discussed below may include optional steps, methods, and features that one of ordinary skill should recognize as not being a requisite to fall within the scope of the present disclosure. 
         [0046]    Referencing  FIGS. 1-17 , a first exemplary ratcheting strut  100  comprises a ratchet box  102  having a longitudinal opening extending therethrough that accommodates throughput of a ratchet tube  104 . In exemplary form, the longitudinal opening is partially defined by a first cylindrical interior wall  106  having a first diameter. A series of fins  110 ,  112  are mounted to the interior wall  106  and extend into the interior of the longitudinal opening, thereby decreasing the cross-sectional area of the opening. In particular, each fin  110 ,  112  extends perpendicularly from the interior wall and includes an arcuate edge that matches the arcuate contour of the interior wall  106 . An innermost edge of each fin  110 ,  112  comprises a geometric chord, where the horizontal cross-section of the interior wall  106  is circular. In this exemplary embodiment, a first pair of fins  110  is diametrically positioned opposite one another to create a horizontal cross-section having a constant width between the opposed pair of fins. Likewise, a second pair of fins  112  is mounted identically to the interior wall  106  as the first pair of fins, but is longitudinally spaced from the first pair of fins. Working together, the interior wall  106  and fins  110 ,  112  allow longitudinal traversal of the ratchet tube  104 , while inhibiting axial rotation of the ratchet tube. 
         [0047]    In this exemplary embodiment, the ratchet tube  104  comprises a cylindrical ring body having a cylindrical exterior surface  120  axially outset from a cylindrical interior surface  122 . In this manner, the interior of the ratchet tube  104  is hollow and has a constant vertical, circular cross-section along its longitudinal length. An exterior surface of the ratchet tube  104  includes the cylindrical exterior surface  120 , as well as a pair of planar surfaces  124  extending longitudinally along a majority of the longitudinal length of the ratchet tube. In exemplary form, these planar surfaces  124  may be formed by planarizing opposing sides of the ring body (i.e., hollow cylindrical tube) to remove material from the outside of the ring body, thereby decreasing the wall thickness of the ring body, but not impacting the dimensions of the cylindrical interior surface  122 . In exemplary form, the material removed from the ring body can be cross-sectionally represented as a first area outlined by a first chord extending between circumferential exterior points at zero degrees and ninety degrees and by the circumferential surface extending between the same points at zero degrees and ninety degrees. Similarly, the second area may be outlined by a second chord extending between one hundred eighty degrees and two hundred seventy degrees and by the circumferential surface extending between the same points at one hundred eighty degrees and two hundred seventy degrees. The planar surfaces  124 , in exemplary form, do not extend along the entire longitudinal length of the ratchet tube  104 , therefore a distal end  126  of the ratchet tube is cylindrical, while the opposing proximal end  128  of the ratchet tube is partially cylindrical. More specifically, a pair of arcuate surfaces  132 ,  134  extends between the planar surfaces  124  to partially define the exterior of the ratchet tube. Each arcuate surface  132 ,  134  is separated from the other cylindrical surface by approximately ninety rotational degrees, except for the distal end  126  where the cylindrical surfaces seamlessly intersect with the cylindrical exterior surface  120 . The dorsal arcuate surface  132  also includes a series of angled depressions  136  that are longitudinally repeated and consistently spaced apart from one another to create a series of angled teeth  138  that are longitudinally inset from the distal and proximal ends  126 ,  128  of the ratchet tube  104 . In exemplary form, each tooth  138  includes a vertical distal surface  144  and an inclined proximal surface  146  that intersects the distal surface to form a horizontal peak  148 . As will be discussed in more detail hereafter, the inclined nature of the proximal surface  146  cooperates with a corresponding surface of a repositionable lever  170  to allow ratcheting action between the lever and the ratchet tube  104 . 
         [0048]    The shape of the ratchet tube  104  allows it to be inserted into the longitudinal opening of the ratchet box  102  so that the proximal end  124  of the ratchet tube  104  is inserted into a proximal opening  156  of the ratchet box  102  and extends through a distal opening  154  prior to insertion of the distal end  126  of the ratchet tube into the interior of the ratchet box. The distal opening  156  is defined by a second cylindrical interior wall  160  having a diameter larger than the first cylindrical interior wall  106 . This second cylindrical interior wall  160  extends proximally until terminating at a distal flange  162  that extends between the cylindrical interior walls  106 ,  160 . It should be noted that the cylindrical interior walls  106 ,  160  are coaxial with one another so that the distal flange  162  has a constant circular cross-section and axial depth. In this exemplary embodiment, the distal flange  162  is operative to inhibit throughput of objects having a diameter larger than the diameter of the first cylindrical interior wall  106 . In addition, the fins  110 ,  112  located on the interior of the first cylindrical interior wall  106  change the longitudinal profile of the longitudinal opening and prohibit throughput of cylindrical objects having a diameter slightly less than the diameter of the first cylindrical interior wall. As mentioned previously, the distal end  126  of the ratchet tube  104  is cylindrical and exhibits a constant exterior diameter, whereas the proximal end  128  and a majority of the longitudinal length of the ratchet tube exhibits a cross-section that is circular with respect to the arcuate surfaces  132 ,  134 , but is rectangular with respect to the planar surfaces  124 . This dual shape (circular and rectangular) profile is also consistent with the dual shape profile on the interior of the cylindrical interior wall  106  taking into account the fins  110 ,  112 . In exemplary form, the exterior diameter (between the arcuate surfaces  132 ,  134 ) of the ratchet tube  104  is slightly less than the internal diameter of the cylindrical interior wall  106 . Likewise, the horizontal width between the opposed fins  110 ,  112  is slightly larger than the horizontal distance between the planar surfaces  124 . As a result, the proximal end  128  of the ratchet tube  104  is able to be longitudinally repositioned along the entire length of the longitudinal opening of the ratchet box  102 , whereas the distal end  126  of the ratchet tube is able to be longitudinally repositioned within only a portion of the longitudinal opening because the distal end cannot pass beyond the fins  110 ,  112 . In this manner, when the proximal end  128  of the ratchet tube  104  is first inserted into the distal opening  156  of the ratchet box  102  and longitudinally repositioned proximally, eventually the distal end  126  of the ratchet tube (where the planar surfaces  124  terminate and the uniform circumferential surface begins) abuts the fins  110 , which prohibit further proximal motion of the ratchet tube. 
         [0049]    In order to fix the position of the ratchet tube  104  with respect to the ratchet box  102 , the lever  170  is repositionably mounted to the ratchet box to selectively engage the ratchet tube. More specifically, the lever  170  comprises an L-shaped beam  172  having a cylindrical pivot orifice  174  that accepts a dowel  176  concurrently seated within a cylindrical dowel orifice  178  in order to mount the lever  170  to the ratchet box  102 . In exemplary form, the dowel  176  is cylindrical and has an external diameter that is slightly larger than the internal diameter of the cylindrical dowel orifice  178 , thus securing the dowel in position via a friction fit. In contrast, the diameter of the cylindrical pivot orifice  174  is slightly larger than the external diameter of the dowel  176 , thereby allowing pivoting motion of the lever  170  around the dowel. 
         [0050]    In this exemplary embodiment, the lever  170  is biased by a spring  180  to engage the ratchet tube  104 . More specifically, the coil spring  180  is seated within a spring receiver  182  of the ratchet box  102 . The spring receiver  182  comprises a ring-shaped depression that circumscribes a cylindrical projection that is adapted to be partially inserted into one end of the coil spring  180 . Similarly, the underside of the lever  170  also includes a spring receiver  184  that likewise comprises a ring-shaped depression that circumscribes a cylindrical projection adapted to be partially inserted into the other end of the coil spring  180 . The bias of the coil spring  180  is selected or set so that when no affirmative pressure is applied by a user to the lever  170 , a head  188  of the lever contacts the ratchet tube  104 . In exemplary form, the head  188  of the lever  170  includes a series of angled teeth  192  that are each formed by the interaction of a vertical proximal surface  194  and an inclined distal surface  196  that intersects the proximal surface to form a peak  198 . In this fashion, the angled teeth  192  of the lever  170  are inclined to match the incline of the angled teeth  138  of the ratchet tube  104 . As a result, when no affirmative pressure is applied by a user to the lever  170 , the ratchet tube  104  may be repositioned proximally so that the inclined surfaces  146 ,  196  ride upon one another (and overcome the spring  180  bias to raise the lever  170 ) successively, thereby allowing the peaks  148 ,  198  to pass one another. In contrast, when no affirmative pressure is applied by a user to the lever  170 , the ratchet tube  104  may not be repositioned distally because the vertical surfaces  144 ,  194  contact one another and do not allow distal motion because the lever remains in the line of travel of the ratchet tube. Accordingly, in order to reposition the ratchet tube  104  distally, a user needs to apply affirmative pressure to the lever  170  and overcome the spring  180  bias, thereby removing the lever from the line of travel of the ratchet tube. When the appropriate distal travel is reached, the user simply discontinues affirmative pressure to the lever  170 , thereby allowing the spring  180  bias to dominate and cause the lever to contact the ratchet tube  104  so that the vertical surfaces  144 ,  194  contact one another and do not allow distal motion. 
         [0051]    The lever  170  may also be locked in position so that the angled teeth  192  engage the angled teeth  138  of the ratchet tube  104 . In order to lock the lever  170  in the position shown in  FIG. 3 , the lever includes a lock orifice  200  that is sized to receive a portion of a thumb screw  204 . The thumb screw  204  includes a knob  206  mounted to a perpendicularly extending, linear projection  208  having threads  210  adapted to engage threads  212  on the inside of a thumb screw orifice  214  extending through the ratchet box  102 . When the projection  208  of the thumb screw  204  is inserted through the thumb screw orifice  214  and lock orifice  200 , the lever  170  is not pivotally repositionable so that the teeth  192  of the lever are out of the line of travel of the teeth  138  of the ratchet tube  104 . Consequently, to pivot the lever  170  so that the teeth  192  of the lever  170  are out of the line of travel of the teeth  138  of the ratchet tube  104 , the thumb screw  204  needs to be positioned so that the projection  208  is no longer received within the lock orifice  200 . After the thumb screw  204  is positioned so that the projection  208  is no longer received within the lock orifice  200 , the lever  170  may be repositioned by application of affirmative pressure to overcome the bias of the spring  180 , thereby pivoting the lever so that the teeth  192  of the lever are out of the line of travel of the teeth  138  of the ratchet tube  104 . 
         [0052]    When the ratchet tube  104  is repositioned with respect to the ratchet box  102 , other components mounted to the ratchet tube are also repositioned. In this exemplary embodiment, a tube mount  220  is coupled to the proximal end  128  of the ratchet tube via a friction fit. It should be understood, however, that other means of attachment may be used such as, without limitation, adhesives, set screws, and welds. In this manner, longitudinal motion of the ratchet tube  104  causes longitudinal motion of the tube mount  220  and vice versa. The tube mount  220  includes a through opening  222  that accommodates longitudinal movement of the ratchet tube  104  independent of movement of the tube mount. A distal end  224  of the tube mount includes a cylindrical collar  226  that circumscribes the proximal end  128  of the ratchet tube  104 . On the interior of this collar  226  is a flange  228  that provides an abutment surface against which the exposed proximal end  128  of the ratchet tube contacts when fully seated within the collar. The flange  228  also operates to change the profile of the through opening  222  from circular along the collar  226 , to a narrower hybrid profile. This hybrid profile is defined by a pair of parallel, planar surfaces  230  bridged by a pair of arcuate surfaces  232  that extend longitudinally along a sleeve  236  integrally formed with the flange  228  and collar  226 . An exterior surface of the sleeve  236  is cylindrical and smooth, but for a circumferential trench  240  and a radial through opening  242 , where the radial through opening extends into the through opening  222  but the circumferential trench does not. The trench  240  is adapted to partially receive a set screw mounted to a nut  250  that is mounted to and rotationally repositionable with respect to the tube mount  220 . 
         [0053]    In exemplary form, the nut  250  circumscribes a portion of the sleeve  236  and is rotationally repositionable with respect to the sleeve. The nut also includes one or more set screw orifices  252  open to the cylindrical exterior surface  254  that extend into a hollow interior  258 , which includes proximal and distal openings  260 ,  262 . The exterior surface  254  also includes a pair of rounded projections  266  that are utilized to grasp the nut  250  and facilitate rotation of the nut with respect to the sleeve  236 . In this exemplary embodiment, the distal opening  262  allows access to a cylindrical cavity defined by a circumferential interior wall  268 . At the proximal end of this interior wall  268  is a flange  272  that provides an abutment surface against which the exposed proximal end of the sleeve  236  contacts when fully seated within the nut  250 . The flange  272  also operates to change the profile of the hollow interior  258  from circular along the interior wall  268 , to a narrower hybrid profile. This hybrid profile is defined by a pair of parallel surfaces  276  tapped to create threads and bridged by a pair of arcuate surfaces  278  that extend longitudinally until reaching a proximal end  280  of the nut  250 . The parallel, tapped surfaces  276  are adapted to be engaged by a threaded post  284  that extends through the nut  250 , the tube mount  220 , and partially through an interior of the ratchet tube  104 . 
         [0054]    By way of example, the threaded post  284  comprises a cylinder having a cylindrical exterior surface  286 , as well as a pair of planar surfaces  288  extending longitudinally along a majority of the longitudinal length of the threaded post. In exemplary form, these planar surfaces  288  may be formed by planarizing opposing sides of the cylinder to remove material from the exterior, thereby decreasing the thickness of the cylinder at certain circumferential locations. In exemplary form, the material removed from the cylinder can be cross-sectionally represented as a first area outlined by a first chord extending between circumferential exterior points at zero degrees and ninety degrees and by the circumferential surface extending between the same points at zero degrees and ninety degrees. Similarly, the second area may be outlined by a second chord extending between one hundred eighty degrees and two hundred seventy degrees and by the circumferential surface extending between the same points at one hundred eighty degrees and two hundred seventy degrees. The planar surfaces  288 , in exemplary form, do not extend along the entire longitudinal length of the threaded post  284  so that a distal end  292  of the threaded post retains a cylindrical shape, while the opposing proximal end  294  of the threaded post is partially cylindrical. More specifically, a pair of cylindrical surfaces  296  extends between the planar surfaces  288  to partially define the exterior of the ratchet tube. Each cylindrical surface  296  is separated from the other cylindrical surface by approximately ninety rotational degrees, except for the distal end where the cylindrical surfaces seamlessly intersect with the cylindrical exterior surface  286 . Both cylindrical surfaces  296  are tapped along a predetermined length that extends to the proximal end  294  to provide a series of repeating, partial threads  298 . It is these partial threads  298  that are adapted to engage the tapped surfaces  276  of the nut  250  so that rotational repositioning of the nut results in longitudinal repositioning of the threaded post  284 . More specifically, clockwise rotation of the nut  250  may reposition the threaded post  284  longitudinally in a distal direction, while counter-clockwise rotation of the nut  250  may reposition the threaded post  284  longitudinally in a proximal direction, or vice versa. 
         [0055]    The distal end  292  of the threaded post  284  includes a cylindrical cavity that is tapped to provide internal threads  300 . These threads  300  are adapted to be engaged by the threads  304  of a post cap  306 . The post cap  306  includes a proximal cylindrical end  308  having threads  304  in order to mount the post cap to the threaded solid post  284 . A solid distal end  312  of the post cap  306 , integrally formed with the proximal end  308 , is also cylindrical and includes a larger diameter than the proximal end. This larger diameter is slightly less than the diameter of the cylindrical interior surface  122  of the ratchet tube  104 , thereby allowing the post cap to slide longitudinally within the interior of the ratchet tube. The distal end  312  also includes a circumferential trench  314  inset from the tip that is sized to accommodate a discontinuous friction sleeve  316 . The discontinuous friction sleeve  316  is seated within the trench  314  and partially compressed by the cylindrical interior surface  122  of the ratchet tube  104 . In a static environment, the outer diameter of the friction sleeve  316  is slightly larger than the diameter of the interior surface  122  of the ratchet tube  104 . But when the friction sleeve  316  is seated within the trench  314  and inserted into the ratchet tube  104 , the friction sleeve is circumferentially compressed to have an external diameter roughly equal to the diameter interior surface  122  of the ratchet tube. In this manner, the friction sleeve  316  creates frictional resistance against longitudinal repositioning of the sleeve with respect to the ratchet tube  104 , which also creates resistance against longitudinal repositioning of the post cap  306  and threaded post  284  with respect to the ratchet tube. But this frictional resistance is not so great as to inhibit longitudinal motion of the sleeve  316 , the post cap  306 , and threaded post  284  when the nut  250  is rotated. 
         [0056]    The proximal end  294  of the threaded post  284  is mounted to a ball joint  320  having a spherical ball end  322  integrally formed with a hollow cylinder  324 . The hollow cylinder is threaded and these threads  328  are adapted to engage the partial threads  298  of the threaded post  284  in order to mount the threaded post to the ball joint  320 . 
         [0057]    The spherical ball end  322  of the ball joint  320  is rotationally and pivotally repositionable with respect to a socket cooperatively formed by a ball joint housing  330  and a ball joint cap  334 . In exemplary form, the ball joint housing  330  comprises a casing that partially encapsulates the spherical ball end  322  of the ball joint  320 . On the interior of this casing is a semispherical depression that provides a bearing surface against which the spherical ball end rotates and pivots. The ball joint housing  330  also includes a circular ring  336  integrally formed with the casing and having a diameter greater than the diameter of the spherical ball end. In order to retain the spherical ball end  322  within the ball joint housing  330 , as well as selectively removing the spherical ball end from within the ball joint housing, the circular ring includes threads  340  that are adapted to engage threads  342  of the ball joint cap  334  to secure the ball joint cap to the ball joint housing via a friction fit. 
         [0058]    As shown in  FIG. 16 , the ball joint cap  334  is ring-shaped and includes a central opening defined by an arcuate circumferential surface  344 . This arcuate circumferential surface  344  cooperates with the semispherical depression of the ball joint housing  330  to create the spherical socket within which the spherical ball end  322  is able to rotate and pivot. In this exemplary embodiment, the diameter of the central opening of the ball joint cap  334  is less than the diameter of the spherical ball end  322  within the ball joint housing  330  so that once the ball joint cap and ball joint housing are mounted to one another with the spherical ball end  322  located therein, removal of the spherical ball end is not possible without discontinuing the ball joint cap from being mounted to ball joint housing. 
         [0059]    Referring back to  FIGS. 5-7 , as discussed previously, the distal end of the ratchet box  102  includes a distal opening  156  defined by the second cylindrical interior wall  160 , which ends proximally when it meets the distal flange  162 . The distal opening is sized to accommodate throughput of the ratchet tube  104  as well as partial insertion of another tube  350 . This second tube  350  is longitudinally cylindrical and includes a smooth exterior circumferential surface  352  that has a relatively constant diameter along the vast majority of the length of the second tube, but for the distal end  356 . An interior of the second tube  350  is hollow and includes an opening  358  at a proximal end  360  of the second tube. This opening  358  provides access to a cylindrical cavity partially defined by interior circumferential wall  362  having a diameter large enough to accommodate the ratchet tube  104 . In exemplary form, the proximal end  360  of the second tube  350  is inserted through the distal opening  156  of the ratchet box  102  and longitudinally repositioned until the proximal end  360  contacts the distal flange  162  on the inside of the ratchet box. It should be noted that the internal diameter of the second cylindrical interior wall  160  of the ratchet box  102  is slightly less than the external diameter of the second tube  350 , thereby securing the second tube to the ratchet box via a friction fit. 
         [0060]    The longitudinal profile of the second tube  350  is substantially constant until it changes when approximately reaching the distal end  356 . Proximate the distal end  356 , the interior circumferential wall  362  terminates at an internal, ring-shaped flange  366  operative to change the cross-section of the cavity. In particular, the flange  360  includes a central opening that feeds into a cylindrical cavity having a diameter less than that of the interior circumferential wall  362 . This smaller diameter cylindrical cavity is partially defined by a threaded circumferential surface  370  that is adapted to engage a threaded circumferential surface  374  of a second ball joint  380 . In contrast to the first ball joint  320  (see  FIG. 2 ) that includes a female connection comprising a hollow cylinder having an internal circumferential surface  328  that is threaded, this second ball joint  380  include a male connection comprising an external circumferential surface  374  threaded to fit within and engage the threaded circumferential surface  370  of the smaller diameter cylindrical cavity of the second tube  350 . 
         [0061]    The second ball joint  380  comprises a spherical ball end  382  integrally formed with the male connection. This spherical ball end  382  of the ball joint  380  is rotationally and pivotally repositionable with respect to a socket cooperatively formed by a ball joint housing  390  and a ball joint cap  394 . In exemplary form, the ball joint housing  390  comprises a casing that partially encapsulates the spherical ball end  382  of the ball joint  380 . On the interior of this casing is a semispherical depression that provides a bearing surface against which the spherical ball end  382  rotates and pivots. The ball joint housing  390  also includes a circular ring  396  integrally formed with the casing and having a diameter greater than the diameter of the spherical ball end  382 . In order to retain the spherical ball end  382  within the ball joint housing  390 , as well as selectively removing the spherical ball end from within the ball joint housing, the circular ring includes threads  400  that are adapted to engage threads  402  of the ball joint cap  394  to secure the ball joint cap to the ball joint housing. 
         [0062]    As shown in  FIG. 17 , the ball joint cap  394  is ring-shaped and includes a central opening defined by an arcuate circumferential surface  404 . This arcuate circumferential surface  404  cooperates with the semispherical depression of the ball joint housing  390  to create the spherical socket within which the spherical ball end  382  is able to rotate and pivot. In this exemplary embodiment, the diameter of the central opening of the ball joint cap  394  is less than the diameter of the spherical ball end  382  within the ball joint housing  390  so that once the ball joint cap and ball joint housing are mounted to one another with the spherical ball end  382  located therein, removal of the spherical ball end is not possible without discontinuing the ball joint cap from being mounted to ball joint housing. 
         [0063]    Referencing  FIGS. 18-28 , a second exemplary ratcheting strut  500  makes use of several component parts of the first exemplary ratcheting strut  100 . For example, the second ratcheting strut  500  uses the same tube mount  220 , the threaded post  284 , the post cap  306 , the friction sleeve  316 , the ball joint  320 , the second tube  350 , and the ball joint  380 . Accordingly, a detailed description of these components has been omitted as part of discussing the second exemplary ratcheting strut  500  to omit redundancy, thereby furthering brevity. 
         [0064]    This second exemplary ratcheting strut  500  includes a ratchet box  502  having a longitudinal opening extending therethrough that accommodates throughput of a ratchet tube  504 . In exemplary form, the longitudinal opening is partially defined by a pair of arcuate interior walls  506  (partial cylindrical) circumferentially interposed a pair of planar walls  508 . The planar walls  508  are parallel to one another and spaced apart from one another a first predetermined distance that is less than a distance (in effect, the diameter of a cylinder the arcuate walls would be a part of) the arcuate walls  506  are spaced apart from one another. In this fashion, the planar walls  508  operate to narrow the vertical cross-section in comparison to a hollow cylindrical cavity. Working together, the arcuate walls  506  and the planar walls  508  allow longitudinal traversal of the ratchet tube  504 , while inhibiting axial rotation of the ratchet tube. 
         [0065]    In this exemplary embodiment, the ratchet tube  504  comprises a cylindrical ring body having a cylindrical exterior surface  520  axially outset from a cylindrical interior surface  522 . In this manner, the interior of the ratchet tube  504  is hollow and has a constant vertical, circular cross-section along its longitudinal length. An exterior surface of the ratchet tube  504  includes the cylindrical exterior surface  520 , as well as a pair of planar surfaces  524  extending longitudinally along a majority of the longitudinal length of the ratchet tube. In exemplary form, these planar surfaces  524  may be formed by planarizing opposing sides of the ring body (i.e., hollow cylindrical tube) to remove material from the outside of the ring body, thereby decreasing the wall thickness of the ring body, but not impacting the dimensions of the cylindrical interior surface  522 . In exemplary form, the material removed from the ring body can be cross-sectionally represented as a first area outlined by a first chord extending between circumferential exterior points at zero degrees and ninety degrees and by the circumferential surface extending between the same points at zero degrees and ninety degrees. Similarly, the second area may be outlined by a second chord extending between one hundred eighty degrees and two hundred seventy degrees and by the circumferential surface extending between the same points at one hundred eighty degrees and two hundred seventy degrees. The planar surfaces  524 , in exemplary form, do not extend along the entire longitudinal length of the ratchet tube  504  so that a distal end  526  of the ratchet tube is cylindrical, while the opposing proximal end  528  of the ratchet tube is partially cylindrical. More specifically, a pair of arcuate surfaces  532 ,  534  extends between the planar surfaces  524  to partially define the exterior of the ratchet tube. Each arcuate surface  532 ,  534  is separated from the other cylindrical surface by approximately ninety rotational degrees, except for the distal end where the arcuate surfaces seamlessly intersect with the cylindrical exterior surface  520 . Both the dorsal and ventral arcuate surfaces  532  include a series of angled depressions  536  that are longitudinally repeated and consistently spaced apart from one another, thereby resulting in a series of angled teeth  538  that are longitudinally inset from the distal and proximal ends  526 ,  528  of the ratchet tube  504 . In exemplary form, each tooth  538  includes a vertical surface  544  and an inclined surface  546  that intersects the vertical surface to form a horizontal peak  548 . As will be discussed in more detail hereafter, the angled nature of the inclined surfaces  546  cooperate with corresponding surfaces of a pair of repositionable levers  570 A,  570 B to allow ratcheting action between the levers and the ratchet tube  504 . 
         [0066]    The shape of the ratchet tube  504  allows it to be inserted into the longitudinal opening of the ratchet box  502  so that the proximal end  528  of the ratchet tube is inserted into a distal opening  554  of the ratchet box  502  and extends through a proximal opening  556  prior to insertion of the distal end  526  into the interior of the ratchet box. The distal opening  554  is defined by a cylindrical interior wall  560  having a diameter larger than the arcuate interior walls  506 . This cylindrical interior wall  560  extends proximally until terminating at a distal flange  562  that extends between the cylindrical interior wall and the arcuate interior walls  506 . It should be noted that the cylindrical interior wall  560  and the arcuate interior walls  506  are coaxial with one another. 
         [0067]    In this exemplary embodiment, the distal flange  560  is operative to inhibit throughput of objects having a cross-sectional distance larger than the distance between the planar walls  508 . As mentioned previously, the distal end  526  of the ratchet tube  504  is cylindrical and exhibits a constant exterior diameter, whereas the proximal end  528  and a majority of the longitudinal length of the ratchet tube exhibits a cross-section that is partially circular with respect to the arcuate surfaces  532 ,  534 , but is partially rectangular with respect to the planar surfaces  524 . This dual shape (circular and rectangular) profile is also consistent with the dual shape profile on the interior walls  506 ,  508  of the ratchet box  102 . In exemplary form, the exterior diameter (between the arcuate surfaces  532 ,  534 ) of the ratchet tube  504  is slightly less than the internal diameter of the arcuate interior walls  506 . Likewise, the horizontal width between the planar surfaces  508  is slightly larger than the horizontal distance between the planar surfaces  524 . As a result, the proximal end  528  of the ratchet tube  504  is able to be longitudinally repositioned along the entire length of the longitudinal opening of the ratchet box  502 , whereas the distal end  526  of the ratchet tube is able to be longitudinally repositioned within only a portion of the longitudinal opening because the distal end cannot pass beyond the distal flange  562 . In this manner, when the proximal end  528  of the ratchet tube  504  is first inserted into the distal opening  554  of the ratchet box  502  and longitudinally repositioned proximally, eventually the distal end  526  of the ratchet tube (where the planar surfaces  524  terminate and the uniform circumferential surface begins) abuts the distal flange  562 , which prohibit further proximal motion of the ratchet tube. 
         [0068]    In order to fix the position of the ratchet tube  504  with respect to the ratchet box  502 , two levers  570 A,  57013  are repositionably mounted to the ratchet box to selectively engage the ratchet tube. More specifically, each lever  570 A,  570 B comprises an L-shaped beam  572  having a cylindrical pivot orifice  574  that accepts a dowel  576  concurrently seated within a respective cylindrical dowel orifice  578  in order to mount the ratchet box  502  to the lever. In exemplary form, each dowel  576  is cylindrical and has an external diameter that is slightly larger than the internal diameter of the corresponding cylindrical dowel orifice  578 , thus securing the dowel in position via a friction fit. In contrast, the diameter of the corresponding cylindrical pivot orifice  574  is slightly larger than the external diameter of the respective dowel  576 , thereby allowing pivoting motion of the lever  570 A,  570 B around the dowel. 
         [0069]    In this exemplary embodiment, each lever  570 A,  570 B is biased by a spring  580  to engage the ratchet tube  504 . More specifically, the coil spring  580  is seated within a respective spring receiver  582  of the ratchet box  502 . Each spring receiver  582  comprises a ring-shaped depression that circumscribes a cylindrical projection that is adapted to be partially inserted into one end of the coil spring  580 . Similarly, the underside of the lever  570 S,  570 B also includes a spring receiver  584  that likewise comprises a ring-shaped depression that circumscribes a cylindrical projection adapted to be partially inserted into the other end of the coil spring  580 . The bias of the coil spring  580  is selected or set so that when no affirmative pressure is applied by a user to the lever  570 A,  570 B, a head  588  of the lever contacts the ratchet tube  504 . In exemplary form, the head  588  of each lever  570 A,  570 B includes a series of angled teeth  592  that are each formed by the interaction of a vertical surface  594  and an inclined surface  596  that intersects the proximal surface to form a horizontal peak  598 . In this fashion, the angled teeth  592  of each lever  570 A,  570 B are inclined to match the incline of the angled teeth  538  of the ratchet tube  504  nearest to each lever. As a result, when no affirmative pressure is applied by a user to the lever  570 A, the ratchet tube  504  may not be repositioned proximally because the other lever  570 B inhibits travel as the vertical surfaces  594  of the lever  570 B teeth  592  contact the vertical surfaces  544  of the ratchet tube  504  lower teeth  538 . Likewise, when no affirmative pressure is applied by a user to the lever  57013 , the ratchet tube  504  may not be repositioned distally because the other lever  570 A inhibits travel as the vertical surfaces  594  of the lever  570 A teeth  592  contact the vertical surfaces  544  of the ratchet tube  504  upper teeth  538 . As a result, in order to reposition the ratchet tube  504  proximally, a user needs to apply an affirmative pressure to the lever  57013  to overcome the spring bias of the spring  580  and vertically separate the vertical surfaces  594  of the lever  570 B teeth  592  with the vertical surfaces  544  of the ratchet tube  504  lower teeth  538 . It does not matter that the other lever  570 A continues to engage the ratchet tube  504  because the inclined surfaces  596  of the teeth  592  of the other lever  570 A are engaging the inclined surfaces  546  of the upper teeth  538 , thereby allowing the inclined surfaces  546 ,  596  to slide against one another so that the ratchet tube  504  may be repositioned proximally. When the appropriate proximal travel is reached, the user simply discontinues affirmative pressure to the lever  570 B, thereby allowing the spring  580  bias to dominate and cause the lever  570 B to contact the ratchet tube  504  so that the vertical surfaces  144 ,  194  contact one another and do not allow proximal motion. Conversely, in order to reposition the ratchet tube  504  distally, a user needs to apply an affirmative pressure to the lever  570 A to overcome the spring bias of the spring  580  and vertically separate the vertical surfaces  594  of the lever  570 A teeth  592  with the vertical surfaces  544  of the ratchet tube  504  upper teeth  538 . It does not matter that the other lever  570 B continues to engage the ratchet tube  504  because the inclined surfaces  596  of the teeth  592  of the other lever  570 B are engaging the inclined surfaces  546  of the lower teeth  538 , thereby allowing the inclined surfaces  546 ,  596  to slide against one another so that the ratchet tube  504  may be repositioned distally. When the appropriate distal travel is reached, the user simply discontinues affirmative pressure to the lever  570 A, thereby allowing the spring  580  bias to dominate and cause the lever  570 A to contact the ratchet tube  504  so that the vertical surfaces  144 ,  194  contact one another and do not allow distal motion. 
         [0070]    Each lever  570 A,  570 B may also be locked in position so that the teeth  592  engage the angled teeth  538  of the ratchet tube  504 . In order to lock either lever  570 A,  570 B in an engaged position with the ratchet tube  504 , the lever includes a lock orifice  600  that is sized to receive a portion of a thumb screw  204 . The thumb screw  204  includes a knob  206  mounted to a perpendicularly extending, linear projection  208  having threads  210  adapted to engage threads (not shown) on the inside of a thumb screw orifice  614  extending through the ratchet box  102 . When the projection  208  of the thumb screw  204  is inserted through the thumb screw orifice  614  and lock orifice  600  for a respective lever, the lever  570 A,  570 B is not pivotally repositionable so that the teeth  592  of the lever are out of the line of travel of the teeth  538  of the ratchet tube  504 . Consequently, to pivot either lever  570 A,  570 B so that the teeth  592  of the lever are out of the line of travel of the teeth  538  of the ratchet tube  504 , the thumb screw  204  needs to be positioned so that the projection  208  is no longer received within the lock orifice  600 . After the thumb screw  204  is positioned so that the projection  208  is no longer received within the lock orifice  600 , the lever  570 A,  570 B may be repositioned by application of affirmative pressure to overcome the bias of the spring  580 , thereby pivoting the lever so that the teeth  592  of the lever are out of the line of travel of the teeth  538  of the ratchet tube  504 . 
         [0071]    When the ratchet tube  504  is repositioned with respect to the ratchet box  502 , other components mounted to the ratchet tube are also repositioned. In this exemplary embodiment, a tube mount  220  is coupled to the proximal end  528  of the ratchet tube via a friction fit. A nut  650  is mounted to the tube mount  220  and is rotationally repositionable with respect thereto. The nut  650  includes one or more through set screw orifices  652  that extend from an exterior surface  654  into a hollow interior  658 , which includes proximal and distal openings  660 ,  662 . The exterior surface  654  comprises a hexagonal pattern of six alternating arcuate troughs  656  and six arcuate projections  658  that provide grip for a user to grasp the nut  650  and facilitate rotation of the nut with respect to the sleeve  236  of the tube mount  220 . In this exemplary embodiment, the distal opening  662  allows access to a cylindrical cavity defined by a circumferential interior wall  670 . At the proximal end of this interior wall  678  is a flange  672  that provides an abutment surface against which the exposed proximal end of the sleeve  236  contacts when fully seated within the nut  650 . The flange  672  also operates to decrease the diameter of the hollow interior  658  and abuts a cylindrical interior surface  674  having threads  676  adapted to be engaged by the threads  298  of the threaded post  284  that extends through the nut  650 , the tube mount  220 , and partially through an interior of the ratchet tube  504 . It is these partial threads  298  that are adapted to engage the threads  676  of the nut  650  so that rotational repositioning of the nut results in longitudinal repositioning of the threaded post  284 . More specifically, clockwise rotation of the nut  650  may reposition the threaded post  284  longitudinally in a distal direction, while clockwise rotation of the nut  650  may reposition the threaded post  284  longitudinally in a proximal direction, or vice versa. 
         [0072]    As with the first exemplary ratcheting strut  100 , this second exemplary ratcheting strut  500  includes a ball joint  320  mounted to the threaded post  284 . Similarly, this second exemplary ratcheting strut  500  also includes a second tube  350  mounted to the ratchet box  502  and a ball joint  380  mounted to the second tube. For purposes of illustration only with respect to this second exemplary ratcheting strut  500 , the ball joint housing and ball joint cap for each ball joint  320 ,  380  have been omitted. Nevertheless, it is to be understood that the second exemplary ratcheting strut  500  includes a ball joint housing and a ball joint cap for each ball joint  320 ,  380 . 
         [0073]    Referencing  FIGS. 29-34 , a third exemplary ratcheting strut  700  makes use of several component parts of the first exemplary ratcheting strut  100 . For example, the third ratcheting strut  700  uses the same ratchet tube  104 , repositionable lever  170 , tube mount  220 , nut  250 , post cap  306 , friction sleeve  316 , ball joint  320 , ball joint housings  330 ,  390 , ball joint caps  334 ,  394 , second tube  350 , and ball joint  380 . Accordingly, a detailed description of these components has been omitted as part of discussing the third exemplary ratcheting strut  700  to omit redundancy, thereby furthering brevity. Essentially, the third exemplary ratcheting strut  700  differs from the first exemplary ratcheting strut  100  by the ratchet box  702  and threaded post  704 . 
         [0074]    This third exemplary ratcheting strut  700  includes a ratchet box  702  having a longitudinal opening extending therethrough that accommodates throughput of a ratchet tube  104 . In exemplary form, the longitudinal opening is partially defined by a pair of arcuate interior walls  706  (partial cylindrical) circumferentially interposed a pair of planar walls  708 . The planar walls  708  are parallel to one another and spaced apart from one another a first predetermined distance that is less than a distance (in effect, the diameter of a cylinder the arcuate walls would be a part of) the arcuate walls  706  are spaced apart from one another. In this fashion, the planar walls  708  operate to narrow the vertical cross-section in comparison to a hollow cylindrical cavity. Working together, the arcuate walls  706  and the planar walls  708  allow longitudinal traversal of the ratchet tube  104 , while inhibiting axial rotation of the ratchet tube. 
         [0075]    The shape of the ratchet tube  104  allows it to be inserted into the longitudinal opening of the ratchet box  702  so that the proximal end  128  of the ratchet tube is inserted into a distal opening  712  of the ratchet box  702  and extends through aproximal opening  714  prior to insertion of the distal end  126  into the interior of the ratchet box. 
         [0076]    In this exemplary embodiment, the dimensions of the distal and proximal openings  712 ,  714  are operative to inhibit complete throughput of objects having a cross-sectional distance larger than the distance between the planar walls  708 . Because the distal end  126  of the ratchet tube  104  is cylindrical and exhibits a constant exterior diameter, whereas the proximal end  128  and a majority of the longitudinal length of the ratchet tube exhibits a cross-section that is partially circular with respect to the arcuate surfaces  132 ,  134 , but is partially rectangular with respect to the planar surfaces  124 . This dual shape (circular and rectangular) profile is also consistent with the dual shape profile on the interior walls  706 ,  708  of the ratchet box  702 . In exemplary form, the exterior diameter (between the arcuate surfaces  132 ,  134 ) of the ratchet tube  104  is slightly less than the internal diameter of the arcuate interior walls  706 . Likewise, the horizontal width between the planar surfaces  708  is slightly larger than the horizontal distance between the planar surfaces  124 . As a result, the proximal end  128  of the ratchet tube  104  is able to be longitudinally repositioned along the entire length of the longitudinal opening of the ratchet box  702 , whereas the distal end  126  of the ratchet tube is able to be longitudinally repositioned within only a portion of the longitudinal opening because the distal end cannot pass into the interior of the ratchet box. In this manner, when the proximal end  128  of the ratchet tube  104  is first inserted into the distal opening  712  of the ratchet box  702  and longitudinally repositioned proximally, eventually the distal end  126  of the ratchet tube (where the planar surfaces  124  terminate and the uniform circumferential surface begins) abuts the outside of the ratchet box, which prohibits further proximal motion of the ratchet tube. 
         [0077]    In order to fix the position of the ratchet tube  104  with respect to the ratchet box  702 , a lever  170  is repositionably mounted to the ratchet box to selectively engage the ratchet tube. Reference is had to the previous discussion of how the ratchet tube  104  and  170  interact to allow or retard repositioning of the ratchet tube. 
         [0078]    When the ratchet tube  104  is repositioned with respect to the ratchet box  702 , other components mounted to the ratchet tube are also repositioned. In this exemplary embodiment, a tube mount  220  is coupled to the proximal end  128  of the ratchet tube via a friction fit. A nut  250  is mounted to the tube mount  220  and is rotationally repositionable with respect thereto. The nut  250  includes threads  276  that engage threads  718  of the threaded post  704  while the threaded post extends through the nut, the tube mount  220 , and partially through an interior of the ratchet tube  104 . It is these threads  718  that are adapted to engage the threads  276  of the nut  250  so that rotational repositioning of the nut results in longitudinal repositioning of the threaded post  704 . 
         [0079]    In exemplary form, the threaded post  704  comprises a hybrid exterior surface comprising a pair of arcuate surfaces  720  that are interposed by a pair of planar surfaces  722  extending longitudinally along the longitudinal length of the threaded post. In exemplary form, these planar surfaces  722  may be formed by planarizing opposing sides of a cylinder to remove material from the exterior, thereby decreasing the thickness of the cylinder at certain circumferential locations. In exemplary form, the material removed from the cylinder can be cross-sectionally represented as a first area outlined by a first chord extending between circumferential exterior points at zero degrees and ninety degrees and by the circumferential surface extending between the same points at zero degrees and ninety degrees. Similarly, the second area may be outlined by a second chord extending between one hundred eighty degrees and two hundred seventy degrees and by the circumferential surface extending between the same points at one hundred eighty degrees and two hundred seventy degrees. Both arcuate surfaces  720  are tapped to provide a series of repeating threads  718 . It is these threads  718  that are adapted to engage the tapped surfaces  276  of the nut  250  so that rotational repositioning of the nut results in longitudinal repositioning of the threaded post  704 . More specifically, clockwise rotation of the nut  250  may reposition the threaded post  704  longitudinally in a distal direction, while clockwise rotation of the nut  250  may reposition the threaded post  704  longitudinally in a proximal direction, or vice versa. 
         [0080]    A distal end  724  of the threaded post  704  includes a cylindrical cavity that is tapped to provide internal threads  726 . These threads  726  are adapted to be engaged by the threads  304  of the post cap  306 , which is mounted to the friction sleeve  316 . As discussed previously, the diameter of the cylindrical interior surface  122  of the ratchet tube  104  is slightly less than the exterior diameter of the friction sleeve  316 , thereby allowing the post cap and friction sleeve to slide longitudinally within the interior of the ratchet tube, but with a predetermined resistance. But this frictional resistance is not so great as to inhibit longitudinal motion of the sleeve  316 , the post cap  306 , and threaded post  704  when the nut  250  is rotated. 
         [0081]    A proximal end  730  of the threaded post  704  is mounted to a ball joint  320  having a spherical ball end  322  integrally formed with a hollow cylinder  324 . The hollow cylinder is threaded and these threads  328  are adapted to engage the threads  718  of the threaded post  704  in order to mount the threaded post to the ball joint  320  via a friction fit. Similar to the first exemplary ratcheting strut  100 , this third ratcheting strut also includes a ball joint housing  330  and a ball joint cap  334 . 
         [0082]    Referring back to  FIGS. 32 and 33 , the ratchet box  702  includes a cylindrical cavity  732  that extends in parallel to, but is offset from, the longitudinal opening. This cylindrical cavity is adapted to receive a portion of the second tube  250  and is bounded by a cylindrical interior wall  734  that abuts a circular, planar wall  736 . In exemplary form, the diameter of the cylindrical interior wall  734  is slightly less than the exterior diameter of the second tube  250 , thereby mounting the ratchet box  702  to the second tube once an end of the second tube is inserted deep enough to abut the planar wall. 
         [0083]    As with the first exemplary ratcheting strut  100 , the second tube  250  of the third exemplary ratcheting strut  700  is mounted to a ball joint  380  that includes a male connection comprising an external circumferential surface  374  threaded to fit within and engage the threaded circumferential surface  370  of the smaller diameter cylindrical cavity of the second tube  350 . Likewise, this third ratcheting strut  700  also includes a ball joint housing  330  and a ball joint cap  334 . 
         [0084]    Unlike the previous two exemplary ratcheting struts  100 ,  500  that included ratcheting structures that were coaxial with the second tube  350 , this third exemplary ratcheting strut  700  has the ratcheting structures axially offset, but in parallel with, the second tube. This offset orientation has the advantages of allowing more adjustable length, allowing use of solid bodies, easier manufacture, and increased strength. 
         [0085]    Following from the above description and invention summaries, it should be apparent to those of ordinary skill in the art that, while the methods and apparatuses herein described constitute exemplary embodiments of the present invention, the invention is not limited to the foregoing and changes may be made to such embodiments without departing from the scope of the invention as defined by the claims. Additionally, it is to be understood that the invention is defined by the claims and it is not intended that any limitations or elements describing the exemplary embodiments set forth herein are to be incorporated into the interpretation of any claim element unless such limitation or element is explicitly stated. Likewise, it is to be understood that it is not necessary to meet any or all of the identified advantages or objects of the invention disclosed herein in order to fall within the scope of any claims, since the invention is defined by the claims and since inherent and/or unforeseen advantages of the present invention may exist even though they may not have been explicitly discussed herein.