Abstract:
The disclosed device solves the problem of fixation of a fractured humerus, or other long bone, by allowing a surgeon to first fix the proximal end of the implant and set the fracture, followed by fixation of the distal end without the use of screws.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The application is a continuation-in-part of U.S. application Ser. No. 13/445,954 for Intramedullary Nail System with Tang Fixation filed Apr. 13, 2012. 
    
    
     FIELD 
     The present invention relates to an intramedullary system for coupling a first and second portion of bone across a fracture. 
     BACKGROUND 
     Intramedullary nails were first used in the 1930s. These early nails were inserted into the intramedullary canal of the bone. The result was immediate fixation of fractures, reduction in patient recovery time, increased mobility, and improved quality of life. Multiple examples of such nails are present in the prior art. 
     But rotation of the inserted nails was a problem. Rotation would result in the nail being in a position different than that chosen by the surgeon. To address this issue, screws were installed that held plates against the outer surface of the bone, used to fix the rotational position of the bone. The plates changed the profile of the bone, potentially causing irritation to surrounding tissue. 
     The most significant problem caused by the requirement of additional screws is the additional time required under exposure to x-ray radiation. The installation of each screw requires additional x-rays to verify location, depth, and so forth. X-ray radiation is damaging to the patient, but is especially troublesome to the surgeon because each surgeon must perform many of these surgeries. Thus, any reduction in x-rays is highly beneficial. 
     SUMMARY 
     The disclosed device solves the problem of fixation of a fractured humerus, or other long bone, by allowing a surgeon to first fix the proximal end of the implant and set the fracture, followed by fixation of the distal end without the use of screws. 
     The humeral nail solves practical problems encountered during surgery to correct a fracture of the humerus. The two particular problems are: 1) the proximity of nerves to the distal portion of the humerus, near the elbow, and 2) the need to affix the implant on the proximal end, near the shoulder, before affixing the implant on the distal end, near the elbow. 
     Put simply, the humeral nail is implanted through a penetration in the proximal end of the humerus, passing through one or more fracture lines. It is affixed to the bone on the proximal end by screws, and the distal end by extending tangs, or anchors, that interface with the internal surface of the humerus. 
     The use of tangs avoids the first problem of damage to nerves in close proximity to the surface of the distal portion of the humerus, avoiding the need for distal screws. By affixing the humeral nail to the interior of the humerus, there is no worry of distally installed screws damaging nerves. 
     The second problem requires further explanation. When the humerus is fractured it is common for the now-separate pieces of bone to become displaced and misaligned. These separate pieces must be restored to their original positions. This process is known as “reduction.” 
     The surgeon must perform the reduction in conjunction with positioning of the humeral nail because the orientation of the locking screws is important, as is the depth of humeral nail placement. A humeral nail that is too depressed, or placed too deeply within the humerus, may result in locking screw penetrations that are misplaced. A humeral nail that is too prominent, or protruding beyond the head of the humerus, may result in soft tissue damage. 
     And thus is the problem. The distal tangs must be extended after the locking screws are installed, but the locking screws cross the center of the humeral nail and take up space in the hollow interior cavity of the humeral nail, making access to the distal tangs difficult. The solution is a mechanism that surrounds the installed locking screws, allowing actuation of the distal tangs from the proximal end. As an added benefit, the mechanism acts to secure the locking screws in place, preventing any unscrewing. If upward extending tangs are used, the actuation of the tangs also compresses the fracture. This compression strengthens the bone to allow use of the arm, and encourages healing by minimizing the amount of required bone growth. 
     Description of the surgical technique is useful to understand many of the unique features present in the disclosed device. The technique described below will be directed at implantation into a human humerus, but a similar technique is employed for other uses. 
     First, the patient needs to be positioned. The patient is placed in a semi-recumbent “beach chair” position on a radiolucent table. The affected arm is secured to an adjustable side table or arm rest. This position provides a clear view for radiography of the affected arm. The head of the humerus can now be exposed. 
     An anterolateral approach is performed by starting an incision at the anterolateral tip of the acromion and extending the incision distally over the deltoid muscle. The deltoid muscle is split along its fibers and retracted to expose the supraspinatus muscle and tendon. The supraspinatus tendon is incised in line with its fibers. 
     Next, the starting point for implantation needs to be determined. The entry point is located at the apex of the humeral head, in line with the medullary canal, or marrow cavity. 
     Next, an awl or trocar tip guide wire is used to create a hole in the humerus. The location and trajectory are confirmed radiographically using at least two orthogonal images. If a guide wire is used to gain entry into the humerus, a cannulated drill connected to a power driver is passed over the wire and through a tissue protection sleeve. The drill is used to enlarge the hole and allow passage of the implant. 
     Next, the trocar tip guide wire is exchanged for a ball tip guide wire by way of a flexible exchange tube. If the awl was used to gain entry in the humerus, the ball tip guide wire is passed through its cannulation and down the medullary canal. A ball tip guide wire is necessary for reaming, or enlarging, the medullary canal to accommodate the implant. 
     Prior to reaming, the humeral nail length must be determined. To provide support the humeral nail must pass the fracture line. Additionally, the distal end of the humeral nail, where the nail tangs are located, must be placed in an area of bone that will allow extension of the nail tangs into the cortex, or dense shell, of the bone. To determine the appropriate humeral nail length, a metal guide, which is visible on an x-ray image, is held over the bone to compare the bone width to the required width shown by the metal guide. The metal guide in combination with a guide wire ruler is used to determine the ideal humeral nail length. 
     Next, a flexible reamer is passed over the guide wire, enlarging the diameter of the medullary canal to accommodate the distal portion of the humeral nail. After the canal has been reamed to the appropriate diameter, the ball tip guide wire is exchanged for a smooth guide wire. 
     Next, the nail is slid over the guide wire and inserted into the humeral canal. Insertion can be aided by gentle twisting, constant pressure, or striking with a slap hammer. The guide wire is removed once the humeral nail in fully inserted. 
     Next, the appropriate version, or rotational alignment, of the humeral nail must be set. This is done using the guide arm, with the patient&#39;s forearm serving as a reference. After the version is set, the nail is in its final position. 
     Next, the proximal locking screws are positioned. Using the guide assembly, a tissue protection sleeve and internal drill sleeve are inserted through an incision in the skin and advanced to the level of the bone. The drill is used to create a hole into the humeral head until the subchondral bone is reached. A measurement is taken from the head of the drill to determine the length of the screw needed at that position. The drill and drill sleeve are removed and the corresponding screw is inserted. This step is repeated for the remaining screw holes, as dictated by the fracture pattern. 
     Next, the nail tangs are extended. A deployment driver is inserted into the proximal end of the nail, threading into the linear tang actuator. The nail deployment driver is rotated, in turn rotating the actuation screw. The interaction of the first and second actuation threads causes the linear actuator to move axially with respect to the actuator screw. 
     This in turn causes the tips of the nail tangs to extend beyond the nail portals. The nail tangs will begin to extend through the spongy cancellous bone. The surgeon must monitor the force, taking care to stop the extension of the tangs when the resistance increases sharply, indicating contact with dense cortical bone. Alternatively, the appropriate extension is determined using a torque limiter in conjunction with the nail deployment driver. Ceasing extension of the tangs prior to full deployment is permissible because full deployment is not necessary to affix the nail to the bone. 
     Finally, the tools used for installation can be removed, and the proximal nail end cap installed to prevent tissue growth over the proximal end of the nail. While the nail is suited for permanent installation, if needed, the procedure is fully reversible. The nail tangs can be retracted and all parts removed. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention can be best understood by those having ordinary skill in the art by reference to the following detailed description when considered in conjunction with the accompanying drawings in which: 
         FIG. 1  illustrates a first view of a first embodiment of the humeral nail. 
         FIG. 2  illustrates a second view of a first embodiment of the humeral nail. 
         FIG. 3  illustrates an exploded view a first embodiment of the humeral nail. 
         FIG. 4  illustrates a cross-sectional and exploded view of a first embodiment of the humeral nail. 
         FIG. 5  illustrates a first view of the proximal portion of the humeral nail in a non-actuated position. 
         FIG. 6  illustrates a second view of the proximal portion of the humeral nail in a non-actuated position. 
         FIG. 7  illustrates a first view of the proximal portion of the humeral nail in an actuated position. 
         FIG. 8  illustrates a second view of the proximal portion of the humeral nail in an actuated position. 
         FIG. 9  illustrates a first interior view of the linear tang actuator portion of the humeral nail in a non-actuated position. 
         FIG. 10  illustrates a second interior, cross-sectional view of the linear tang actuator portion of the humeral nail in a non-actuated position. 
         FIG. 11  illustrates a first interior view of the linear tang actuator portion of the humeral nail in an actuated position. 
         FIG. 12  illustrates a second interior, cross-sectional view of the linear tang actuator portion of the humeral nail in an actuated position. 
         FIG. 13  illustrates an interior, cross-sectional view of a first embodiment of the humeral nail in a non-actuated position. 
         FIG. 14  illustrates a second interior, cross-sectional view of a first embodiment of the humeral nail in a non-actuated position. 
         FIG. 15  illustrates a third interior, cross-sectional view of a first embodiment of the humeral nail in a non-actuated position. 
         FIG. 16  illustrates an interior, cross-sectional view of a first embodiment of the humeral nail in an actuated position. 
         FIG. 17  illustrates a second interior, cross-sectional view of a first embodiment of the humeral nail in an actuated position. 
         FIG. 18  illustrates a third interior, cross-sectional view of a first embodiment of the humeral nail in an actuated position. 
         FIG. 19  illustrates an isometric view of a first embodiment of the linear tang actuator of the humeral nail. 
         FIG. 20  illustrates a front view of a first embodiment of the linear tang actuator of the humeral nail. 
         FIG. 21  illustrates a back view of a first embodiment of the linear tang actuator of the humeral nail. 
         FIG. 22  illustrates a right view of a first embodiment of the linear tang actuator of the humeral nail. 
         FIG. 23  illustrates a left view of a first embodiment of the linear tang actuator of the humeral nail. 
         FIG. 24  illustrates a top view of a first embodiment of the linear tang actuator of the humeral nail. 
         FIG. 25  illustrates a bottom view of a first embodiment of the linear tang actuator of the humeral nail. 
         FIG. 26  illustrates a cross-sectional view of a first embodiment of the linear tang actuator of the humeral nail. 
         FIG. 27  illustrates a partial-cross-sectional view of the distal portion of a first embodiment of the humeral nail in a non-actuated position. 
         FIG. 28  illustrates a partial-cross-sectional view of the distal portion of a first embodiment of the humeral nail in an actuated position. 
         FIG. 29  illustrates a bottom view of a first embodiment of the humeral nail in a non-actuated position. 
         FIG. 30  illustrates a top view of a first embodiment of the humeral nail in a non-actuated position. 
         FIG. 31  illustrates a bottom view of a first embodiment of the humeral nail in an actuated position. 
         FIG. 32  illustrates a top view of a first embodiment of the humeral nail in an actuated position. 
         FIG. 33  illustrates a top view of a first embodiment of the nail end cap. 
         FIG. 34  illustrates a side view of a first embodiment of the nail end cap. 
         FIG. 35  illustrates a cross-sectional view of a first embodiment of the nail end cap. 
         FIG. 36  illustrates a top view of a first embodiment of the actuation screw. 
         FIG. 37  illustrates a side view of a first embodiment of the actuation screw. 
         FIG. 38  illustrates a cross-sectional view of a first embodiment of the actuation screw. 
         FIG. 39  illustrates a first view of a first embodiment of the locking screw. 
         FIG. 40  illustrates a second view of a first embodiment of the locking screw. 
     
    
    
     DETAILED DESCRIPTION 
     Reference will now be made in detail to the presently preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Throughout the following detailed description, the same reference numerals refer to the same elements in all figures. 
     Referring to  FIGS. 1-2 , the humeral nail  40  is shown. The humeral nail  40  is shown inserted into the intramedullary canal  10  of the humerus  2 , the humerus having a proximal portion  4 . An exemplary fracture line  6  is shown, the fracture line  6  representing a surgical neck fracture. Other types of fractures that can be treated using the humeral nail  40  include fractures of the anatomical neck and fractures of the greater tuberosity. 
     The humeral nail is adaptable to work in any long bone, the tibia being one such example. 
     Locking screws  12 ,  14 ,  16 , and  18  are shown. The number of screws used and the choice of which screws is made by the surgeon. 
     Upper nail tangs  141  and lower nail tangs  140  are shown in their fully extended position. 
     Referring to  FIGS. 3-4 , the humeral nail  40 , with its internal components, is further described. 
     This embodiment of the humeral nail  40  is cylindrical in cross-section, and straight along its length, but neither shape is a requirement. Alternative cross-sections such as square, hex shaped, or lobular, allow for linear motion of internal components while fixing rotational position. Alternative shapes along its length are also acceptable, likely chosen to mimic the shape of the bone into which the nail must fit. 
     The two primary components of the humeral nail  40  are the nail body  42  and the linear tang actuator  30 . The nail body  42  includes a distal portion  44  and a proximal portion  46 . The nail body  42  has a nail body distal outside diameter  48 , a nail body transitional diameter  50 , and a nail body proximal outside diameter  52 . The distal portion  44  of nail body  42  has a nail distal end bore  54  with nail distal bore diameter  58 . 
     The distal portion  44  of the nail body  42  has a rounded tip to ease insertion into the intramedullary canal  10  (not shown). Other tapered shapes are also acceptable, including a chamfered tip. 
     The upper tangs  141  and lower tangs  140  have pre-curved tips  150 . The pre-curved tips  150  have nail tang slant angle  65 . 
     The upper tangs  141  and lower tangs  140  pass through nail tang portals  60  present in the nail body  42 . The presence of multiple sets of tangs creates additional fixation, but one set of tangs is acceptable. As the tangs pass through the nail tang portals  60  they slide against the nail portal slanted surfaces  62 , which each have a nail portal slant angle  64  relative to the longitudinal axis of the nail body  42 . The result, as shown in later figures, is bending of the nail tangs  140 / 141 , resulting in curved nail tangs  140 / 141 . 
     During assembly, the linear tang actuator  30  is inserted into the nail body  42  until the linear tang actuator rest surface  136  rests against the nail body rest surface  70 . The linear tang actuator  30  is shown as a single piece, but could be constructed of multiple pieces. Such multiple pieces could be fused together, affixed mechanically, or be able to move with respect to one another. 
     Turning to fixation of the proximal end of the humeral nail  40 , each lock screw  12 / 14 / 16 / 18  has corresponding lock screw portals  80 / 82 / 84 / 86 . First locking screw  12  is inserted through first lock screw portals  80 . Second locking screw  14  is inserted through second lock screw portals  82 . Third locking screw  16  is inserted through third lock screw portals  84 . And fourth locking screw  18  is inserted through fourth lock screw portals  86 . 
     The proximal portion  46  of the nail body  42  includes numerous features that provide for interaction between the nail body  42  and linear tang actuator  30 . The nail proximal bore  90  is the inner bore within the proximal end of the nail body  46 , through which the linear tang actuator  30  passes during assembly of the humeral nail  40 . A portion of the nail proximal bore  90  is threaded, creating the nail proximal threads  92 . 
     As discussed above, the linear tang actuator  30  is moved through use of actuation screw  100 . The first actuation threads  102  of the actuation screw  100  mate with the second actuation threads  106  of the linear tang actuator  30 . Rotation is performede using a tool (not shown) that interfaces with the actuation head  104  of the actuation screw  100 . 
     Following actuation, the proximal portion  46  of nail body  42  is covered by the nail end cap  96 , which interfaces with the nail proximal threads  92 , resting against the nail end cap seat  94 . 
     Referring to  FIGS. 5-8 , pre and post actuation views of the linear tang actuation are shown. As discussed above, the humeral nail allows for actuation of the nail tangs  140 / 141  after the locking screws  12 / 14 / 16 / 18 . One embodiment of a mechanism that allows for this actuation is shown in the figures. The linear tang actuator  30  is shaped to move around the locking screws, allowing for the axial force to be transferred from the actuation screw  100  at the top of the humeral nail  40  to the tangs  140 / 141  at the bottom of the nail. The linear tang actuator  30  passes around the locking screws  12 / 14 / 16 / 18 , transmitting the force from the actuation screw  100  to the tangs  140 / 141 ; bridging the two ends of the humeral nail  40  to move the force around the locking screws  12 / 14 / 16 / 18 . 
       FIG. 5  shows a partial-sectional side view of the locking screws  12 / 14 / 16 / 18  interacting with the linear tang actuator  30  prior to actuation. 
       FIG. 6  shows a cross-sectional view of the locking screws  12 / 14 / 16 / 18  and linear tang actuator  30 , prior to actuation. 
       FIG. 7  shows a partial-sectional side view of the locking screws  12 / 14 / 16 / 18  interaction with the linear tang actuator  30  after complete actuation. 
       FIG. 8  shows a cross-sectional view of the locking screws  12 / 14 / 16 / 18  and linear tang actuator  30 , after complete actuation. 
       FIGS. 5-6  show the relationship of the linear tang actuator  30 , locking screws  12 / 14 / 16 / 18 , and actuation screw  100  prior to actuation of the mechanism, and thus before extension of the tangs  140 / 141  (not shown). The actuation screw  100  is braced against the fourth locking screw  18 . The first actuation threads  102  of the actuation screw  100  are threaded into the second actuation threads  106  of the linear tang actuator  30 . As the actuation screw  100  is turned, the interaction of the threads  102 / 106  draws the linear tang actuator  30  upwards. The result is a reduction in the distance between the proximal end  32  of the linear tang actuator  30  and the proximal end  46  of the nail body  42 , pulling the linear tang actuator  30  upwards. The upward force of the first actuation threads  102  against the second actuation threads  106  is countered by a downward force by the actuation screw  100  against the fourth locking screw  18 . 
     Nail end cap  96  is cannulated, or has a central penetration, which is useful for nail removal. When the actuation screw  100  is turned in a reverse direction, rather than bracing against the fourth lock screw  18  the actuation screw  100  braces against the inner portion of the nail end cap  96 . This allows the actuation screw  100  to provide a downward force against the linear tang actuator  30 . 
       FIGS. 7-8  show the relationship of the linear tang actuator  30 , locking screws  12 / 14 / 16 / 18 , and actuation screw  100  after complete actuation of the mechanism, and thus after extension of the tangs  140 / 141  (not shown). The actuation screw  100  has drawn the linear tang actuator  30  completely upward. The upper portion of the linear tang actuator  30  has filled the space between the actuation screw  100  and the nail end cap  96 . While this will be more thoroughly explained in subsequent figures,  FIG. 8  shows the movement of the linear tang actuator  30  around the locking screws  12 / 14 / 16 / 18 . 
     Referring to  FIG. 9-12 , pre and post actuation views of the linear tang actuation are shown with the nail body  42  hidden to show the interaction of the linear tang actuator  42  and the locking screws  12 / 14 / 16 / 18 . 
     Referring to  FIG. 13-18 , pre and post actuation views of the linear tang actuation are shown, with different views showing the compression action of the keyhole shaped slots. 
     The linear tang actuator  30  has keyhole-shaped slots for the penetration of locking screws  12 / 14 / 16 / 18 . This provides two specific advantages over the prior art. First, the keyhole-shaped slots grip and compress the locking screws  12 / 14 / 16 / 18  after actuation, preventing the screws from backing out. Second, the shape of the slots allows for the reduction process to be completed and locking screws  12 / 14 / 16 / 18  to be installed before tang  140 / 141  extension. 
     Comparison of the figures shows that the screws are non-co-planar. If the axis of each locking screw  12 / 14 / 16 / 18  is viewed as lying within a plane, locking screw  12  does not share a plane with locking screw  14 , nor locking screw  12  with locking screw  16 . In this embodiment, locking screw  12  and locking screw  18  share a plane, but in other embodiments these locking screws  12 / 18  do not. The result is that the keyhole-shaped slots within the linear tang actuator are non-co-planar. 
     The linear tang actuator  30  allows for the transmission of force around a multiplicity of non-co-planar locking screws  12 / 14 / 16 / 18 , each non-co-planar locking screw  12 / 14 / 16 / 18  penetrating the linear tang actuator  30  through its own slot, the result being that each slot is non-co-planar. 
     Each locking screw has an associated keyhole-shaped slot. Each slot has a larger upper, or proximal, portion where the locking screw  12 / 14 / 16 / 18  is inserted during reduction. The slot immediately narrows, and as a result the rising motion of the linear actuator brings the narrower portion of the keyhole shaped slots to bear on each respective locking screw  12 / 14 / 16 / 18 , squeezing the screw and holding it in place. This squeezing force prevents the screws from backing out. Because the extension of the tangs  140 / 141  can be stopped at any point the surgeon deems appropriate, it is helpful that the locking screws  12 / 14 / 16 / 18  become fixed as soon as the tangs  140 / 141  begin extension. The squeezing force then remains continuous throughout the remaining travel of the linear tang actuator  30 . 
     The first locking screw  12  has a first locking screw broad gap  20  and a first locking screw narrow gap  21 . The second locking screw  14  has a second locking screw broad gap  22  and a second locking screw narrow gap  23 . The third locking screw  16  has a third locking screw broad gap  24  and a third locking screw narrow gap  25 . The fourth locking screw  18  has fourth locking screw broad gap  26  and a fourth locking screw narrow gap  27 . Each combination of a broad gap and a narrow gap results in a keyhole-shaped slot. 
     Alternative means of drawing the linear tang actuator  30  upwards exist. Examples included a tool that draws the linear tang actuator  30  upward much like the actuation screw  100 , but braces against the nail body  42 , or other external surface, rather than the fourth locking screw  18 . The benefit of this arrangement is that the fourth locking screw  18  is no longer required. This tool would interface with the second actuation threads  106  of the linear tang actuator  30  to draw the linear tang actuator  30  upwards. 
     Alternatively, a linear ratchet tool could be used. Such a tool would also brace itself against the nail body  42  or other external surface, but would not draw the linear tang actuator  30  upwards by rotating a screw within the second actuation threads  106 , but instead by a linear (non-rotational) ratcheting action. The linear ratchet tool would draw the linear tang actuator  30  upwards an incremental amount, reset, and repeat. When the upward amount was correct the linear ratchet tool would be removed, and a modified cap screw installed that threaded into the second actuation threads  106  and interfaced with the nail end cap seat  94  to prevent the linear tang actuator  30  from moving downward. 
     Referring to  FIG. 19 , an isometric view of the linear tang actuator  30  is shown. 
     Referring to  FIG. 20 , a front view of the linear tang actuator  30  is shown. 
     Referring to  FIG. 21 , a back view of the linear tang actuator  30  is shown. 
     Referring to  FIG. 22 , a right view of the linear tang actuator  30  is shown. 
     Referring to  FIG. 23 , a left view of the linear tang actuator  30  is shown. 
     Referring to  FIG. 24 , a top view of the linear tang actuator  30  is shown. 
     Referring to  FIG. 25 , a bottom view of the linear tang actuator  30  is shown. 
     Referring to  FIG. 26 , a cross-sectional view of the linear tang actuator  30  is shown. 
     Referring to  FIG. 27-28 , the operation of the tangs is shown. The tangs  140 / 141  include pre-curved tips  150 . The shape of the nail tang pre-curved tips  150  performs a number of functions: First, the tangs  140 / 141  extend in the upward direction, toward the proximal portion  46  of the nail  40 . Because the proximal portion  46  of the nail  40  is affixed to the humerus  2  before the tangs are extended, the proximal portion  46  of the nail  40  is fixed. The upward motion of the tangs  140 / 141  pulls the distal portion  44  of the nail  40  downward, correspondingly pushing the distal portion of the humerus  2  upward. The result is compression of the fracture line  6 . This compressive action stabilizes the bone, allowing the patient to use the arm sooner in the recovery process. Closing the gap minimizes the amount of bone the body must regenerate, and thus reduces the time required for full recovery. 
     There is no requirement that the surgeon extend the tangs a specific amount. 
     Second, during assembly, when the nail tangs  140 / 141  are moved into place in the distal portion of the nail body, the nail tang pre-curved tips  150  of the opposing nail tangs  140 / 141  snap, or pop, into their respective nail portals  60 . The self-locating feature of the nail tangs  140 / 141  with the nail tang pre-curved tips  150  simplifies assembly, and ensures that the tangs are properly located. 
     Third, in this installed position, the nail tang pre-curved tips  150  rest against the nail portal slanted surfaces  62 . The nail portal slanted surfaces  62  serve to smoothly guide the opposing nail tangs  140 / 141  through their path to exit the nail body  42 . The pre-curved nature of the tips  150  begins the process of plastic deformation of the opposing nail tangs  140 / 141  as they exit the nail tang portals  60 , guided by the nail portal slanted surfaces  62 . The angle  64  of the slanted surfaces  62  controls the shape of the opposing nail tangs  140 / 141  during the process of plastic deformation. Much as a die is used to create an extruded shape during extrusion, the shape of the nail portal  60  and angle  64  of the nail portal slanted surface  62  serves to shape each opposing nail tang  140 / 141  as it passes through. 
     Fourth, the shape of the nail tang pre-curved tips  150  shape allows the opposing nail tangs  140 / 141  to be present in the nail tang portals prior to extension. This allows the opposing nail tangs  140 / 141  to almost immediately contact the interior surface of the bone. The result is a reduction in surgery time and fewer turns required prior to contact. As a result, the humeral nail  40  is less likely to rotate out of place during actuation. 
     Referring to  FIG. 29 , a bottom view of the humeral nail  40  is shown. The humeral nail  40  is in the non-actuated position, thus the tangs  140 / 141  are not visible. 
     Referring to  FIG. 30 , a top view of the humeral nail  40  is shown. The humeral nail  40  is in the non-actuated position, thus the tangs  140 / 141  are not visible. 
     Referring to  FIG. 31 , a bottom view of the humeral nail  40  is shown. The humeral nail  40  is in the actuated position, thus the tangs  140 / 141  are visible. It can be seen that in this embodiment the upper tangs  141  and lower tangs  140  are offset by sixty degrees. 
     Referring to  FIG. 32 , a top view of the humeral nail  40  is shown. The humeral nail  40  is in the actuated position, thus the tangs  140 / 141  are visible. 
     Referring to  FIGS. 33-35 , the nail end cap  96  is shown. The nail end cap  96  is shown with a Torx type interface, but any interface is acceptable. 
     Referring to  FIG. 36-38 , the actuation screw  100  is shown. The actuation screw  100  is shown with a Torx type interface, but any interface is acceptable. 
     Referring to  FIG. 39-40 , the locking screw  12 / 14 / 16 / 18  is shown. Optional locking screw  12 / 14 / 16 / 18  features include self-tapping, where the screw creates its own thread (shown); and self-drilling, where the screw creates its own hole, in addition to self-tapping. 
     The suture holes  19  can be used as anchor points for surgical sutures. Sutures may be used during surgery for fixation of the lesser tuberosity, or suturing the rotator cuff. 
     Equivalent elements can be substituted for the ones set forth above such that they perform in substantially the same manner in substantially the same way for achieving substantially the same result. 
     It is believed that the system and method as described and many of its attendant advantages will be understood by the foregoing description. It is also believed that it will be apparent that various changes may be made in the form, construction and arrangement of the components thereof without departing from the scope and spirit of the invention or without sacrificing all of its material advantages. The form herein before described being merely exemplary and explanatory embodiment thereof. It is the intention of the following claims to encompass and include such changes.