Abstract:
A surgical tool including an elongated housing having an outer diameter at a location adjacent the front end which can pass through a targeting tunnel of a targeting guide. The surgical tool also includes a first blade with a first cutting edge, a second blade with a second cutting edge, each blade being movably connected adjacent to a first end of an actuation mechanism in the elongated housing. The blades include an at-rest scissors position and a scalpel position. When in the at-rest position the width of the blades does not extend beyond an outer diameter of the elongated housing and when the blades are in a scalpel position, the blades extend beyond the outer diameter of the elongated housing.

Description:
This patent application is a divisional of application Ser. No. 13/461,460 filed on May 1, 2012, now U.S. Pat. No. 9,089,357 B2. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to the field of orthopedic surgery and in particular to making incisions in the skin and soft tissues to go directly to the surface of a fractured bone to affix locking screws into the bone. The present invention further relates to the use of a locking nail and guide means to reach to the surface of the bone so that a proper incision can be made to enable a locking screw to be affixed into the bone and the embedded locking nail with a minimum of surgical cutting and blood loss. The present invention also relates to the field of scalpels used to make the required incision so that a locking screw can be affixed into the bone with a minimum of surgical cutting and blood loss. 
     2. Description of the Prior Art 
     The fairly recent development of intra-medullary locking nails has been a significant breakthrough in the surgical management of fractures of the long bones in humans and animals. 
     Locking nails provide superior fixation to that provided by on-lay plates secured by screws. Equally significantly, they can be installed in the bone with far less surgical injury to the patient. The skin incisions are smaller. The soft-tissue trauma is less. The amount of blood-loss is much less. The overall recovery from surgery is speedier and more pain-free. The impact of locking nails on the surgical management of long-bone fractures cannot be overstated. 
     The installation of a locking nail, which is a long metal rod and will be interchangeably referred to as a rod or a nail, is accomplished by inserting it, through a small skin incision, into one end of the bone, and advancing it into the bone cavity (medullary cavity) so that the rod is embedded within that cavity. This metal rod has preformed holes at intervals along its length for receiving screws that are inserted transversely or obliquely through the shaft of the bone. In this way the traversing screws lock the bone fragments to the embedded rod, or conversely, lock the rod to the bone. Each traversing screw is inserted into the bone through a small skin incision, and herein lays the problem. 
     For the placement of each traversing screw, the technical problems for the surgeon include, firstly, making the small skin incision at the correct location and correct angle on the skin surface, and extending the incision through the skin and soft-tissues, down to the bone surface. Instruments are now passed through this small skin and soft-tissue path, to drill a hole that passes through one side of the bone, through r 3  the unseen hole in the rod, and into the bone on the far side of the rod. 
     The challenge of finding the exact spot on the bone&#39;s outer surface to drill the first hole, and then to drill in precisely the right direction for the drill bit to pass centrally through the hole in the rod, has been ingeniously solved by the use of a targeting guide. The targeting guide is attached to an outrigger that is rigidly, and removably, attached to one end of the rod. When the nail is embedded in the bone, this attached outrigger and targeting guide protrude from the insertion wound, and lie outside the body. Note that in some device brands, the outrigger and targeting device are a single part. The targeting guide lies parallel with the embedded nail. Within the targeting guide, along its shaft, are tunnels (the targeting guide tunnels) that line up precisely with the holes in the embedded, and unseen, rod. In placing a screw through the bone and the hole in the embedded rod, various instruments are passed through the matching targeting guide tunnel in the targeting guide. Drill bits are long and narrow and sometimes brittle, and their rotating motion can damage soft-tissues. For this reason they are supported and guided, and the tissues are protected from them, by passing them through a metal sheath, the drill-guide. There is no standard nomenclature in the industry for the terms “outrigger”, “targeting guide” and “targeting guide tunnel”, but the usage of these terms in this patent application can leave no doubt as to the meaning of these terms as used here. 
     The drill guide is a metal tube that has an outer diameter such that it snugly passes through the matching targeting guide tunnel. The inner diameter of the drill guide is such that the drill bit snugly passes through it. Its leading edge cones down to a bullet-nose. 
     As a first step for inserting a screw through the wall of the bone and into the underlying rod-hole, the drill-guide is inserted into the matching targeting guide tunnel. The drill guide is advanced to the skin. A mark is made at the site of skin contact. The drill guide is withdrawn, and an incision is made through the skin and soft-tissues until the scalpel blade reaches the bone. 
     The drill guide is now advanced through this skin incision and soft-tissue path, until its advancing end comes into contact with the bone. The drill-guide, thus placed, is now perfectly located to guide a drill bit to the correct site on the surface of the bone, at precisely the correct angle, to drill through the bone and through the hole in the rod. The drill bit is then advanced deeper into the bone, or out through the opposite cortex (wall) of the bone. Once a hole has been drilled through the bone and the hole in the rod, the drill guide is removed from the targeting guide tunnel and a screw guide sleeve is inserted into the targeting guide tunnel. The screw guide sleeve is used to guide the screw and the screwdriver to the nearside hole in the bone, and through it to the hole in the nail, and out through the hole into the bone on the other side of the nail. 
     The current practice for cutting the skin incision and a path through the soft-tissues down to the bone is crude and imprecise. The current practice starts wherein the skin entry-site is located by advancing the drill guide through its targeting guide tunnel until it touches the skin. A mark then is made on the skin at the contact site. The drill guide is partly withdrawn away from the skin but is left in the targeting guide tunnel. The surgeon then makes a free-hand skin incision at the marked skin site, using a regular, standard, single-bladed scalpel. The bulky targeting guide blocks direct access to the skin and the surgeon has to work around it. The only direct access to the marked skin site would be though a targeting guide tunnel. As things currently stand, the scalpel is now directed in front of or behind the targeting guide, angled obliquely through the skin incision and soft-tissues, at an approximately anticipated compensating angle, to a mentally calculated and imprecise location on the bone surface. Because this is not the best angle for the incision, the surgeon makes an oversized, irregular skin cut and soft-tissue path that is not at an ideal angle. 
     For the scalpel to make the skin incision and soft-tissue path at the correct angle and with the shortest path from the skin to the bone would require that the scalpel pass directly though the targeting guide tunnel. Since the targeting guide tunnel guides the drill guide to the precise location on the bone for drilling the hole into the bone, the same tunnel could usefully serve to accurately guide a scalpel through the skin and soft-tissues to the same, precise target point on the bone. 
     One problem with this solution is that commercially available scalpels do not have handles that are long enough to pass through the targeting guide tunnel and cover the distance down to the bone. If the a scalpel had a longer handle, the surgeon could make a straight pass with the blade, directly through the targeting guide tunnel, through the skin and soft tissues, and down to the bone. 
     The above solution by itself is not presently viable because an incision made through the targeting guide tunnel with the currently available fixed-blade scalpels would be too small to accommodate the drill guide or the screw driver sleeve. This is because the widest blade that could pass through the targeting guide tunnel would have a width equal to the internal diameter of the targeting guide tunnel. However, a skin incision whose length equals the internal diameter of the targeting guide tunnel would be insufficient to allow passage of a cylindrical instrument (such as the drill guide) that has an external diameter that equals the internal diameter the targeting guide tunnel. If the skin had no elasticity, the length of the smallest skin incision that will allow passage of the drill guide can be calculated; it is equal to half the circumference of the drill guide. The circumference (C) of the cylindrical drill guide is calculated as π multiplied by the diameter (D) of the drill guide (C=πD). Thus, if the diameter of drill guide were 10 mm, the circumference of the drill guide would be 3.14 multiplied by 10 mm, which equals a circumference of 31.4 mm. In non-elastic skin the length (L 1 ) of the smallest skin incision that would accommodate the drill guide would therefore be half the circumference (C) of the drill guide. L 1 =πD×0.5 Thus, in non-elastic skin, a skin incision 15.7 mm long is needed for a 10 mm cylindrical drill guide to pass through it: i.e. an incision that is 57% longer than the diameter of the cylindrical drill guide. It can be seen that at present, the widest scalpel blade that could pass through a 10 mm diameter targeting guide tunnel, cannot be 15.7 mm wide, but instead only 10 mm wide, and further, that a 10 mm rigidly guided scalpel blade cannot make an incision that is greater than 10 mm wide, such as the 15.7 mm that is needed in the present example, if the scalpel cuts only in a thrusting mode, with no side to side slicing motion. This percentage is constant: in non-elastic skin, the incision needed for passage of a cylindrical instrument will need to be 57% longer than the diameter of that instrument for all sizes of instrument. 
     Human skin does have elasticity, and normally, an incision in human skin will stretch 25% to 30%. This is still less than the 57% needed for a cylindrical instrument to pass through a skin incision that equals in length the diameter of that cylindrical instrument. 
     Therefore, even allowing for the elasticity of normal human skin, the widest, fixed-blade scalpel blade that could be passed through any size targeting guide tunnel could not make a skin incision adequate for the passage of the corresponding drill guide. 
     Given the elasticity of human skin, the present invention scalpel instruments can make an incision that is less than the 57% enlargement, and still be adequate. 
     Assuming a skin stretch of 25%, a 12.6 mm incision will stretch to 15.75 mm, which is sufficient for the passage of a 10 mm cylindrical instrument. This is 2.6 mm (26%) greater than the drill guide diameter of 10 mm. 
     In summary, assuming a skin incision that will stretch 25%, the incision will need to be 26% longer than the diameter of any cylindrical instrument, to enable the said instrument to pass through that incision. 
     Locking screws placed through the lateral aspect of the proximal femur have to pass through a tough, inelastic fascial layer, called the fascia lata. The fascia lata poses a special problem over the proximal femur in locking nail fracture fixation. The iliotibial band is not quite as thick or tough as the fascia lata, but it poses a similar problem over the lateral aspect of the distal femur. The term “deep fascia” will be used to describe either. The deep fascia forms a barrier to the passage of the drill guide and other instruments. It lies against the bone at the deepest part of the narrow soft tissue incision tunnel. A pointed knife thrust straight into it will only make a small puncture hole. Slicing motion is required to adequately enlarge the puncture hole for passage of the instruments. It is impossible to enlarge the puncture hole without enlarging the soft tissue tunnel as well, thereby causing additional soft tissue damage. 
     In current practice, the surgeon passes the scalpel anterior or posterior to the targeting guide and through the skin and soft tissues, to blindly slice the deep fascia. Made in this oblique fashion, the fascial incision does not line up perfectly with a straight line between the targeting guide tunnel and the target point on the bone surface. The surgeon therefore makes long sweeping motions with the tip of the knife, making an unnecessarily oversized fascial incision. The fascial incision cannot be repaired later, since it lies in the depth of a narrow soft-tissue tunnel. The fascia lata connects to the iliotibial band. Both play a vital role in normal gait. Excessive damage to the fascia lata or iliotibial Band may later result in impaired gait. 
     There are many “perforating” arteries just deep to the fascia lata. The larger the fascial incision the more blood vessels will be cut, causing proportionately increased bleeding. 
     A tunnel-guided-knife as described herein will predictably make the smallest possible skin and soft tissue incision. However, a sharp-pointed blade plunged through the skin straight down to the bone, and then withdrawn back along the identical path, guided in and out by the rigid targeting guide tunnel, will have a terminal configuration that strictly matches the profile of the blade. 
     Any blade, other than a chisel-shaped blade, will always have a sharp-pointed leading edge, which will cause the terminal end of the tunnel to be triangular. A chisel-blade is impractical since it will not penetrate the skin. A triangular end-tunnel will be of no consequence where the entire tunnel is through soft tissues, such as fat and muscle. However, the deep facia along the lateral thigh is a tough barrier that lies adjacent to the bone. 
     Any in-and-out blade, other than a chisel, will penetrate the deep fascia with an incision that is always less than the full width of the blade, and likely to be little more than a puncture point. Enlarging the deep fascial incision with a pointed blade would require side-to-side slicing motion, which is not possible with a fixed blade, attached to a rigid cylindrical handle, which is guided by a rigid targeting guide tunnel. Making a minimal incision in the deep fascia at the terminal end of a minimal skin and soft tissue tunnel thus represents a special challenge in using a tunnel-guided knife. 
     For the sake of speed and convenience, given the technical problems of blindly passing a scalpel anterior or posterior to the targeting guide, surgeons frequently make an initial skin incision, soft-tissue path and fascial incision that is much larger than the minimum needed to get the job done. Alternatively, the surgeon may start with a small, tentative skin incision and enlarge it when he/she finds that it is too small for the drill guide to pass through. This free hand, secondary enlargement will often result in a jagged incision, and the subsequent healed scar will be jagged and cosmetically unsatisfactory. 
     Additionally, skin incisions and soft-tissue tunnels must be made for each screw, and there is at least one and generally multiple screws that must be applied. At the end of the operation the surgeon has to close each of the individual skin wounds, a process which can be time-consuming, the total time being directly related to the length of each incision. 
     In the operation of locking nail fracture fixation, there are compelling reasons for the locking-screw incisions through the skin, soft tissues and deep fascia to be as small as possible. The smallest incisions can only be made through the targeting guide tunnel. Ideally each incision needs to be just large enough to accommodate the outer diameter of the drill guide. Skin and soft tissue incisions made through the targeting guide tunnel with a fixed-blade scalpel are too small. A pointed knife thrust straight into the deep fascia through the targeting guide tunnel will only make a small puncture hole, and slicing motion is required for an adequate incision. 
     SUMMARY OF THE INVENTION 
     The present invention is a multi-functional double bladed surgical tool. The present invention resolves all the problems discussed above. The present invention is a method and a surgical instrument for predictably and efficiently making the skin incision, soft-tissue path and deep fascial incision, with the smallest, least damaging, and most precise incision. The present invention makes the quickest, cleanest, most precise incision from the skin to the bone than has been seen in the prior art. Additionally, the resulting incision will be much less traumatic than can be made free hand, with a conventional scalpel. It will also enable the surgeon to make the incision quicker and easier, complete the surgery quicker and easier, and allow the patient to heal with less scarring and with less likelihood of, and reduction of adverse secondary effects. 
     The present invention also relates to a method and apparatus for efficiently making a skin incision and a soft-tissue path from the skin to the bone. The invention herein relates more specifically to a surgical method and a surgical instrument, heretofore unseen in the prior art, for making a skin incision and soft-tissue path from the skin to the bone, and for making the smallest, least damaging, most precise skin incision and soft-tissue path to the bone, and doing so in a manner that is quicker and easier for the surgeon and resulting in the overall operation being quicker and easier for the surgeon, and the patient experiencing less trauma, less scarring, greater healing and less likelihood of damaging or adverse side effects. 
     Described herein is a method and novel instrument for making an incision of precise and minimal dimensions, in a precise and exact direction, having the shortest path from the skin to the bone. The result is the smallest skin and soft-tissue incision possible, made speedily and accurately. It will be seen that this additionally results in the least amount of tissue trauma possible, shortened operating and anesthesia time, and less blood loss. Further, the incision is easier to repair, and heals with a cosmetically superior scar. 
     Additionally described herein, is a technique and instrument for making a skin and soft-tissue incision utilizing the targeting guide. Since the targeting guide tunnel guides the drill guide to the precise location on the bone for drilling the hole into the bone, the same targeting guide tunnel can usefully serve as the perfect targeting device for guiding a scalpel through the skin and soft-tissues to the same target point on the bone. In order to do so, the scalpel handle will need to be a cylinder. Conventionally, scalpel handles are flat in order to give the surgeon maximum, ergonomic, manual control over the direction and rotation of the cut. However, a scalpel with a cylindrical handle having a diameter that is the same as that of the targeting guide tunnel through which it is being passed will be provided maximum directional control by the targeting guide tunnel. The surgeon&#39;s wet, gloved hand may still have difficulty with rotational control over the smooth cylindrical handle, and therefore the blade. This can be overcome by flattening opposite surfaces of the cylindrical handle so that the handle becomes a partial cylinder. Thus, regardless of the shape of the handle, so long as its perimeter fits snugly within the inner diameter of the targeting guide tunnel, the goals and advantages of the present invention will be achieved. 
     The present invention further overcomes the problem that presently available conventional scalpels are six to eight inches long, which is insufficient to achieve the objectives of the present invention. The barrel of the present invention scalpel instrument will be longer to pass through the targeting guide down to bone, and still leave sufficient handle protruding for the surgeon to grasp. 
     The present invention further overcomes the problems with the prior art scalpels by creating a scalpel instrument that is capable of achieving the objectives of the invention. The present invention apparatus is a novel scalpel instrument that can be passed through the targeting guide tunnel to accurately make a most minimal but adequate incision to accommodate the drill guide and other instruments. 
     In a first embodiment, two or more blades are employed to form the cutting edge. The present invention teaches a means for radially narrowing the cutting edge of the blades of the scalpel instrument for inward passage through the targeting guide tunnel, a means for radially restoring the blades and their cutting edge to its full width after passage through the targeting guide tunnel in preparation for making an adequate skin incision, and a means for radially narrowing the blades and their cutting edge for withdrawal of the scalpel through the targeting guide tunnel after the incision has been made. 
     The present invention also teaches a means for accurately and predictably making a most minimal but adequate, incision in the deep fascia, at the exact and precise location that it is needed, by means of the two blades functioning together as a surgical scissors apparatus, or viewed alternately as two blades each independently making slicing incisions in the deep fascia. The present invention teaches a means for making the blades of a single instrument function interchangeably as a surgical scalpel and a surgical scissors. The present invention teaches the method of making a cruciate incision in the deep fascia as being the most minimal, least damaging incision possible 
     In a second embodiment, the present invention teaches a means for creating an adequate incision using a single-blade scalpel, wherein the blade rotates for deployment. 
     The innovative and novel scalpel instruments of the present invention may be made available with barrel handles of different diameters. The surgeon selects a scalpel of suitable barrel diameter to match the targeting guide tunnel of the manufacturer-specific locking nail device in use. For each scalpel barrel diameter, the cutting edges will make adequate skin and fascial incisions to accommodate passage of instruments of matching diameter, through the resulting skin and deep fascial incisions. The present invention scalpel could be used with the instrumentation of any locking nail manufacturer, as long as the correct scalpel barrel diameter is selected to fit that targeting guide tunnel. 
     The cutting edge of the first embodiment of the present invention scalpel instrument contracts radially for inward passage through the targeting guide tunnel, then expands radially for making the incision, and again contracts radially for the exit passage through the targeting guide tunnel. The mechanism for causing the cutting edge of the scalpel to expand or contract radially is immaterial to the apparatus, method, technique, objectives, and principles described in this patent. It is within the scope of the present invention that the mechanism for causing the cutting edge of the scalpel to expand or contract radially could utilize alternative methods, or use one or more blades to achieve the same desired result. 
     In the preferred embodiment and method, two or more blades are mounted within the scalpel barrel, near the leading edge of the scalpel. In the contracted position of the blades, the cutting edge does not protrude radially beyond the profile of the scalpel barrel. A mechanism actuated by the surgeon causes the blades to protrude radially from the handle when needed. The blades are configured in such a way that, in the radially protruded position, they act together, as a single cutting edge that is wider than the scalpel barrel. The two blades are also configured so that in moving from the contracted to the protruded position and back again the blades function together as a surgical scissors. A single instrument thus functions interchangeably as a scalpel and a surgical scissors. 
     The present invention method and scalpel instrument is discussed here for illustrative purposes as used in orthopedic surgery. This description in no way implies that the use of the knife, or the technique, is limited to orthopedic surgery, limited to fracture surgery, limited to surgery on bone, or limited to surgery on humans. 
     Further novel features and other objects of the present invention will become apparent from the following drawings, detailed description and discussion. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Referring particularly to the drawings for the purpose of illustration only and not limitation, there is illustrated: 
         FIG. 1  is a plan view of a preferred embodiment of the present invention scalpel instrument illustrating the position wherein the two blades are radially expanded and in a convex V-shape configuration; 
         FIG. 2  is a plan view of a preferred embodiment of the present invention scalpel instrument illustrating the position wherein the two blades are radially retracted and in the concave V-shape or open-scissors position; 
         FIG. 3  is a detail of a preferred embodiment of the present invention scalpel instrument with the cutting edges of the two blades in the concave V-shape or open scissors formation, the illustration in a partially open condition to show the actuation mechanism; 
         FIG. 3A  is a detail of a preferred embodiment of the present invention scalpel instrument with the cutting edges of the two blades illustrated in a convex V-shape radially expanded condition not illustrating the internal actuation mechanism as in  FIG. 3   
         FIG. 3B  is a detail of the two blades of the preferred embodiment of the present invention scalpel separated so that the angular slots in each blade are visible; 
         FIG. 3C  is a detail of the two blades of the preferred embodiment of the present invention scalpel illustrated with one blade crossing over the other blade during a portion of a scissors-action cycle; 
         FIG. 4  is a detail of a preferred embodiment of the present invention scalpel instrument illustrating a preferred means of radially expanding the two blades, and the position of the cutting edges of the two blades in the convex V-shape radially expanded, formation, the illustration in a partially open condition to illustrate the actuation mechanism; 
         FIG. 4A  is a detail of a preferred embodiment of the present invention scalpel instrument illustrating the position of the cutting edges of the two blades in the concave V-shape or open scissors formation, the illustration shown in a totally closed condition and not illustrating the interior actuation mechanism as in  FIG. 4 ; 
         FIG. 5  is an exploded view of the insertion device of the locking nail, including a locking nail, a targeting device, and an outrigger; 
         FIG. 6  is a perspective view of a locking nail, a targeting device and an outrigger, joined together, illustrating the relationship of the three to each other; 
         FIG. 7  is an illustration, not to scale, of a partial cross-section of a bone covered with skin and soft tissues with the locking nail inserted into the bone and a perspective view of the aligned targeting guide in place with the present invention scalpel instrument inserted through a targeting guide and the deployed blades moved out of the scalpel and presented to and about to penetrate the skin and soft tissues with the scalpel blades in a convex V-shape formation; 
         FIG. 8  is a detail illustration of prior art and the presentation of prior art scalpel advanced through the skin and soft-tissue to a bone; 
         FIG. 9  is a detail illustration of prior art and the inadequacies of the incision and soft-tissue tunnel to the bone; 
         FIG. 10  is a detail illustration, not to scale, the next step after  FIG. 7 , wherein there is illustrated a cross-sectional view of the preferred embodiment of the present invention scalpel instrument in use in the method of the present invention, wherein the blades of the scalpel instrument are in the convex V-shape formation and have advanced through the skin and soft-tissue, penetrated the deep fascia, and have reached the bone; 
         FIG. 11  is a detail illustration, not to scale, of the next step after  FIG. 10  wherein there is illustrated a cross-sectional view of the preferred embodiment of the present invention scalpel instrument in use in the method of the present invention, wherein the blades of the scalpel instrument are in the convex V-shape formation, and having reached the bone in  FIG. 10 , and are now being withdrawn; Also illustrating that a soft-tissue tunnel has been made in the skin and soft tissues from the previous steps; the terminal end of the tunnel is convex V-shaped, the deep fascia has been penetrated by the sharp tip of the scalpel; 
         FIG. 12  is an illustration, not to scale, of the next step after  FIG. 11  wherein there is illustrated a partial cross-section of a bone covered with skin and soft tissues with the locking nail inserted into the bone and a perspective view of the aligned targeting guide in place with the present invention scalpel instrument inserted through a targeting guide tunnel and the blades in the retracted concave V-shape open-scissors position, also illustrating that a convex V-shape soft-tissue tunnel has been made from the previous steps; 
         FIG. 13  is an illustration of the preferred embodiment of the present invention scalpel instrument in use in the method of the present invention, wherein the blades of the scalpel instrument are in the concave V-shape open-scissors formation, and the scalpel instrument has traversed the wider soft-tissue tunnel path created by the present invention scalpel when it was in the convex V-shape formation, and has now reached the bone; the two sharp tips of the blades have penetrated the deep fascia and have come to rest against the bone; the incision in the deep fascia has a length equal to the diameter of the drill guide, and not the width of the deployed scalpel blades, and is smaller than the skin and soft-tissue tunnel; 
         FIG. 14  is a detail illustration, not to scale, of the next step after  FIG. 13 , of the preferred embodiment of the present invention scalpel instrument in use in the method of the present invention, wherein the blades of the scalpel instrument are in the concave V-shape open-scissors formation, and the scalpel instrument is being withdrawn; the first arm of the cruciate incision has been made by a scissoring action of the present invention scalpel invention, the incision in the deep fascia is narrower than the width of the skin and soft-tissue tunnel; 
         FIG. 14A  is a detail illustration, not to scale, of the first step in making a cruciate incision in the deep fascia, the two blades of the present invention scalpel instrument have punctured the deep fascia in the concave V-shape position; 
         FIG. 14B  is a detail illustration, not to scale, of the incision in the deep fascia after the present invention scalpel instrument has punctured the deep fascia in the concave V-shape position with the two blades having moved toward each other in a scissors-action and have completed the first arm of the cruciate incision in the deep fascia; 
         FIG. 14C  is a detail illustration, not to scale, of completing the cruciate incision in the deep fascia after the present invention scalpel instrument has punctured the deep fascia in the concave V-shape position and by scissors-action having completed one arm of the cruciate incision in the deep fascia, the scalpel instrument then partly withdrawn and rotated 90 degrees and then advanced toward the bone to penetrate the deep fascia a second time in the concave V-shape position; 
         FIG. 14D  is a detail illustration, not to scale, of the next step in the method, illustrating the preferred embodiment of the present invention scalpel instrument being withdrawn from the cruciate incision, after completing the second arm of the cruciate incision by a scissors action, thus making a cruciate incision in the deep fascia with two equal arms, an incision large enough to allow passage of the bullet-nosed leading end of the drill guide to pass through the deep fascia and down to the surface of the bone as seen in  FIGS. 14E and 14F , thereby allowing full access to the bone and the future placement of a screw unimpeded and without further damage to the soft-tissue, through the most minimal incision that could be made to accommodate the bullet nose of the drill guide; 
         FIG. 14E  is a detail illustration not to scale, illustrating the bullet-nosed drill guide having passed through the targeting guide tunnel, having passed through the soft tissue tunnel in the skin and soft tissues and about to pass through the cruciate incision in the deep fascia; 
         FIG. 14F  is the next step in the method, illustrating the bullet-nosed drill guide having passed through the cruciate incision in the deep fascia and against the bone, in readiness for the drill to pass through the drill guide and drill a hole through the bone for placement of a screw into the bone; 
         FIG. 15  is an illustration, not to scale, of a partial cross-section of a bone covered with skin and soft tissues with the locking nail inserted into the bone and a perspective view of the aligned targeting guide in place with the present invention scalpel instrument inserted through a targeting guide tunnel in the step after  FIG. 14  and scalpel instrument removed from the skin and soft-tissue, and leaving a perfectly aligned tunnel in the skin and soft tissues; 
         FIG. 16  is an illustration, not to scale, of a partial cross-section of a bone covered with skin and soft tissues with the locking nail inserted into the bone and a perspective view of the aligned targeting guide in place with the screw guide sleeve inserted through the opening in the skin and soft tissues left by the present invention and a screw driver inserting an affixing screw which passes through an opening in the locking nail within the bone; and 
         FIG. 17  is an illustration of the bone after the use of the method and apparatus of the present invention has been utilized and two screws are properly and precisely affixed at the correct angles to the bone, and through holes in the locking nail. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Although specific embodiments of the present invention will now be described with reference to the drawings, it should be understood that such embodiments are by way of example only and merely illustrative of but a small number of the many possible specific embodiments which can represent applications of the principles of the present invention. Various changes and modifications obvious to one skilled in the art to which the present invention pertains are deemed to be within the spirit, scope and contemplation of the present invention. 
     In  FIGS. 1 and 2 , there is shown a preferred embodiment of the present invention scalpel instrument  10 . The scalpel instrument  10  preferably has two blades  20  and  30 , but may have one or more. The scalpel instrument  10  has a long barrel  40 , having a length L 1 ″ that is long enough to traverse the length of a targeting guide tunnel and further extend through the skin and soft-tissue of a patient to the patient&#39;s bone. It has been found that the preferable length L 1 ″ of the barrel  40  is nine and a half inches to meet most current requirements, however the length of the barrel  40  may be whatever length is surgically required. The diameter D 1  of the barrel  40  is preferably the same as the inner diameter of the targeting guide tunnel  116 A,  116 B,  116 C,  116 D,  116 E etc. as illustrated in  FIG. 5 . As targeting guide tunnels come in different diameters, the scalpel instrument  10  of the present invention may come in corresponding diameters. Additionally, it is preferable that the barrel  40  of the present invention scalpel be shaped as a circular cylinder, but may also be of any shape, such as triangular, rectangular, octagonal, and so on, as long as the outer diameter D 1  of the barrel  40  fits snugly within the inner diameter of the targeting guide tunnel. 
     The scalpel instrument  10  also has two blades  20 ,  30 . While the scalpel instrument  10  may have any number of blades, the preferred embodiment is shown with two blades  20  and  30 . In the default position, the two blades  20  and  30  lay one atop the other with their cutting edges facing the centerline, as best illustrated in  FIGS. 3 and 4A . 
     The blades  20  and  30  are expanded and retracted by a retraction means  50 . The retraction means  50  may be of any form, but are here shown as a spring-loaded plunger  52  with a finger hold  70  and  72  located near the proximal end  64  of a plunger rod  60  and may or may not have a transverse rod  66  located at the tip of the distal end  62 . The preferred embodiment utilizes a transverse rod  66 , but the objectives of the present invention may be fulfilled by other means such as just the distal tip of the plunger rod  60 . If the retraction means  50  is of a spring-loaded plunger  52 , the spring  54  may be located anywhere on the apparatus as is useful and required to perform the objectives of the present invention. The two blades  20  and  30  have matching slots  22  and  32  respectively that are identical to each other when the blades  20  and  30  are placed flat one over the other facing the same direction, and are also at an angle to the direction of the plunger rod  60 , as shown in  FIG. 2  and  FIG. 3B . When the blades  20  and  30  are installed, the blades  20  and  30  are facing opposite directions, and therefore, the base of the two slots  22  and  32  are aligned, but the angles of the slots  22  and  32  are now going in opposite directions, as shown in  FIGS. 3 and 3B . The transverse rod  66  is engaged in the matching slots  22  and  32  of the respective blades  20  and  30 . The default position for the spring-loaded plunger  52  is in the retracted concave V-shape position, as shown in  FIG. 2  and detailed in  FIGS. 3 and 3B . This corresponds to the fully open position of the scissor blades,  20  and  30 . Placing two fingers, such as the first finger and second finger of a hand, into the finger holds  70  and  72 , the thumb is available to depress the cover  56  of spring-loaded plunger  52 . The thumb depresses the cover  56  and thereby depresses the spring-loaded plunger  52 , causing the spring  54  to compress and the plunger rod  60  to move forward up the barrel  40  of the shaft towards the distal end  42  of the barrel  40 . As the plunger rod  60  moves forward, the transverse rod  66  advances along the matching slots  22  and  32  until it reaches the ends  24  and  34  of the slots  22  and  32 . The transverse rod  66  has pushed both blades  20  and  30  simultaneously upward and because of the slots  22  and  32  of each blade  20  and  30  being oriented in opposite directions, the proximal ends of the two blades  20  and  30  angle outwardly and cross over each other as illustrated in  FIG. 3C , so that the proximal ends of the blades expand beyond the confines of the handle, while the pointed tips of the distal ends of the blades  20  and  30  move in corresponding opposite directions, and come together as a single, sharp point in a convex V-shape formation cutting surface of the present invention scalpel, as detailed in  FIGS. 3A and 4 , and shown in  FIG. 1 . The cutting edges are thus in the shape of a sharp-pointed, two-edged scalpel. A portion of the blades  20  and  30  resides within the barrel  40  of the scalpel instrument  10  at the distal end  42  of the barrel  40 . 
     The fully expanded position of the proximal ends of the blades simultaneously represents the fully closed position of the scissors ends of the blades as seen in  FIGS. 3A and 4 . The retraction, partial or full, involves the partial or full release of the retraction mechanism, which in the preferred embodiment entails the release of the spring-loaded plunger  52 , wherein the plunger rod  60  withdraws down the length L 1  of the barrel  40 , and the transverse rod  66  will correspondingly withdraw down the matching slots  22  and  32  to engage the aligned ends  26  and  36  of the matching slots  22  and  32  of the blades  20  and  30  causing the blades  20  and  30  to radially retract one over the other and further to withdraw down the barrel  40  of the scalpel instrument  10 . It should be noted that when the blades  20  and  30  are in full retraction position, the blades  20  and  30  are in concave V-shape or open-scissors formation, as detailed in  FIGS. 3 and 4A . The barrel  40  of the scalpel instrument  10  is long enough to reach the bone in this position. 
     When the cutting edge of the targeted scalpel forms a sharp pointed convex V-shape, as illustrated in  FIGS. 3A and 4 , if the scalpel is inserted straight down to the bone through the targeting guide tunnel, and then withdrawn straight out, without any sideways movements, the terminal end of the path made in this manner will be a triangular shaped space that will have the triangular dimensions of the triangular cutting edge, and the deepest part of the path created by the cutting edge will be a point. This will be of little consequence if the present invention scalpel instrument traverses only soft-tissues such as fat and muscle, since the drill guide can easily be advanced to the bone through such soft-tissue, and the objectives of the present invention will be achieved. However, the fascia lata and the iliotibial band lie against the bone and therefore, as soon as the advancing tip of the blade penetrates the deep fascia it will come up against the bone, and will be prevented from further advancement, and from making an adequate incision in the deep fascia, having made only a small puncture hole. 
     Although the drill guide has a conical leading end,  FIG. 14E , it will not pass through a small puncture hole. The surgeon may safely, easily and quickly overcome the thick deep fascia in the most precise and efficient manner by placing the mobile, two-bladed present invention scalpel instrument in a second cutting position,  FIG. 4A . The present invention scalpel instrument may have two blade positions, such that in the first blade position it is configured in a convex V-shape, sharp pointed, double-edged cutting surface with a single point as the leading edge, as shown in  FIG. 3A  and  FIG. 4 . A second blade position has two advancing points, which together form the shape of a concave V-shape, as illustrated in  FIG. 3  and  FIG. 4A . Additionally, the cutting edges of the blades face toward the centerline when they are in the concave V-shape position. In moving from the concave V-shape to the convex V-shape position, the blades cross over each other so that the cutting edges face away from the centerline in the convex V-shape position. As the blades move from the concave V-shape to the convex V-shape position and back again, activated by the surgeon through the spring-loaded plunger, they function as a surgical scissors as seen in  FIGS. 4A, 3C and 4 . 
     The surgeon will advance the blade the full distance from the skin to the bone in the first blade position as a convex V-shape until the present invention scalpel instrument&#39;s sharp tip touches bone. The present invention scalpel instrument is then withdrawn about one half inch, then is changed to the second blade position, the concave V-shape position, or open-scissors position, and again advanced towards the bone until the two sharp points of the concave V-shape penetrate the deep fascia. The surgeon then depresses the spring-loaded plunger causing the two center-facing cutting edges to move towards each other as surgical scissors, or as two independent slicing instruments, which now complete an incision between the two puncture points. Even then, as discussed before, this single incision will not be wide enough to allow passage of the cylindrical drill guide, because the single incision will only be as wide as the external diameter of the drill guide and in non-elastic tissue the incision needs to be 57% larger than the diameter of the drill guide. Therefore the present invention scalpel instrument, still in the second blade position, concave V-shape configuration, is again withdrawn about one half inch, rotated ninety degrees and again advanced to the bone until the two sharp points again penetrate the deep fascia. Using the scissors-function, a second fascial incision is made at 90 degrees to the first incision, thus creating a cruciate incision. The two arms of the cruciate incision are each only as long as the external diameter of the drill guide, but in the cruciate configuration, the two together create a larger opening in the fascia. In the inelastic fascia such a cruciate incision will still not allow passage of the full drill guide. Fortunately the drill guide has a conical nose, which will easily pass through this smaller cruciate fascial incision. 
     The present invention method and the present invention scalpel apparatus now have made it fairly easy to advance the bullet-nosed drill guide through this minimal cruciate opening in the deep fascia as seen in  FIGS. 14E and 14F . The cruciate incision in the deep fascia, with each of its two arms equal in length to the diameter of the drill guide is therefore the smallest incision possible to accommodate the instruments. 
     The scalpel instrument described here is unique in that it is two instruments in one: a surgical scissors and a double-edged, sharp pointed surgical scalpel. In the fully retracted position as seen in  FIG. 4A , the blades are an open-scissors with the sharp blade-edges facing the centerline. Moving from the retracted position  FIG. 4A  to the deployed position,  FIG. 3A  the sharp edges of the two blades move toward each other in a scissoring action. The blades cross over each other,  FIG. 3C , so that in the fully deployed blade position,  FIG. 3A , the two cutting edges face away from the centerline, forming a sharp pointed scalpel, with sharp, side-cutting edges, functioning usefully to puncture the skin, and make an incision as wide as the deployed cutting surface. As the blades move from the contracted to the deployed position and back again with the cutting surfaces facing each other, they usefully function as a surgical scissors. The deep fascia is first pierced by a forward thrusting motion of the two sharp pointed blades in the concave V-shape position or open-scissors position, seen in  FIG. 4A , and the first “arm” of the cruciate incision is then completed by the scissoring action of the blades by the two cutting edges moving towards each other. The present invention scalpel instrument is partially withdrawn, rotated 90 degrees, again advanced toward the bone, the two sharp points again penetrate the deep fascia, and the second “arm” is completed by a scissoring action, thus completing the cruciate cut. 
     The advantages of the present invention method and apparatus are numerous. By making an incision through the skin and soft-tissues with the present invention method and scalpel instrument, the surgeon makes a minimal incision quickly and accurately. The skin incision and soft-tissue path will be precisely the correct width needed for passage of the drill guide and other instruments, the incision through the deep fascia will be slightly smaller but adequate for the passage of the bullet-nosed drill guide, damage to the fascia lata, iliotibial band and other soft-tissues will be minimized, bleeding will be decreased, the time to make the incision will be shorter, the time taken to close each wound will be shorter, the time under anesthesia will be shortened, and the resulting scar will be more cosmetic. 
     The surgical scalpel of the present invention is tunnel guided through human or animal skin and soft tissues to its destination at the surface of any underlying bone. This requires an adequate cutting surface that is thrust forward along the path of the knife. It is preferable for the soft-tissue tunnel to have the same width all along its length, from the skin incision to the bone. The present invention scalpel in the convex V-shape configuration creates such a tunnel from the skin to the fascia. However, the sharp-pointed blade only makes a puncture hole in the deep fascia. Then, by a scissor cutting method, a cruciate incision is made in the deep fascia that is smaller than the soft tissue tunnel, but sufficient for passage of the bullet nose of the drill guide. 
     It is a well-known fact that the slightest contact of a scalpel&#39;s cutting edge against any metal surface will immediately dull the sharpness of the cutting edge. If a scalpel is used that has an advancing edge in a convex V-shape configuration, that is with its blades facing away from the center line of the blade, in passing the tunnel guided knife through a metal tunnel guide there is great likelihood that some or all of the cutting surfaces will touch the sides of the metal targeting tunnel guide at least some point along its excursion, especially as the knife edge is being introduced into the opening of the targeting guide tunnel. The sharp cutting edges of a knife in the concave V-shape, where only the inner edges of the concave V-shape are sharp and the outer edges are dull will therefore be protected from any such metal-to-metal contact. 
     Additionally, since the sharp cutting edges of each of the multi-blade embodiments of the present invention face inwards, and the dull outer edges outward, there is less likelihood that operating room personnel will cut themselves on the blades. Additionally, since all the cutting surfaces face inwardly in the concave V-shape position, the cutting surfaces described here will only cut on forward thrusting, or on scissoring. Therefore the skin cannot be additionally, accidentally, cut on withdrawal of the instrument, even if this instrument is unintendedly rotated upon withdrawal. 
     Referring now to the  FIGS. 5 through 17 , there is shown the method  400  and apparatus  10  for making a precise and minimal skin and soft-tissue tunnel, and a minimal cruciate incision in the deep fascia. In  FIGS. 5, 6 and 7  there is shown an outrigger  110  to which a locking nail  130  is attached at a first end  112  of the outrigger  110  and a targeting device  114  is attached at a second end  118  of the outrigger  110 . A locking nail  130  is inserted into the bone  200 , usually through the base  210  of the bone  200 . The locking nail  130  has multiple screw holes  132 A,  132 B,  132 C,  132 D,  132 E, etc. through which a screw  140 , see  FIG. 16 , will be affixed, however once the locking nail  130  is inserted into the bone  200 , the screw holes  132 A,  132 B,  132 C,  132 D,  132 E cannot be seen. The targeting guide  114  has numerous holes, the targeting guide tunnels,  116 A,  116 B,  116 C,  116 D  116 E, etc. that align with the screw holes  132 A,  132 B,  132 C,  132 D,  132 E, etc of the locking nail  130 . The locking nail  130  and the targeting guide  114  are each removably affixed to the outrigger  110 , which, among other things, maintains the alignment of the screw holes  132 A,  132 B,  132 C,  132 D,  132 E, etc. of the locking nail  130  and the corresponding targeting guide tunnels  116 A.  116 B,  116 C,  116 D,  116 E, etc. of the targeting guide  114 . Once it has been determined which screw hole  132 A,  132 B,  132 C,  132 D,  132 E of the locking nail  130  should be engaged with a screw  140 , a targeting guide tunnel  116  is selected from hole  116 A,  116 B,  116 C,  116 D,  116 E, etc. which corresponds to a respective hole  132 A,  132 B,  132 C,  132 D and  132 E in the locking nail  130 . For purposes of illustration only, the targeting guide tunnel  116 B is now in position exactly where the screw hole  132 B of the locking nail  130  is located at the exact angle at which the screw  140  will be inserted and affixed to the locking nail  114 , and is now in position for the present invention scalpel  10  to create a soft-tissue tunnel  230 , followed by insertion of the screw  140 , and surgical closing procedures. 
       FIG. 7  is a partial cross-section of a bone  200  covered with skin and soft tissue  240  with the locking nail  130  inserted into the bone  200  and a perspective view of the aligned targeting guide  114  in place with the present invention scalpel instrument  10  inserted through a targeting guide tunnel  116 B in the targeting guide  114  and the blades  20  and  30  moved out of the scalpel  10  and about to enter the skin  240  with a convex V-shape point for the scalpel blades  20  and  30 . 
       FIGS. 8 and 9  are examples of prior art and limitations thereof when making an incision and soft-tissue tunnel. It can be seen that current methods of creating an incision and a soft-tissue tunnel, are performed crudely and unguidedly. The surgeon must present the scalpel to the skin at an angle because the scalpel cannot be brought perpendicular to the spot because the targeting device  114 , previously shown, is in the way. The surgeon must work around the targeting device  114 , which therefore means that the scalpel is presented at an angle that is not 90 degrees to the bone. It can be seen that an incision from this angle through the skin and soft-tissue to the bone, creates an initial incision that is not where a screw  140  will be presented for entrance and is not of the required size. Nor does it create a soft-tissue tunnel that follows the same path that the screw  140  will travel to the bone. Additionally, it can further be seen that the soft-tissue tunnel ends in a single point at the bone. Under current practice, in order to create a skin incision that is located where the screw  140  will be presented, the surgeon must wiggle the scalpel back and forth, in a free-hand manner, to create the initial incision. Additionally, the surgeon must continue to wiggle the scalpel back and forth as it passes through the soft-tissue, so as to create a soft-tissue tunnel that will allow the screw  140  to progress perpendicularly to the fascia, and further, once the scalpel has reached the fascia, the surgeon continues to wiggle the scalpel back and forth, slicing the fascia and scraping against the bone, so as to cut a an oversized, straight line path between the targeting guide tunnel and the point of screw insertion on the bone surface. All of this is performed free hand, without guidance, and with the surgeon guessing the approximate locations of where the scalpel blade is as compared to the tunnel that must be made. It can be seen that quite a bit of skin and soft-tissue is cut, far more than is necessary, to make an incision and soft-tissue tunnel for a screw  140 . Usually the surgeon makes a long, longitudinal incision in the deep fascia. If a cruciate incision is made the damage is doubled, as the surgeon performs the above procedure, partly withdraws the scalpel and performs the same procedure blind, entering the previous incision at an angle approximately ninety degrees to the first incision. It can be seen that the prior art is imprecise and creates a greater amount of damage to the patient than what is surgically necessary. 
       FIG. 10  is an illustration of the next step after  FIG. 7  wherein there is illustrated a cross-sectional view of the preferred embodiment of the present invention scalpel instrument  10  in use in the continuing method  400  of the present invention, wherein the blades  20  and  30  of the scalpel instrument  10  are in the convex V-shape formation and have advanced through the skin and soft-tissue  240  and reached the bone  200 . It can be seen that the skin incision and the soft-tissue tunnel  230  that is created by the present invention is wider than the handle barrel  40  of the scalpel instrument  10 , and is at an angle that is the exact path that the screw  140  will follow. It can be seen that the sharp convex V-shape tip of the cutting surface made by the two blades  20  and  30  has penetrated the deep fascia  801 , has come to rest against the bone  200 , through a small puncture hole, and is prevented from further penetration through the deep fascia  801 , by the bone  200 , leaving an insufficient pathway through the deep fascia  801  for the bullet-nosed end of the drill guide  802 , to pass through. 
       FIG. 11  is an illustration of the next step after  FIG. 10  wherein there is illustrated a cross-sectional view of the preferred embodiment of the present invention scalpel instrument  10  in use in the continuing method  400  of the present invention, wherein the blades  20  and  30  of the scalpel instrument  10  are in the convex V-shape formation, have reached the bone  200 , and are now being withdrawn. It can be seen that at this point the soft-tissue tunnel  230  ends in a convex V-shape formation, matching the shape of the blades  20  and  30  of the scalpel  10 , leaving an insufficient opening in the deep fascia  801 , for passage of the bullet-nosed tip of the drill guide  802 , to pass through. It is desirous that the soft-tissue tunnel  230  does not end with a point at the bone  200 . It will be seen that the next steps in the present invention method  400  will create a complete tunnel  230  that will have access to the bone  200 , and terminates in the cruciate incision in the deep fascia, and not merely the single point where the two blades  20  and  30  meet the bone  200 , as created in this step of the method  400  so far. 
       FIG. 12  is a partial cross-section of a bone  200  covered with skin and soft-tissue  240  with the locking nail  130  inserted into the bone  200  and a perspective view of the aligned targeting guide  114  in place with the present invention scalpel instrument  10  inserted through a targeting guide tunnel and the blades  20  and  30  moved into the concave V-shape or open-scissors configuration; also illustrating that the soft-tissue tunnel  230  is, at this step in the method  400 , a convex V-shape incision  242  that has been made in the skin and soft tissues  240 , and deep fascia  801 , from the previous steps. 
       FIG. 13  is a detail illustration of the next step in the method  400  after  FIG. 12 , wherein there is illustrated a cross-sectional view of the preferred embodiment of the present invention scalpel instrument  10  in use in the method  400  of the present invention wherein the blades  20  and  30  of the scalpel instrument  10  are in the concave V-shape or scissors formation and have traversed the path of the previously made soft-tissue tunnel  230 , the sharp tips of the blades  20  and  30  have penetrated the deep fascia  801 , reached the bone  200  and, using the scissors action of the blades  20  and  30 , are about to make a first incision in the deep fascia  801 . 
       FIG. 14  is an illustration of the next step in the method  400  after  FIG. 13 , wherein there is illustrated a cross-sectional view of the preferred embodiment of the present invention scalpel instrument  10  in use in the method  400  of the present invention, wherein the scalpel instrument  10  is in the concave V-shape or open-scissors formation, had previously reached the bone  200 ; had previously made a scissoring incision in the deep fascia  801 , and is now being withdrawn. It can now be seen that the soft-tissue tunnel  230  does not end in a convex V-shape incision  242 , which was created previously, but now ends in a straight-line incision  243 , the scalpel instrument  10  was then partly withdrawn and rotated 90 degrees and advanced toward the bone  200 , so that the sharp tips of the blades  20  and  30  of the present invention scalpel  10  have again penetrated the deep fascia creating a second incision in the deep fascia intersecting the first incision at 90 degrees thus creating a cruciate incision  803 , through the deep fascia  801 , which is slightly smaller than the soft tissue tunnel  230  but which will sufficiently allow passage of the bullet-nosed end of the drill guide  803 , to the surface of the bone  200  as seen in  FIG. 14E  an  14 F, thereby allowing full access to the bone  200 , and the future placement of a screw  140 , unimpeded and without further damage to the soft tissue  240 . 
       FIG. 14A  is a detail illustration of the first step in making a cruciate incision in the deep fascia; the two blades of present invention scalpel instrument have punctured the deep fascia in the concave V-shape position. 
       FIG. 14B  is a detail illustration of the incision in the deep fascia after the present invention scalpel instrument has punctured the deep fascia in the “M” position and the two blades have moved toward each other in a scissors-action and have completed the first arm of the cruciate incision in the deep fascia. 
       FIG. 14C  is a detail illustration of the cruciate incision in the deep fascia after the present invention scalpel instrument has punctured the deep fascia in the concave V-shape position and by scissors-action has completed one arm of the cruciate incision in the deep fascia; the scalpel instrument was then partly withdrawn and rotated 90 degrees and then advanced toward the bone to penetrate the deep fascia a second time in the concave V-shape position. 
       FIG. 14D  is a detail illustration of the next step in the method  400 , illustrating the preferred embodiment of the present invention scalpel instrument being withdrawn from the cruciate incision  803 , after completing the second arm of the cruciate incision by a scissors action. thus making a small cruciate incision in the deep fascia with two equal arms, the length of each arm equal to the diameter of the barrel of the scalpel device, the cruciate incision smaller than the soft tissue tunnel  242 , but large enough to allow passage of the bullet-nosed leading end of the drill guide  802  to pass through the deep fascia and down to the surface of the bone as seen in  FIGS. 14E and 14F , thereby allowing full access to the bone  200  and the future placement of a screw  140  unimpeded and without further damage to the soft-tissue  240 . 
       FIG. 14E  is the next step in the method  400 , illustrating the bullet-nosed drill guide  802  having passed through the targeting guide tunnel  116 B, having passed through the soft tissue tunnel in the skin and soft tissues  230 , and is about to pass through the cruciate incision  803 , in the deep fascia. 
       FIG. 14F  is the next step in the method  400 , illustrating the bullet-nosed drill guide  802  has passed through the cruciate incision  803 , in the deep fascia and is against the bone  200 , in readiness for the drill to pass through the drill guide  802 , and drill a hole through the bone  200  for placement of a screw  140 , into the bone  200 . 
       FIG. 15  is the next step in the method  400 , illustrating a partial cross-section of a bone  200  covered with skin and soft-tissue  240  with the locking nail  130  inserted into the bone  200  and a perspective view of the aligned targeting guide  114  in place with the present invention scalpel instrument  10  inserted through a targeting guide tunnel  116 B in the targeting guide  114  the blades  20  and  30 , in concave V-shape retracted formation, removed from the skin and soft-tissue  240 , thereby creating a soft-tissue tunnel  230  that ends in a straight-line incision  243  at the bone  200 . It can be seen that the soft-tissue tunnel  230  made by the present invention method  400  and apparatus  10 , is in exact alignment with the screw hole  132 B and the targeting guide tunnel  116 B. It can further be seen that the straight-line incision  243  of the soft-tissue tunnel has been made with minimal trauma and minimal damage to the soft-tissue and deep fascia  240 . It can further be seen that the soft-tissue tunnel  230  has not been made free hand, or by chance, but was carefully and precisely guided by the present invention method  400  using the present invention scalpel  10 . It can further be seen that the present invention method  400  and apparatus  10  creates a soft-tissue tunnel  230  far more quickly, and yet still exceedingly precisely, than prior art methods and scalpels. 
       FIG. 16  is the next step in the method  400 , illustrating a partial cross-section of a bone  200  covered with skin and soft-tissue  240  with the locking nail  130  inserted into the bone  200  and a perspective view of the aligned targeting guide  114  in place with the screw guide sleeve  220 , in the targeting guide tunnel  116 B. The scalpel  10  of the present invention has been removed from the targeting tunnel  116 B and the method  400  of the present invention continues by inserting the screw guide sleeve  220  into the skin and soft-tissue tunnel  230  that ends at the bone. When the screw guide sleeve  220  reaches the bone  200 , a screw  140  is guided through the screw guide sleeve  220  and surgically inserted with a screw driver  804  through the bone  200  and through a screw hole  132 B in the locking nail  130 , which corresponds with targeting guide tunnel  116 B. 
       FIG. 17  is the next step in the method  400 , illustrating the bone  200  after the use of the method  400  and apparatus  10  of the present invention has been utilized. It can be seen that the locking nail  130  remains in place in the bone  200  and that two screws  140 A,  140 B, have been properly and precisely affixed at the correct angles to the bone  200 . 
     Described even more broadly, the present invention is a scalpel, comprising: (a) one mobile blade configured in such a way that its narrowest dimension is the same as, or narrower than, the width of a scalpel barrel, while the widest dimension of the blade is sufficiently wider than the width of the barrel to make an incision in skin; (b) the blade is set in such a way that it does not protrude radially outside the profile of the scalpel barrel in the contracted position; and (c) the blade is designed to create an incision of a given width by protruding beyond the radius of the barrel by a mechanism that rotates the blade 90 degrees so that by rotating the blade 90 degrees after passage through a targeting guide tunnel, a wider dimension protrudes radially from the sides of the barrel, and thereby presents a cutting edge that is wider than the scalpel barrel. 
     Of course the present invention is not intended to be restricted to any particular form or arrangement, or any specific embodiment, or any specific use, disclosed herein, since the same may be modified in various particulars or relations without departing from the spirit or scope of the claimed invention herein above shown and described of which the apparatus or method shown is intended only for illustration and disclosure of an operative embodiment and not to show all of the various forms or modifications in which this invention might be embodied or operated.