Patent Publication Number: US-2007123876-A1

Title: Multiple purpose nail, nail assembly and associated method

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
      Cross-reference is made to the following applications: DEP5507 titled, “INTRAMEDULLARY NAIL,” DEP5606 titled, “INTRAMEDULLARY NAIL WITH OBLIQUE OPENINGS” and 5607 titled “MULTIPLE PURPOSE NAIL WITH OBLIQUE OPENINGS” filed concurrently herewith which are incorporated herein by reference.  
     TECHNICAL FIELD OF THE INVENTION  
      The present invention relates generally to the field of orthopaedics, and more particularly, to a device for securing a prosthetic component to bone for use in with orthopaedic trauma or orthopaedic joint products.  
     BACKGROUND OF THE INVENTION  
      The skeletal system includes many long bones that extend from the human torso. These long bones include the femur, fibula, tibia, humerus, radius and ulna. These long bones are particularly exposed to trauma from accidents, and, as such, often are fractured during a trauma and may be subject to complex devastating fractures.  
      Automobile accidents, for instance, are a common cause of trauma to long bones. In particular, the femur and tibia frequently fracture when the area around the knee is subjected to a frontal automobile accident.  
      Often the distal end or proximal portions of the long bone, for example the femur and the tibia, are fractured into several components and must be realigned. Mechanical devices, commonly in the forms of pins, plates, screws, nails, wires and external devices are commonly used to attach fractured long bones. The pins, plates, wires, nails and screws are typically made of a durable material compatible to the human body, for example titanium, stainless steel or cobalt chromium.  
      Fractures of the long bone are typically secured into position by at least one of three possible techniques or methods.  
      The first method is the use of intramedullary nails that are positioned in the intramedullary canal of those portions of the fractured bone.  
      A second method of repairing fractured bones is the use of internal bone plates that are positioned under the soft tissue and on the exterior of the bone which bridge the fractured portion of the bone.  
      Another method of securing fractured bones in position is the use of external fixators. These external fixators have at least two general categories. In one category, the fixator is generally linear with a first portion of the fixator to connect to a first fracture segment of the bone and a second fracture segment of the fixator to connect to the second fracture segment of the bone. A first series of bone screws or pins are first connected to the fixator and then into the first portion of the bone. Then, a second series of screws or pins are connected to the fixator and then to the second fracture segment of the bone, thereby securing the first fracture segment of the bone to the second fracture segment of the bone.  
      A second method of external fixation is through the use of a ring type fixator that uses a series of spaced-apart rings to secure the bone. For example, an upper ring and a lower ring are spaced apart by rods. A plurality of wires are placed through the long bone and are connected on each end of the long bone by the ring. The wires are then tensioned much as spokes in a bicycle are tightened, thereby providing for a rigid structure to support the first fracture segment portion of the bone. Similarly, a plurality of wires are positioned through the second fracture segment of the bone and are secured to and tensioned by the lower ring to provide a rigid fixation of the second fracture segment of the bone bridging the fracture site.  
      There are a variety of devices used to treat femoral fractures. Fractures of the neck, head or intertrochanter of the femur have been successfully treated with a variety of compression screw assemblies, which include generally a compression plate having a barrel member, a lag screw and a compressing screw. The compression plate is secured to the exterior of the femur and the barrel member is inserted into a predrilled hole in the direction of the femoral head.  
      The lag screw which has a threaded end and a smooth portion is inserted through the barrel member so that it extends across the break and into the femoral head. The threaded portion engages the femoral head. The compressing screw connects the lag screw to the plate. By adjusting the tension of the compressing screw the compression (reduction) of the fracture can be adjusted. The smooth portion of the lag screw must be free to slide through the barrel member to permit the adjustment of the compression screw.  
      Subtrochanteric and femoral shaft fractures have been treated with the help of intramedullary rods, which are inserted into the marrow canal of the femur to immobilize the femur parts involved in fractures. A single angled cross-nail or locking screw is inserted through the femur and the proximal end of the intramedullary rod. In some varieties, one or two screws may also be inserted through the femoral shaft and through the distal end of the intramedullary rod. The standard intramedullary rods have been successfully employed in treating fractures in lower portions of the femoral shaft.  
      The proximal femoral fractures, for example, those around the lesser trochanter, greater trochanter, and femoral neck have been successful treated with a variety of compression screw assemblies and intramedullary rods. The intramedullary rods are inserted into the narrow canal of the femur to immobilize the femur parts involved in the fracture. Typically, a single screw is inserted through the femur and the proximal end of the intramedullary rod. Alternatively, a second screw may be inserted through the femur and into the proximal end of the intramedullary rod to prevent rotation of, for example, the neck and head of the femur.  
      One of the earliest intramedullary devices introduced in the United States was the Grosse-Kempf nail manufactured by Howmedica Company of Rotherudge, N.J. The Grosse-Kempf nail includes a threaded hole in the intramedullary rod for receiving an interlocking screw. The fully threaded screw cannot slide in order to permit the compression found in typical compression screw assemblies.  
      Another prior art device is in the form of Zickel™ nail (U.S. Pat. No. 3,433,220). The Zickel™ nail is a solid intramedullary nail having a single proximal tri-flangle cross-nail, which is inserted into the direction of the femoral head. The solid cross-section does not permit the nail to be introduced over a guide rod. Thus, the nail is prevented from being used for comminuted and distal fractures of the femur because the closed surgical technique cannot be practiced. In addition, adequate compression cannot be achieved due to the requirement to lock the cross-nail.  
      Yet another prior art device is in the form of the Russell-Taylor™ interlocking nail manufactured by Richards Medical Company of Memphis, now Smith, Nephew, and Richards. The Russell-Taylor™ nail similarly requires a fully threaded locking screw and therefore does not permit sliding of the screw relative to the intramedullary rod.  
      Yet a further prior art device is in the form of the Gamma™ nail is manufactured by Stryker-Howmedica. The Gamma™ nail provides for sliding compression of the lag screw through the use of a smooth shaft. The Gamma™ nail stops rotation of the lag screw by means of a set screw through the proximal portion of the intramedullary nail.  
      A further prior art device in the form of the Ace Trochanteric™ nail manufactured by DePuy Orthopaedics, Inc. provides for means of stopping rotation of the femoral head in an unstable fracture pattern by the use of a second threaded screw in the femoral head. The lag screw is permitted to rotate freely within the nail.  
      To promote and facilitate proper healing of bones, which have been fractured and have been repaired with femoral nails, the stability of the femur fracture is necessary to facilitate proper healing. Current products provide for the use of screws to the plate in the nails and to engage bone. These screws are limited in their placement and often times cannot be placed in the best location to reach stable bone. The limited ability to place nails in an intramedullary canal limit the ability to properly secure the bone and to provide the stability necessary to facilitate proper healing of the fractured long bone.  
      The present invention is directed to alleviate at some of the aforementioned concerns with orthopaedic fasteners.  
     SUMMARY OF THE INVENTION  
      The present invention is in the form of an intramedullary nail that contains a series of holes that allow for locking screws to be placed in various positions. The intramedullary nail can be locked statically or dynamically with the use of a dynamization slot. The invention allows three separate screws to be placed through the nail at one time in two different planes. The ability to use multiple screws in multiple planes allows better stability to be achieved with the locking screws.  
      The nail design of the present invention provides for multiple screw fixations to be achieved in opposing planes for better fracture stabilization. In addition to using multiple planes, the screw creates a triangular geometry that aids in better axial and rotational stability.  
      The present invention provides for an intramedullary nail with one transverse hole, angulated crossing holes, and a static-dynamic slot for locking screw placement. The locking screws are placed through the nail in a combination that, if three screws are utilized, a (z) shape appears in the medial to lateral plane. When the three-screw construction is utilized, the added stability that is desired is accomplished. The screw configuration can be angulated so that a combination of one or two screws can be used depending on the fixation that is desired, based on a particular fracture pattern.  
      According to one embodiment of the present invention, there is provided an intramedullary nail for use in a medullary canal of a long bone. The nail includes a body defining a longitudinal axis and an external periphery of the body for fitting in the medullary canal of the long bone. The body has a first internal wall of the body defining a first opening through the body, the first opening defines a first opening centerline. The body has a second internal wall of the body defining a second opening through the body. The second opening defines a second opening centerline. The first opening centerline and the second opening centerline are oblique with respect to each other.  
      According to another embodiment of the present invention there is provided an intramedullary nail assembly for use in a medullary canal of a long bone. The nail assembly includes a nail defining a longitudinal axis and an external periphery of the nail for fitting in the medullary canal of the long bone. The nail has a first internal wall that defines first opening through the nail. This first opening defines first opening centerline. The nail has a second internal wall that defines second opening through the nail. This second opening defines second opening centerline. The first and second opening centerlines are oblique with respect to each other. The nail assembly also includes a first screw which is slidably fitted to the first opening and a second screw which is also slidably fitted to the second opening.  
      According to yet another embodiment of the present invention there is provided a method for performing trauma surgery on a long bone. The method includes the step of providing an intramedullary nail. The nail defines a longitudinal axis and an external periphery of the nail for fitting in the medullary canal of the long bone. The nail has a first internal wall, which defines the first opening through the nail. The first opening defines a first opening centerline. The nail has a second internal wall of the nail defining a second opening through the nail. The second opening defines a second opening centerline. The first opening centerline and the second opening centerline are oblique with respect to each other.  
      The method also includes the steps of positioning the nail at least partially in the medullary canal and providing a first screw for cooperation with the long bone and for slidable cooperation with the first opening in the nail. The method further includes the steps of inserting the first screw through the cortical wall of the lesser trochanter of the long bone and inserting the first screw through the first opening. The method also includes the steps of inserting the first screw through the cortical wall of the greater trochanter of the long bone and providing a second screw for cooperation with the long bone and for slidable cooperation with the second opening in the nail. The method further includes the steps of inserting the second screw through the cortical wall of the long bone, inserting the second screw through the second opening, and inserting the second screw through the cortical wall of the long bone.  
      According to another embodiment of the present invention, there is provided an intramedullary nail for use in a medullary canal of a long bone. The nail includes a body defining a longitudinal axis and an external periphery of the body for fitting in the medullary canal of the long bone. The body has a first internal wall of the body defining a first opening through the body. The first opening defines a first opening centerline. The body has a second internal wall of the body defining a second opening through the body. The second opening defines a second opening centerline. The first and second opening centerlines are oblique with respect to each other. The first opening centerline and/or the second opening centerline are transverse to the longitudinal axis of said body.  
      According to yet another embodiment of the present invention there is provided a kit for use in repairing a fracture in a long bone. The kit includes a nail adapted for implantation in a medullary canal of the long bone. The nail defines a longitudinal axis and an external periphery of the nail for fitting in the medullary canal of the long bone. The nail has a first internal wall, which defines a first opening through the nail. This first opening defines first opening centerline. The nail has a second internal wall, which defines a second opening through the nail. This second opening defines a second opening centerline. The first and second opening centerlines are oblique with respect to each other. The first and/or second opening centerlines are transverse to the longitudinal axis of the nail. The kit includes a first screw, which is adapted to be slidably fittable with the first opening and similarly a second screw which is adapted to be slidably fittable with the second opening.  
      According to another embodiment of the present invention there is provided a method for performing trauma surgery on a long bone. The method includes the step of providing an intramedullary nail. The nail defines a longitudinal axis and an external periphery of the nail for fitting in the medullary canal of the long bone. The nail has a first internal wall, which defines a first opening through the nail. This first opening defines the first opening centerline.  
      The nail has a second internal wall that defines a second opening through the nail. This second opening defines a second opening centerline. The first and second opening centerlines are oblique with respect to each other. At least one of the first or the second opening centerlines are transverse to the longitudinal axis of the nail. The method further includes the steps of positioning the nail at least partially in the medullary canal and providing a first screw for cooperation with the long bone and for slidable cooperation with the first opening in the nail. The method also includes the steps of inserting the first screw through the cortical wall of the lesser trochanter of the long bone and inserting the first screw through the first opening.  
      The method further includes the steps of inserting the first screw through the cortical wall of the greater trochanter of the long bone and providing a second screw for cooperation with the long bone and for slidable cooperation with the second opening in the nail. The method includes the step of inserting the second screw through the cortical wall of the long bone, inserting the second screw through the second opening, and inserting the second screw through the cortical wall of the long bone.  
      The technical advantages of the present invention include the ability to provide locking screws in various positions within the long bone. For example, according to one aspect of the present invention, an intramedullary nail for use in a medullary canal of a long bone is provided. The nail includes a body defining a longitudinal axis. The body has a first internal wall defining a first opening and a second internal wall defining a second opening. The first and second opening centerlines are oblique with respect to each other. Locking screws may be fitted in the first and second openings. Thus, the present invention provides for the ability to provide locking screws in various positions.  
      The technical advantages of the present invention further include the ability to allow two separate screws to be placed in one or two different planes. For example, according to another aspect of the present invention an intramedullary nail for use in the medullary canal of a long bone is provided. The nail includes a body defining a longitudinal axis. The body has a first wall defining a first opening and a second wall defining a second opening. The first and second openings are oblique with respect to each other. Each of the first and second openings may receive a screw. The longitudinal axis of the screws are thus oblique with respect to each other. Thus, the present invention provides for the ability to allow two separate screws to be placed in one or two different planes.  
      The technical advantages of the present invention further include the ability to allow for multiple screw fixations to be achieved in opposing planes for better fracture stabilization. For example, according to yet another aspect of the present invention, an intramedullary nail for use in a medullary canal of a long bone is provided. The nail includes a body having a first and second openings. The first and second openings are oblique with respect to each other. Each of the respective holes may serve to receive a screw. Thus, the present invention provides for multiple screw fixations to be achieved in opposing planes for better fracture stabilization.  
      The technical advantages of the present invention also include the ability to place screws in multiple planes to treat unstable femur fractures. For example, according to another aspect of the present invention, a intramedullary nail for use in a femur is provided. The nail includes a body having first and second holes. The first and second holes are oblique to each other or are in multiple planes. Thus, the present invention provides for the ability to provide a nail that can place screws in multiple planes to treat unstable femur fractures.  
      The technical advantages of the present invention include the ability to use three screws to provide for a triangular geometry that aids in better axial and rotational stability for the patient. For example, according to yet another aspect of the present invention, an intramedullary nail for use in the medullary canal of a long bone is provided. The nail includes a body. The body has a first, second and third hole. Each of the three holes is positioned such that they provide for a triangular geometry. Thus, the present invention provides for the use of three screws that provide a triangular geometry that aids in better axial and rotational stability.  
      The technical advantages of the present invention also include the ability to prevent trochanteric to trochanteric and femoral neck fixation with the same nail. For example, according to another aspect of the present invention, an intramedullary nail for use in the medullary canal of a long bone is provided. The nail includes a first transverse opening, a second spaced apart transverse opening, and an oblique opening. The transverse opening centerlines and the oblique centerlines are oblique with respect to each other. Thus, the present invention provides for trochanter to trochanter and femoral neck fixation within the same nail.  
      Other technical advantages of the present invention will be readily apparent to one skilled in the art from the following figures, descriptions and claims.  
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is a partial anterior/posterior view of a intramedullary nail assembly implanted in a patient in accordance with an embodiment of the present invention with a screw directed toward the neck, two transverse screws, and an opening for a fourth screw;  
       FIG. 1A  is a partial anterior/posterior view of a nail with a longitudinal groove in accordance with another embodiment of the present invention;  
       FIG. 2  is an anterior/posterior view of the intramedullary nail of the intramedullary nail assembly of  FIG. 1 ;  
       FIG. 3  is a medial/lateral view of the intramedullary nail of  FIG. 2 ;  
       FIG. 3A  is a cross section view of  FIG. 2  along the line  3 A- 3 A in the direction of the arrows;  
       FIG. 3B  is an enlarged partial medial/lateral view of  FIG. 3  showing the chamfer on the distal end of the nail in greater detail;  
       FIG. 3C  is an enlarged partial anterior/posterior view of the nail of  FIG. 3  showing the chamfer in greater detail;  
       FIG. 4  is an enlarged partial medial/lateral view of the proximal end of the intramedullary nail of  FIG. 2 ;  
       FIG. 4A  is an end view of  FIG. 4 ;  
       FIG. 5  is an enlarged partial anterior/posterior view of the proximal end of the intramedullary nail of  FIG. 2 ;  
       FIG. 6  is a cross sectional view of  FIG. 2  along the line  6 - 6  in the direction of the arrows;  
       FIG. 7  is a partial anterior/posterior view of the intramedullary nail assembly of  FIG. 1  implanted in a femur with a screw directed toward the neck and two transverse screws;  
       FIG. 8  is a partial anterior/posterior view of the intramedullary nail assembly of  FIG. 1  with two transverse screws;  
       FIG. 9  is a partial anterior/posterior view of the intramedullary nail assembly of  FIG. 1  with a screw directed toward the greater trochanter and two transverse screws;  
       FIG. 10  is a partial perspective view of the nail assembly of  FIG. 1  with a partially threaded screw extending from the lesser trochanteric to the greater trochanteric as well as with a transverse partially threaded screw to form a nail assembly according to another embodiment of the present invention;  
       FIG. 11  is a plan view of a cortical screw for use with the nail assembly of  FIG. 1 , for example as a transverse screw or a lesser trochanter to greater trochanter screw;  
       FIG. 12  is a plan view of a cancellous screw for use with the nail assembly of  FIG. 1 , for example as a femoral neck screw;  
       FIG. 12A  is a plan view of another cancellous screw for use with the nail assembly of  FIG. 1 , for example as a distal screw;  
       FIG. 13  is a partial anterior/posterior view of a intramedullary nail assembly implanted in a patient in accordance with another embodiment of the present invention with a cannulated screw directed toward the neck and two transverse screws;  
       FIG. 14  is a plan view of a lag screw for use in the intramedullary nail assembly of  FIG. 13 ;  
       FIG. 15  is a cross sectional view of the lag screw of  FIG. 14  along the line  15 - 15  in the direction of the arrows;  
       FIG. 16  is an enlarged partial view of the box type thread form for the lag screw of  FIG. 14 ;  
       FIG. 17  is a partial view of a standard thread form for an alternate lag screw for use with an alternate embodiment of the intramedullary nail assembly of the present invention;  
       FIG. 17A  is a partial view of a V-shaped thread form for an alternate lag screw for use with an alternate embodiment of the intramedullary nail assembly of the present invention;  
       FIG. 17B  is a partial view of a square-shaped thread form for an alternate lag screw for use with an alternate embodiment of the intramedullary nail assembly of the present invention;  
       FIG. 17C  is a partial view of a truncated V-shaped thread form for an alternate lag screw for use with an alternate embodiment of the intramedullary nail assembly of the present invention;  
       FIG. 17D  is a partial view of a reverse box thread form for an alternate lag screw for use with an alternate embodiment of the intramedullary nail assembly of the present invention;  
       FIG. 17E  is a partial view of yet another alternate thread for use with another alternate embodiment of the present invention;  
       FIG. 18  is a partial anterior/posterior view of a intramedullary nail assembly implanted in a patient in accordance with yet another embodiment of the present invention with a screw directed toward the neck and two transverse screws;  
       FIG. 19  is a partial medial/lateral view of the nail of the intramedullary nail assembly of  FIG. 18  showing the proximal portion of the nail in greater detail;  
       FIG. 20  is a partial anterior/posterior view of the intramedullary nail assembly of  FIG. 18  showing its use with only the two transverse screws, one being fully threaded and one being partially threaded;  
       FIG. 21  is a partial anterior/posterior view of a intramedullary nail assembly in accordance with another embodiment of the present invention with a partially threaded screw extending from the lesser trochanteric to the greater trochanteric as well as with a transverse partially threaded screw and with a transverse fully threaded screw to form the nail assembly;  
       FIG. 22  is a partial medial/lateral view of the nail of the intramedullary nail assembly of  FIG. 21  showing the proximal portion of the nail in greater detail;  
       FIG. 23  is a partial anterior/posterior view of the intramedullary nail assembly of  FIG. 21  in position in the femur showing its use with only one fully threaded screw extending from the lesser trochanteric to the greater trochanteric;  
       FIG. 24  is a partial anterior/posterior view of the intramedullary nail assembly of  FIG. 21  in position in the distal femur showing its use with use with only the two transverse screws, both being fully threaded;  
       FIG. 25  is an anterior/posterior view of the intramedullary nail assembly implanted in a patient in accordance with a further embodiment of the present invention with a nail adapted for entry in the lesser trochanter;  
       FIG. 26  is a medial/lateral view of the intramedullary nail assembly of  FIG. 25 ;  
       FIG. 26A  is an enlarged partial medial/lateral view of  FIG. 26  showing the chamfer of the distal end in greater detail;  
       FIG. 26B  is an enlarged partial anterior/posterior view of the chamfer in the distal end of the nail;  
       FIG. 27  is a partial anterior/posterior view of the intramedullary nail assembly of  FIG. 25  in position in the femur showing its use with only one fully threaded screw extending into the neck of the femur;  
       FIG. 28  is a plan view of a kit for use in performing trauma surgery in accordance with yet another embodiment of the present;  
       FIG. 29  is a flow diagram of a method of performing trauma surgery in accordance with yet another embodiment of the present; and  
       FIG. 30  is a flow diagram of another method of performing trauma surgery in accordance with another embodiment of the present invention. 
    
    
      Corresponding reference characters indicate corresponding parts throughout the several views. Like reference characters tend to indicate like parts throughout the several views.  
     DETAILED DESCRIPTION OF THE INVENTION  
      Embodiments of the present invention and the advantages thereof are best understood by referring to the following descriptions and drawings, wherein like numerals are used for like and corresponding parts of the drawings.  
      According to the present invention and referring now to  FIG. 1 , an intramedullary nail assembly  10  is shown. The intramedullary nail assembly  10  is for use in a medullary intramedullary canal  6  of a long bone  4 . The intramedullary canal assembly  10  includes an intramedullary nail  12 . The nail  12  defines a longitudinal axis  14  and an external periphery  16  of the intramedullary nail  12 . The external periphery  16  is sized for fitting within the intramedullary canal  6  of the long bone  4 . The nail  12  has a first internal wall  18 . First internal wall  18  defines a first opening  20  through the nail  12 . The first opening  20  defines a first opening centerline  22 . The nail  12  further has a second internal wall  24 . The second internal wall  24  defines a second opening  26  through the nail  12 . The second opening  26  defines a second opening centerline  28 . The first opening centerline  22  and the second opening centerline  28  are oblique with respect to each other. The intramedullary nail assembly  10  further includes a first screw  30 . The first screw  30  may be slidably fitted to the first opening  20 . The intramedullary nail assembly  10  also includes a second screw  32 . The second screw  32  may be slidably fitting to the second opening  26 .  
      The nail  12  may have any suitable shape capable of being inserted into the intramedullary canal  6  of the femur  4 . The intramedullary canal  6  may be solid or may, as is shown in  FIG. 1 , be cannulated or include a longitudinal opening  34 . The nail  12  may have any shape. It may, for simplicity, have a generally round or circular cross section. The nail  12  may have a uniform cross section or may, as is shown in  FIG. 1 , have a larger diameter in the condylar and, in particular, the proximal condylar area of the nail.  
      For example as shown in  FIG. 1  the nail  12  includes a proximal portion  36  and a distal portion  38 . The proximal portion  36  has a larger diameter DL while the distal portion  38  has a smaller diameter DS. The larger diameter DL of the proximal portion  36  serves to provide support for the screws located in the proximal portion  36  of the nail  12 .  
      As shown in  FIG. 1 , the nail  12  may further include a third internal wall  40  defining a third opening  42 . A third fastener  44  in the form of, for example, a screw may be fitted in the third opening  42 . The third opening  42  may define a third opening centerline  46 . The screws  30 ,  32  and  44  may be any type which are capable of cooperating with bone.  
      For example, the screws  30 ,  32  and  44  may be in the form of cancellous or cortical screws. The second opening  26  and the third opening  42  as shown in  FIG. 1  may be transverse. The second screw  32  and the third screw  44 , in that they fit in the transverse openings, are preferably cortical screws so that they can engage opposed cortical walls of the femur  4 .  
      For example, as shown in  FIG. 1 , the second screw  32  includes a threaded body  48  composed of cortical threads. The second screw  32  further includes a head  50 . The second screw  32  extends as shown in  FIG. 1  from the cortical wall  7  of the femur  4  across cancellous bone  8  through the second opening  26 , through the cancellous bone  8  and again into cortical wall  7 . The support of the second screw  32  by the opposed cortical wall  7  provides ample support for the second screw  32 . The head  50  of the second screw  32  rests against the outer surface of the cortical wall  7 .  
      Similarly the third screw  44  is preferably in the form of a cortical screw. The third screw  44  includes a cortical threaded body  52  and a head  54 . The cortical threaded body  52  passes from the cortical wall  7  through cancellous bone  8 , through the third opening  42 , through additional cancellous bone  8  and into the opposed cortical wall  7 . The head  54  of the third screw  44  rests against the cortical wall  7  of the femur  4 .  
      The first screw  30  may be a cancellous or a cortical screw. Since the first screw  30  passes into the neck of the femur and maybe used to secure a fracture in the head of the femur, the first screw  30  may be a cancellous screw. The first screw  30 , as is shown in  FIG. 1 , is in the form of a cancellous screw. The first screw  30  includes a threaded cancellous body  56  and a head  58 . The first screw  30  passes through cortical wall  7 , cancellous bone  8 , first opening  20 , and into additional cancellous bone  8 .  
      Referring now to  FIG. 1A , another embodiment of the present invention is shown as nail assembly  10 A, which includes nail  12 A. The nail  12 A has a shape somewhat different than the nail  12  of  FIG. 1 , in that nail  12 A of  FIG. 1A  includes a groove  34 A formed in the nail  12 A and serves the same general purpose as longitudinal opening  34  of the nail  12  of  FIG. 1 .  
      The nail  12  may, as shown in  FIG. 3  include a relief surface such as a flat surface for example a chamfer  47  for assisting in leading the curved nail  12  into the medullary canal of the long bone, for example the femur. It should be appreciated that the chamfer may have a surface that is not flat, for example arcuate, for example a portion of a sphere or a cylinder.  
      Referring now to  FIG. 3B , the chamfer  47  is shown in the medial/lateral view with chamfer  47  shown on the side of the distal tip opposed to the origin  70  of the curved portion of the nail  12 . The chamfer may be defined by angle θ 1  from the longitudinal periphery of the nail  12 . The chamfer may be further defined by chamfer length CL 1  from the distal end of the nail  12 .  
      Referring now to  FIG. 3 , the chamfer  47  is shown in the anterior/posterior view with chamfer  47  shown at distal tip. It should be appreciated that the tip may be larger or smaller than shown.  
      Referring now to  FIGS. 2 and 3 , the intramedullary nail  12  of the nail assembly  10  of  FIG. 1  is shown. The nail  12  includes the distal portion  38  and the proximal portion  36 . The distal portion is fully shown in  FIGS. 2 and 3 . The distal portion as shown in  FIG. 2  is cylindrical and defined by diameter DS. The anterior/posterior view of the nail  12  of  FIG. 2  is straight and extends along longitudinal axis  14 .  
      The nail  12  includes a series of holes or openings adjacent distal end  60  of the nail  12 . As can be seen in  FIGS. 2 and 3 , the end  60  has a generally tapered shape to assist in the insertion of the nail  12  into the medullary canal. The distal portion  38  of the nail  12  near the end  60  includes a plurality of holes or openings for securing the distal portion  38  of the nail  12  in the long bone or femur  4 .  
      For example, and as shown in  FIGS. 2 and 3 , the anterior/posterior view of the nail  12  of  FIG. 2  shows a first distal opening  62  and a second distal opening  64 . The distal openings  62  and  64  as shown in  FIG. 2  are transverse or perpendicular to longitudinal axis  14 .  
      Referring now to  FIG. 3 , the distal end  38  of the nail  12  may include additional holes near the end  60  of the nail  12 . For example, and as shown in  FIG. 3  the nail  12  includes a third distal opening  66  which is transverse to the longitudinal axis  14  of the nail  12  and a fourth distal opening  68  which is also transverse or perpendicular to the longitudinal axis  14  of the nail  12 . The cross section of the distal openings  62 ,  64 ,  66  and  68  may have any shape and for simplicity, and as shown in  FIGS. 2 and 3 , the nail openings may be circular in cross section. For example the distal openings  62 ,  64  and  66  are shown circular in cross section. The fourth distal opening  68  as shown in  FIG. 3  has an oval cross section.  
      Referring now to  FIG. 3 , the medial/lateral shape of the nail  12  conforms to the medullary canal of a femur. The medial/lateral plane of the femur is curved and, as such, the nail  12  is curved in the distal portion  38 . As shown in  FIG. 3  the distal portion  38  of the nail  12  has a bend along longitudinal axis  14  defined by radius R extending from origin  70 .  
      Referring to  FIG. 3 , the proximal portion  36  of the nail  12  may include a notch  72  for assisting in inserting the nail  12  and for orienting the nail  12 , as well as, a chamfer  74  for providing clearance for soft tissue in the anatomy.  
      Referring now to  FIG. 3A , the distal portion  38  of nail  12  has a hollow circular cross section. The first distal opening  62  may, as shown, be perpendicular to the third distal opening  66 . The central opening or cannula  34  is located in the nail  12 .  
      Referring now to  FIG. 4  and  FIG. 4A , the proximal portion  36  of the nail  12  may, as is shown in  FIGS. 4 and 4 A, further include a fourth proximal opening  76  defining a fourth opening centerline axis  78 . The fourth opening  76  like the first opening  20  is skewed or oblique with respect to the plane, which defined the second and third openings,  26  and  42 .  
      For example and as shown in  FIG. 4A , centerline  28  of the second opening  26  and the centerline  46  of third opening  42  define a first opening plane  80 . As shown in  FIG. 4A , the plane  80  is coplanar with longitudinal centerline  14  of the nail  12 . Centerline  22  of the first opening  20  defines a second plane  82  that intersects plane  80  at longitudinal axis  14  of the nail  12 .  
      Similarly, centerline  78  of the fourth opening  76  defines a third plane  84  that is positioned angularly from the first plane  80  and the second plane  82  and intersects the first plane  80  and the second plane  82  at longitudinal centerline  14 . By providing the first opening  20  and the second opening  26  at different planes than the second opening  26  and the third opening  42 , a plurality of screws can be placed in an intersecting arrangement within a nail  12 , simultaneously, by having them pass through different portions of the nail and not intersect or interfere with each other.  
      Referring now to  FIG. 5 , the longitudinal opening or cannula  34  of the nail  12  may include a counterbore  86  on which internal threads  88  may be formed. The internal threads  88  may cooperate with a threaded fastener (not shown), which may engage the screws to lock the screws in position in the nail.  
      Referring now to  FIG. 6 , distal portion  38  of the nail  12  near distal end  60  is shown in greater detail. As described earlier, the distal portion  38  of the nail  12  includes a series of openings, for example, as shown in  FIG. 6 , four spaced apart openings. Two of the openings are oriented in the medial/lateral plane and two of the openings are oriented in the anterior/posterior plane. These openings provide for distal fixation of the nail by fasteners.  
      The openings may be normal or perpendicular to longitudinal axis  14  of the nail  12 . For example, third opening  66  is normal or perpendicular to longitudinal axis  14 . The third opening  66  has a generally cylindrical shape. The fourth opening  68  is also perpendicular to the longitudinal axis  14  of the nail  12  except that the fourth opening  68  is oval. The openings in the nail may also be skewed or not perpendicular to the longitudinal opening  34 . For example, first opening  62  intersects the longitudinal axis at an acute angle α while the second opening  64  intersects the longitudinal axis at an acute angle β.  
      It should be appreciated that the distal openings  62 ,  64 ,  66  and  68  pass through both external walls of the cannulated nail  12 . It should also be appreciated that the four openings in the proximal portion  36  of the nail  12  likewise pass through both external walls of the cannulated nail  12 . For example, the first opening  20 , second opening  26 , third opening  42  and fourth opening  76  all have an opening on each of the exterior walls of the nail  12  such that the opening passes through both external walls of the nail  12 .  
      Referring now to  FIG. 7 , the nail assembly  10  of the present invention is shown for use with the greater to lesser trochanter attachment of the intramedullary nail. As shown in  FIG. 7 , the nail assembly  10  is shown installed in a left femur.  
      The nail assembly  10  includes the nail  12  as well as second screw  32  which is positioned in second opening  26  and third screw  44  which is positioned in third opening  42 . The nail assembly  10  as shown in  FIG. 7 , further includes fourth screw  90  which is positioned in fourth opening  76  and positioned along fourth opening centerline  78 .  
      According to the present invention, the fourth screw  90  may be installed in the nail  12  while the second screw  32  and the third screw  44  are installed in the same nail  12 . The ability to place the fourth screw  90  in the nail  12  while the second screw  32  and third screw  44  are also installed in the nail  12  is possible because the fourth screw  90  is positioned in a different plane than the second screw  32  and the third screw  44 .  
      For example, and referring again to  FIG. 4A , the second opening  26  and the third opening  42  define first plane  80  while the fourth opening  76  defines the third plane  84 .  
      Referring again to  FIG. 7 , by positioning the fourth opening  76  and fourth screw  90  in a plane different from the second opening  26  and third opening  42 , the fourth screw  90  can be positioned as shown. The second screw  32 , third screw  44  and the fourth screw  90  form a z-shaped pattern which provides improved rigidity, strength and stability for the intramedullary nail assembly  10 .  
      The fourth screw  90  as shown in  FIG. 7  may be a cortical screw and may as shown in  FIG. 7  include a head  92  and a shaft  94  having cortical threads. The screw  90  is installed by passing it through cortical wall  7  through cancellous bone  8 , through the fourth opening  76  in the nail  12 , through additional cancellous bone  8 , and into the second cortical wall  7 . The head  92  of the screw  90  seats against the outer surface of the cortical wall  7  of the femur  4 .  
      Referring now to  FIG. 8 , yet another configuration for the nail assembly  10  of the present invention is shown. The nail assembly  10  of  FIG. 8  includes the nail  12  as well as second screw  32  which is positioned in opening  26  and third screw  44  which is positioned in third opening  42 . The nail assembly  10  as shown in  FIG. 8  may be used in both the right and left femur and may have the proximal portion  36  of the nail  12  positioned in the proximal condylar portion. The proximal portion  36  of the nail  12  may, alternatively, be positioned in the distal condyle of the femur. If the proximal portion  36  of the nail  12  is positioned in the distal condyle, the nail assembly  10  serves as a retrograde nail.  
      Referring now to the configuration as shown in  FIG. 9 , the nail assembly  10  is utilized on a right femur. When the nail assembly  10  of the present invention is used in a right femur, rather than a left femur, as shown in  FIG. 1  and  FIG. 7 , the function of the first opening  20  and the fourth opening  76  are reversed. For example, the nail assembly  10  of  FIG. 9  includes the nail  12  as well as second screw  32 , which is fitted in second opening  26  and third screw  44 , which is fitted in third opening  42 . The nail assembly  10  of  FIG. 9  further includes fourth screw  90 , which is fitted into first opening  20 . The fourth screw  90  is utilized to secure the greater trochanter  3  to the lesser trochanter  5  (see  FIG. 7 ).  
      Referring now to  FIG. 10 , second screw  32 , third screw  44  and fourth screw  90  are shown installed into the nail  12 . The configuration, as shown in  FIG. 10 , is the same as the configuration as shown in  FIG. 7 .  FIG. 10  illustrates the positioning of second screw  32  and fourth screw  90  in different planes. By providing the second screw  32  and the fourth screw  90  in different planes, the oblique screw  90  and the transverse screw  32 , as used as transverse screw  44 , may be installed at the same time.  
      Referring now to  FIG. 11 , a cortical screw for use with the nail assembly of the present invention is shown. The cortical screw as shown in  FIG. 7  may be used for example as third screw  44 . The third screw  44  has a length L 1 , a diameter DS and a pitch PS. The diameter DS is chosen to slidably fit in third opening  42 . The third screw  44  has a length L 1  such that the third screw  44  may have head  54  of the third screw  44  rests against cortical wall  7  of the femur  4  and extend through the third opening  42  and be secured in the opposed cortical wall  7  of the femur  4  (see  FIG. 7 ). The cortical screw  44  has a screw pitch PS, which is chosen to provide for optimum engaging strength for the screw  44  with the cortical bone.  
      The third screw  44 , as well as the second screw  32 , the first screw  30  and the fourth screw  90  may all be cortical screws. Preferably and as shown in  FIGS. 1 and 7  the third screw  44 , the second screw  32  and the fourth screw  90  are preferably cortical screws.  
      The second screw  32  as shown in dashed lines in  FIG. 11  has a length L 2  sufficient to permit the second screw  32  to have second screw head  50  rest upon the cortical wall of the femur and extend into a opposed cortical wall of the femur.  
      The fourth screw  90  is shown in phantom in  FIG. 11 . The fourth screw  90  is also a cortical screw and has a screw length L 3  sufficient to have the head  92  of the fourth screw  90  rest against the cortical wall of the femur and the opposed end of the cortical screw  90  extend into the opposed cortical wall of the femur. The second screw  32  and the fourth screw  90  may have a diameter sufficient to slidably fit into the second opening  26  and fourth opening  76 , respectively. The second screw  32  and the fourth screw  90  may have a pitch diameter PS identical to that of third screw  44 .  
      Referring now to  FIG. 12 , a cancellous screw is shown. The cancellous screw as shown in  FIG. 12  may be utilized in any of the openings of the nail assembly  10  of the present invention. The cancellous screw as shown in  FIG. 12  may be in the form of first screw  30  of the nail assembly  10  of  FIG. 1 . The cancellous screw  30  is designed to have the head  58  rest against the outer cortical wall of the femur and have a body  56  which includes cancellous threads which engage with cancellous bone. The cancellous screw  30  has a screw length CSL and a diameter DSL sufficient to slidably fit within the first opening  20  of the nail  12  (see  FIG. 1 ). The cancellous screw  30  has a pitch PSL sufficient to engage the cancellous bone.  
      Referring now to  FIG. 12A , small cortical screw  96  is shown. The small cortical screw  96  may be fitted into any of the first opening  62 , second opening  64 , third opening  66  and fourth opening  68  of distal portion  38  of the nail  12  (see  FIG. 6 ). The small cortical screw  96  may include a head  98  for engagement with the outer cortical wall of the femur.  
      Referring now to  FIG. 13 , yet another embodiment of the present invention is shown as nail assembly  10 B. The nail assembly  10 B is similar to the nail assembly  10  of  FIGS. 1 through 12  except that the nail assembly  10 B includes a first screw  30 B that is adapted for sliding compression in first opening  20 B of nail  12 B. The screw  30 B may be larger than screw  30  of nail assembly  10  of  FIG. 1 . The opening  20 B of nail  12 B may thus be larger than opening  20  of nail  12  (see  FIG. 1 ). Since the first opening  20 B and fourth opening  76 B are both used with first screw  30 B and fourth screw  90 B depending on whether the nail  12 B is in the right or left femurs, the fourth opening  76 B and the first opening  20 B may have the same diameter.  
      The nail  12 B may include a proximal portion  36 B similar to the proximal portion  36  of the nail  12  of  FIG. 1 . The nail  12 B may further include a distal portion  38 B similar to the distal portion  38  of the nail  12  of  FIG. 1 . The distal portion  38 B may include a first opening  62 B, a second opening  64 B, a third opening  66 B, and a fourth opening  68 B. The openings in the distal portion  38 B may be similar or identical to the openings in the distal portion  38  of the nail  12  of  FIG. 1 .  
      Referring now to  FIG. 14 , the screw  30 B may further include a removal feature  31 B in the form of, for example, internal threads formed in the small counter bore  33 B formed in the longitudinal opening  41 B adjacent the second end  35 B of the screw  30 B. The screw  30 B may further include a large counter bore  37 B extending from the second end  35 B of the lag screw  30 B and concentric with the small counter bore  33 B as well as with the longitudinal opening  41 B.  
      Referring to  FIG. 14 , the screw  30 B may further include a plurality of threads  43 B formed on the shank periphery of shank  56 B of the screw  30 B. The threads  43 B may, as shown in  FIG. 14 , have a non-uniform cross-section, which is more fully described in U.S. patent application Ser. No. 11/168,737 incorporated here in its entirety.  
      Referring again to  FIG. 14 , the periphery  22 B of the shank  56 B of the screw  30 B includes a first portion  50 B into which the threads  43 B are formed. It should be appreciated that the first portion  50 B may extend along the longitudinal opening  34 B of the screw  30 B from the first end  39 B to second end  35 B of the screw  30 B. It should also be appreciated and, as is shown in  FIG. 14 , that the periphery  22 B may include a second portion  52 B. The second portion  52 B of periphery  22 B of the shank  56 B may define a smooth surface  62 B. As is shown in  FIG. 14 , the periphery  22 B of the shank  56 B may be generally cylindrical and defined by a diameter, for example, DS.  
      The screw  30 B as is shown in  FIG. 14 , is generally cylindrical and defined by a thread diameter D and an overall length L. The shank  56 B of the screw  30 B includes the first portion  50 B which include threads  43 B and the second portion  52 B having the smooth surface  62 B. The overall length L of the screw  30 B is divided into a thread TL and a smooth or unthreaded length UL. The thread length TL defines the first portion  50 B and the smooth length UL defines the second portion  52 B. The thread length TL may, for example, be a portion of, for example, 20-40% of the overall length L of the shank  56 B. It should be appreciated that the smooth length UL is preferably a sufficient length such that the second portion  52 B of the screw  30 B may be positioned in the opening  20 B of the intramedullary nail  12 B (see  FIG. 13 ) to permit compression of the bone fracture of the femur.  
      The threads  43 , as is shown in  FIG. 14 , may advance spirally around the periphery  22 B of the shank  56 B of the screw  30 B. The threads  43 B may be defined by a pitch P defining a spacing along longitudinal opening  34 B between adjacent threads. The threads  43 B may advance spirally around the longitudinal opening  34 B in either a right or a left hand spiral configuration. The threads may, as is shown in  FIG. 14 , be of a single lead type but may alternatively be double lead configuration or a triple lead configuration.  
      Referring now to  FIG. 15 , the threads  43 B may have any suitable shape or thread form. For example and as shown in  FIG. 15 , the threads  43 B may have a combination box and tapered configuration. For example and is shown in  FIG. 15 , the threads  43 B may have any suitable shape or profile  58 B. For example, and is shown in  FIG. 15 , the profile  58 B may include a crest  60 B and opposed root  62 B. A trailing surface  64 B is positioned between the crest  60 B and the root  62 B adjacent the second end  45 B of the screw  30 B while the leading edge  66 B is positioned between the crest  60 B and root  62 B adjacent the first end  35 B of the screw  30 B.  
      As shown in  FIG. 15 , the leading edge  66 B and the trailing edge  64 B may be configured to provide for less force to assemble in the direction of arrow  68 B than to disassemble in the direction opposed to arrow  68 B. Such ease of assembly and difficulty in disassembly may be accomplished as is shown in  FIG. 15  by providing the trailing edge  64 B with a configuration that is normal or perpendicular to the root  62 B and the crest  60 B while providing the leading edge  66 B with chamfered or angled surface or, as is shown in  FIG. 15 , or with a partially angled surface between the crest  60 B and the root  62 B.  
      Referring now to  FIG. 16 , the threads  43 B are shown in greater detail. The threads  43 B of the screw  30 B may, as is shown in  FIG. 16 , include the leading edge  66 B such that the leading edge  66 B includes normal or perpendicular portion  70 B as well as an angled portion  72 B. The angled portion  72 B provides for reduced force to assemble the screw  30 B into the long bone or femur  4 . The perpendicular portion  70 B and the angled portion  72 B may define an angle αα therebetween. To minimize stress, the crest  60 B, the root  62 B, trailing edge  64 B, and leading edge  66 B may include arcuate portions therebetween to minimize the stress.  
      Referring now to  FIG. 17-17E , an alternative profile configuration for threads of the screw of the nail of the present invention is shown. Referring now to  FIG. 17 , profile  58 C is shown which includes arcuate roots and crest. For example, and is shown in  FIG. 17 , the profile  58 C of the screw  30 C includes an arcuate crest  60 C to which the trailing angled surface  64 C extends. The leading edge  66 C extends likewise from the arcuate crest  60 C. The profile  58 C further includes an arcuate root  62 C, which connects with trailing surface  64 C and leading surface  66 C.  
      Referring now to  FIG. 17A , yet another profile for threads for the screw of the present invention is shown as screw  30 D includes threads  43 D having a profile  58 D which include generally v-shaped threads  43 D. The profile  58 D includes trailing surface  64 D and leading surface  66 D. The root  62 D and the crest  60 D, as shown in  FIG. 17A , are minimal.  
      Referring now to  FIG. 17B , yet another profile of threads for a screw according to the present invention is shown. For example and is shown in  FIG. 17B , the screw includes threads  43 E having a profile  58 E that is blocked or rectangular. The profile  58 E includes parallel and spaced apart root  62 E and crest  60 E. The profile  58 E includes a trailing surface  64 E, a spaced apart and parallel leading surface  66 E. The trailing surface  64 E and the leading surface  66 E are normal or perpendicular to the root  62 E and the crest  60 E.  
      Referring now to  FIG. 17C , yet another embodiment of a profile of threads for a screw according to the present invention is shown. The profile  58 F of threads  43 F of the screw  30 F has a generally truncated v-shape of a standard screw thread. The profile  58 F includes a flat crest  60 F and opposed angled trailing surfaces  64 F and leading surface  66 F. A root  62 F extends from the trailing surface  64 F and the leading surface  66 F.  
      Referring now to  FIG. 17D , yet another profile of threads of a screw is shown as profile  58 G. The screw  30 G includes threads  43 G having the profile  58 G. The profile  58 G includes a leading surface  66 G that is normal to a crest  60 G and a spaced apart parallel root  62 G. The profile  58 G further includes a trailing surface  64 G that is positioned at an angle between the roots  62 G and the crest  60 G.  
      According to the present invention and referring now to  FIG. 17E , yet another form of profile of the screw of the present invention. The screw  30 H of  FIG. 17E  include threads  43 H defining profile  58 H. The profile  58 H includes a spaced apart parallel crest  60 H and root  62 H. The profile  58 H include a trailing surface  64 H, which is normal to the root  62 H and the crest  60 H. The profile  58 H further includes a leading surface  66 H, which is positioned at angle between root  62 H and crest  60 H.  
      Referring now to  FIG. 18 , yet another embodiment of the present invention is shown as nail assembly  110 . Nail assembly  110  of  FIG. 18  is similar to the intramedullary nail assembly  10  of  FIG. 1  except that the nail assembly  110  of  FIG. 18  includes only three openings in proximal portion  136  of intramedullary nail  112 . The proximal portion  136  includes first opening  120  as well as second opening  126  and third opening  142 .  
      As shown in  FIG. 18 , the second opening  126  and third opening  142  are transverse. The second opening  126  has a generally circular cross section while the third opening  142  may have an oval shaped opening. The first opening  120  may be oblique or positioned at an angle such that it enters head  2  of the femur  4 . It should be appreciated that the third opening  142  is in a plane different than that of openings  120  and  126 .  
      Cortical screws may be placed in the second opening  126  and the third opening  142 . For example as shown in  FIG. 18 a  second screw  132  is slidably fitted to second opening  126  and a third screw  144  is slidably fitted to third aperture  142 . A first screw  130  is slidably fitted to first opening  120  and engages cancellous bone  8  in head  2  of the femur  4 . The nail  112  may include a chamfer  174  to provide clearance for the patella tendon when the nail  112  is used in a retrograde manner.  
      It should be appreciated that the nail  112  may be used both on the left femur as shown in  FIG. 18  as well as for the right femur. It should also be appreciated that the first opening  120  may be used for a greater trochanter to lesser trochanter securement of the nail  112  if the nail  112  is rotated approximately 180 degrees about intramedullary nail longitudinal axis  114 .  
      In order that the nails for the femur are built to mate with the anatomy of a femur, it should be appreciated that right and left hand intramedullary nails may be desired. It should further be appreciated that the femoral intramedullary nail  112  of  FIG. 18  while not well suited for a femoral nail for a right femur, the nail  112  may be suitable for use as a greater trochanter to lesser trochanter intramedullary nail for a left femur.  
      Referring now to  FIG. 19 , the first opening  120 , second opening  126  and third opening  142  are shown in the proximal portion  136  of the intramedullary nail  112 . Similarly as can be seen from  FIG. 4A , the second opening  126  and the third opening  142  form a first plane while the first opening  120  forms a second plane. The first plane and the second plane, as is shown in  FIG. 19 , pass through longitudinal axis or centerline  114  of the nail  112 .  
      Referring now to  FIG. 20 , the nail assembly  110  is shown for use in the right femur  4 . When used in the right femur  4 , the intramedullary nail  112  is used as a greater trochanter to lesser trochanter nail. For example, as is shown in  FIG. 20 , the intramedullary nail assembly  110  includes intramedullary nail  112  having second opening  126  for receiving second screw  132  as well as third opening  142  for receiving third screw  144 . The second screw  132  and the third screw  144  are transverse screws. The intramedullary nail  112  further includes the first opening  120  which receives fourth screw  190 , which passes from greater trochanter  3  to lesser trochanter  5 .  
      Referring now to  FIGS. 21, 22  and  23 , yet another embodiment of the present invention is shown as intramedullary nail assembly  210 . The intramedullary nail assembly  210  is similar to the intramedullary nail  110  of  FIGS. 18 through 20 . Nail assembly  210 , however, is designed for greater trochanter to lesser trochanter securement of the left femur and/or for neck securement of the right femur.  
      For example, and as shown in  FIG. 21 , the nail assembly  210  includes a nail  212 , which is symmetrical to nail  112  of  FIGS. 18 through 20 . The nail assembly  210  of  FIGS. 21 through 23  is adapted for greater trochanter to lesser trochanter securement of a left femur and neck securement of a right femur.  
      For example, and as shown in  FIG. 21 , the nail assembly  210  includes the nail  212 , which has a second opening  226  for receiving second screw  232  as well as third opening  242  for receiving third screw  244 . The second screw  232  and the third screw  244  are parallel and describe first plane  280 . Nail  212  further includes first opening  220  for receiving first screw  230 . The first opening  220  and longitudinal centerline  214  of the nail  212  define a second plane to  282 . The first plane  280  and the second plane  282  intersect each other at the longitudinal centerline  214 .  
      The second screw  232  extends from cortical wall  7  of femur  4  through cancellous bone  8 , through second opening  226 , through cancellous bone  8  and into cortical bone  7 . The third screw  244  extends from cortical bone  7 , through cancellous bone  8 , through third opening  242 , through cancellous bone  8 , and into cortical bone  7 . The first opening  220  extends from lesser trochanter  5  through cancellous bone  8  through first opening  220 , through cancellous bone  8  and into the greater trochanter  3 .  
      Referring now to  FIG. 22 , the proximal portion  236  of the nail  212  is shown in greater detail. The proximal portion  236  includes first opening  220 , second opening  226  and third opening  242 . The first opening  220  and the second opening  226  have a generally cylindrical cross section and the third opening  242  as shown in  FIG. 22  is also cylindrical.  
      Referring now to  FIG. 23 , the nail assembly  210  is shown for use as a neck securing nail assembly for use with the right femur  4 . The nail assembly  210  includes nail  212 , which includes a proximal portion  236 . The proximal portion  236  includes first opening  220 , second opening  226  and third opening  242 . The second screw  232  is slidably fitted into the second opening  226 . Third screw  244  is slidably fit into third opening  242 . First screw  230  is slidably fitted into first opening  220  and extends into head  2  of the femur  4 .  
      Referring now to  FIG. 24 , it should be appreciated that the nail assembly of the present invention may be used as a retrograde nail. For a retrograde femoral nail, the nail is inserted through the distal portion of the femur.  
      For example and as shown in  FIG. 24 , nail assembly  10  is shown assembled in the retrograde fashion on femur  4 . The nail assembly  10  as shown in  FIGS. 1 through 10 , includes the nail  12 , which is positioned in distal condylar portion  1  of the femur  4 . The distal condylar portion  1  of the femur  4  receives the proximal portion  36  of the nail  12 . The proximal portion  36  includes second opening  26  for receiving second screw  32 . The proximal portion  36  of the nail  12  further includes third opening  42  for receiving third screw  44 . The second screw  32  and the third screw  44  extend from one cortical wall  7  through the cancellous bone  8  and through the nail  12  to the opposite cancellous bone  8  and into the opposed cortical wall  7 .  
      Referring now to  FIGS. 25, 26  and  27 , yet another embodiment of the present invention is shown as nail assembly  310 . The nail assembly  310  is in the form of a trochanteric entry nail assembly. The trochanteric nail assembly  310  includes a nail  312  having a proximal portion  336  and a distal portion  338 . Unlike the nail  12  of  FIG. 1 , nail  312  is bent between the proximal portion  336  and the distal portion  338 . For example, as is shown in  FIG. 25 , the proximal portion  336  defines a proximal portion centerline  314  and the distal portion  338  defines a distal portion longitudinal centerline  315 . The proximal portion centerline  314  and the distal portion centerline  315  define an angle θ′ therebetween.  
      Referring now to  FIGS. 26 and 27 , the proximal portion  336  of the nail  312  includes a first opening  320  that extends obliquely through proximal centerline  314  and is used to receive neck or first screw  330 . The proximal portion  336  further includes a second opening  326  and a third opening  342 . The second and third openings  326  and  342  are for receiving transverse screws  332  and  344 , respectively. The nail  312  further includes a fourth opening  376  for receiving the lesser trochanter to greater trochanter nail.  
      The nail  312  may, as shown in  FIG. 26  include a relief surface such as a flat surface for example a chamfer  347  for assisting in leading the curved nail  312  into the medullary canal of the long bone, for example the femur. It should be appreciated that the chamfer may have a surface that is not flat, for example arcuate, for example a portion of a sphere or a cylinder.  
      Referring now to  FIG. 26A  the chamfer  347  is shown in the medial/lateral view with chamfer  347  shown on the side of the distal tip opposed to the origin of the curved portion of the nail  312 . The chamfer may be defined by angle θ 2  from the longitudinal periphery of the nail  312 . The chamfer may be further defined by chamfer length CL 2  from the distal end of the nail  312 .  
      Referring now to  FIG. 26B  the chamfer  347  is shown in the anterior/posterior view with chamfer  347  shown at distal tip. It should be appreciated that the tip may be larger or smaller than shown.  
      Referring now to  FIG. 27 , the intramedullary nail assembly  310  includes in addition to the intramedullary nail  312 , the first screw  330  for cooperation with first opening  320 . The first screw  330  extends into head  2  of the femur  4 . The nail assembly  310  further includes the second screw  332  for cooperation with the second opening  326 . The intramedullary nail  310  further includes the third screw  344  for slidably fitting in third aperture  342 . The nail  312  further includes fourth opening  376 . The fourth screw  390  can be used if the first screw  330  is removed.  
      Referring now to  FIG. 28 , yet another embodiment of the present invention is shown as kit  400  for performing trauma surgery. The kit  400  includes a nail  412  similar to nail  12  of  FIG. 1 . The kit  400  further includes a first screw  430  similar to the screw  30  of  FIG. 1 . The kit  400  further includes a second screw  432  similar to the screw  32  of  FIG. 1 . The kit  400  may also include additional screws. For example, the kit  400  may include a third screw  444  similar to the screw  44  of  FIG. 1 , as well as a fourth screw  490  similar to the screw  90  of  FIG. 9 . The kit  400  may further include distal screws. For example, the kit  400  may include distal screws  496  similar to the screw  96  of  FIG. 12A . The kit  400  may include four separate distal screws  496 . The kit  400  may further include a fully threaded cancellous screw  430 A as an alternate to the partially threaded screw  430 .  
      Referring now to  FIG. 29 , yet another embodiment of the present invention is shown as method  500  for performing trauma surgery. The method  500  may include a first step  502  of providing an intramedullary nail. The nail may define a longitudinal axis and an exterior periphery of the nail. The nail may be fitted into the medullary canal of the long nail, for example, a femur. The nail has a first internal wall of the nail defining a first opening through the nail. The first opening defines a first opening centerline. The nail has a second internal wall defining a second opening through the nail. The second opening defines a second opening centerline. The first opening centerline and the second opening centerline are oblique with respect to each other.  
      The method  500  further includes a second step  504  of positioning the nail at least partially in the canal. The method  500  further includes a third step  506  of providing a first screw for cooperation with the long bone or femur and for slidably cooperating with the first opening in the nail. The method  500  further includes a fourth step  508  of inserting the first screw through the cortical wall of the lesser trochanter of the long bone.  
      The method  500  further includes a fifth step  510  of inserting the first screw through the first opening. The method  500  further includes a sixth step  512  of inserting the first screw through the cortical wall of the greater trochanter of the long bone. The method further includes a seventh step  514  of providing a second screw for cooperation with the long bone and for slidable cooperation with the second opening in the nail. The method  500  further includes an eighth step  516  of inserting the second screw through the cortical wall of the long bone. The method further includes a ninth step  518  of inserting the second screw through the second opening. The method has a tenth step  520  of inserting the second screw through the cortical wall of the long bone.  
      Referring now to  FIG. 30 , yet another embodiment of the present invention is shown as method  600  for performing trauma surgery. The method  600  may include a first step  602  of providing an intramedullary nail. The nail defines a longitudinal axis and an external periphery for fitting in the medullary canal of the long bone. The nail has a first internal wall defining a first opening. The first opening defines a first opening centerline. The nail has a second internal wall defining a second opening. The second opening has a second opening centerline. The first opening centerline and the second opening centerline are oblique with respect to each other. At least one of the first opening centerline and the second opening centerline are transverse to the longitudinal axis of the nail. The method  600  may include a second step  604  of positioning the nail at least partially in the medullary canal and a third step  606  of providing a first screw for cooperation with the long bone and for sliding cooperation with the first opening in the nail. The method  600  may include a fourth step  608  of inserting the first screw through the cortical wall of the lesser trochanter of the long bone and a fifth step  610  of inserting the first screw through the first opening. The method may also include a sixth step  612  of inserting the first screw through the cortical wall of the greater trochanter of the long bone and a seventh step  614  of providing a second screw for cooperation with the long bone and for sliding cooperation with the second opening in the nail. The method may also include an eighth step  616  of inserting the second screw through the cortical wall of the long bone and a ninth step  618  of inserting the second screw through the second opening. The method may also include a tenth step  620  of inserting the second screw through the cortical wall of the long bone.  
      Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions, and alterations can be made therein without departing from the spirit and scope of the present invention as defined by the appended claims.