ES2360762T3 - DISTAL ADDRESS DEVICE. - Google Patents

Abstract

An addressing device (20) adapted to direct a transverse bore (16, 18) into a bone nail (10) comprising: an arm member (28) adapted to engage an end portion (24) of a bone nail , wherein the arm member comprises a pointing part (32) extending parallel to a longitudinal axis of the bone nail; an adjustable pointing device (36) mounted on the pointing part, the adjustable pointing device having a guide bore (88, 90) adapted to align with the transverse hole in the nail, the adjustable pointing device being mobile with respect to to the pointing part in a direction perpendicular to a plane containing the longitudinal axis of the nail and the central axis of the transverse bore; and an object indicator (200) mounted on the adjustable pointing device, the object indicator having a radiolucent body that includes first and second angled leg parts that form a vertex at a first end of each part, the first part having of leg radiopaque elements (210, 212, 214) separated in it.

Description

Background of the invention

In order to accurately block long intramedullary nails (i.e., those with distal fixation screws), the distal screws must be precisely aligned with the transverse holes in the nail. This blockage is complicated by the deflection of the nail during the introduction into the bone channel that changes the position of the transverse bore with respect to its static position. Normally the surgeon has been forced to do this manually with the help of an X-ray C-arm. A common problem in this procedure is that the instruments are "in the middle" since they are in the image plane of the C-arm. In addition, distal blockage is problematic since distal holes cannot be made accurately through soft tissue due to the anatomical shape of the femur and the resulting curvature of the nail (in this case, in the Z direction) that is in a plane perpendicular to a plane parallel to the frontal plane.

Intramedullary nails often provide two distal transverse openings or holes for distal locking. For distal block, a nail can offer three locking options for use, depending on the fracture pattern. To achieve this, a proximal round hole and a more distal elongated hole is provided. The distal block is recommended if the fracture is unstable, if rotational stability is required or if there is a wide disparity between the diameter of the nail and the femoral cavity.

The first possibility is to place a locking screw in the distal part of the elongated hole. This creates a dynamic locking mechanism, that is, the nail is allowed to move distally and requires only one screw. Alternatively, one screw can be placed in the distal part of the elongated hole and the other in the round hole. Thus a static nail block is achieved and the movement of the nail is prevented. However, if dynamization is required after a period of time, the screw, placed in the round hole, can be removed leaving only the screw at the distal end of the elongated hole. This procedure requires two screws. Finally, one screw can be placed in the round support and the other placed in the proximal part of the elongated hole. Again, a static blockage occurs and requires the placement of two screws.

Various techniques can be used to guide drilling and screw insertion through the distal holes. The manual technique described above, as well as addressing instruments such as those used in a straight focus of the imaging device described below.

The essential initial stage in distal addressing is to place the fluoroscope so that the circular distal hole in the nail appears perfectly round. Naturally, this display cannot be used with the elongated hole. If the round hole appears elliptical in the vertical or horizontal plane, the position of the fluoroscopic image must be properly adjusted. It is advised to correct the image on one plane at a time.

Once the image intensifier is correctly placed, the tip of a drill is placed in the center of the hole and a hole is drilled through the first crust that is a lateral cortex in a femur and the nail goes through the transverse drill until You feel the resistance of the second crust. The drill normally has a scale to measure the desired screw length.

Alternatively, a hole can be drilled through the second crust while viewing the image. The required screw length can then be read directly from the scale of the screw in the drill. If a tissue protection sleeve is used around the drill, it must be removed for measurement. It is also possible to measure the correct screw length using a manual screw gauge that can be coupled with the outer surface of the medial cortex when the nail is in the femur. This is done after drilling through the second crust by removing the drill and advancing the small screw gauge hook through the holes behind the medial cortex and reading the required length of the locking screw.

Normally the distal locking screw, which is usually a 5 mm screw, is inserted through the skin using a screwdriver. The screw head is carefully advanced until it is in direct contact with the cortex. Then any used addressing instrument is removed.

For example, WO-03 / 065.907-A1 discloses a radiolucent adjustable drill template for addressing locking screws in an intramedullary nail having proximal and distal holes, and is provided with the handle means to which the device is temporarily fixed. nail, the drill template comprising a guide rail that can be fixedly attached to a free end portion of the handle means and extending in a direction substantially parallel to the proximal end portion of the nail; a rod member that can slide slidingly in a translation within the guide rail and that has a distal end portion provided with an internal thread of an opening that passes through the end portion; a guide screw that can be turned manually mounted between end plates of a base member and that engages with the internal thread of the distal end part of the bar member, thereby allowing the bar member to perform a translational movement in the ventral-dorsal direction along the guide screw and a rotation movement in the varo-valgus direction around the guide screw; a locking plate housed in the groove and allowing the bar member to perform the rotational movement when the first thumb screw is loose, but avoiding the rotation movement when the first thumb screw is tightened, and a type plate disk mounted on a frame fixedly attached to an element of the base member and provided with at least one offset drill, the plate can be rotated inside the frame in an extension-bending direction and can be locked by means of a second screw of butterfly.

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More illustrative drill templates can be assembled for addressing locking screws in an intramedullary nail from US-5,433,720, EP-1,356,777-A2 and DE-202.11.806-U1.

Summary of the invention

The present invention is intended to make the location of the screws easier and more precise. A pointing or pointing arm is fixed to a known nail holding arm. In a preferred embodiment, a fixing bolt is used to hold a steering apparatus that includes the aiming arm in a hole in the nail holding arm. A jaw device with a manual locking mechanism can also be used to hold the addressing device in the nail holding arm. A radiolucent adjustment device (adjustable in the Z direction) is slid into the aiming arm by means of a pin inserted in a corresponding opening in the aiming or addressing arm and secured by rotating a lever. In the aiming arm there is a series of holes, each hole having a number corresponding to the respective nail lengths (and, thus, to the corresponding position of the distal holes in each nail).

A radiolucent object indicator, which is slid in a dovetail guide present in the adjustment device, is the system with which the exact position located at the level of the holes in the nail is found. This is preferably done using oblique X-rays. This placement is achieved by aligning two planes, which are placed one behind the other on the object indicator, in parallel with respect to the longitudinal axis of the nail. For this, the ribs of the object indicator, which are otherwise transparent to X-rays, have X-ray marks. In the foreground, there are stripes of rounded X-rays, such as dashed lines. In the background, straight (continuous line) uniform threads are used so that, in correct Z placement, in the X-ray image, only two pairs of lines are recognizable at a certain distance from each other (dashed-straight). The threads and stripes are not aligned in the Z direction (that is, the threads in a continuous line are preferably separated more than the dashed line thread so that each of the threads is located in a different plane in the Z direction).

X-ray images may appear, for example, as follows:

First, the X-ray arm C is aligned. The image is as shown below if the alignment angle is incorrect.

---------------------------------- (dashed line thread) –––––––––– ––––––––––– (continuous line thread)

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In this case, the C-arm is in the correct alignment (mid-lateral plane and x / y).

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Finally, the adjustment device is adjusted so that the hole is in position on the nail in the Z plane.

In a correct Z position, the drill position is outside the continuous line indicators and the Z position can then be readjusted with the help of the adjusting screw of the adjusting device until the continuous line threads engage with the central axis of the distal holes in the nail.

X-ray markers on radiolucent localization arms for object devices are known from US Pat. No. 6,036,696, as well as the manual entitled Gamma Long Nail R 2.0 Operating Technique P. 25 which includes illustrations. This oblique X-ray operative technique is also known in its fundamental characteristics from an article by Hans Granhead, A New Technique Of Distal Screw Insertion For Locked Nailing, Acta Orthop Scan 1998 69 (3): 320-321.

Advantageously, by means of the oblique C-arm procedure, freer access is achieved for the distal transverse drilling of the femur and thus the risks of drilling are minimized during an X-ray imaging study.

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In order to provide reproducible results with the addressing apparatus of the present invention, the adjustment device can be adjusted in the Z direction with an adjustment screw thread that has no clearance. This can be achieved by using a cover mounted on the main body of the adjustment device, an O-ring, whose thickness is slightly greater than the recess provided for it in the body of the adjustment device. The cover is pressed and the adjusting screw is screwed into the threads on the body, so that the elastic O-ring stretches the sides of the adjusting screw against the sides of the thread and eliminates the splice clearance.

The operator uses a template or a plastic guide plate in the readjustment of the desired placement in view of the type of lock, that is, static or dynamic position. For this, the corresponding template or guide plate (right or left nail) is placed in the adjustment device preferably using a click mechanism.

The instruments of the present invention are designed to facilitate minimally invasive surgery and reduce operating time (Q) to a minimum with the help of the use of new instrumentation and an optimized surgical technique.

The nails have a proximal diameter of 15.5 mm to help minimize the length of the incision required for minimally invasive surgery. However, they offer the same biomechanical strength and shear resistance. An important advantage of the instrument platform of the present invention is that the instruments are designed for a minimally invasive surgical technique and reduce the time in Q to a minimum. The instruments are easy to use and easy to clean and can be used with a variety of intramedullary nails.

The addressing device of the present invention offers the competitive advantages of minimizing fluoroscopy time, helping to avoid drilling errors and facilitating calibration for each type of Gamma3 long nail. The addressing device is mainly made of radiolucent carbon fiber material to overcome the problem of X-ray artifacts. This will help the surgeon achieve an accurate optimal surgical result.

As used herein when referring to bones or other parts of the body, the term "proximal" means closer to the heart and the term "distal" means further from the heart. The term "inferior" means towards the feet and the term "superior" means towards the head. The term "anterior" means towards the front or face and the term "posterior" means towards the rear of the body. The term "medial" means towards the midline of the body and the term "lateral" means away from the midline of the body.

The invention relates to an addressing device for addressing a transverse bore in a bone nail that includes an arm member coupled to an end part of a bone nail and a pointing part that is part of the extending arm member parallel to a longitudinal axis of the bone nail. There is an adjustable pointing device mounted on the pointing part, the adjustable device having a guide hole that can be aligned with the cross hole in the nail. The adjustable device can move with respect to the pointing part in a direction perpendicular to a plane containing the longitudinal axis of the nail and the central axis of the transverse bore. An object indicator is mounted on the adjustable pointing device. The object indicator has a radiolucent body that includes first and second separate parallel flat portions, each of which has a separate radiopaque element therein. The adjustable pointing device can move in a longitudinal direction along the part of the arm member that extends parallel to the bone nail. Preferably, the object indicator includes a pair of separate radiopaque elements in the first and second flat parts. The radiopaque elements in the first flat part are preferably separated closer to each other than the radiopaque elements in the second flat part. In the preferred embodiment, the first and second planar portions extend perpendicular to a plane containing the central axis of the transverse bore of the nail and containing a longitudinal axis of the nail adjacent to the transverse bore. The adjustable pointing device is made of a radiolucent material. The guide hole in the aiming device is formed in part by a radiopaque insole that has a hole therein aligned with the transverse drill of the nail, with the template removably mounted in the adjustable aiming device adjacent to the guide bore. The nail includes two transverse holes drilled along the longitudinal axis of the nail and the adjustable pointing device and the template have two holes capable of alignment with the two transverse holes of the nail. One of the transverse holes in the nail is elongated in the direction of the longitudinal axis of the nail. In the preferred embodiment, the pointing portion of the arm member includes a series of holes along the length thereof to receive a support pin that extends from the adjustable pointing device. The arm member preferably has a connector element at one end thereof opposite an end coupled with the bone nail, the connector being removably coupled to the aiming part. A method is provided for finding a transverse bore in an intramedullary nail that includes the introduction of an intramedullary nail having a transverse bore in a bone channel, the coupling of a steering arm in the intramedullary nail, the addressing arm having a part that extends parallel to a longitudinal axis of the nail, mounting an adjustment device having a transverse drill guide in a central axis of the bore and the longitudinal axis of the nail, the drill guide of the adjustment device being able to move in a perpendicular direction in the part of the addressing arm that extends parallel to the longitudinal axis of the nail, the adjustment device having an object indicator coupled thereto having two sets of parallel radiopaque elements therein, the two sets of elements being aligned Parallel radiopaque in an X-ray beam, and locating the transverse hole in e l nail by centering the transverse hole in the x-ray beam between the two sets of parallel radiopaque elements if necessary by moving the adjustment device. The distance between the first set of parallel radiopaque elements is less than the distance between the second set. Preferably, the first set of radiopaque elements are solid pins and the second set of radiopaque elements are a series of connected twisted elements. The location of the plane parallel to the frontal plane is achieved by placing solid pins in the series of connected elements connected in the same separation as in the object indicator. The first set of radiopaque elements are solid pins and the second set of radiopaque elements are a series of connected twisted elements.

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Preferably, a plane containing ends of the radiopaque elements of the first and second radiopaque element sets forms a non-zero angle with a plane containing the first set of parallel radiopaque elements and a plane containing the second set of radiopaque elements in parallel. A fracture fixation system is also provided for a long bone comprising: a bone nail having at least one transverse bore and preferably a pair of transverse boreholes. An arm member is coupled to an end portion of the bone nail, wherein the arm member comprises a pointing portion that extends parallel to a longitudinal axis of the bone nail. An adjustable pointing device is mounted on the pointing part. The adjustable pointing device has a guide drill that can be aligned with the cross hole in the nail. The adjustable pointing device can move with respect to the pointing part in a direction perpendicular to a plane containing the longitudinal axis of the nail and the central axis of the transverse bore. An object indicator is mounted on the adjustable pointing device, the object indicator having a radiolucent body that includes first and second separate flat parts, each of which has a separate radiopaque element therein.

Brief description of the drawings

Fig. 1 is an elevational view of a typical intramedullary fixation nail for the femur that has a pair of screws of distal bones that extend through the cortex of a long bone;

fig. 2 is an exploded isometric view of the addressing apparatus of a preferred embodiment of the present invention;

fig. 3 is the addressing apparatus of fig. 2 in the unlocked condition assembled with the nail of fig. 1 introduced into a femur;

fig. 4 is an isometric view of the addressing apparatus of fig. 3 in a locked condition;

fig. 5 is the addressing apparatus of fig. 4 just before receiving an adjustment device that is being mounted on it;

fig. 6 is the addressing apparatus of fig. 5 with the adjustment device mounted thereon including a protective sleeve of radiolucent tissue in the adjustment device;

fig. 7 is an exploded view of the adjustment device shown in figs. 5 and 6;

fig. 8 is an elevational view of a tissue protection sleeve guide template for use with a right femur;

fig. 9 is an enlarged view of a part of the adjustment device just before the template of fig. 8;

fig. 9A is an elevation view showing the adjustment device mounted at one end of the addressing apparatus with the holes in the guide template aligned with the holes in the bone nail with the adjustment device in an unlocked position;

fig. 10 is an identical view to fig. 9a with the adjustment device in a locked position;

fig. 11 is a partial elevational view showing the adjustment device before the holes in the guide template that is being aligned with the transverse holes in the bone nail in the Z direction;

fig. 12 shows an isometric view of the entire addressing apparatus including the adjustment device with a radiolucent tissue protection sleeve mounted thereon;

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fig. 13 shows a pair of long and short radiolucent trocars and a pair of radiolucent tissue protection sleeves to receive the long and short radiolucent trocars;

the figs. 14 and 14A are elevational views of a radiolucent trocar equipped with a radiopaque element at the tip of the trocar;

the figs. 15A, 15B and 15C are views of the distal ends of three bone nails, each of which has a pair of cross holes that show the position of a bone screw when dynamic block, secondary dynamization block or static block is desired;

fig. 16A and fig. 16B show the addressing apparatus of the present invention mounted on a bone nail inserted into the femur of a patient located in an X-ray machine with a C-arm that can be adjusted both in an x plane and parallel to a frontal plane of the body as in a Z direction that extends in a plane parallel to the sagittal plane of the body;

the figs. 17A to 17C show the alignment procedure of the radiolucent trocar of fig. 14 when mounted on the adjustment device to position a transverse bore in the nail when used in an x-ray beam approach;

fig. 18 is a partial isometric view of the addressing apparatus of the present invention including the adjustment device with a drill guide and blunt drill mounted thereon to drill a hole in the bone around the nail for insertion of a bone screw;

fig. 19 shows the introduction of a bone screw through a drilled bone and in a transverse drill of a bone nail using the addressing apparatus and the adjustment device of the present invention;

fig. 20 is an isometric view showing the introduction of a second bone screw through a pre-drilled hole in the bone to a second transverse bore of the bone nail;

fig. 21 shows the addressing apparatus of the present invention including an object indicator for use with an oblique X-ray beam approach before the indicator is coupled with the adjustment device of the present invention;

fig. 22 is an isometric view of the object indicator showing a separate pair of radiopaque wires in broken line mounted thereon in the same plane;

fig. 22A is an elevational view of the object indicator showing the pair of wires in a broken line extending in the same vertical and parallel plane;

fig. 22B is a cross-sectional view of the object indicator of fig. 22A along the B-B line rotated 90 ° showing the coplanar dashed strands at the top and a pair of solid radiopaque wires separated at the bottom;

fig. 23 is an isometric view showing the addressing apparatus of the present invention including the object indicator mounted on the adjustment device with an x-ray beam extending at an oblique angle thereto;

fig. 24 shows the lines in group A that would appear in a fluoroscope when the x-ray beam is not aligned with the XY plane of the nail cross-holes and in group B that show the alignment of the wires in the dashed line and the wires in line continue when the x-ray beam is aligned correctly;

fig. 25 shows the view in the fluoroscope when the center of the transverse bore is incorrectly aligned (group of wires A) and when the wires in the dashed and continuous line are correctly aligned around the center of the transverse bore (Group B);

fig. 26 shows a partial view of the addressing apparatus of the present invention that includes an adjustment device with the object indicator mounted therein adjusted in the Z direction to correctly align the holes and the guide template with the transverse holes in the bone nail ;

fig. 27 is a fluoroscopic image of the object indicators correctly aligned with the threads in a dashed and continuous line correctly aligned with the transverse bore in the bone nail;

fig. 28 is an isometric view of the assembly of the object apparatus that includes the adjustment device and the object indicator with a tissue protection sleeve mounted therein to guide a trocar and form an incision before drilling the bone for reception of a bone screw;

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fig. 29 is a view similar to fig. 20 showing the introduction of the second bone screw into a transverse bore of a bone nail after the bone has been blunted when the oblique approach is used;

fig. 30 is an isometric view of an alternative object indicator of the present invention having first and second legs oriented at an angle;

fig. 31 is an elevation view of the object indicator of fig. 30;

fig. 32 is an elevation view of the first leg of the object indicator shown in fig. 31 along lines 32-32 thereof;

fig. 33 is an elevation view of yet another embodiment of the object indicator of the present invention similar to that shown in fig. 30 but with the first and second legs connected by a pivoting hinge;

fig. 34 is an isometric view of the object indicator of fig. 30 mounted on an adjustment device similar to that shown in figs. 7 to 9;

fig. 35 is the addressing system of the present invention including the object indicator of fig. 30 in a simulated x-ray beam;

fig. 36 is a fluoroscopic view of a trocar that will align with a distal hole in a nail using the object indicator elements of fig. 32;

fig. 37 is an intermediate fluoroscopic view of the trocar and the nail being aligned; Y

fig. 38 is a fluoroscopic view showing the metal trocar in alignment with the distal nail hole of a bone nail.

Detailed description

Referring to fig. 1, a typical intramedullary nail 10 used for fracture fixation is shown as commercialized by Stryker Trauma GmbH as a GAMMA® long bone nail. The nail 10, when used in a femur 12 includes a screw screw 14 for insertion into the head of a femur and a pair of distal locking screws 17 that pass through the hole 16 and the elongated hole 18, which couple the cortical bone on the lateral and medial sides of the distal femur 15.

Referring to fig. 2, a partially assembled addressing apparatus of the present invention denoted generally as 20 is shown, which includes a handle portion 22 coupled with the proximal end 24 of the femoral intramedullary nail 10. The handle 22 can be coupled by means of a threaded joint to a proximal end 24 of the nail 10 or in any other way that is well known in the art. In a preferred embodiment, the handle 22 includes a coupling part 26, which is adapted to receive several addressing devices to find and drill the bone for the reception of a femoral screw screw 14 and the distal bone screw holes 16 and 18. For example, said steering arm for a screw screw may be similar to those shown in US Pat. 6,039,739 and 7,077,847. As shown in fig. 2, the addressing apparatus 20 includes a distal addressing arm 28, which includes a mounting system 30 adapted to engage a portion 26 of the arm 22. The arm 26 is provided with a series of transverse holes 32 to receive a bolt of fixing 34. As will be discussed in more detail below, the distal steering arm 28 includes an adjustment device 36 mounted thereon.

Referring to fig. 3, a bone nail 10 inserted in a right femur 12 is shown with a coupling apparatus 30 inserted into a part 26 of the arm 22 just before introducing the fixing bolt 34 through one of the holes 32 in the part 26. To ensure correct rotation alignment between the coupling part 30 and the part 26 of the arm 22, a window 38 can be provided in the coupling part 30 to locate an alignment indicator formed in the part 26 (not shown). A lever 40 of a distal addressing arm may be provided, which is coupled to a locking member that fits into an internal bore of the part 26 so that when the lever 40 is rotated, a firm friction block develops between the handle part 26 and coupling part 30. This locking position is shown in fig. 4. Obviously, any coupling procedure of the steering arm 28 can be used to handle 22. It would even be possible to make the entire addressing apparatus in one piece. After the distal steering arm is mounted on the handle 22, it is located outside the body in alignment generally parallel with the longitudinal axis of the nail 18.

Referring to figs. 5 and 6, an adjustment device 36 is shown immediately prior to mounting on the distal steering arm 28. The adjustment device 36 is mounted on one of a series of holes 42 on the distal steering arm 28. Each of The holes 42 locates the adjustment device 36 in correct alignment for one of a series of different longitudinal bone nails. Obviously, the shorter the nail, a drill 42 is used closer to the proximal end of the nail 10. When mounted in the hole 42 suitable for a nail of a given length, the adjustment device is in alignment with the cross holes 16 and 18 at the distal end of the nail 10. It should be noted that the arm 28 and the adjustment device 36 are made of a radiolucent material such as PEEK (polyether ether ketone).

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Referring to fig. 7 shows an exploded view of the adjustment device 36. The device 36 includes a pair of adjustable members 50 and 52 that can be moved up and down into a cavity 54 in a body 56 of the device 36. A coupling pin 58 it extends through members 50 and 52 and therefore moves vertically inside the cavity 54 with the actuation of an adjustment screw 60. The pin 58 includes a pair of radially extending tabs 62 and 64, which are received inside of recesses with grooves 43, 45 that open to the holes 42 of the arm 28. (See Fig. 9A.) The tabs 62 and 64 prevent the rotation of the pin 58 after insertion into the hole 42. It is also mounted on the body 56 a pair of support pins 66 and 68, which are used to mount a template shown in fig. 8. A locking mechanism generally denoted by 70 is provided that is capable of blocking moving elements 50 and 52 and, therefore, pin 58 in a desired vertical position within cavity 54 of body 56. Thus, during assembly and when the pin 58 is mounted in the holes 42 of the adjustment arm 28, the body of the adjustment device 56 can be moved up and down in the Z direction by rotating the screw 60. In the preferred embodiment, the screw 60 is designed to have no slack so that precise adjustments can be made. This can be achieved with an O-ring 67 and a cover 69 that forces the O-ring against the rod 73 of the screw 60. The body 56 includes a pair of dovetail-shaped extensions 91, 92 on each side surface. When a desired position is reached, the locking mechanism 70 can be actuated by rotating the lever 71 to lock the body 56 with respect to the pin 58. Obviously, there are many other ways of designing the adjustment device. However, the essential thing is that the body of the adjusting device 56 can move relative to the pin 58, at least in the Z direction, after being mounted on the arm 28.

Referring to fig. 8, a right template 74 is shown for use with the adjustment device 36. The template 74 includes a pair of mounting openings 76 and 78 and a pair of holes 82 for use in locating the cross holes in the nail bone, guiding a drill to drill the cortical bone adjacent to the cross holes and to introduce bone screws into the cross holes. Although a template 74 for a right femur is shown, the template for the left femur would be similar with holes 80 and 82 ("dynamic" and "static") reversed. The "static" and "dynamic" marks refer to the position of the bone screws in circular holes 16 and elongated hole 18 as set forth below. The template 74 includes openings 76 and 78 for mounting the template on the pins 66 and 68 of the adjustment device 36. Since the template 74 is made of plastic, one way of providing a left and right template 74 is to mold the marks necessary for the right template on one side and the marks for the left template on the other side.

Referring to fig. 9, the right template 74 is shown just prior to mounting on pins 66 and 68 of the adjustment device. As can be seen in fig. 9, the pins 66 and 68 are generally cylindrical although they may have recessed parts 69 to receive upper flat surfaces 84 and 86 of opening 76 and 78. Thus, the template 74 is located on the pins 66 and 68 and then slides down in fig. 9 to lock the template 74 in the adjustment device. It should be noted that the adjusting device 36 has elongated holes 88 and 90 so that different separations between the holes 80 and 82 of the template 74 can be accommodated. This would be needed when secondary dynamization is required.

Fig. 9A shows the adjustment device 36 mounted on the arm 28 with the holes 80 and 82 aligned with the circular hole 16 and the proximal end of the elongated hole 18 of the nail 10. In the position shown in fig. 9A the locking system 70 is in the unlocked position. Referring to fig. 10, the lever 71 of the locking system 70 moves to the locked position thereby fixing the adjusting device 36 and the template 74 in the desired position. They are also shown in figs. 9A and 10 the pair of dovetail-shaped mounting elements 91 and 92 formed on the sides of the body 56 of the adjustment device 36. The function of these dovetail-shaped elements 91 and 92 will be discussed in more detail later.

Referring to fig. 11, in contrast to figs. 9A and 10, the adjustment device 36 is shown in an incorrect position in the Z direction, whereby the surgeon must adjust the position of the template by turning the screw 60 to thereby move the body 56 of the adjustment device 36 to Get the correct alignment. It should be noted that template 74 in fig. 11 in a left template has holes 80 and 82 located closer to each other than that shown in the right template 74 of fig. 8, which allows the bone screw to be inserted into the elongated hole 18 to be in the most proximal part of the elongated hole 18 while the template in fig. 8 has a wider separation so that the bone screw will be located at the most distal end of the elongated hole

18. The closest hole position in template 74 will produce a static lock if the template is a right or left template. It is best shown in fig. 15 in which the rightmost nail 100 shows that the bone screws are placed for static blocking in order to prevent the nail from moving distally within the medullary canal. The central nail 102 is referred to as secondary dynamization in which the nail can move distally if the bone screw in the round transverse bore 16 is removed. The dynamic locking is shown in the section of the nail 104 in which the nail can move distally around the single transverse locking screw in the elongated hole 18. The separation between the two screws is greater in the nail 102 with respect to the nail 100 of so that two different right and left 74 templates are required.

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Referring to fig. 12, the addressing apparatus is shown with the adjustment device 36 mounted thereon including a radiolucent tissue protection sleeve 106 mounted inside the hole 82 of the template 74. A tissue protection sleeve helps guide a trocar and a Drill in alignment with the transverse drill at the end of the distal nail 10 and protects the tissue when it is drilled through the cortical bone of the distal femur.

Referring to fig. 13, long and short radiolucent trocars 110 and 112, respectively, and long and short radiotransparent tissue protection sleeves, 114 and 116, respectively, are shown. The fabric protection sleeves 114 and 116 are tubular with a transverse bore to accommodate the standard radiolucent trocar for cutting tissue and a drill bit for drilling a hole in the cortical bone of the femur. Long and short trocars and sleeves are provided to accommodate patients of different sizes. However, the use of the short trocar is preferred since there will be a smaller angular error between the support in the adjusting device 36 and the end of the sleeve.

Referring to fig. 14, a long radiolucent trocar 110 is shown having a tip 118 that includes a radiopaque element 120 along its central axis 122. The short radiolucent trocar has the identical tip structure that includes a radiopaque object member 120. The radiolucent trocars they are used to direct the transverse holes in the nail as will be discussed later in relation to the straight x-ray beam approach. As discussed above, the short sleeve is preferred. The tissue protection sleeves 114 and 116 must be of sufficient length to come into contact with the cortical surface of the bone and thereby protect the tissue during the drilling operation.

Referring to figs. 16A and B, the use of an adjustable standard X-ray imaging device in a straight focus with the patient's leg inserted into the path of the X-ray beam is shown. The addressing apparatus 20 of the present invention is mounted in a nail that has been introduced into the medullary canal, in this case, of figs. 16A and 16B, the left femur. The figures show the movement of the imaging device to align the fluoroscope 124. The essential initial stage in distal addressing is to place the fluoroscope image so that the distal orifice 16 in the nail appears perfectly round. Naturally, this visualization stage refers to the appearance of the round hole and not the elongated hole 18. If the hole appears to be elliptical in the vertical or horizontal plane, the position of the image intensifier must be properly adjusted as shown in the schematic diagrams in figs. 16A and 16B. It is advised to correct the image on one plane at a time. The radiolucent trocar 110, 112 is equipped with a radiopaque element at the tip of the trocar. This helps determine the exact position of the trocar in the straight focus. Figs. 17A to 17B show the use of radiolucent trocars, 110 or 112, to locate the bore 16 in the straight X-ray beam approach. Figs. 17a to 17c are the fluoroscopic images seen by the surgeon with the radiolucent trocar located properly shown in fig. 17c.

Referring to fig. 18, the steering arm 28 is shown with the adjusting device 36 mounted therein in the locked position with the long sleeve 130 mounted in the hole 82 of a left template to guide a drill 132 through the cortical bone on the side lateral of the femur, through the transverse bore 16 of the nail 10 and through the cortical bone on the medial side of the femur.

Referring to fig. 19, the introduction of a first bone screw 136 through the bore 80 of a left template and into the elongated transverse bore 18 of the bone nail 10 is shown. Naturally, this is achieved after the transverse bore 18 has been drilled from a similar to that shown in fig. 18.

Referring to fig. 20, a second bone screw 138 is shown which is inserted through the transverse bore 16 of the bone nail 10 in a manner similar to that of the bone screw 136. The two bone screws are inserted with a standard screwdriver 140 and 142, respectively. To facilitate the use of the handle 146, the screwdriver 140 can be removed so that the handle 148 of the screwdriver 142 can be more accessible. As two bone screws are being used, according to fig. 15 Static blocking or secondary dynamization is used (depending on which end of the elongated hole 18 receives the screw).

Figs. 21 to 29 show the use of the addressing apparatus 20 when used with preferred oblique focus. The oblique approach is preferred because when the X-ray beam is oriented at an angle between 20 ° and 45 ° and preferably 30 ° with the longitudinal axis of the bone nail 10, the operation of the screwdrivers 140, 142 by means of the handles 146, 148 can be carried out by hand outside the X-ray beam. In order to align the adjusting device 36 and, therefore, the holes 80, 82 with the holes 16 and 18 of the nail 10, an indicator of object 150. In the preferred embodiment, as shown in figs. 22, 22a and 22b, the indicator 150 is made of a predominantly radiolucent material such as PEEK and is in the form of a parallelepiped. In the preferred embodiment, a parallelogram design with angles of 30 ° for indicator 150 was chosen due to the operating technique. The angle of the indicator frame is inclined 30 ° with respect to the perpendicular so that when the surgeon places the C-arm at an angle of 40 ° or 20 ° for anatomical reasons (sometimes, the patient's other leg is in the middle of so you need to reorient the angle), you don't see any of the radiopaque markers. If a rectangular design (0 ° with respect to the perpendicular) was used, it would "lose" significantly usable length of the radiopaque indicator during the oblique alignment procedure. The indicator 150 has four legs 152, 154, 156, and 158, respectively. The legs 154 and 156 rest in a first plane parallel to a plane containing the legs 152 and 158. Similarly, the legs 152 and 154 are coplanar with a plane that is parallel to the plane that contains the legs 156 and 158. The legs 154 and 156 are joined by lateral legs 155 and 157 which, as described above, are inclined 30 °. Similarly, legs 152 and 158 are joined by side legs 159 and 161. In the preferred embodiment, as can be seen in fig. 22A, the legs 152 and 154, being mainly composed of a radiolucent material, contain a radiopaque wire of a broken or twisted line 160. In the preferred embodiment, the thread in a broken or twisted line 160 is molded in arms 152 and 154 during the manufacture of object indicator 150. As best seen in fig. 22B, the legs 156 and 158 contain continuous line radiopaque wires 162 which are also preferably molded in place during the manufacture of the object indicator 150. As seen in fig. 22b, the separation between the threads in a continuous line 162 is smaller than the separation between the threads in a dashed or twisted line 160. Thus, the different threads 160 and 162 can be easily distinguished in a fluoroscopic image showing two dashed lines and two continuous lines . Naturally, the threads in a continuous line and the threads in a broken line could be reversed without changing their function, that is, the legs 156 and 158 could have the threads in a broken line 16 and the legs 152 and 154 could have the threads in a continuous line.

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In the preferred embodiment, the object indicator 150 has a recess in the form of a dovetail 164 which is best shown in fig. 21 for coupling the male side extensions in the form of a dovetail 90 and 92 of the body 56 of the adjustment device 36. Referring to fig. 10, when the right femur is approached, the object indicator 150 is mounted on a male dovetail extension 92 and when the left femur is approached, extension 90 is used to mount the object indicator 150. In both cases, the Object indicator 150 extends from the adjustment device 36 towards the proximal end of the nail 10.

Referring to fig. 23, an addressing apparatus 20 is shown mounted on a left femur with the object indicator 150 mounted on the dovetail 90 of the adjustment device 36. The fluoroscopic machine 124 is shown oriented at an angle of approximately 30 ° with respect to the longitudinal axis of the nail 10. It can be seen that, in this position, the X-ray beam 170 is offset with respect to the axis through which the bone screws are introduced into the distal femur and the holes 16 and 18 and, thus, the The surgeon's hands would not enter the X-ray beam.

Referring to fig. 24, the alignment procedure is shown to determine the correct position of the transverse holes 16 and 18 of the nail using the object indicator 150. In the group of four-line images labeled "A" it can be seen that the thread in a broken line 160 in the upper leg 154 and the lower leg 152 is placed above and below the continuous line thread 162 of the leg 156 with the continuous line thread 162 of the arm 158 located below the two threads in the broken line 160. This means that the x-ray beam is not coplanar with the xy plane of the transverse holes 16, 18 of the nail 10. However, when proper alignment is achieved, the line grouping shown in Group B of fig. 24 now coincides with the correct alignment and the separation shown in fig. 22b Thus, the continuous line wires 162 are located between the two dashed line wires 160.

Referring to fig. 25, the use of adjustment device 36 and, therefore, the object indicator 150 to find the threads in dashed continuous line 160, 162 (group "B" of Fig. 24) now aligned with the center of the end is shown. distal of the slotted or elongated opening 18 of the nail 10. The group "A" of threads of 160, 162 shows the center of transverse bore 18 correctly positioned with Group "B" showing the center of the transverse bore 18 correctly positioned. This is achieved by adjusting screw 60 of adjusting device 36 in the direction of arrow "D" of fig. 25. This procedure is shown for the left nail in fig. 26 so that the rotation arrows at the top of the figure indicate the rotation of the screw 60 to adjust the template 74 (in this case, a left template 74) in the Z direction.

Referring to fig. 27, the fluoroscopic image seen by the surgeon is shown when the correct alignment is achieved as shown in fig. 25 "B". The bore 18 is located midway between the threads in a continuous line 162 through the use of the adjusting screw 60.

Referring to fig. 28, the tissue protection sleeve 114, 116 inserted through the hole 80 of the left template 74 is shown. The holes are then drilled in the cortical bone as set forth above with respect to the straight approach for the transverse bore 18 and the cross bore 16. Similarly, the bone screws are inserted as shown in fig. 29 in the same way it was done with the straight approach.

Next, the operative technique for the use of straight and oblique approaches will be described.

In the right approach after assembly of the addressing apparatus 20 and insertion of the nail 10, the appropriate locking template 74 is carried on the fixing pins of the template 66, 68 and is fixed by pushing the locking template towards the pins.

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There are two 74 different templates available. One for static / static mode (right and left) and one for static / dynamic mode. As described, this can be achieved by having the template 44 used on one side on the left nail and on the other side for the right nail.

The positioning pin 58 of the adjusting device is inserted into the bore 42 of the arm 28 and is fixed by rotating the lever 71 clockwise.

The length of the required nail determines the position of the adjusting device 36 in the distal addressing arm 28. The lengths of the nails are preferably marked in the distal addressing arm above the appropriate hole 42.

The adjustment device is calibrated with the addressing device assembled on the nail before insertion into the drill channel.

This can be done on a table in the Q. The calibration places the adjustment device in the correct position to drill the cross drill 16, 18 with the nail in a non-deflected state. Thus, once introduced, the deviation will cause the holes 16, 18 to move only a small amount with respect to the calibration position. The longest drill is assembled into the longest radiolucent tissue protection sleeve to ensure the nail is reached.

The assembly is first taken to the proximal hole 16. The alignment is then checked with a drill to see if it hits the nail hole directly without any resistance. The drill must pass through the nail hole smoothly and easily. If this does not happen, screw 60 is then rotated until there is easy and smooth access through the nail hole. When the proximal orifice is calibrated, then the calibration with the distal orifice is repeated. This would be the correct medial-lateral position of the adjustment device 36 if no flexion occurs during the introduction of the nail.

Calibration is performed first with the hole of the proximal nail. This is done because it is not necessary for the adjustment device 36 to be exactly in the neutral position. It is because the orifice of the proximal distal nail will probably deviate less at the introduction of the nail.

After calibration, the tissue protection sleeve is removed first, followed by the drill sleeve and finally the drill. The coupling of the distal addressing arm 30 can then be released by moving the lever 40 and the fixing bolt 34 is removed. The assembly of the distal addressing device is disassembled and the fixing bolt can be placed in a storage location of fixing bolts molded on the distal addressing arm 28.

The adjustment device is not removed from the distal routing arm to avoid incorrect drilling.

A straight approach may be used, although not preferred. In this approach the x-ray beam is in line with the holes 16 and 18 and is perpendicular to the nail 10.

The distal addressing arm 28 with the adjustable device 36 still assembled is coupled with the handle 22 by means of the coupling device 30.

A radiolucent trocar 110 or 112 is assembled into the corresponding radiolucent tissue protection sleeve 114 or 116 and is pushed through the distal locking hole 80 in template 74 in the adjustment device 36 with the skin.

As shown in figs. 17A and 17B the X-ray view of the round and elongated distal holes is incorrectly aligned. Fig. 17C shows the X-ray beam aligned correctly in the Z plane.

The radiolucent trocar 110 or 112 is equipped with a radiopaque element 120 at the tip 118 of the trocar. This radiopaque element can be used to determine the exact position of the trocar tip in straight focus.

This feature is used to provide an optimal lateral alignment of the tissue protection sleeves with the hole in the nail under X-ray control by rotating the screw 40 of the adjusting device 36. When an appropriate medial-lateral alignment is achieved (flat Z), a radiopaque spot produced by element 120 is centered (see Fig. 17C) and then the radiolucent trocar is replaced by a guide sleeve and a standard metallic trocar.

A small incision is initiated at the tip of the standard trocar, and extends to the lateral cortex of the distal femur. The trocar will normally extend backwards from the sleeve approximately 3 mm when the tissue protection sleeve has reached the lateral cortex. The tissue protection sleeve should be in good contact with the bone (fig. 6).

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A second X-ray control should be performed to ensure that the alignment remains correct. If necessary, an adjustment is made by rotating the handle of the adjustment device until an appropriate alignment is achieved.

The screw length can be determined by any known procedure. For example, the trocar is removed and replaced with a calibrated drill of 4.2 mm x 340 mm. The surgeon drills through the first cortex and, when the second cortex is reached, reads the measurement on a drill scale in the drill. The thickness of the bark, which is approximately 5 mm, is added to this measurement to select the correct screw length.

Alternatively, the drill can be drilled through the second crust and monitored by X-ray or fluoroscopic imaging. The screw length can then be read directly on the scale of the drill.

The second crust is then drilled. It is also possible to measure the correct screw length using a known screw gauge after drilling through the second bark. The drill guide sleeve must be removed and the screw gauge can be advanced through the tissue protection sleeve. The small gauge hook is placed behind the medial cortex and the required length of the locking screw is read on the scale on the gauge.

Screw insertion is performed in a standard manner as in the straight approach as described above by using a screwdriver through the tissue protection sleeve. It acts first on the most distal hole. Preferably, a 5 mm locking screw is inserted through the distal end of the radiolucent tissue protection sleeve using the screwdriver until a mark on the screwdriver shaft approaches the distal sleeve of radiolucent tissue protection 114 or 116. It is made Carefully advance the screw head until it is slightly in direct contact with the cortex.

When a mark on the screwdriver shaft reaches the tissue protection sleeve, it indicates that the screw head is close to the cortex. Care must be taken not to screw in excess. The screw head should come into contact with the cortex and resistance should be felt.

Preferably, the screwdriver shaft is on the left inside the tissue protection sleeve. The screwdriver tip engages on the left on the first screw head and the tissue protection sleeve is pushed over the screw head, against the cortex. This helps ensure system stability. The screwdriver shaft helps keep the steering arm in position. Next, the most proximal hole is approached.

The radiolucent trocar 110, 112 is assembled into the radiolucent tissue protection sleeve 114, 116 and pushed through the proximal locking hole in the skin adjustment device.

The same operative technique is followed as described above for the most distal hole and measurement of the length of the distal screw is performed in the same manner as described above.

The drill sleeve is removed and the full 5 mm screw with the screwdriver is inserted.

The addressing device can then be removed by removing the screwdrivers / sleeves and opening the lever 40 of the distal addressing arm. The fixing bolt 34 is then removed.

In the preferred oblique approach as described above, the X-ray beam is oriented approximately between 20 ° and 45 ° obliquely with respect to the distal locking sleeves and obliquely with respect to the nail. Thus the advantage is offered that, during drilling, the drill tip can be seen, but the image intensifier is not on the axis of the power tool and the drill.

After the calibration described above, the distal steering arm 28 with the adjustment device 36 still assembled is pushed onto the handle portion 26 until the spring latch is felt. In the window of the alignment indicator 38, the white line 39 can be seen in the handle part 26. The fixing bolt 34 is then inserted into the hole until the click is felt and the steering arm lever 40 is locked. The object indicator 150 is then fixed on the proximal grooves in the form of a dovetail 90, 92 (right or left) of the adjustment device 36.

The essential initial stage in distal addressing with the oblique approach consists in placing the image intensifier approximately between 20 ° and 45 ° and preferably 30 ° in oblique with respect to the distal locking sleeves and obliquely with respect to the nail.

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To produce an optimal lateral alignment of hole 16 or 18 in the nail under X-ray control, the C-arm of the X-ray machine is positioned in a manner in which the nail shank is in the middle between the in-line threads discontinuous and the continuous line threads of the object indicator 150 as set forth above.

The adjustment is then made by rotating the handle 40 of the adjustment device 36. An appropriate alignment is achieved when the locking hole is halfway between the wires in a broken and continuous line as shown in fig. 27. Next, drilling and screw insertion are carried out as in the straight insertion as described above.

Although in the oblique approach it is not necessary to use radiolucent trocars 110, 112, they could be used to further indicate the position of the transverse holes 16 or 18 in the nail 10. The image on the fluoroscope would show a line produced by the radiopaque marker 12 rather than a circular point as in the straight approach.

Referring to figs. 30 and 31 shows an alternative object indicator generally denoted by 200. The object indicator 200 includes a first leg 202 and a second leg 204. The legs are connected at a vertex end 206. The object indicator 200 has a groove. dovetail connection 208 for coupling dovetails 90, 92 of the adjustment device 36. The object indicator 200 is preferably made primarily of a radiolucent material such as PEEK.

Next, referring to figs. 30 to 32, the first arm 202 which is made of PEEK includes a series of radiopaque lines formed therein. In the preferred embodiment, the center line 210 is a metal pin having a diameter greater than any of the other metal lines or radiopaque 212 that are formed on the other side of the center line or pin 210.

Referring to fig. 32 shows a top view of the first arm 202 which includes a large central rod 210 and a series of long and short thin radiopaque lines 212 having different lengths. The arm has a plurality of short-length radiopaque lines or elements 214 and a series of longer radiopaque lines or elements 216. In the third embodiment there are three elements or lines 214, 216 fine long and three short in each lateral central pin 210 (up and down in Fig. 32). In the preferred embodiment, the shorter lines 214 are separated in increments of 2.5 mm with respect to the center of the pin line 210 and with respect to the long lines 216. In a preferred embodiment, the lines 216 are 5 mm apart with a shorter line 214 located 2.5 mm from each adjacent line 216. Thus, as shown in fig. 32, the three radiopaque elements or long radiopaque lines 216 are separated by a maximum of 15 mm from a central line 211 of a radiopaque pin 210. In the preferred embodiment, the fine lines 214, 216 within the first leg 202 they are formed by an engraving process comparable to a procedure used in the manufacture of circuit boards in the electronics industry. In the preferred embodiment, the engraved metal gratings are then integrated into the radiolucent (plastic) material in the form of a "sandwich". In the preferred embodiment, the angle formed by the first and second legs at vertex 206 is preferably 30 °. This angle is chosen to keep the surgeon's hand out of the x-ray beam or fluoroscope during use. The angle between the first and second legs can vary between 15 and 60 ° and still allows the surgeon's hands to be out of the X-ray beam during use.

Referring to fig. 33, a second embodiment of the object indicator shown in figs. 31 to 32. This object indicator includes a pivot pin 220 which allows the first leg 202A to rotate with respect to the second leg 204A to form an angle between 15 ° and 60 °. A sear system (not shown) can be used to block the desired angle between the first and second arms. The object indicator 200A is otherwise identical to that shown in figs. 30 to 32 and works in an identical way once the angle is set.

Referring to fig. 34, the addressing system of the present invention is shown with the object indicator of figs. 30-34 mounted on an adjustment element 36 as described above with respect to the object indicator 150. The object indicator is set in an identical manner with respect to the holes in the distal end of the implant, for example, a femoral nail . The only difference is that an alignment pin 222 is placed at the end of the second leg 204 so that it can align with the beam of an X-ray machine 224 shown in fig. 35. Pin 222 appears as a point when the beam is aligned with the second leg 204.

The procedure for using the alternative and preferred object indicator is to attach the object indicator 200 to one of the two dovetail-shaped mounting elements 91, 92 in the adjustment device 36 (depending on whether it is mounted on a right or left femur). A metal trocar 240 is placed in the proximal hole of the adjusting device 36, and an alignment pin or thread k 222 is inserted into the bore at the end of the alignment arm in order to adjust the C-arm of the machine X-ray. Trocar 240 can be housed inside tissue protection sleeve 130. The C-arm is aligned so that the X-ray beam is in line with the second leg 204 and at an oblique angle to the nail 12. A first X-ray capture is made, and the thicker central metal pin 210 shows the theoretical position of the tissue protection sleeve 130 that houses the metal trocar.

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Fig. 36 shows what a first X-ray would look like with the tip 242 of the metal trocar 240 misaligned with the thickest central metal bar on the scale. The C-arm of the X-ray machine should be aligned again so that the metal tip of the trocar 240 is in line with the thicker central metal pin 210. Said alignment is shown in fig. 37. Next, there is a two-line offset (216) between the tip of the 5 metal trocar and the central axis of the hole in the nail 12. Since the long lines 216 of the scale are 5 mm apart, the offset would be approximately 10 mm since the central axis of the hole of the distal nail is aligned with the second line under the axis of the thicker metal bar. As indicated above, the shorter engraved lines 214 are 2.5 mm apart, that is, they are halfway between each pair of long lines 216. Obviously, other scale distances are possible, up and down the metal pin 210 10 thicker central. These displacements with respect to the central line can be caused by deformation of the bone nail during introduction. In any case, from the X-ray scan it can be seen if the metal pin 210 is above or below the hole of the distal nail, and the distance between the two. The adjusting device 36 is adjusted to fully align the tissue protection sleeve and the center of the trocar with the hole in the distal nail (see Fig. 38). As shown in fig. 38, the fabric protection sleeve 130 is

15 fully aligned with the nail, and drilling of the distal hole can be initiated. The hole is drilled in a conventional manner as described above.

Although the invention herein has been described with reference to particular embodiments, it should be understood that these embodiments are merely illustrative of the principles and

20 applications of the present invention. Therefore, it should be understood that numerous modifications can be made to the illustrative embodiments and that other configurations can be devised without departing from the scope of the present invention as defined by the appended claims.

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Claims (13)

one.

An addressing device (20) adapted to direct a transverse bore (16, 18) into a bone nail (10) comprising: an arm member (28) adapted to engage an end portion (24) of a bone nail , wherein the arm member comprises a pointing part (32) extending parallel to a longitudinal axis of the bone nail; an adjustable pointing device (36) mounted on the pointing part, the adjustable pointing device having a guide bore (88, 90) adapted to align with the transverse hole in the nail, the adjustable pointing device being mobile with respect to to the pointing part in a direction perpendicular to a plane containing the longitudinal axis of the nail and the central axis of the transverse bore; and an object indicator (200) mounted on the adjustable pointing device, the object indicator having a radiolucent body that includes first and second angled leg parts that form a vertex at a first end of each part, the first part having of leg radiopaque elements (210, 212, 214) separated in it.

2.

The addressing device according to claim 1 wherein the adjustable pointing device can move in a longitudinal direction along the part of the arm member that extends parallel to the bone nail.

3.

The addressing device according to claim 1 wherein the parts of the first leg include at least three separate radiopaque elements.

Four.

The addressing device according to claim 3 wherein a central radiopaque element is thicker than at least two other radiopaque elements.

5.

The addressing device according to claim 4 wherein the central radiopaque element is a metal rod and the other radiopaque elements are engraved metal.

6.

The addressing device according to claim 5 wherein the at least two other radiopaque elements are separated by at least 2.5 to 5 mm increments above and below the central radiopaque element.

7.

The addressing device according to claim 5 wherein there are at least four other radiopaque elements in combination with the central radiopaque elements.

8.

The addressing device according to claim 7 wherein at least two of the four radiopaque elements have shorter lengths than the central and the other radiopaque elements.

9.

The addressing device according to claim 7 wherein all radiopaque elements rest in the same place.

10.

The addressing device according to claim 1 wherein the first and second leg portions extend from the vertex at an angle between each other between 15 ° and 45 °.

eleven.

The addressing device according to claim 10 wherein the second leg portion includes a radiopaque pin element that extends with respect to the first leg of the angle formed at the intermediate vertex.

12.

The addressing device according to claim 5 wherein the angle is 30 °.

13.

The addressing device according to claim 1 wherein the adjustable pointing device is made of a radiolucent material.