FR3059543A1 - TOOLS FOR OSTEOSYNTHESIS FORMING A GUIDE VIEW FOR TWO AXIAL PINS - Google Patents

Abstract

The invention relates to a tool for osteosynthesis forming a guide and insertion viewfinder in bone parts of two axial pins, comprising a strip (10) supporting a radial front arm (14) having at its end a tip (16) facing rearwardly disposed along a main axis (A1) parallel to this slider (10), and a movable rear arm (20) sliding on said slider (10), supporting a first bushing (32) having a bore arranged along the main axis (A1), characterized in that the rear arm (20) has on the front side rounded depressions (28) allowing the adjustment of fingers of the hand.

Description

059 543

60105 ® FRENCH REPUBLIC

NATIONAL INSTITUTE OF INDUSTRIAL PROPERTY © Publication number:

(to be used only for reproduction orders) (© National registration number

COURBEVOIE © IntCI ⁸ : A 61 B 17/17 (2017.01)

PATENT INVENTION APPLICATION

A1

(© Filing date: 26.10.17. © Applicant (s): NOVASTEP — FR. (30) Priority: 06.12.16 FR 1662015. @ Inventor (s): MEHDI NAZIM and BONIFACE OLI- VIER. (43) Date of public availability of the request: 08.06.18 Bulletin 18/23. (© List of documents cited in the report of preliminary research: The latter was not established on the date of publication of the request. (© References to other national documents ® Holder (s): NOVASTEP. related: ©) Extension request (s): © Agent (s): CABINET GERMAIN & MAUREAU.

A TWO-PIN GUIDE VIEWFINDER

FR 3 059 543 - A1

TOOLS FOR OSTEOSYNTHESIS FORMING AXIALS.

(© The subject of the invention is a tool for osteosynthesis forming a viewfinder for guiding and inserting into bone parts of two axial pins, comprising a strip (10) supporting a front radial arm (14) having at its end a point (16) turned towards the rear arranged along a main axis (A1) parallel to this strip (10), and a movable rear arm (20) sliding on this strip (10), supporting a first socket (32) having a bore arranged along the main axis (A1), characterized in that the rear arm (20) has rounded recesses (28) on the front side allowing adjustment of the fingers of the hand.

i

TOOLS FOR OSTEOSYNTHESIS FORMING A GUIDE VIEWFINDER OF TWO AXIAL SPINDLES

The technical field of the invention is that of a tool for osteosynthesis, in particular a guide and insertion sight for axial elements such as drilling drills, pins or osteosynthesis screws, as well as methods of installing screws with such a tool.

Osteosynthesis is a surgical operation which consists in fixing between them two bony parts like fragments of a broken bone, or two bones close to each other, using axial elements like screws or pins made in metallic materials tolerated by the body, having a shape adapted to the elements to be treated.

The axial element can be left in place permanently, or removed after consolidation of the bone parts by osteosynthesis.

A type of tool known for carrying out the insertion of a pin into two bone parts, comprises a strip having on a front side a fixed front radial arm comprising at its end a front point which is turned towards the rear, arranged along a main axis parallel to this strip. A movable rear radial arm sliding on this strip, can be locked on the strip by a tightening wheel.

The movable radial arm comprises at its end a guide sleeve having a bore arranged along the main axis, capable of receiving in its bore an axial element, in particular a tool for preparing the bone parts such as a drill bit or a spindle.

With this tool, we first adjust the front tip forward of the bone parts, on the axis of the spindle to be put in place, then we slide the rear arm forward, positioning the guide bushing according to this same axis, directly on the back of the bone parts.

With the drilling of the sleeve, there is a guide bore receiving the pin to be put in place.

In this way, positioning accuracy is obtained in the preparation of the bone parts and in the installation of a single spindle. One can in particular then use the spindle as internal guide of a drilling means and of a screw, comprising an axial drilling receiving this spindle.

However, this type of tool has shapes which pose handling problems, in particular for these surgical operations requiring both firm support of the tool and very good positioning accuracy.

Another type of known tool, presented in particular by document US-A1-20130046312, comprises a body equipped with a holding handle, comprising a fixed main socket disposed along a main axis, and a secondary socket inserted in a radial slot. of this body, making it possible to adjust the center distance between these two sockets.

In this way it is possible at the same time to prepare the bone parts to receive two parallel pins, spaced apart by a distance defined by the adjustable center distance between the two sockets, and the insertion of these two pins.

However, this type of tool intended for the installation of two pins poses ergonomic problems, which make it difficult to orient the axes of the pins simply and precisely. Indeed, the main socket and the secondary socket make it possible to position the two rear points of the two axes behind the bone parts by defining the inter-axis, but the orientation of these axes cannot be achieved in a simple manner.

The object of the present invention is in particular to avoid these drawbacks of the prior art.

It offers for this purpose a tool for osteosynthesis forming a viewfinder for guiding and inserting into bone parts of axial pins, comprising a strip supporting a front radial arm having at its end a point turned towards the rear arranged in a main axis parallel to this strip, and a movable rear radial arm sliding on this strip, supporting a first bushing having a bore arranged along the main axis, this tool being remarkable in that the rear arm has along its length on the front side of the rounded hollow allowing adjustment of fingers of the hand.

An advantage of this tool is that the recesses receiving the fingers of the hand allow the complete tool to be held firmly, without the risk of slipping by grasping the rear arm supporting the slide with blocking of the fingers in the recesses, in particular for guiding during operations requiring the application of a certain force with precision, in particular for drilling or screwing in the bones.

The osteosynthesis tool according to the invention may also include one or more of the following characteristics, which can be combined with one another.

Advantageously, the tool comprises two successive recesses ending near the strip.

Advantageously, the strip includes a marking indicating the distance between the front point and the first socket. The total length of the bone part along the main axis is obtained by a quick reading.

Advantageously, the rear arm comprises a means for blocking the sliding on the strip.

Advantageously, the tool supports an additional arm fixed above by a pivot arranged along the main axis, receiving a second bushing having a secondary axis parallel to the main axis.

In this case, advantageously the additional arm comprises a positioning sleeve which adjusts in the bore of the rear arm receiving the first sleeve.

Advantageously, the additional arm has a slot disposed radially, forming a linear guide for the second socket. The slot allows easy and precise adjustment of the center distance between the two sockets.

In this case, advantageously the second socket has a shape fitted in a groove forming the contour of the slot preventing its rotation, and an end thread receiving a threaded plug for its tightening on the additional arm.

Advantageously, the additional arm has at its end opposite to the pivot, a particular shape adapted for handling.

In this case, the particular shape may include a flat end portion having a greater width and a reduced thickness compared to the rest of the additional arm.

The invention also relates to a method of using a tool comprising any one of the preceding characteristics, remarkable in that it comprises the successive operations of placing two pins in the two sockets with the tool. , then removing the tool, and then installing a screw on each spindle.

The invention further relates to a method of using a tool comprising any of the preceding characteristics, remarkable in that it comprises the successive operations of placing a first spindle in the first socket with the tooling, then after the removal of this tooling the installation of a first screw, then the installation of a second spindle using the additional arm equipped with a positioning sleeve installed on the first spindle, and finally after the removal of this additional arm the installation of a second screw.

Other characteristics and advantages of the invention will emerge on reading the description which follows, given solely by way of example, with reference to the following appended figures:

- Figure 1 shows the fusion of the joint between the calcaneus and the talus in orthopedic surgery, by inserting into these bones two parallel screws;

- Figure 2 shows part of a tool according to the invention, intended for guiding and inserting a first screw;

- Figure 3 is a detail view of the movable arm of this tool;

- Figure 4 shows the tool according to the invention which is complete;

- Figures 5 and 6 are detailed views respectively of the second socket and its wheel for the additional arm;

- Figure 7 is a perspective view of the additional arm;

- Figure 8 is a top view of the rear arm showing the possible rotation of the additional arm;

- Figures 9a to 9d successively show the operations for the installation of two screws simultaneously;

- Figures 10a and 11b show alternatively certain operations of this pose; and

- Figures 11a to 11h show successively the operations for installing two screws one after the other;

- Figure 12 shows part of another tool according to the invention;

FIG. 13 is a detail view in section along Al of the movable arm of the tool shown in FIG. 12.

For the sake of clarity, identical or similar elements are identified by identical reference signs in all of the figures.

Figure 1 shows the bones of a person's foot, comprising on the front side indicated by the arrow "AV", a slope 4 connected to the base of a tibia 6, receiving a calcaneus 8 which is necessary towards the rear permanently fix to this slope by two parallel screws 8. Each screw 8 has a body completely passing through the calcaneus 2 in a hole, a rear screw head inserted in a housing at the back of this hole, and a screwed front thread in the slope 4.

Figures 2 and 3 show a tool comprising a smooth strip of square section 10, supporting on the front side a fixed front radial arm 14 comprising at its end a hook ending in a point 16 turned towards the rear, arranged along a main axis Al. The fixed front arm 14 can be removed from the strip 10 so as to change the hook to replace it if necessary by another having a shape adapted to the type of surgical intervention to be performed.

The strip 10 has on one side a marking 12 of height graduated in millimeters, which begins at zero at the end of the front point 16.

A movable rear radial arm 20 comprises a slot receiving in an adjusted manner the square section of the strip 10, closed by a plate 22 tightened on this arm by four screws, to produce a guide allowing a sliding without play of this strip, without possibility of rotation which allows to obtain a precise positioning of this rear arm.

The movable rear arm 20 comprises a lateral tightening wheel 24, comprising a threaded part screwed into a thread of this arm perpendicular to the strip 10, which clamps at its end the side of the strip to ensure blocking of this movable arm on this strip. Any other means of tightening the movable rear arm 20 on the strip 10 can be used.

The movable rear arm 20 has at its end a bore 30 aligned with the main axis A1, receiving a first bush 32 having an axial bore for guiding a spindle, comprising at its end disposed behind the arm a handling tip 34 including an ergonomic grip area.

The guide bore of the first sleeve 32 is suitable for the passage of commonly used pins, having a diameter generally between 1.5 and 3mm.

The height of the front end of the first socket 32 is adjusted on a front transverse face 26 of the arm 20 surrounding the strip 10, which makes it possible to view directly on the graduation marking 12 at this face, the distance between the front end of socket and front tip 16.

The movable rear arm 20 has a distance between the first sleeve 32 and the plate 22 for holding the strip 10, of approximately 70 mm allowing at least three main fingers to pass through the hand.

In addition, the rear arm 20 has on the front side two successive rounded recesses 28 ending near the plate 22 for holding the strip 10, allowing the adjustment of two fingers when this arm is tightened in the hand, without risk of slipping. , in order to achieve an ergonomic grip of this arm to hold the tool firmly and precisely.

The front point 16 at the end of the fixed front arm 14, allows the surgeon to immediately identify the exit point of the spindle which is adjusted in the guide hole of the first socket 32, either visually or by radiological control .

Figures 4, 5, 6 and 7 show an additional arm 40 of flat shape, comprising at one end a bushing 36 for positioning this arm, designed to be adjusted in the bore 30 of the end of the movable rear arm 20, the flat part of this additional arm bearing on the rear face of the movable arm. The front end of the positioning sleeve 36 is similarly adjusted at the front transverse face 26 of the arm 20, to give the same indication of height.

The additional arm 40 has, in its thickness, a slot 44 disposed radially in the axis of this arm, formed over approximately one third of the length of the arm, near the positioning bush 36.

A second bushing 50 comprising an axial guide hole, has an axial part which ends towards the rear by a shoulder 52 having two parallel flats, then by a thread 54. A plug 56 comprising an axial hole allowing the spindle to pass through has on the front side, a threaded part which is screwed onto the thread 54 of the second bush 50.

The slot 44 comprises on each face of the additional arm 40, a groove 46 making the contour of this slot, which receives in an adjusted manner the parallel flats of the shoulder 52 of the second bush 50, giving a connection of the slide type allowing a sliding of this socket along the groove while avoiding its rotation.

After positioning the second socket 50 with a defined center distance with respect to the positioning socket 36, the shoulder 52 is tightened in the groove 46 of the slot 44, by tightening below the plug 56 screwed onto the thread 54 of this second socket, to block this position. In particular, a center distance between 10 and 30mm can be provided.

The additional arm 40 has, on the side opposite to the positioning sleeve 36, after the slot 44, a flat end portion 42 having a greater width and a reduced thickness, facilitating the manipulation of this arm in order to pivot it precisely around of the main axis A1 in order to adjust the angular positioning of the second socket 50, as shown in FIG. 8.

It will be noted that a possible angle of rotation a of the secondary arm 40 is obtained around the main axis A1, which is very large, representing approximately 300 °.

The following successive operations present the installation of two screws 8 simultaneously.

FIG. 9a presents a first operation of positioning the front point 16 of the strip 10 on a front side of the slope 4, in the main axis of a first screw to be implanted.

FIG. 9b shows a second operation of positioning the movable rear arm 20 equipped with the first socket 32, the arm being pushed forward so as to position the front end of this socket in contact with the rear side of the calcaneus 2 , along the main axis.

FIG. 9c shows a third operation of inserting a first pin 60 into the guide hole of the first socket 32, which is inserted into the bones 2, according to the precise orientation of the main axis given by this hole of guidance.

FIG. 9d shows a fourth operation of placing the additional arm 40 with its positioning sleeve 36 fitting in the movable rear arm 20 in place of the first initial sleeve, the center-axis of the second sleeve 50 having been settled beforehand.

The operator adjusts the angular position of the additional arm 40 relative to the rear movable arm 20 simply and quickly in this operation, by acting on the flat end portion 42 to pivot this additional arm about the main axis.

A second pin 62 is inserted with precise positioning in the guide hole of the second socket 50.

FIG. 9e presents, after the removal of the tool, leaving the two pins 60, 62 in place, a fifth operation with a tool 66 for axial drilling around the first pin 60 to receive a first hollow screw 8.

FIG. 9f shows the mounting and tightening of the first screw 8. This fifth operation is repeated for the establishment of a second hollow screw 8 placed on the second pin 62, then its tightening.

As a variant of the second, third and fourth operations presented above, FIG. 10a shows the simultaneous positioning of the two guide sleeves 36, 50, along the two axes provided for the two screws.

FIG. 10b then presents the simultaneous insertion of the two pins into the two guide bushes 36, 50. The fifth operation presented above is then carried out, comprising the removal of the tools and the installation of the two screws 8 .

The following operations present the installation of two screws 8 carried out successively.

FIG. 11 a presents a first operation for positioning the front point 16 of the strip 10 on a front side of the slope 4, in the main axis of a first screw to be implanted.

FIG. 11b shows a second operation of positioning the movable rear arm 20 equipped with the first socket 32, the arm being pushed forward so as to position the front end of this socket in contact with the rear side of the calcaneus 2 , along the main axis.

FIG. 11c shows a third operation of inserting a first pin 60 into the guide hole of the first socket 32, which is inserted into the bones 2, 4 according to the precise orientation of the main axis given by this hole. guide.

FIG. 11d presents, after the removal of the tool, leaving the first pin 60 in place, a fourth operation with the drilling tool 66 provided for receiving a first hollow screw 8.

As a variant, it is possible to leave the tool in place, and use drills passing through the first socket 32.

FIG. 11a presents a fifth operation for placing and tightening the first screw 8.

FIG. 11f shows a sixth positioning operation of the additional arm 40 by adjusting the positioning bush 36 on the first spindle 60, then the positioning of the second spindle 62 which is adjusted and positioned precisely in the second bush 50.

FIG. 11g shows a seventh operation with the drilling tool 66 for the second hollow screw 8.

FIG. 11h shows an eighth operation of placing and tightening the second screw 8.

This is done in this way after installing and tightening the first screw 8, parallel mounting with a precise center distance of the second screw relative to this first screw.

The tool according to the invention makes it possible to install screws and pins, and more generally all types of axial elements arranged in parallel, making it possible to connect the bones. One can in particular with the same tool install more than two parallel axial elements between.

The tool according to the invention shown in Figures 12 and 13 differs from that described above in several aspects, independent of each other.

First, the body of the radial arm 20 has been hollowed out so as to reduce the overall mass of the assembly, while preserving the mechanical strength necessary to ensure the proper functioning of the tool.

Furthermore, the rear arm 20 is equipped with another alternative locking system in place of the wheel 24. More specifically, the strip 10 has an external lateral face 110 forming a rack designed to cooperate with a button 120 carried by the rear arm 20. Thus, it is possible to very finely adjust the position of the rear arm 20 along the strip 10 by exerting a simple pressure on the button 120 while sliding the rear arm 20. It then suffices to release the buoton 120 to freeze the position of the rear arm 20 on the strip 10.

In this example, the front radial arm 14 is disposed orthogonally to the strip 10.

Finally, the bore 30 comprises one or more toric springs 130 (only one is visible in FIG. 13), to ensure a better connection between the rear arm 20 and the first bush 32.

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Claims (9)

1. Tools for osteosynthesis forming a viewfinder for guiding and inserting into bone parts (2, 4) axial pins (60), comprising a strip (10) supporting a front radial arm (14) having at its end a point (16) turned towards the rear disposed along a main axis (Al) parallel to this strip (10), and a movable rear radial arm (20) sliding on this strip (10), supporting a first socket (32) having a bore arranged along the main axis (Al), characterized in that the rear arm (20) has rounded recesses (28) on the front side allowing adjustment of the fingers of the hand. 2. Tool according to claim 1, characterized in that it comprises two successive recesses (28) ending near the strip (10). 3. Tool according to claim 1 or 2, characterized in that the strip (10) has a marking (12) indicating the distance between the front point (16) and the first socket (32). 4. Tool according to any one of the preceding claims, characterized in that the rear arm (20) comprises a locking means (24) of the sliding on the strip (10). 5. Tool according to any one of the preceding claims, characterized in that it supports an additional arm (40) fixed above by a pivot arranged along the main axis (Al), receiving a second bushing (50) having an axis secondary (A2) parallel to the main axis (Al). 6. Tool according to claim 5, characterized in that the additional arm (40) comprises a positioning bush (36) adjusting in the bore of the rear arm (20) receiving the first bush (32). 7. Tool according to claim 5 or 6, characterized in that the additional arm (40) has a slot (44) arranged radially, forming a linear guide for the second socket (50). 8. Tool according to claim 7, characterized in that the second sleeve (50) has a shape (52) fitted in a groove (46) forming the contour of the slot (44) preventing its rotation, and an end thread (54) receiving a threaded plug (56) for tightening it on the additional arm (40). 9. Tool according to any one of claims 5 to 8, characterized in that the additional arm (40) has at its end opposite the pivot, a particular shape (42) adapted for grip. 1/6