FR2706278A1 - Prosthesis, grip element for prosthesis, tool for fixing the grip element and device for manipulating the prosthesis - Google Patents

Abstract

The present invention relates mainly to a prosthesis, in particular in the form of plates, to a grip element for the prosthesis, to a tool for fixing the grip element onto the prosthesis and to a device for manipulating the prosthesis fitted with the grip element. A prosthesis according to the invention is fitted with means for temporary attachment to means for gripping and/or manipulating the prosthesis during an operation. The present invention applies mainly to the production of orthopaedic prostheses which are easy to manipulate and, in particular, maxillofacial prostheses, neurological prostheses and osteosynthesis prostheses in general.

Description

PROSTHESIS, GRIPPING ELEMENT FOR PROSTHESIS, TOOL
FOR FIXING THE GRIPPING ELEMENT AND DEVICE
FOR HANDLING THE PROSTHESIS
The present invention relates mainly to a prosthesis, in particular in the form of plates, to a gripping element of the prosthesis, to a tool for fixing the gripping element to the prosthesis and to a device for handling the prosthesis provided with the gripping element.

 To facilitate the reduction of bone fractures, it is known to implant prostheses made of biocompatible materials, in particular titanium.

These prostheses for example have the form of a plate comprising fixing holes through which pass screws ensuring the joining of the prosthesis with the bone elements. The prosthesis is deformed by the surgeon to adapt to the configuration of the assembled bone elements and / or to induce mechanical tension favoring the reduction of the fracture. Securing the prosthesis with the bone elements typically comprises the steps of:
a) position the prosthesis in relation to the bone elements,
b) make pilot holes opposite the prosthesis holes,
c) make holes for receiving the fixing screws,
d) screw the fixing screws into the receiving holes through the prosthesis openings.

 The handling of the prosthesis during these operations is extremely inconvenient. Thus, EP-A-0 423 420 has proposed plate-shaped prostheses comprising a plurality of openings for the passage of the fixing screws connected by a fixing element to an identification plate capable of serving as gripping members. the prosthesis. The plate fixing element has a zone of lower breaking strength.

After securing the prosthesis with the bone elements, the identification plate and its fixing element are removed by breaking or cutting the fixing element at the level of the weakest resistance.

 The prosthesis proposed in EP-A-0 423 420 has many drawbacks: the ablation of the plate provided with its fixing element at the level of the weakest breaking strength degrades the biocompatibility of the prosthesis. Indeed, the biocompatibility is obtained by a judicious choice of the material, for example titanium and by a precise manufacturing ensuring an impeccable surface condition. For example, the bioprostheses according to the invention are made of titanium having undergone a finishing operation comprising a micro-billing step consisting of a spraying of glass micro-beads in order to blunt the sharp angles, but above all a final step of the manufacturing process called passivation in a dilute nitric acid bath, the aim of which is to return the entire plate to a passive state and thus to reinforce its resistance to various attacks which may harm its biocompatibility.

 It is understood that the rupture of the prosthesis of EP-A-0 423 420 at the level of the weakest resistance to rupture exhibits a heterogeneity which is highly detrimental to biocompatibility. The rupture zone is not passivated, and moreover constitutes an aggressive zone for the surrounding tissues.

 It is understood that the rupture of the prosthesis at the level of the weakest resistance to rupture cannot have an impeccable surface state, guarantee of a very good biocompatibility.

 Unless it deforms, which risks leading to a premature rupture of the zone of weakest resistance to rupture, the identification plate has only one degree of freedom, which risks not sufficiently facilitating the task of the surgeon.

 The prosthesis of EP-A-0 423 420 is a single piece including the identification and gripping plate. This results in a high cost price. Indeed, the gripping element is not reusable; this is all the more serious since it is made of an expensive material because it is biocompatible, such as for example titanium.

 It is therefore an object of the present invention to provide a prosthesis, in particular in the form of plates ensuring easy gripping and handling while ensuring excellent biocompatibility.

 It is also an object of the present invention to provide such a prosthesis allowing the positioning and easy removal of the gripping members.

 It is also an object of the present invention to provide a prosthesis provided with a gripping element capable of being manipulated by the surgeon with several degrees of freedom.

 It is also an object of the present invention to offer a prosthesis having a low cost price.

 According to the invention, these aims are achieved by a prosthesis provided with means of temporary securing with means for gripping and / or handling the prosthesis during an operation.

 The invention mainly relates to a prosthesis, in particular orthopedic, in the form of a plate comprising means for securing with a bone, characterized in that it also comprises means for temporary fixation, means for gripping and / or manipulation of the prosthesis, these temporary fixing means being biocompatible allowing their implantation with the prosthesis during a surgical operation.

 The invention also relates to a prosthesis, characterized in that the means for provisionally fixing the means for gripping and / or handling the prosthesis comprise a tapped hole.

 The invention also relates to a prosthesis, characterized in that the tapped hole is made in a tongue located at one end of the prosthesis.

 The invention also relates to a prosthesis, characterized in that said prosthesis is a maxillofacial prosthesis.

 The invention also relates to a prosthesis, characterized in that the prosthesis is a neurosurgical prosthesis.

 The invention also relates to means for gripping a prosthesis, characterized in that said gripping means comprise a spherical contact surface forming a ball joint.

 The invention also relates to gripping means, characterized in that they comprise means for receiving a screwing tool, said receiving means comprising a slot and means for centering the tip of a blade d 'a screwdriver.

 The invention also relates to a screwing tool, in particular a screwdriver, gripping means, in a prosthesis according to the invention, characterized in that it comprises means for temporarily fixing the gripping means when they are fixed to the prosthesis.

 The invention also relates to a screwing tool, characterized in that the temporary fixing means comprises an elastic sheath, in particular made of silicone, surrounding the blade of the screwing tool and ending before the tip of the blade so to grasp the contact surface of the means for gripping the prosthesis.

 The invention also relates to a handling device by means of a gripping means, characterized in that it comprises jaws between which is formed a cavity having an opening, the shape of the cavity being adapted to the shape of the contact surface of the prosthesis gripping means.

 The invention also relates to a device for manipulating a prosthesis, characterized in that it comprises means for temporarily securing with the prosthesis at the level of the fixing means, in particular a threaded rod.

 The invention also relates to a handling device, characterized in that it comprises means making it possible to orient with immobilization the prosthesis to be handled.

 The invention also relates to a handling device, characterized in that the means for orienting the prosthesis to be handled comprise a cardan joint as well as means for locking the cardan joint in a desired position.

The invention will be better understood by means of the description below and the appended figures given as explanatory examples and in which:
- Figure la is a plan view of a first embodiment of a prosthesis according to the invention;
- Figure lb is a sectional view along AA of Figure la;
- Figure 2a is a plan view of a second embodiment of a prosthesis according to the invention;
- Figure 2b is a section along AA of Figure 2a;
- Figure 3a is a plan view of a third embodiment of a prosthesis according to the invention;
- Figure 3b is a section along AA of Figure 3a;
- Figure 4a is a plan view of a fourth embodiment of a prosthesis according to the invention;
- Figure 4b is a section along AA of Figure 4a;
- Figure 5a is a plan view of a fifth embodiment of a prosthesis according to the invention;
- Figure 5b is a section along AA of Figure 5a;
- Figure 6a is a plan view of a sixth example of
production of a prosthesis according to the invention;
- Figure 6b is a section along AA of Figure 6a;
- Figure 7a is a plan view of a seventh example of
production of a prosthesis according to the invention;
- Figure 7b is a section along AA of Figure 7a;
- Figure 8a is a plan view of an eighth example of
production of a prosthesis according to the invention;
- Figure 8b is a section along AA of Figure 8a;
- Figure 9 is a side view of the preferred example of
production of the prosthesis gripping element according to the invention;
- Figure 10 is an alternative embodiment of the element of
gripping of Figure 9;
- Figure 1 1 is a perspective view of the prosthesis of Figure 8 provided with the gripping element of Figure 9;
- Figure 12 is a plan view, partially broken away of a first embodiment of a prosthesis handling device according to the present invention;
- Figure 13 is an enlarged view of the end of the tool of Figure 12 provided with a gripping element of Figure 9 or 10;
- Figure 14 is a top view of the upper part of the tool of Figure 12;
- Figure 15 is a side view of a device for handling and gripping prostheses according to the present invention;
- Figure 16 is a top view of the device of Figure 15;
- Figure 17 is a side view with partial cutaway of a tool for fixing a gripping element on the prosthesis according to the present invention
- Figure 18 is a side view with partial cutaway of another device for handling a prosthesis according to the present invention
- Figure 19 is a plan view of an exemplary embodiment of a neurosurgical prosthesis according to the present invention.

 In FIGS. 1 to 19, the same references have been used to designate the same elements.

 In FIGS. 1 to 8 and 11, examples of maxillofacial prostheses 1 can be seen in the form of a plate made of biocompatible materials, for example titanium, implantable stainless steel or other biocompatible materials comprising a plurality of openings 3 for receiving a fixing screw (not shown) of the prosthesis 1 on a bone element. Each opening 3 comprises for example a tapered bore at 90 capable of retaining a tapered screw head. The prosthesis 1 according to the invention has sufficient rigidity to ensure the cohesion of the various bone elements to be maintained. However, it can be deformed to adapt to the configuration of said bone elements. The prosthesis 1 according to the present invention comprises means 5 for temporarily fixing a means for gripping and / or handling the prosthesis by a surgeon during an implantation operation. The fixing means 5 form an integral part of the prosthesis 1. It is therefore necessary, on the one hand, to avoid or minimize any protuberance which could prove to be troublesome for the patient or even to disturb the biocompatibility. On the other hand, the means 5 for temporary fixing of a means for gripping and / or handling the prosthesis 1 must not compromise these mechanical characteristics and, in particular, must not constitute an initiation of rupture of the prosthesis during its shaped to adapt to the geometry of the patient's bone elements.

 In the preferred embodiment illustrated in the figures, the means 5 comprise a threaded opening advantageously located at one end of the prosthesis.

 This arrangement avoids creating a zone of lower resistance between the openings 3 for receiving the fixing screws.

 As will be explained below, the tapped hole 5 makes it possible to screw a gripping means, for example the ball joint gripping screws of FIGS. 9 and 10 for the duration of the phase of securing the prosthesis, with the bone elements during the operation. Once the prosthesis is in place, we unscrew the gripping element 7, which allows, on the one hand, to limit to a minimum the increase in the size of the prosthesis 1 corresponding to a tongue 9 in which is practiced the tapped hole 5 and, on the other hand, the subsequent reuse of the gripping means. In addition, the gripping means can be made of a resistant and relatively inexpensive material, such as for example stainless steel, which reduces the cost price.

 In the examples illustrated in Figures 1 to 8, the prosthesis 1 has a thickness of 1 mm. The minimum distance between two openings 3 for receiving the fixing screws is 6.35 mm; the width at an opening 3 is 4.5 mm; the openings 3 are connected by elongate elements 1 1 having a width of 2 mm; the hole 5 has an internal diameter of 0.75 mm; The distance between the tapped hole 5 and the nearest screw receiving opening 3 is equal to 2.8 mm or preferably 3.8 mm.

 It is understood that these dimensions are given only for information concerning the best exemplary embodiment and do not in any way constitute a limitation of the invention.

 In FIG. 1, a first example of a linear embodiment of the prosthesis 1 according to the present invention is shown, comprising four openings 3 for receiving the aligned fixing screws.

 In FIG. 2, we can see a prosthesis 1 according to the present invention in the shape of a T comprising five openings 3 for receiving fixing screws, the horizontal bar as well as the vertical bar of the T each have three openings 3, an opening being at the intersection of the vertical bar and the horizontal bar of the T being common to these two bars. The opening 5 for fixing the gripping means is formed in a tongue 9 located at one end of the horizontal bar of the T.

 In FIG. 3, we can see a prosthesis 1 according to the invention in I comprising two parallel bars connected in their middle by an orthogonal bar. Each of the parallel bars is provided with two openings 3 for receiving the fixing screws. The tongue 9 in which the opening 5 for fixing the gripping means is formed is situated at the end of one of the two shortest bars of I.

 In FIG. 4, one can see a variant of prosthesis of FIG. 3 in which the longest bar of the I connecting the two parallel bars itself has two openings 3 for receiving the fixing screws.

 In FIG. 5, one can see a prosthesis 1, according to the present invention, linear comprising six openings 3 for receiving the fixing screws aligned and regularly distributed over the entire length of the prosthesis.

 In FIG. 6, one can see a linear prosthesis 1 according to the present invention comprising six openings 3 for receiving the fixing screws distributed in two groups of three connected by a central element.

 In FIG. 7, one can see a prosthesis 1 according to the present invention comprising two arms making an angle of 110 .. The two arms comprise an opening 3 for receiving the common fixing screws, a longer arm further comprises two other openings 3 for receiving the fixing screws, a shorter arm further comprises an opening 3 for receiving the fixing screws as well as the tapped hole 5 for receiving the means for gripping the prosthesis 1.

 In FIG. 8, one can see an example of prosthesis 1 in X symmetrical with respect to two perpendicular planes and comprising six openings 3 for receiving the fixing screws. One end of the X comprises the tongue 9 comprising the opening 5 for fixing a gripping means.

 In Figure 9, we can see the preferred embodiment of the gripping means 7 according to the present invention. The means 7 comprise on the one hand means 13 for securing with the prosthesis 1 at the level of the fixing means 5 and a contact surface 15 allowing the gripping of the prosthesis. In the advantageous example illustrated, the securing means 13 comprise a threaded rod 16 capable of being screwed into the opening 5 of the prosthesis 1 as well as, advantageously, means 17 for receiving a screwing tool 19, by example a slot for receiving the screwdriver of FIG. 17. In the example of FIG. 10, the gripping means 7 also comprise recesses 21 for centering the screwdriver 19.

 Advantageously, the contact surface 15 is spherical or substantially spherical so as to form a ball joint in cooperation with a gripping tool 23, for example with the pliers illustrated in FIGS. 12 to 16. This ball joint has many advantages. On the one hand, the spherical surface 15 provides centering between the jaws of the handling device 23. In addition, it provides two degrees of freedom in the positioning of the handling device 23 relative to the axis of the gripping means 7, for example in a cone whose opening angle to the axis is equal to 26-. In addition, the spherical surface 15 has excellent wear resistance and excellent tolerance in the event of low local wear.

 It is understood that the gripping means 7 of Figures 9 and 10 are given only by way of non-limiting examples. For example, it is possible to use a cylindrical contact surface ensuring a single degree of freedom or a notched contact surface in which the grip angle by a handling device varies discreetly. Similarly, the means 17 for receiving the screwing tool can have, for example, a polygonal shape, for example square or hexagonal.

 In FIG. 11, one can see a prosthesis 1 in FIG. 8 provided with a gripping means 7 in FIG. 9 allowing the surgeon to manipulate the prosthesis 1 using a manipulation device 23 as for example the forceps of FIGS. 12 to 14 or 15 and 16. The forceps of FIGS. 12 to 14 comprise for example two manipulation arms 25 and 27 articulated around an axis 29 and extended by the jaws 31, respectively 33, the ends form a receiving cavity 35 of the contact surface 15 of the gripping means 7. The shape and dimensions of the cavity 35 are adapted to the geometry and dimensions of the contact surface 15. In the example illustrated on the Figures 12 to 14 adapted to the gripping means 7 of Figures 9 and 10, the cavity 35 having the shape of a sphere portion is terminated by an opening 37 allowing the passage of the rod of the gripping means 7 ensuring the connection with the means of solidarisatio n with prosthesis 1. The opening 37 also allows the orientation of this rod, for example in a cone, in order to adopt the most convenient position for the surgeon.

 Conventionally, the clamp 23 is, on the one hand, provided with a return spring 37 tending to keep the clamp 23 open and, on the other hand, means 39 for locking the clamp in the closed position. The handling arm 25 ends in a gripping ring 41 and the handling arm 27 ends in a handling ring 43.

 In FIG. 17, one can see the preferred embodiment of screwing tools 19 of the gripping means 7. This preferred embodiment corresponds to a tool of the screwdriver type comprising a rod or blade 45 finished at a first end by a point 47 whose shape is adapted to that of the receiving means 17 of the gripping means 7.

The screwdriver 19 comprises a handle 49, for example of plastic material fixed on the extension of the blade 45 by means of a pin 51 (partially shown) and a shouldered ring 53.

 The loss of the gripping means 7 would risk causing them to leave the operating field and thus their contamination, which would require their sterilization before they can be used during an operation.

 Advantageously, the screwdriver 19 comprises means 55 of the gripping means 7 during their fixing to the prosthesis 1. In the advantageous example illustrated in FIG. 17, the means 55 of temporary fixing comprise a flexible sheath, advantageously made of silicone covering the blade 45 of the screwdriver and stopping 2 mm from the tip 47. When the surgeon wishes to fix the gripping means 7 on a prosthesis 1, he penetrates the tip 47 of the screwdriver 19 into the receiving means 17, this which simultaneously grips the contact surface 15 by the sheath 55. Advantageously, the screwdriver 19 comprises means 57 for fixing the sheath 55 around the blade 45 fixed by a ring 59 itself fixed on the blade 45 by two screws headless 61.

 In Figures 15 and 16, we can see a second embodiment of a handling device 23 for gripping the gripping means temporarily secured to the prosthesis 1. The handling device 23 has two branches 65 and 67 completed at a first end, advantageously bent, by a jaw 69, respectively 71, gripping the contact surface 15 of the gripping element 7 and elastically joined at an opposite end 73, so that at rest the jaws 69 and 71 are spaced apart by a distance, for example equal to 4 mm, greater than the dimensions of the contact surface 15. The branches 65 and 67 are provided with locking means 75, for example each branch is provided with a hook s' engaging one in the other when the jaws 69 and 71 are brought closer when gripping the surface 15 of the gripping element 7.

 The jaws 69 and 71 have a geometry and a surface treatment making it possible to grip and block the contact surface 15 of the gripping element 7 in the position desired by the surgeon.

 The clamp 23 advantageously comprises grooves 77 facilitating its gripping. The clamp 23 is of course made of a material capable of being sterilized for use in the operating field.

 In FIG. 18, one can see a device 79 for handling the prosthesis 1, capable of being directly temporarily attached to the latter at the level of the fixing means 5 without the use of gripping elements 7.

 The device 79 in FIG. 18 has a structure substantially similar to that of the fixing tool 19 in FIG. 17 but comprises at one end fixing means 81 capable of cooperating with the fixing means 5 of the prosthesis 1. In the advantageous case where the fixing means 5 of the prosthesis 1 comprise a threaded hole, the fixing means 81 comprise the corresponding screw pitch.

 In the advantageous example illustrated in FIG. 18, the fixing means 81 can be oriented relative to the handle 49, for example by means of a cardan joint 83 comprising locking means, for example a clamping screw (not shown). In a second alternative embodiment of the handling device 79, the orientation of the fixing means 81 is fixed relative to the handle 49. In such a case, it may be advantageous to have a plurality of prosthesis handling devices 79 , each corresponding to a different orientation of the fixing means 81 relative to the handle 49. In such a case, the surgeon chooses the device 79 whose orientation suits him best for the operation in progress.

 It is understood that both the pliers 23 and the screwdriver 19 or the tool 79 can be sterilized so that they can be used repeatedly in the operating field.

 It is understood that the present invention is in no way limited to maxillofacial prostheses. They apply to other types of orthopedic prostheses, such as for example neurosurgical prostheses, an example of which is illustrated in FIG. 19 or osteosynthesis prostheses in general.

 In FIG. 19, one can see an example of neurosurgical plates according to the present invention comprising four vertical bars 85.1 to 85.4 joined by four horizontal bars 87.1 to 87.4.

In the example illustrated in FIG. 19, the horizontal bars 87.1 to 87.4 are regularly distributed, while the distance between the bars 85.1 and 85.2, on the one hand, and between the bars 85.3 and 85.4, on the other hand, is equal to 6.35 mm while the distance between the bars 85.2 and 85.3 is equal to 12.7 mm.

 The neurosurgical plates are thinner than the maxillofacial plates, the plate in FIG. 19 having for example a thickness of 0.6 mm.

 The openings 3 for receiving the fixing screws are provided at the intersections of the horizontal and vertical bars. The fixing means 5, advantageously a tapped hole, are arranged on a tongue 9 extending the vertical bar 85.1, the distance between the tapped hole 5 and the hole 3 for receiving the nearest fixing screw being equal to 3, 8 mm.

 The present invention applies in particular to the production of chinurgical prostheses.

 The present invention applies mainly to the production of easily manipulable orthopedic prostheses and in particular maxillofacial prostheses, neurological prostheses, and osteosynthesis prostheses in general.

Claims (13)

 1. Prosthesis, in particular orthopedic, in the form of a plate comprising means (3) for securing with a bone, characterized in that it also comprises means (5) for temporary fixation, means (7) for gripping and / or handling (23, 79) of the prosthesis (1), these means (5) of temporary fixation being biocompatible allowing their implantation with the prosthesis (1) during a surgical operation.  2. Prosthesis according to claim 1, characterized in that the means (5) for temporary fixing of the means (7) for gripping and / or handling (23, 79) of the prosthesis (1) comprise a tapped hole.  3. Prosthesis according to claim 2, characterized in that the tapped hole is made in a tongue (9) located at one end of the prosthesis (1).  4. Prosthesis according to any one of the preceding claims, characterized in that said prosthesis is a maxillofacial prosthesis.  5. Prosthesis according to any one of claims 1 to 3 characterized in that the prosthesis (1) is a neurosurgical prosthesis.  6. Means for gripping a prosthesis according to any one of the preceding claims, characterized in that said gripping means (7) comprise a spherical contact surface forming a ball joint.  7. gripping means according to claim 6, characterized in that they comprise means (17) for receiving a screwing tool (19), said means (17) for receiving comprising a slot and means for centering the tip (47) of a blade (45) of a screwdriver (19).  8. screwing tool, in particular screwdriver, gripping means according to any one of claims 6 or 7, in a prosthesis according to any one of claims 1 to 5, characterized in that it comprises provisional fixing means (55) gripping means (7) when fixed to the prosthesis (1).  9. screwing tool according to claim 8, characterized in that the temporary fixing means (55) comprises an elastic sheath, in particular made of silicone, surrounding the blade (45) of the screwing tool (19) and ending before the tip (47) of the blade (45) so as to grip the contact surface (15) of the means (7) for gripping the prosthesis (1).  10. Device for handling a prosthesis according to any one of claims 1 to 5 by means of a gripping means (7), characterized in that it comprises jaws (31, 33) between which is formed a cavity (35) having an opening (37), the shape of the cavity (35) being adapted to the shape of the contact surface (15) of the means (7) for gripping the prosthesis (1).  11. Device for handling a prosthesis according to any one of claims 1 to 5, characterized in that it comprises means (81) for temporary attachment to the prosthesis (1) at the level of the fixing means (5) , including a threaded rod.  12. A handling device according to claim 11, characterized in that it comprises means (83) for orienting with immobilization the prosthesis (1) to be handled.  13. A handling device according to claim 12, characterized in that the means (83) for orienting the prosthesis (1) to be manipulated comprise a cardan joint as well as means for locking the cardan joint in a desired position.