WO2018024617A1

WO2018024617A1 - Deployable implant

Info

Publication number: WO2018024617A1
Application number: PCT/EP2017/069096
Authority: WO
Inventors: David François FISCHER LOKOU
Original assignee: Spine Arch Brevet
Priority date: 2016-08-05
Filing date: 2017-07-27
Publication date: 2018-02-08
Also published as: FR3054788B1; FR3054788A1

Abstract

The present invention relates to a novel medical implant for the fixation of at least two adjacent bone elements in a manner that is quick, reliable and not very invasive. This implant consists of a curved hollow rod comprising at least one deployable anchoring means allowing said implant to be immobilised. The present invention also describes a method for the fixation of at least two adjacent bone elements implementing this novel implant. This method is particularly suitable for solidly connecting at least two vertebrae in order to perform an arthrodesis, said implant then being curved, making it particularly suitable for spinal surgery.

Description

DEPLOYABLE IMPLANT

The present invention relates to a novel implant for medical use for fixing at least two adjacent bone elements quickly, reliably and minimally invasive. The present invention also describes a method of attaching at least two adjacent bone elements implementing this new implant. This method is particularly suitable for the joining of at least two vertebrae for performing arthrodesis; said implant being of curved shape which makes it particularly suitable for spine surgery.

In view of the aging of the population and also the pace of life of the active population, bone problems generate or are part of the clinical picture of many pathologies. In addition, trauma associated with accidents, shocks and falls may also cause bone problems requiring surgery. The possibility of fixing bone elements together in order to stabilize or correct a given position is therefore an important medical issue. Indeed, in the field of spine surgery in particular the fact of being able to join bone elements in order to stabilize given areas and / or to release compressed nerve bundles is often the only way to relieve patients.

In the field of orthopedic surgery, plates and screws are commonly used to stabilize adjacent bone areas or to give them a given position. The materials used are obviously solid and many mechanical stresses are imposed by the material and the material. To allow more adaptation and allow more opportunities for surgeons, different devices were implemented to allow a better surgical response for each patient: surgical screws in combination at different angles, fixed plates, articulated plates, cages, etc. In the particular field of spine surgery, surgeons generally use pedicle screws also called tulip screws to secure the vertebrae. These screws for medical use are straight screws which allow the arthrodesis, that is to say the bone fusion between at least two vertebrae. This technique is commonly used in cases of fracture, scoliosis, instability and severe pain. Although this technique is very commonly practiced, the placement of pedicle screws remains a difficult procedure that is reserved for specialized surgeons and is likely to lead to false trips. In cases of false paths, one or more screws are not properly placed, they can hurt the nerve roots or have a lack of strength. To overcome this possibility of false path, several sophisticated guidance systems are used by surgeons as "navigation" including infra-red locations coupled to an intraoperative scan. These navigation systems can reduce the risk of trajectory error. However the risk of error remains important because the arthrodesis performed to date require at least four pedicle screws and more often six to eight pedicle screws.

Thus, the techniques used to date have several drawbacks, including the complexity of the devices to be implanted, the transepicular approach for the fixation screws of these devices which is relatively invasive and generates side effects (hemorrhages, nerve damage, etc.). the need for follow-up involving imaging techniques performance, ie all of the risk factors, technical factors and costs that must be taken into consideration.

The presence of nerves, blood vessels and other tissues that must necessarily be preserved during bone surgeries requires limited access and access for the surgeon. The errors of trajectories are all the more numerous as the access way (s) are difficult or cramped. In certain cases, given the spatial configuration of the bone elements to be joined together the techniques known from the prior art offer no solution. There is therefore a real need for new technical solutions opening new possibilities for fixing bone elements in specific configurations. According to a first characteristic of the invention, the curved implant is one of these solutions, and has however never been proposed to date. Indeed, the implant according to the invention has the advantage of allowing the establishment of a solid attachment requiring a single access path. The curved shape makes it possible to work access ways offering working angles that are not suitable for the rectilinear screws known from the prior art.

Another advantage of the invention is to strengthen the attachment of the implant by adding lateral anchoring means in the bone, and particularly rigid means that deploy laterally outside the implant.

The present invention proposes a simple surgical implant which makes it possible to achieve the fixation of at least two adjacent bone elements, for example two adjacent vertebrae, without risk of false journey, without particular technical difficulty and without expensive technical assistance other than a simple apparatus. of fluoroscopy. In the case of surgery of the spine, unlike the technique using pedicle screws, the implants according to the present invention are not positioned in the vertebral pedicles but allow to directly fasten the vertebral bodies together. The device is immediately stronger than pedicle screws commonly used in the prior art. On the other hand the vertebral bodies being bulky, of the order of 4 x 5 x 3 cm, the risk of an extracorporeal journey is very limited compared to the vertebral pedicles which are 1 x 0.8 cm and are quite difficult to identify even with powerful imaging techniques.

The present invention therefore also proposes a new method of fixing at least two adjacent bone elements, for example two adjacent vertebrae, without the risk of false path and without particular technical difficulty for a surgeon. This method also saves considerable time in the case of the stabilization of more than two adjacent bone elements such as several vertebral stages. Moreover this new surgical implant is placed directly in the bone element, without staples or nails, so an arthrodesis operation for example can be performed closed rachis between the nerve bundles and without damaging the nerves.

In the present invention, the terms in quotation marks are used to describe the new surgical implant, the new method of fixation and its constituent elements. They are used in the plural as in the singular.

By "patient" is meant a human being or an animal whose symptoms or pathology require the intervention of a surgeon for the joining of at least two bone elements between them. For example, a patient is an individual who has had a vertebral fracture or scoliosis, a vertebral collapse, etc. the proposed method of relieving pain of said patient being the realization of an arthrodesis, that is to say the bone fusion between two vertebrae.

By "bone element" is meant anatomical bone elements requiring stabilization or repair surgery but also any implant that replaces for all or part of an anatomical bone element, for example an implant made of metal or alloy of metal, ceramic, polymer, or any other biocompatible material.

According to one embodiment, the subject of the invention is a surgical implant for fixing at least two adjacent bone elements of a patient, consisting of a rod intended to be inserted into a borehole made in the at least two elements. adjacent bone, said implant being characterized in that the stem is curved and hollow so as to form a cavity substantially along the axis of the rod and open at its distal end, said rod comprising at least one deployable anchoring means capable of protruding between a retracted position and a deployed position outside the rod once the latter is placed in the bore so as to immobilize said implant.

By "rod" is meant a solid element, preferably of cylindrical shape and which constitutes the body of the implant according to the invention. By "curve" is meant a shape describing or comprising a flat arc or three-dimensional portion, not necessarily regular. The stem may be of regular or mixed curved shape. When it is regular, the stem has a regular arc of curvature, that is to say that it corresponds to a regular circular arc over its entire length. We will then speak of "curvature" or "regular arc of curvature". When it is mixed the stem has a straight part and at least a curved part without the stem necessarily presents symmetry. In some embodiments, the composite rod may have two, three or more curved portions. We will then speak of "curvature" or "mixed arc of curvature". "Hollow" means that the rod comprises over all or part of its length a bore in the longitudinal direction so as to form a cavity, said cavity being open on one end of the rod (so as to introduce an ancillary for example by this open end). According to a particular embodiment, the cavity is open at the so-called "rear" or "distal" end of the stem, the other end, called "before" or "proximal" being full and may have a pointed shape intended to facilitate the penetration of the stem within the bone elements.

By "deployable anchoring means" means any means known to those skilled in the art that can move from a position called "retracted", that is to say not hinder in any way whatsoever insertion or withdrawal by sliding of the rod within the hole provided for this purpose to a so-called "extended" position, that is to say projecting outwardly of the rod so as to come s anchor in the bone and immobilize the implant.

In a preferred form, said deployable anchoring means can easily move from the retracted position to the deployed position, and vice versa, so as to insert or remove the rod at the convenience of the surgeon for example. According to a preferred embodiment, the "retracted" position means inside the cavity of the stem. By way of non-limiting example, the anchoring means may consist of a protuberance, a stop, a hook, a ring, a relief, an impression, a fin, or any equivalent means. According to one particular form of the invention, the deployable anchoring means consists of a rigid element such as, for example, a rigid fin capable of being deployed towards the outside of the rod. In other words, the present invention relates to an implant which as described above is characterized in that said at least one deployable anchoring means consists of at least one fin.

According to a preferred form of the invention, said at least one fin is integral with the rod by one of its hinge sides with the body of the rod.

Still according to a preferred form, said at least one fin may have a chamfer or a rounded in its upper distal portion which comes into contact with the bone or any general shape favoring the passage from the extended position to the retracted position by pressing the bone on the wing when the rod is removed.

According to another preferred form of the invention, said at least one deployable anchoring means consists of a rigid element such as, for example, a rigid pin capable of being deployed towards the outside of the rod. According to one embodiment, the implant may comprise several deployable anchoring means arranged on all or part of the rod. It is understood that depending on the nature of the bone elements to be sealed, the arrangement of said deployable anchoring means may be adapted according to the general knowledge of the skilled person. For example, in the case of a use for securing two vertebrae, the rod according to the invention may comprise two sets of deployable anchoring means, each series may comprise at least two means arranged near the distal end of the stem for the first and near the proximal end of the rod for the second. In this way, the means of anchoring once deployed will be anchored in bone without any contact with the intervertebral space.

According to a preferred form, the stop of said at least one deployable anchoring means which comes into contact with the bone can be sharp or slightly sharp so as to enter the bone without damaging it.

The surgical implant according to the invention is particularly suitable when said bone elements are vertebrae. The shape of the rod determines the shape of the implant, so in a particular embodiment the rod is curved and the surgical implant once it is in place is also curved. In a specific embodiment, the stem is curved in different planes. According to another additional characteristic, the shape of the surgical implant is mixed, that is to say that it has one or more straight portions and one or more curved portion (s).

The curvature of the implant according to the invention is therefore not necessarily regular. The curvature of the implant according to the invention is therefore not necessarily regular. According to one particular form of the invention, the implant according to the invention will comprise at least one regularly curved portion preferably of developed length between 20 and 180 mm describing an arc of radius typically between 60 and 150 mm. According to a more preferred form of the invention perfectly adapted to the joining of two vertebrae in an adult patient, the stem is of curved shape in a plane, with a developed length of 70 mm describing an arc of 44.6 ° and of constant constant radius. at 90mm. According to an additional feature the rod is made of metal or a metal-based alloy. In another embodiment the rod is made of materials different biocompatible so as to have according to its sections properties, including flexibility different. Of course, in specific embodiments, different surface treatments of the rod may be envisaged to ensure the biocompatibility, the cutting edge, the spring effect, the sliding or, on the contrary, the adhesion of one or other of these elements.

The biocompatible materials constituting the deployable anchoring means may be identical to those used for the rod.

The present invention therefore relates to an implant as described above which is characterized in that the rod constituting it is made of one or more biocompatible materials which are flexible. When the rod is made of a rigid material, the surgeon must drill into the bone elements to assemble which curvature is identical to that of the rod. When the rod is made of a solid but flexible material, the rod is capable of adapting to any curvature of the drilling performed by the surgeon according to predefined parameters. Thus, according to an additional characteristic, the rod is made of one or more flexible biocompatible material (s). The rod may in particular have a nail shape. According to a particular embodiment, the implant according to the invention is characterized in that only some of the portions of the rod are flexible.

In general, whatever the shape of the implant according to the invention, it may be envisaged to make only certain portions of the rod of a flexible material. For example, the flexible portions may be provided to be positioned outside the bone elements to be assembled, for example two vertebrae, so as to form a kind of hinge and maintain some flexibility in the implant.

The simplicity of this surgical implant makes it particularly adaptable to the morphology of the adjacent bone elements to be fixed between them. Indeed, it is easy to manufacture "custom-made" surgical implants of substantially curved shape, having a symmetry or not with respect to said curve, etc. All forms are permitted in the present invention depending on the area to be implanted. For implantation at the vertebral level, for example, a curved surgical implant will be preferred in order to adapt to the morphology of the vertebrae and to their articulation. The curvature is then determined according to the morphology of the bone elements to be joined. The curvature of the implant according to the invention will not necessarily be flat and may present twists. The curvature of the implant according to the invention is not necessarily regular.

Typically, for an adult patient, the stem has a diameter of between 4 and 8 mm, preferably around 6 mm. The establishment of the surgical implant therefore requires drilling of equal or slightly greater size, such as for example between 5 and 10 mm in diameter.

As indicated above, according to a preferred embodiment, the deployable anchoring means are arranged, in their retracted position, within a cavity made for this purpose in the rod. Thus, during the establishment of the rod, they do not hinder the establishment of the rod. An alternative embodiment may be that for example said deployable anchoring means is "plated" against the outer wall of the rod (which may include an imprint for this purpose). Any other equivalent embodiment will of course have to be considered to be within the scope of the present invention.

The transition from the "retracted" position to the "deployed" position, and vice versa, can be achieved by any technique known to those skilled in the art. In concrete terms, any technique making it possible to apply pressure to the deployable anchoring means can be envisaged, said pressure then pushing the deployable anchoring means so that they deploy from the "retracted" position into the cavity from the rod to the "extended" position then forming a projection outside the rod.

According to one embodiment, it may be envisaged to inject a fluid under pressure, such as pressurized air, into the cavity.

According to other embodiments, it may be envisaged to use spring or elastic mechanisms.

According to another preferred embodiment, it will be used a movable male element capable of sliding in the cavity of the rod so that the head of said movable male member abuts against the deployable anchoring means and thus of push them to deploy to the outside of the rod for example in the manner of a screw in ankle.

According to a preferred embodiment the implant further comprises an insertable movable male element within the cavity of the stem, after it has been inserted into the bone elements to be stabilized so that the head of said movable male element comes from abut against the deployable anchoring means and thus push them to project outwardly of the rod. According to the embodiment chosen, and as will be described in more detail later, this male element mobile may be left in place and participate in the rigidity of the implant or may be removed.

In a first alternative, this mobile male element can be considered as an integral part of the implant according to the invention.

In a second alternative, this movable male element may be considered as not forming an integral part of the implant according to the invention but as constituting an independent ancillary. Accordingly, although the description below applies more particularly to the second alternative, it is to be understood that the invention is directed to both the integrated embodiment in which the implant comprises a rod forming the body of the implant and a movable male element, but also the "kit of part" mode which comprises an implant consisting of the rod and an independent ancillary consisting of said movable male element, the assembly forming a kit according to the invention.

The present invention therefore also relates to an assembly or kit which comprises an implant as described above and an ancillary comprising a hollow body with a proximal end adapted to be fixed on the distal end of the rod and a male element mobile slidable within said hollow body and capable of sliding in the cavity of the rod so that the head of said movable male member abuts against the deployable anchoring means and thus allows to push them to make them protrude outside the stem.

Preferably, said movable male element consists of two portions, a distal portion intended to be removed after implant placement and a proximal portion intended to remain in place within the cavity of the stem in order to maintain pressure. on the means anchor so as to keep them in the "deployed" position. In this embodiment, the removal of the proximal portion of the movable male member will cause a passage from the "deployed" position to the "retracted" position of the anchoring means, thereby allowing removal of the implant by a simple traction of the surgeon.

According to another particular embodiment of the invention, it is envisaged an assembly or kit which comprises an implant as described above and an ancillary as described above comprising a movable male element consisting of two portions, a distal portion to be removed after implant placement and a proximal portion to remain in place within the stem cavity to maintain pressure on the anchoring means to maintain them in the "deployed" position.

By way of nonlimiting example, as will be illustrated below in the figures, it may be used an ancillary type "syringe" consisting of i) a rigid body or semi rigid with an end adapted to come cooperate with the distal end of the rod and the other end being open and ii) a movable male member slidable within said body in the manner of a piston, said movable male member may comprise two portions.

The invention also provides a method of attaching at least two adjacent bone elements, implementing

the surgical implant according to the invention, consisting of:

- perform a drill with the characteristics defined by the surgeon according to the bone elements to

solidarity,

- insert the rod into the well, then

- Deploying said at least one deployable anchoring means. According to a particular embodiment, the present invention relates to a method of fixing at least two adjacent vertebrae which implements a surgical implant as described above, said method consisting in: - practicing with the aid of a drilling tool having the characteristics defined by the surgeon according to the vertebrae to be joined, then

inserting the rod into the bore thus made using a medical radioscopic laying tool, then deploying said at least one deployable anchoring means by applying pressure on said at least one anchoring means; so as to slide it from a "retracted" position to a "deployed" position.

According to a more particular embodiment, the present invention relates to a method of fixing at least two adjacent vertebrae which implements a surgical implant as described above, said method consisting in: practicing with the aid of a tool drilling a drill having the characteristics defined by the surgeon according to the vertebrae to be joined, and then

inserting the rod in the borehole thus made using an ancillary device as described above comprising i) a rigid or semi-rigid hollow body with an end adapted to cooperate with the distal end of the stem and the another end being open and ii) a movable male element sliding inside said body in the manner of a piston applying a pressure on the movable male element so that the latter is inserted into the cavity made for this purpose in the rod, slides along the rod so as to abut on said at least one deployable anchoring means thus applying a pressure on this last so that it can move from the "retracted" position to the "deployed" position.

According to a still more particular embodiment, the present invention relates to a method of fixing at least two adjacent vertebrae which implements a surgical implant as described above, said method consisting in:

- Using a drilling tool, drill a drill with the characteristics defined by the surgeon according to the vertebrae to be joined, then

inserting the rod in the borehole thus made using an ancillary device as described above comprising i) a rigid or semi-rigid hollow body with an end adapted to cooperate with the distal end of the stem and the another end being open and ii) a movable male element consisting of a distal portion and a proximal portion detachable and sliding within said body in the manner of a piston

applying a pressure on the movable male element so that the latter comes to fit within the cavity formed for this purpose in the rod, slides along the rod so as to abut on the at least one deployable anchoring means thereby applying pressure thereon so that it can move from the "retracted" position to the "deployed" position

- Removing the distal portion of the movable male element so that only the proximal portion remains within the cavity of the rod in order to pressure said at least one deployable anchoring means.

When the surgeon deems it applicable according to the bone elements to be assembled and the material constituting the stem, it may be envisaged to use a drilling and laying tool which uses the rod forming the surgical implant. having a pointed distal end as a drill head. In this embodiment there is no prior drilling step when the method according to the invention is applied.

It will be readily understood that the rod of the implant according to the invention can be inserted as a nail by simple percussion or any other thrust on its outer end, without it being necessary to print any rotational movement. The rod of the implant according to the invention can even be inserted in this way in a borehole or housing having a certain curvature, which is strictly impossible for a traditional rigid screw. If the drilling has a constant radius of curvature and lying in a single plane, that is to say without torsion, the rod of the implant according to the invention may be rigid but must have the same radius of curvature as said drilling. If the bending radius of curvature is not constant or if it has one or more twists the stem of the surgical implant according to the invention must necessarily have a certain flexibility. The features of the invention mentioned above, as well as others, will appear more clearly on reading the following description of an exemplary embodiment, said description referring to the attached figures, among which: FIG. longitudinal sectional view of the rod (4) constituting the surgical implant with the deployable anchoring means (8) in the "retracted"position; Figure 2 shows a longitudinal sectional view of the rod (4) constituting the surgical implant with the deployable anchoring means (8) in the "deployed"position; 3 shows a view of the implant in a conventional embodiment with the rod (4) at the moment when it will be inserted in the borehole (5) made in two vertebrae adjacent (2; 3) with the deployable anchoring means (8) in the retracted position. Also shown is an ancillary device consisting of a rigid hollow body (11) whose proximal end (12) is positioned at the open distal end (7) of the rod (4) and a movable male element (13) in two portions (13 ';13'') in the high position; Figure 4 shows the rod (4) forming the implant placed in the borehole (5) with the ancillary in place, the movable male element (13) still in the high position. The arrow shown in this figure illustrates the pressure that will be exerted by the surgeon on said movable male element (13); 5 represents the implant anchored within the adjacent bone elements (2; 3) with the movable male element (13) completely inserted into the cavity (6) of the rod (4) thus projecting the means of anchoring (8) to the outside of the rod (4) as represented by the arrows.

This example of placement of an implant according to the invention describes the joining of two adjacent vertebrae (2; 3) by means of a surgical implant as described above. The embodiment illustrated in Figures 1 and 2 shows a rod (4) of curved shape with a regular curvature arc.

More particularly, there is shown in Figure 1 a surgical implant according to the invention consisting of a rod (4) curved and hollow so as to form therein a cavity (6) open at its distal end (7). . In this embodiment, the proximal end is solid and is in the form of a tip. The rod (4) shown comprises in this embodiment 4 deployable anchoring means (8) consisting of fins shown in the retracted position inside the cavity (6). Figure 2 illustrates the implant according to the invention comprising said 4 deployable anchoring means (8) shown in the deployed position. As is clear from this figure, the fins constituting the deployable anchoring means (8) protrude towards the outside of the rod (4) so as to be anchored directly within the bone material constituting the elements. to join. In this figure or in FIG. 1, there is also shown an embodiment with the distal end (7) open so as to allow a fluid or an ancillary to be inserted within the cavity (6). ) in which the fins (8) are retracted and thus press on the latter to deploy them. According to the embodiment shown, the fins (8) have a base stop of a length (X) greater than the length (Y) of the stop which comes into contact with the bone.

Figure 3 shows an embodiment of the implant according to the invention. It is shown the stem (4) curved and hollow with within it a cavity (6) in which are folded the fins (8) forming anchoring means deployable. The rod (4) is shown while it will be inserted into the bore (5) made for this purpose by the surgeon within the two bone elements (2; 3) to be secured. In this embodiment, the rod (4) is shown as being introduced and pushed into the bore (5) via an ancillary. As indicated above, the use of such an ancillary is in no way limiting and should be considered as a form of the invention. The ancillary comprises a rigid or semi-rigid hollow body (11) forming a tube, with a proximal end (12) adapted to cooperate with the distal end (7) of the rod (4) and the other end being open from to receive a movable male element (13) slidable within the cavity formed by said hollow body (11), in the manner of a piston. The male element mobile (13) consists of a distal portion (13 ') to be removed which constitutes the portion thereof and a proximal portion (13'') intended to remain inserted within the cavity (6) of the stem (4). For the sake of clarity, the distal portion (13 ') is shown hatched with spaced lines while the proximal portion (13'') is shown hatched with narrow lines. The hollow body (11) is shown in white section (no filling). In a preferred form, the proximal end (12) is adapted to engage or "clip" on the distal end (7) of the shaft (4). According to another embodiment, the proximal end (12) has a diameter slightly greater than the diameter of the distal end (7) of the rod (4) so as to be able to position itself by covering around said distal end ( 7) of the rod (4). In practice, the surgeon can set up the ancillary once the rod (4) installed in the borehole (5) or use the ancillary as a tool to push the rod (4) and thus insert it completely into the drilling (5). A combination of these two uses may of course be made by manual insertion of the rod (4) and subsequent push with the ancillary.

Figure 4 shows the rod (4) once positioned within the two vertebral bodies (2; 3) to be secured. As is apparent from this figure, the rod (4) is completely inserted into the bore (5) and only the ancillary positioned at the distal end (7) of the rod (4) is outside the vertebrae . At this stage, the movable male element (13) is in the upper position, that is to say engaged within the rigid body (11) forming the ancillary but not extending beyond the proximal end (12) . Thus, at this stage, the movable male element (13) is in no way engaged within the cavity (6) of the rod (4). In the shown mode, the proximal portion (13 '') is completely inserted within the hollow body (11) while the distal portion (13 ') is not. As also illustrated, the surgeon will only have to apply pressure to the movable male member (13) as shown by the arrow. Such a pressure will have the effect of introducing the proximal portion (13 '') of the movable male element (13) into the cavity (6) of the rod (4) while the distal portion (13 ') is inserted into the hollow body (11). The end of the proximal portion (13 '') will thus abut on the fins (8) which are retracted within the same cavity (6). Under this pressure, the fins (8) will be propelled outwardly of the rod (4) so as to be anchored directly in the bone material forming the vertebrae (2; 3). In this embodiment applied to the joining of two vertebrae, it is illustrated the wings (8) forming anchoring means retracted within the rod (4) and arranged to be positioned at the central bone portion forming each vertebra. Preferably, no fin is disposed at the intervertebral junction.

Figure 5 shows the surgical implant in its final position within two vertebral bodies (2; 3) in our example. The fins (8) are deployed (as illustrated by the arrows in the drawing) so as to be securely anchored in the vertebrae. The pedicles of the vertebrae are not affected by the placement of the surgical implant, which avoids any problem of false path and / or nerve or vascular injury. All that remains is for the surgeon to remove the ancillary device with the distal portion (13 ') of the movable male element (13). In this embodiment, the proximal portion (13 '') will be disengaged from the distal portion (13 '), the proximal portion (13'') remaining inserted into the stem (4) so as to maintain pressure on the fins (8). Although not represented, it is easily understandable that the surgeon can easily remove the implant using the ancillary. The latter will be returned to position at the open distal end (7) of the rod (4) so as to allow the distal portion (13 ') of the movable male element (13) to become solid with the proximal portion (13 '') of the movable male element (13) remained in place within the cavity (6) of the rod (4). The surgeon will then only have to remove the movable male element (13) in its entirety. This will have the effect of removing the pressure exerted by the proximal portion (13 ") on the fins (8) and thus allow them to return to the retracted position in order to remove the implant.

When the surgeon deems it applicable according to the bone elements to be assembled and the material constituting the rod (4), it may be envisaged to use a drilling and laying tool which uses the stem (4) of the surgical implant presenting a pointed distal end as a drill head. In this embodiment there is no prior drilling step when the method according to the invention is applied. This method is particularly suitable for the fixation of several adjacent vertebrae in a patient presenting a lumbar problem requiring the intervention of a surgeon because it avoids the insertion of pedicle screws according to the techniques currently used, which is less invasive and greatly limits the side effects related to the vertebral fixation operation. In addition, the operation can be considered spine closed under fluoroscopic control, passing between the nerve bundles and without damaging the nerves. First, a borehole (5) is made with a first drilling tool. Then a tool of pose, which one can not consist of the ancillary, is used in order to place the stem (4) since the cortex through the soft part of the first vertebral body and finally to the second vertebral body to fix. Secondly, the fins (8) forming deployable anchoring means are deployed by any technique known to those skilled in the art. The present invention also relates to kits or kits containing the equipment necessary for the implementation of the method described above.

According to a first embodiment, the present invention relates to kits or kits containing a surgical implant in one of the embodiments detailed above.

According to a second embodiment, the present invention relates to kits or kits containing a surgical implant in one of the embodiments detailed above and an ancillary in one of the embodiments detailed above.

In a preferred embodiment the kit or kit includes a curved surgical implant and an ancillary kit.

According to a third embodiment, the present invention relates to kits or kits comprising a surgical implant in one of the embodiments detailed above, an ancillary in one of the embodiments detailed above, and a drilling tool and / or a tool for laying the rod (4) independent of the ancillary.

Claims

Surgical implant for fixing at least two adjacent bone elements (2; 3) of a patient, consisting of a rod (4) intended to be inserted into a borehole (5) made in the at least two elements adjacent bone (2; 3), characterized in that said rod (4) is curved and hollow so as to form a cavity (6) substantially along the axis of the rod (4) and open at its distal end ( 7), said rod (4) comprising at least one deployable anchoring means (8) able to slide between a retracted position and a deployed position outside the rod (4) once the latter has been put in place. drilling (5) so as to immobilize said implant.

2. Surgical implant according to claim 1, characterized in that said at least one deployable anchoring means (8) consists of at least one fin.

3. Surgical implant according to any one of the preceding claims characterized in that the rod (4) is made of one or more biocompatible materials which are flexible.

4. Surgical implant according to any one of the preceding claims characterized in that the portions of the rod (4) positioned outside the bone elements (2; 3) to be assembled are flexible.

5. Surgical implant according to any one of claims 1 to 4 characterized in that it further comprises a movable male element (13) insertable within the cavity (6) of the rod (4) so that the head of said movable male element (13) abuts against the deployable anchoring means (8) and thus push them to project outwards from the rod (4).

Implant according to claim 5, characterized in that said movable male element (13) consists of two portions, a distal portion (13 ') intended to be removed after implant placement and a proximal portion (13' ') intended to remain in place within the cavity (6) of the rod (4) in order to maintain pressure on the anchoring means (8) so as to keep them in the "deployed" position.

Kit comprising a surgical implant according to any one of claims 1 to 6.

Kit according to claim 7, characterized in that it comprises an ancillary device consisting of a hollow body (11) with a proximal end (12) adapted to be fixed on the distal end (7) of the stem (4) and a movable male element (13) slidable within said hollow body (11) and able to slide within the cavity (6) of the rod (4) so that the head of said movable male element (13) abuts against the deployable anchoring means (8) and thus push them to project outwardly of the rod (4).

A method of attaching at least two adjacent bone members (2; 3) comprising:

- Drilling (5) having the characteristics defined by the surgeon according to the bone elements (2; 3) to be joined,

- insert the rod (4) in the borehole (5) thus made, then - Deploying said at least one deployable anchoring means (8).

A method of attaching at least two adjacent vertebrae (2; 3) comprising:

- Using a drilling tool, drill (5) having the characteristics defined by the surgeon according to the vertebrae (2; 3) to be joined, and then

inserting the rod (4) in the borehole (5) thus made using an ancillary including i) a hollow body (11) with a proximal end (12) adapted to cooperate with the distal end (7); ) of the rod (4) and the other end being open and ii) a movable male element (13) consisting of a detachable distal portion (13 ') and a proximal portion (13' ') and sliding within said hollow body (11)

applying a pressure on the mobile male element (13) so that the latter comes to fit within the cavity (6) formed for this purpose in the rod (4) and slides along the rod ( 4) so as to abut on said at least one deployable anchoring means (8) thereby applying a pressure on the latter so that it can pass from the "retracted" position to the "deployed" position

- unhooking the distal portion (13 ') of the movable male element (13) so that only the proximal portion (13) remains within the cavity (6) of the rod (4) in order to put pressure on said at least one deployable anchoring means (8).