Methods and apparatuses for bone restoration

METHODS AND APPARATUSES FOR BONE RESTORATION

This application claims priority to U.S. Patent No. 10/951,766, filed September 29, 2004, and French Patent No. 04 06211, filed June 9, 2004, the disclosures of which are incorporated herein by reference. Included.

The present invention relates to the field of surgical and medical implants, and more particularly, to an apparatus and method for restoring the anatomical structure of human or animal bone using a medical bone implant.

A variety of causes can cause bone compression, especially in addition to osteoporosis, which causes natural spinal compression by an individual's weight (for example), trauma also causes bone compression, and sometimes the two factors can be combined. This bone compression not only affects the spine, but can also involve other bones, such as the radius and femur.

Several vertebroplasty techniques are known to be effective in correcting the spine, that is, restoring the spine to its original shape or a similar shape. For example, one technique involves inserting an inflatable balloon into the spine and then injecting a compressed fluid into the balloon to apply force to the cortical envelope of the spine, particularly the upper and lower vertebral plateaus, to restore the shape of the spine. This technique is known as kyphoplasty. Once the cortical integument of the bone is corrected, the balloon can be deflated to retrieve it from the spine, and cement can be injected into the cortical integument to provide sufficient mechanical resistance so that the correction is maintained for an extended period of time.

A significant drawback of kyphosis is the number of manipulations, particularly the inflation manipulation, and the need to retrieve the balloon from the patient's body. Also, because the volume of the balloon is multidirectional, the inflation of the balloon is not well controlled, which often results in large pressure acting on the cortical integument in an inappropriate direction. Because of this great pressure, there is a risk of rupture of the cortical cortex, particularly the side of the cortical cortex that connects the upper and lower plateaus of the spine.

There are other spinal implants intended to fill cavities within the spine. However, such implants generally adopt the principle of radial expansion obtained by forming a plurality of points located perpendicular to the longitudinal axis of the implant under the contraction of the longitudinal axis of the implant. In addition, the implants may apply excessively large pressure to each point so that the implant penetrates the material on which the points are supported. Also, similar to kyphosis, very high pressure can cause rupture of the tissue or organ wall, eg, rupture of the cortical envelope. Also, the radial expansion of some implants makes certain directions of expansion not possible.

Embodiments of the present invention reduce the aforementioned disadvantages and provide additional advantages over prior art devices for bone restoration. More specifically, some embodiments of the present invention include a method for restoring an anatomical structure of a human or animal bone, comprising one or more of the following steps.

- introducing the inflatable implant into the bone to be restored, preferably along a unique predetermined single inflation plane of the implant.

- positioning the inflatable implant within the bone such that the inflation surface corresponds to the bone restoration surface.

- Deploying the inflatable implant in the bone restoration plane.

- injecting filling material into and/or around the implant.

Methods according to some embodiments of the present invention create a reinforcing structure that results in a rigid structure (ie, expansion of the implant causes the implant to mix with the cured filling material). In addition, the filling material can be injected with relatively low pressure, since the implant staying in place can maintain the dimensions of the bone structure corrected by the expansion of the implant.

Another feature of embodiments of the present invention is that the inflatable implant may be inflated to a predetermined thickness in the bone restoration plane between a minimum thickness (ie, implant thickness before any expansion) and a maximum thickness (ie, implant thickness after maximum expansion). that there is This feature allows the expansion value of the implant to be controlled, for example for the corresponding spinal correction.

Another advantageous feature of an embodiment of the present invention comprises deploying the inflatable implant by deploying opposing first and/or second plates, which form a first and a second support surface for the bone, respectively. do. This feature can lower the pressure exerted by the implant on the tissue in contact with the implant by increasing the surface of contact or support to the tissue.

Further, the length of the implant may be approximately the same dimension as at least one of the first and second bearing surfaces within the bone. This feature can optimize the ratio of the length of the (tissue) support to the length of the implant. The closer this ratio is to 1, the more likely the implant will be used where a smaller length is required. In addition, this feature makes it possible to inject the filling material at low injection pressures. A low injection pressure is desirable to prevent the filling material from being injected into inappropriate tissue (eg, the walls of a blood vessel).

In another embodiment of the present invention, each of the first and second plates may form a partially cylindrical support surface, a portion (or more thereof) may be parallel to the longitudinal axis of the inflatable implant. A cylindrical support surface (which is a curved surface) may dissipate the force the implant exerts on the tissue.

In another embodiment of the invention, the step of deploying said first and second plates of the implant utilizes one or more supports below said plates. This feature allows the ratio of the length of the support surface to the length of the implant to be large so that it is as close to unity as possible (see the description above). This feature also reduces cantilever beams by allowing the conveying component to be more evenly distributed under the plate.

Filler cements that may be injected into and/or around the implant to provide a compressive load with the implant during the bone restoration process include ionic cements, particularly phosphocalcic cements, acrylic cements or combinations thereof. Thus, the combination of implant and cement is no different from steel reinforced concrete structures in building construction.

In another embodiment of the present invention, an inflatable implant for bone restoration comprises a unique single inflation surface of the inflatable implant. The single inflation surface corresponds to the bone restoration surface. The implant may also include opposing first and second plates, respectively, defining first and second bearing surfaces for the bone. The first plate and the second plate are positioned away from each other along a single inflation plane (eg, when the implant is inflated). The implant may also comprise a first support and a second support for at least one of the first and second support surfaces, the implant preferably being provided (respectively) under one plate or preferably both plates. do. The implant may also include control means for controlling the expansion of the implant. The control means may comprise a material web provided between each support and a corresponding plate, and has a predetermined thickness.

In another embodiment of the present invention, the control means for controlling the expansion controls the inflation value between the minimum thickness of the implant before any expansion of the implant and the maximum thickness of the implant after the maximum expansion of the implant.

Also, (preferably) the implant may comprise means for positioning the inflatable implant within the bone so that the inflatable surface of the implant substantially corresponds to the bone restoration surface. Said means may comprise engaging means (eg threaded engagement means) allowing an angular orientation of the implant about a longitudinal axis, (eg) of the implant for attachment to an implant carrier. It may include one or more planes at the ends.

Further, another embodiment of the present invention relates to a system for bone restoration, which may include at least one inflatable implant having a single inflation surface corresponding to the bone restoration surface (to restore bone more symmetrically). More than one implant may be used within a single bone (see Figure 37). The system may also include a first tube disposed adjacent the outer surface of the bone for restoration, and a first rod having a threaded end for attachment to a distal end within the bone (first rod). may be accommodated inside the first tube). The system may also include a second tube for receiving the first tube therein and a third tube for receiving the second tube therein. The third tube may include one or more coupling members for anchoring the third tube on the outer surface of the bone. The system may also include a drill for forming an enlarged opening in the side of the bone, the drill may be guided by the first rod. The system may also include a medical insertion device for inserting an inflatable implant into a patient.

In another embodiment of the present invention, a medical insertion device for inserting an inflatable implant into a patient is disclosed. The insertion device may include a grip portion having a central bore, a first tube embedded in the central bore, and a threaded rod received in the first tube, wherein the threaded rod is a circle for receiving an implant for insertion into a patient. It may also include an upper end. In addition, the medical insertion device may include a handle attached to the implant carrier and/or the grip part in addition to the gauge for measuring the expansion of the implant.

Other features, advantages, embodiments, and objects of the present invention will become apparent from the following brief description and the following detailed description with reference to the accompanying drawings.

1A is a perspective view illustrating an inflatable implant implemented in accordance with an embodiment of the present invention, in a resting position;

1B is a diagram illustrating the example of FIG. 1A in a deployed/expanded position;

2A is a side view of another inflatable implant implemented in accordance with another embodiment of the present invention, in a resting position;

FIG. 2B is a diagram illustrating the example of FIG. 2A in a deployed/expanded position; Fig. 2c is an enlarged view showing the two supports of Figs. 2a and 2b in the rest position;

Fig. 3 is a side view of the embodiment according to Fig. 1a;

FIG. 4 is a cross-sectional view taken along line II of FIG. 3 .

FIG. 5 is a cross-sectional view taken along line II-II of FIG. 3 .

6 is an end shape of the embodiment according to FIG. 1A as viewed in the F direction.

Fig. 7 is a view from above of the embodiment according to Fig. 1a;

8 is a perspective view of a second inflatable implant implemented in accordance with another embodiment of the present invention, in a rest position;

Fig. 9 shows the embodiment of Fig. 8 in a deployed position;

FIG. 10 is a side view of the embodiment according to FIG. 8 ;

11 is a cross-sectional view taken along line III-III of FIG. 10 .

12 is a cross-sectional view taken along line IV-IV of FIG. 10 .

13 is a cross-sectional view taken along line VV of FIG. 10 .

14 is a cross-sectional view taken along line VI-VI of FIG. 10 .

FIG. 15 is an end shape of the embodiment according to FIG. 8 as viewed in the G direction.

FIG. 16 is a view from above of the embodiment according to FIG. 8 .

17 to 29 schematically show various steps of an embodiment of a method for bone restoration according to the present invention.

30 to 32 schematically show the steps of another embodiment of the bone restoration method according to the present invention.

33 is a perspective view of an implant delivery device for inserting an implant into a patient's bone according to another embodiment of the present invention.

34 is a plan view of the implant delivery device of FIG. 33 .

FIG. 35 is a view illustrating an expansion gauge for the implant delivery device shown in FIGS. 33 and 34 .

FIG. 36 is an expansion value diagram for an implant according to the disclosed embodiment using the implant delivery device shown in FIGS. 33 and 34;

37 is a view showing the use of a pair of implants according to another embodiment of the present invention.

The inflatable implant 1 shown in FIGS. 1A-7 (as well as other embodiments) may comprise one or more of the following.

- Any single inflation surface (2), which may be unique to the implant.

- means (3) for positioning the inflatable implant in the bone, such that the inflation surface corresponds to the bone restoration surface.

- inflation means (4) for deploying the inflatable implant in a single inflation surface (2).

- Control means (5) for controlling a predetermined value of expansion between the minimum thickness (A) of the implant before any expansion of the implant and the maximum thickness (B) of the implant after the implant has been expanded to the maximum (B).

- opposing first and second plates 6 and 7, each capable of forming a first bearing surface 8 and a second bearing surface 9 within the bone, the first bearing surface inside the bone (8) and the second bearing surface (9) are intended to move away from each other along a single inflation surface (2) during the expansion of the implant (1).

As shown in FIGS. 1A and 1B , the implant 1 may comprise a cylindrical shape with a transversely circular outer side, and may include lathe, laser and/or electro-erosion manufacturing techniques (casting). fabrication techniques may also be used) to engineer a biocompatible material to fabricate the tubular body. The implant 1 may also comprise a first end 20 and a second end 21 respectively, each of which has the shape of a transverse cross-sectional shape of a tubular body. The ends are preferably moved towards each other so that the implant can expand, as shown in FIGS. 1B and 2B .

Thus, the two ends 20 , 21 are connected to each other by a first linear arm 22 (also referred to as an upper linear arm) and a second linear arm 23 (also referred to as a lower linear arm), said linear arms being When the implant is not deployed, it is parallel. The linear arms may also be formed longitudinally in a tubular body, ie when the ends 20 , 21 move towards each other under the first plate 6 and the second plate 7 facing each other, the linear arms They can be folded, which also results in the first plate 6 and the second plate 7 facing each other moving away from the longitudinal axis 10 of the tubular body.

Figures 2a to 2c show an embodiment of an implant similar to the embodiment disclosed in Figures 1a and 1b, but with an additional set of supports (eg a four-bar linkage device). More specifically, the implant of FIGS. 2A and 2B includes supports 12A, 12B, 13A, 13B, 14A, 14B, 15A, 15B, consisting of two pairs of supports for each of the upper and lower plates. The additional support may provide greater rigidity to the implant and/or may allow the plates 6 , 7 to deploy reliably approximately parallel and/or horizontally.

As shown in FIGS. 4 and 5 , the linear arms 22 , 23 can be deployed in a single inflation plane 2 (passing the longitudinal axis 10 of the tubular body 24 ) the linear arms 22 , 23 . ) is preferably opposite to each other. In this regard, the linear arms 22 , 23 may be formed from the transverse recesses 40 of the tubular body, which cross the tubular body between the opposite ends 20 , 21 of the implant 1 . It extends over the length of the tubular body. As shown in FIG. 5 , the linear arms 22 , 23 connecting the two ends 20 , 21 each have a transverse cross-section surrounded by an arc 26 of the outer surface of the tubular body. A chord 27 defines an arc 26 and may be included in the wall 25 to form a recess 40 . The recess 40 may be symmetrical with respect to the longitudinal axis 10 .

Each linear arm 22 , 23 may be divided into three continuous rigid body parts and may be articulated (eg) with the ends 20 , 21 as follows. For the upper linear arm 22 , the first rigid portion 28 is connected to the end 20 using an articulation 29 at one end. The other end of the first rigid portion 28 is connected to the first end of the adjacent central second rigid portion 30 using a joint 31 . The second rigid body part 30 may be connected to the third rigid body part 32 using the joint 33 at the second end. The other end of the third rigid portion 32 may be connected with the end 21 using an articulation 34 . Preferably, the joints 29 , 31 , 33 , 34 may each rotate about an axis perpendicular to the inflation surface 2 and have one degree of freedom in movement. Preferably, the joints 29 , 31 , 33 are formed by thinning the walls forming the linear arms in the appropriate articulation area, as shown in FIGS. 1A-3 (see eg 5 and 81 ). is formed

As the ends 20 , 21 of the implant move towards each other, the central rigid portion 30 is pushed by the two adjacent rigid portions 28 , 32 away from the longitudinal axis 10 of the implant. (22, 23) may be developed. 3 , in order for the linear arm to start moving in the correct direction when the ends 20 , 21 move towards each other, the various parts of the linear arm must be properly rotatably connected. desirable.

Thus, the ends of the rigid portions 28, 32 of the upper linear arm 22 may be articulated to the ends 20 and 21, respectively, by a web of material formed in these rigid portions. The other end of the rigid portion 28 , 32 may also be articulated to the central rigid portion 30 by a web of material formed in the rigid portion 28 , 32 . When a force is applied such that the ends 20 , 21 proximate each other along the longitudinal axis 10 of the implant, the displacement of the joint forms a rotating joint in the rigid portion 28 , 32 . This displacement, as a result of movement of the central rigid portion 30 away from the longitudinal axis 10 , tends to cause the rigid portion 32 to pivot toward the outside of the implant.

The lower linear arm 23 may be manufactured in a similar manner to the upper linear arm, and is preferably symmetrical with the upper linear arm 22 with respect to a plane perpendicular to the dilation surface 2 passing through the longitudinal axis 10 .

Therefore, according to some embodiments of the present invention, it is preferable that the joints between the upper linear arm 22 and the lower linear arm 23 and the corresponding rigid parts are formed by a weak portion made by the groove 81 . do. The grooves define a thin web of material (thickness of the material at 31 and 33) forming the tubular body, the thickness of the web of material being able to plastically deform the material without breaking (as shown in the figure). same) may be determined by the depth of the groove 81 . Specifically, according to one embodiment, the rigid parts 28, 32 of the upper linear arm 22 and the symmetrical elements of the lower linear arm 23 may choose a location called extreme expansion, In this position the desired rigid parts are perpendicular to the longitudinal axis 10 of the implant 1 on the ends 20 , 21 being moved towards each other (the rigid part develops upwards to the maximum expansive capacity) and corresponding plasticity changes of the material. causes It is preferable that the width of the groove 81 is predetermined so that there is a gap between the parts of the upper linear arm and the lower linear arm, and an appropriate radius of curvature can be given to the web to ensure plastic deformation without breaking the material. do.

Opposing first plate 6 and second plate 7 may be formed on upper linear arm 22 and lower linear arm 23 . In the upper linear arm 22, for example, the rigid portion 6 is formed by a central rigid portion 30 and a material extension (rigid portions 28 and 32) extending outwardly on both sides of the rigid portion. ] may be formed. To fabricate the rigid plate 6 , the rigid parts 28 , 32 are separated from the upper linear arm 22 using a pair of transverse slots 35 , 36 , each longitudinally along its length. Extend the end part (see FIGS. 3 and 4 ). The joints 31 , 33 and the end parts 28 , 32 form a first support 12 and a second support 13 respectively for the first plate 6 (see FIG. 1b ). The same applies to the second plate 7 by virtue of its symmetry.

Thus, according to the illustrated embodiment, the first plate 6 and the second plate 7 may comprise first cantilever wings 16 and 18 and second cantilever wings 17 and 19 respectively, said The attachments of each cantilever wing are located at the level of the first supports 12 , 14 and the second supports 13 , 15 . 1A-1B , the first cantilever wing 16, 18 and the second cantilever wing 17, 19 have a first plate 6 and a second plate ( 7) may include a length approximately corresponding to the maximum displacement value of one of the

The first plate 6 and the second plate 7 form a first support surface 8 and a second support surface 9, respectively, the length of each of which may be approximately equal to the length of the implant, during expansion It may be displaced perpendicular to the longitudinal axis 10 . According to one embodiment of the invention, since the implant 1 is formed in a tubular body, the first plate 6 and the second plate 7 each form a curved support surface, the support surface being longitudinal It is preferable to be parallel to (10).

The means 3 for positioning the inflatable implant within the bone so that the inflation surface 2 can correspond to the bone restoration surface may include engaging means for enabling angular rotation of the implant about the longitudinal axis 10 . . For example, the engaging means may comprise planes 37 , 38 formed on a cylindrical surface with a circular cross-section of the end 20 , which may enable rotational engagement of the implant 1 . The means (4) for deploying the inflatable implant in a single inflation plane (2) may comprise rigid parts (28, 32) of an upper linear arm (22) and corresponding symmetrical rigid parts in a lower linear arm (23). Also, the first plate 6 and the second plate 7 can be deployed.

The implant carrier 71 (see FIG. 23 ) may be used to bring the ends 20 , 21 of the implant into close proximity to each other when inside the bone. The implant carrier 71 is such that, for example, the end 21 is pulled towards the end 20 by the end 20 supporting the implant and vice versa (eg, End 21 is supported and end 20 is pushed towards end 21]. To this end, the distal end 21 is provided with an orifice 39 at the distal end, for example a threaded opening along the longitudinal axis 10 , for engaging the implant carrier 71 , which is provided with a corresponding screw. includes part. The proximal end 20 may include a bore 80 along the longitudinal axis 10 to allow the central passageway of the implant carrier 71 to pass as far as the distal end 21 .

The control means may be provided by an implant carrier comprising millimetric control means for moving the ends 20 , 21 into close proximity to each other, preferably by means of a screw-screw coupling, which may require Causes the expansion to cease at a specific moment as a function of conditions. On the other hand, the control means 5 may be provided by the articulation of the linear arms 22 , 23 , more specifically by the thickness of the web of material (eg 31 , 33 ), the material The thickness of the web forms a respective linear arm that allows substantially maintaining the predetermined upper deployed position of the linear arm by expansion, irrespective of practically negligible elastic shrinkage.

The deployment of the plates 6 , 7 in the implant, and the stabilization of the plates once deployed, can be achieved by means of the plate by adapting the plates 6 , 7 to the geometry of the bone. In some embodiments of the invention the plates 6, 7 are deployed in parallel arrangement, whereas in other embodiments of the invention if necessary (eg as a function of the bone anatomy) the plates 6 of the implant. , 7) is developed through non-parallel displacement. For example, if the length of each support arm is different, the deployment of the plates 6 , 7 may not be parallel. For example, when the supports 12 and 14 are longer than the supports 13 and 15 (see FIGS. 1A to 2B ), when the implant is deployed, a force is applied to the plates 6 and 7 and gradually tilts away from each other. . 1a to 2b , this results in the plates 6 , 7 moving further away from each other at the end 21 than at the end 20 . Those skilled in the art will understand that, depending on the configuration, it may be necessary to lengthen or shorten only one support each to achieve a particular angle.

Similarly, as shown in Figs. 2a to 2c, the length of a link device composed of four bars comprising supports 12A, 12B, 13A, 13B, 14A, 14B, 15A, 15B is shown. In the same case (i.e., length of 12A = length of 13A, length of 12B = length of 13B, etc.), when the implant expands, it becomes a parallelogram (parallelism between line segments AD and BC is evident, see Fig. 2c). By varying the lengths of L1 and L2, the linkage consisting of four bars does not become a parallelogram when expanded, but rather creates an angle between the plates 6 and 7 . Also, the angle formed may be determined by how closely the ends 20 , 21 are attracted to each other. As the implant is deployed, the angle gradually increases.

8-16 relate to a second embodiment of an inflatable implant 101 , the components of which are functionally similar to corresponding components in the implant of the embodiment shown in FIGS. 1-7 . In addition, corresponding features in FIGS. 8 to 16 related to the embodiment shown in FIGS. 1 to 7 each have the same reference number plus 100, and thus will not be described further.

The illustrated implant 101 differs from the implant 1 in that there are no wing portions in the plates 106 , 107 , as shown in more detail in FIG. 9 . The implant 101 includes a deformable parallelogram system 141 on one of the rigid portions 128 , 132 of each of the upper and lower linear arms 122 , 123 . In the example shown, a parallelogram system is provided on the rigid portion 128 of the upper linear arm 122 and connected to the end 120 , and a corresponding system is provided on the lower linear arm 123 . A parallelogram system may be used to ensure that the respective plates of the linear arms 122 , 123 are displaced parallel to the longitudinal axis 110 of the implant. As shown in the figure, the rigid portion 128 of the upper linear arm 122 is separated (similar to that of the corresponding lower linear arm 123), which forms a deformable parallelogram while the corresponding plate is displaced. It is as if the joints 131 , 129 are (respectively) separated over the end 120 of the implant and over the central portion 130 .

8 to 16 , the joints of the deformable parallelogram 141 may be manufactured in the same manner as the other joints 131 , 133 , and 134 of the upper linear arm 122 . The disclosed geometries as described above and shown in FIGS. 11-14 form a force couple at the various portions 129 , 130 , 132 of the linear arm. This allows for a desired displacement when the ends 120 , 121 of the implant 101 are close to each other.

In order to obtain the deformable parallelogram 141 , the rigid portion 128 of the linear arm consists of three longitudinal levers, namely the two side levers 142 and the central lever forming the two sides of the deformable parallelogram 141 . (143) is preferred. The other two sides of the parallelogram are the central extension 144 of the upper linear arm 122 located on the extension axis of the central lever 143 , and the two side levers extending parallel to the longitudinal axis 110 of the implant. It may be formed by a double extension 145 of the end 120 located on the extension axis of 142 (see FIG. 8 ).

Linear arms ( 122, 123) may be symmetric.

<u>bone restoration example</u>

A first example of a method for human bone restoration according to an embodiment of the present invention using an inflatable implant will now be described with reference to FIGS. 17-29 . More specifically, it relates to a method for restoring the bones of the spine via the posterolateral route while reducing fractures. Accordingly, the method may comprise (preferably all) one or more of the following steps. A person skilled in the art will understand that the implant according to the embodiment of the present invention pushes and divides the tissue inside the bone, preferably such that the support surface of the implant is in contact with the tissue of the bone to be restored.

An inflatable implant, capable of (preferably) inflating in a given single inflation surface 2 (which is inherent to the implant), is introduced into the spine 60 and the shape of the spine is restored. To perform this surgery, a rod/pin 61 (e.g., of the Kirschner pin type) is placed through the skin via the posterolateral route, opposite the cortical bone 64 traversed by the pin. Allows threaded ends 62 to be fixed (eg, screwed) into cortical bone 63 (see FIG. 17 ). The fin 61 is received within the first inflation tube 65 until the end of the first tube 65 contacts (eg, bears) the outer surface of the cortical bone 64 (see FIG. 18 ). .

The first inflation tube 65 is received by the second inflation tube 66 until the end of the second tube 66 contacts (eg, bears) the outer surface of the cortical bone 64 ( 19). Also, the second expansion tube is received by a third expansion tube 67 , which contacts (eg, bears) the outer surface of the cortical bone 64 ( FIG. 20 ). Teeth 68 on the end of the third expansion tube 67 secure the tube to the cortical bone 64 .

As shown in FIG. 21 , the first expansion tube 65 and the second expansion tube 66 are then removed, leaving only the fin 61 surrounded by the tube 67 , which is a tubular spacer. (68) separates them from each other. As shown in FIG. 22 , the proximal cortical bone 64 and the reticular bone 70 are then (eg) pierced using a drill 69 guided by a pin 61 . In one embodiment, the bone of the reticulum is penetrated (almost) to the distal third, after which the drill 69 may be withdrawn (the pin 61 may also be withdrawn).

The proximal end of the implant 1 is then (preferably) detachably attached to the distal end of the hollow core implant carrier 71 introduced into the core of the tube 67 as shown in FIG. 23 . The implant may be detachably attached to the implant carrier via a (for example) threaded coupling. Inside the core of the implant carrier 71 , a rod 72 having a distal end comprising engaging means for engaging the distal end of the implant (and which may also include an inflated proximal end larger than the diameter of the rod). ; indicated by reference numeral 3316 in FIG. 33) may be inserted. Similar to attaching the implant to the implant carrier, the means for coupling the rod to the implant may be through threaded engagement.

The implant carrier 71 as shown in FIG. 33 comprises (eg) adjusting means 3310 for controlling the movement of the rod relative to the implant carrier. Said adjustment means may comprise a grip block 3312, having a central bore, for positioning the implant carrier through said central bore, and at least rotatably but preferably rotatably linearly held in place. do. In this regard, it is preferred that the proximal end of the grip member and the proximal end of the implant carrier are at the same level. The handle 3314 according to one embodiment of the present invention may be attached to the proximal end of one or both of the grip member and the implant carrier, but in either a clockwise or counterclockwise direction relative to the proximal end. It is desirable to rotate freely in both directions. Also, in one embodiment of the present invention, the handle may not be attached to one or both of the grip block and the implant carrier. The handle may include a central opening that preferably includes an internal screw thread of a predetermined thread pitch.

The rod 3316 received within the implant carrier preferably includes a corresponding male thread in thread pitch with respect to the thread of the handle 3314 . The locking mechanism slides against the grip block and may include a pin 3321 that frictionally interferes with the rod 3316 to lock the rod in place (ie, to avoid rotational movement).

The thread of the rod is preferably provided over at least most of the length of the rod. According to one embodiment of the present invention, the rod, implant carrier, grip block and handle may be pre-assembled. The threaded distal end of the rod is inserted into an opening centered at the proximal end of the implant, wherein the distal end may be received in a corresponding threaded portion centered at the distal end of the implant. The distal end of the implant assembly (ie the position of the implant) with the implant carrier/adjusting means may then be inserted into the expansion tube 67 .

34 is another view of an implant carrier, including a gauge 3320 that may be used to indicate the amount of expansion of the implant (eg, as measured according to the amount of rotation of the rod 3316 ). The gauge may include a window to the rod 3316 . 35 , in accordance with one embodiment of the present invention, the visible portion of the rod may not include a screw. Rather, said portion of the rod may include an indicator 3322 indicating the rate of expansion. A marker 3324, additionally provided near the window, allows the user to measure the rate of expansion from relative movement between the two markers.

Depending on the predetermined thread pitch and thread direction of the rod 3316 , the rod 3316 moves in a linear direction relative to the implant carrier when the handle is rotated. Preferably, a screw is provided on the rod so that rotation of the handle clockwise moves the rod outwardly away from the area where the implant will expand (implantation area). For example, for M5 threads, a pitch of 0.8 mm may be used. However, one of ordinary skill in the art will appreciate that (for example) thread pitches of between about 0.5 mm and about 1.0 mm may be used. 36 is a diagram illustrating the load-free expansion of the implant by the number of rotations of the rod for three implants of a specific size according to an embodiment of the present invention.

Accordingly, in view of the embodiments described above, the implant is placed inside the vertebra 60 once positioned within the inflation tube and slid therein. Preferably, the implant is positioned such that a single inflation surface 2 corresponds to a predetermined bone restoration surface (FIG. 24). The position of the implant may be verified using any known imaging technique, such as X-ray and ultrasound.

The handle 3314 is then rotated to "pull" the rod away from the implantation area. Since the proximal end of the implant collides with the implant carrier, pulling out the rod causes the distal end of the implant to move toward the proximal end (or vice versa). This results in the ends of the implant being pulled towards each end to deploy the implant. More specifically, the opposing plates 6 , 7 are deployed and advantageously form a first bearing surface 8 and a second bearing surface 9 respectively inside the spine 60 , and of the opposing plates The surface may be continuous over a length that may be approximately equal to the length of the implant 1 ( FIG. 25 ). In the expansion process, the reduction of fractures is controlled by means of fine control means, for example, achieving the desired expansion by a predetermined value between the minimum thickness of the implant before any expansion of the implant and the maximum thickness of the implant after its maximum expansion. Next, after removing the implant carrier 71 by unscrewing the implant carrier from the implant 1, and pulling out the tube 67 as shown in FIG. 26, only the implant in the deployed position is 60) will remain in place.

Thus, expansion of the implant within the spine is achieved by a support under the plate that allows the transport component to be distributed over the length of the plate under the plate. Thus, the plate may be provided of sufficient length, while limiting the excessive size of the thickness of the plate to resist bending. A person skilled in the art selects the ratio of spatial requirements in terms of length (unexpanded) to the length of the elevated plate for which the implant according to some embodiments of the present invention is extremely optimized, for example it reduces fractures It will be appreciated that from the point of view of the bone, the limited space within the bone can be used favorably.

Further, according to one of the embodiments of the present invention, the rod 3316 may include a disengagement means, which may consist of an internal hex located at the proximal end 3318 of the rod. This allows the rod to disengage from the implant once the implant has been deployed. Alternatively, if the handle is not attached to the grip block and/or implant carrier, the handle may be rotated counter-rotated (ie, rotated so that the rod does not move away from the implant) so that the handle is positioned between the grip block and the implant carrier. moving away from the contact, thereby allowing the handle to engage the proximal end of the rod. Also, reverse rotation of the handle (after deploying the implant) causes the rod to rotate in the same way as the handle, thereby disengaging the rod from the implant. Depending on a given thread pitch, the disengagement can occur at any number of turns (eg, less than or more than one turn). See also FIG. 26 .

Preferably, after the rod is removed, a filler material 74 is injected around the implant. For filling the interior of and around the implant, the filling material may consist, for example, of ionic cements, in particular calcium phosphate-based cements, acrylic cements, or mixtures thereof. To do this, the needle 73 of the injector is slid down the tube 67 until the end of the needle reaches the orifice 39 at the distal end of the implant 1 ( FIG. 27 ). After that, the filling material is injected through the needle. Injections may be made continuously up to the orifice 64 near the cortical bone of the spine 60 in a retrograde manner (FIG. 28). The needle of the injector may then be withdrawn from the tube 67 (FIG. 29).

A second example of the method according to the invention for reconstructing the anatomy of a human bone will now be described with reference to FIGS. 30 to 32 . The above examples generally relate to methods of restoring the bones of the spine by the pedicle route while reducing fractures.

The second example is similar to the first example, and differs from the first example only with respect to the path through which the implant penetrates to the inside of the spine 60 , and the second example is a vertebral body instead of the posterolateral path used in the example of the first method. It is performed in a light manner (FIG. 30). Consequently, only a few steps of the second method are shown in FIGS. 30 to 32 to show the different routes used to introduce the implant 1 into the spine. 30 to 32 , the same elements as those in the example of the first method have the same reference numerals, and the figures correspond to the steps of FIGS. 24, 25 and 28 for the example of the first method, respectively. respond With respect to the step shown in FIG. 32 , the position of the injector needle 73 in FIG. 32 is slightly different from that of FIG. 28 , and in FIG. 32 the position of the injector needle is closer to the distal end of the implant.

Accordingly, it will be seen that the present invention achieves its objectives clearly from the foregoing description. Since certain changes may be made without departing from the scope of the present invention, it is to be understood that all matter contained in the foregoing description or shown in the accompanying drawings is to be understood by way of example and not literally (and thus not to be construed as limiting). do). Those skilled in the art will appreciate that the methods, apparatus, and system configurations shown and described herein are examples of many possible system configurations that are within the scope of the present invention.