Source: https://patents.google.com/patent/WO2002003882A2/en
Timestamp: 2019-10-18 22:41:12
Document Index: 33214136

Matched Legal Cases: ['art 14', 'art 14', 'art 14', 'art 14', 'art 42', 'art 42']

WO2002003882A2 - Shock-absorbing intervertebral implant - Google Patents
WO2002003882A2
WO2002003882A2 PCT/FR2001/002261 FR0102261W WO0203882A2 WO 2002003882 A2 WO2002003882 A2 WO 2002003882A2 FR 0102261 W FR0102261 W FR 0102261W WO 0203882 A2 WO0203882 A2 WO 0203882A2
PCT/FR2001/002261
WO2002003882A3 (en
2000-07-12 Priority to FR00/09093 priority
2001-07-12 Application filed by Spine Next filed Critical Spine Next
2002-01-17 Publication of WO2002003882A2 publication Critical patent/WO2002003882A2/en
2002-05-23 Publication of WO2002003882A3 publication Critical patent/WO2002003882A3/en
150000003377 silicon compounds Chemical group 0 description 1
The invention concerns an intervertebral implant comprising a wedge designed to be pressed between two spinous processes of two vertebrae. The wedge comprises two elements (10, 12) made of a first material, having a first end (10a, 12a) and a second end (10b, 12b), said first end (10a, 12a) capable of being secured to a spinous process, and, a linking piece (14) made of a second material with greater elastic deformability than said first material, linking said second ends (10b 12b) of said two elements (10, 12) so that the loads exerted on said two elements (10, 12) are absorbed, whereby said intervertebral implant is adapted to limit and brake the relative movement of said vertebrae.
The present invention relates to an intervertebral implant intended to apply in particular between two spinous processes of two vertebral fibers.
The indications for which this type of implant is inserted and fixed between the spinous processes usually originate from the degeneration of the intervertebral disc. Indeed, when the posterior part of the intervertebral disc is degraded, in particular, the spine extension causes the abnormal approach of the two vertebrae separated by the disc. This approximation generally means pinch the nerve roots and the emergence of pain in the subject is affected by the disorder.
Intervertebral implant comprising a wedge inserted between the spinous processes and comprising attachment means are well known. Holds, generally consist of a titanium alloy, have a groove at each of their ends, so that the spinous processes are secured in the grooves. Furthermore, maintaining the hold is provided by a link connecting the two opposite edges of each of the grooves and partially enclosing the wall of the spinous processes.
Such implants are used to limit the approximation of the vertebrae because when the spine is in extension, the spinous processes tend to abut against the bottom of the opposite grooves in which they are introduced. However, the material from which is made the wedge is hard in relation to the disc material that limits the approximation of the vertebrae when intact so that the shock waves that may be transmitted to the spine, when walking for example, are not damped between two vertebrae connected by the wedge. Moreover, the shim does not have identical mechanical properties in the remaining portion of the intervertebral disc, the overall mechanical properties of the spine have significant discontinuities in the light of an intact spine, which increases the intervertebral disc degeneration.
An object of the present invention is to provide an intervertebral implant with two opposed grooves against which the spinous processes come into abutment have a relative mobility and whose relative movements are damped.
To achieve this object, according to the invention, the intervertebral implant comprising a spacer intended to be applied between two spinous processes of two vertebrae, characterized in that said wedge comprises:
- two elements consisting of a first material having a first end and a second end, said first end being securable to a spinous process, and - a connecting piece made of a second material of greater elastic deformability than said first material, connecting said second ends of said two elements so that the stresses which are exerted on said two elements are damped, whereby said intervertebral implant is adapted to limit and brake the relative movement of said vertebrae.
Thus, the connecting part between the two elements, each secured to a spinous process, tends to be compressed when the spinous processes move toward and to absorb the stresses exerted on said two elements. In this way, alignment of the vertebrae takes place with a certain elasticity that is close to the natural elasticity conferred an intact intervertebral disc. In addition, the elastic relative mobility of the vertebrae is compatible with the elastic deformation of posterior ligaments that maintain the vertebrae together. One then obtains a system whose relative mobility, under constraints, constituent elements is substantially identical to the relative mobility of the elements of the original system intact, preserving those elements of the progression of degeneration.
Advantageously, said second ends of the wedge have a fastening wall to which said connecting piece is capable of adhering. Thus, no additional fixing member is needed, and adhesive properties of the second material cooperating with the connecting wall.
In a particular implementation of the invention said fastening wall has recesses adapted to cooperate with asperities on said connecting piece so as to increase adhesion of said connecting part on said wall. It will be understood that to provide recesses in a wall increases the surface thereof, thereby increasing the contact surface between the two materials if one of the materials can be molded on the wall of the other. Increasing the contact surface induces the increase in bond strength between said connection piece and said two elements. In addition, recesses are practiced so as to increase the contact surface and to correspondingly increase the static frictional forces of the material of the connecting piece on said two elements, these forces are adding to the bonding forces.
Advantageously, said second material of said connection piece is constituted by a body obtained by polymerization. In this way, the connecting piece can easily be molded in melt on said elements if the material is polymerized in advance, or it may be formed in situ if the polymerization rate of the monomers constituting said second material is sufficiently low for sufficient time necessary to the realization of the assembly.
In a preferred implementation of the invention, said first material of said elements is a titanium alloy. Thus, it is easy to provide recesses in said wall for securing on which said connecting piece is capable of adhering. According to a first particular embodiment, each first end of said two elements forms a notch defining two wings, suitable for receiving a spinous process and in that said implant further comprises an adjustable length link interconnecting said two wings, said tie surrounding a portion of said spinous process so as to secure said first end to said spinous process.
Thus, this feature of the intervertebral implant is in the mode of attachment of said elements on the spinous processes. Said link is pre-installed on said elements of said shim, and when the latter is inserted between two processes, the clamping of the link allows the fastening of said elements to the apophyses.
According to a second particular mode of implementation of the invention, each first end of said two members form a groove suitable for receiving a spinous process, said groove defining two wings, and in that said implant further comprises a stem adapted to pass through laterally said wings and said apophysis so as to secure said first end to said spinous process.
In this configuration, the spinous processes are pierced transversely and the elements connected thereto by means of a pin or rivet which passes through both the two wings of the element and the mastoid between the two. The stem or the rivet is fastened on one of the wings or both so preventing accidental withdrawal.
According to a third particular embodiment of implementation of the invention, each first end forms a groove suitable for receiving a spinous process, said groove defining two wings, and said implant further comprises a clip-forming semicircular part interconnecting said wings, said clip surrounding a portion of said spinous process so as to secure said first end to said spinous process. In this way, the staples are readily attachable to the wings of said elements, after inserting the shim. As explained in more detail, according to this particular mode of implementation, the wings being released, the insertion of the wedge is performed without major intervention on the posterior ligaments.
Other features and advantages of the invention will become apparent from reading the description below of particular embodiments of the invention, indicative but not limiting, with reference to the accompanying drawings wherein:
- Figure 1 is an axial sectional view of an intervertebral spacer according to the invention, - Figure 2 is a schematic elevation view showing the intervertebral implant fitted with its adjustable fixing links,
- Figure 3 is a schematic elevation view showing the intervertebral implant fitted with fixing pins, and,
- Figure 4 is a schematic elevation view showing the intervertebral implant fitted with mounting clips
By first referring to Figure 1 will be described the block and the binding mode of the elements that constitute it.
The intervertebral implant comprises two symmetrical members 10 and 12 each having a first end 10a and 12a and 10b and a second end 12b. The two elements 10 and 12 are made of a bio-compatible material of the type titanium alloy, so as to be permanently installed inside the body on the spine.
Each first end 10a, 12a has a groove 10'a,
12'a wherein a spinous process is capable of bearing, such that each first end 10a, 12a substantially surrounds half the circumference of an apophysis, the latter passing completely through the first end 10a, 12a.
The elements 10 and 12 are connected by a connecting piece 14, interposed therebetween, so that said elements 10 and 12 are held symmetrically with respect to one another. It is precisely the second ends 10b and 12b of the elements 10 and 12 which are interconnected.
The connecting piece 14 consists of a body obtained by polymerization of the plastic types. This body is selected from materials whose elastic deformability is greater than that of the material of said elements 10 and 12 and especially whose elastic properties are in the order of those properties of the posterior ligaments which hold the various elements of the spine.
Organic silicon compounds form polymers whose mechanical properties are likely to be determined by the choice of basic compounds, in particular in their degree of substitution, the nature of the substituents and their molecular weight, and which elastic behavior is preponderant relative to plastic behavior. Thus, they constitute a family of materials suitable for the realization of the connection between said two elements 10 and 12. Furthermore, these polymers may have a high adhesiveness to the mineral composition of materials. Thus, when the elements 10 and 12 are made of titanium alloy, the connecting piece 14 ensures a good securing. However, the used polymer type materials are not limited to organosilicon compounds and any other material having similar properties could be used.
The material of said connecting piece 14 is capable of adhering to a connecting wall of said second ends 10b and 12b substantially flat. However, in order to increase the adhesiveness, recesses 16 are formed in the connecting wall of the ends 10b and 12b and are adapted to cooperate with asperities 18 of the connecting piece 14 which are inserted in the recesses 16.
This feature allows, on the one hand to increase the contact surface between the two materials and thus to increase the bonding strength between them in a direction normal to said contact surface, and secondly to create forces static friction that add to the adhesion strength.
Such a connection is carried out either by injecting the hot polymer between the two elements 10 and 12 maintained facing in a mold, or molding the mixture of cold monomers between the two elements 10 and 12 if the reaction rate is slow enough . Thus, projections 18 are they formed in situ when the polymer in the liquid or pasty phase, inserted into the recesses 18, solidifies after cooling or after chemical reaction. It is understood that the connecting part 14 is constituted by the polymer interposed between the elements 10 and 12 and to maintain between these elements facing when in the liquid state, the walls of the mold must necessarily surround the space separating the two elements 10 and 12 in their extension.
According to a particular embodiment, not shown, the recesses 16, formed in the wall of interlocking, open into the outer wall elements 10 and 12 so that the polymer in the liquid phase penetrates fully into the recesses 16 without air can be imprisoned. In this way, the connection between the material of the connecting piece 14 and the elements is enhanced. Furthermore, the recesses, shown parallel to the longitudinal axis of the wedge in Figure 1, may be formed obliquely to said longitudinal axis and / or non-rectilinear. These configurations make it possible to increase the static friction forces of the polymer on the elements 10 and 12 which strengthens their connection. According to another embodiment of the invention, not shown, the elements 10 and 12 are drilled axially in the fastening wall of their second ends 10b and 12b to form a single recess opening in its first end 10a and 12a at the bottom of their throat 10'a and 12'a. A portion of the bore forming recess located close to the groove has a larger diameter than the bore which opens into the wall fastening, so as to form a shoulder. Thus, the connecting piece is molded between the elements 10 and 12 so that the polymeric material penetrates into the two recesses and completely fills up the bottom surface of its groove 10'a and 12'a. In addition, the diameter of the bores is greater than the diameter of the recesses illustrated in Figure 1. Thus, after the polymeric material has regained its solid state, not only secures the two elements 10 and 12 by its adhesive properties on inner walls of the bores, but also secures it mechanically as parts of molded material in said portions of larger diameters abut against said shoulders.
Referring now to Figures 2, 3 and 4 to describe particular modes of implementation of the invention.
Figure 2 illustrates a first particular implementation of the invention in which the two opposite edges of the grooves 10'a and 12'a form wings 20, 21, 22, 23 connected in pairs by links 30 and 32, the portion of length between said wings 20, 21 and 22, 23 can be adjusted and locked by the voltage which is capable of applying on said links 30 and 32 is found in Figure 2 the two elements 10 and 12 connected by the connecting part 14. the implant according to the invention is inserted between two spinous processes 34, 36 of two adjacent vertebrae so that the two grooves 10'a and 12'a located opposite enclose partially the respectively underlying portion of the upper spinous process 34 and the overlying portion of the lower spinous process 36.
The links 30 and 32 respectively overlap the overlying portion of the upper spinous process 34 and the underlying portion of the spinous process 36 so that the spinous processes 34 and 36 are adapted to be locked respectively in the grooves 10 'a and 12'a. Blocking is effected by the clamping links 30 and 32 which by means of slots in the flanges 21 and 23, get stuck in the said wings 21 and 23.
Thus, 10 and -12 elements are integral with the two processes 34 and 36 and the relative movement of said processes 34, 36 is possible within the limits of deformation of the connecting part 14 in the polymeric material.
When the two spinous processes 34 and 36 approach each other, especially during extension of the spine, the two elements 10 and 12 compress the connecting part 14 resiliently, that is to that the force which tends to move away from one another the spinous processes 34 and 36 is substantially proportional to the relative displacement of the two processes. Thus, the implant allows to supply the intervertebral disc or part of the intervertebral disc on the spacing that keeps between two vertebrae in order not to get any root. It also provides the stresses applied to the spinous processes that are compatible with the stresses exerted by the posterior ligaments of the processes.
In addition, when the two spinous processes 34 and 36 move away from each other during the flexion of the spine, the linking part undergoes a traction whose restoring force is substantially proportional to the elongation that it undergoes, at least for low amplitudes. Thus, bending of the spine is carried out with a greater amplitude than that permitted with the fastening fixedly, two spinous processes. Figure 3 illustrates a second particular embodiment of implementation of the invention in which the wings of the grooves and the spinous process which is inserted between the two are locked together by a rod passing therethrough.
Is found in Figure 3 the intervertebral spacer between the two spinous processes 34 and 36 and the pairs of wings 20, 21 and 22, 23 which enclose partially the processes 34 and 36. In addition, grooves 10'a and 12 ' has are traversed by a rod 40 which also passes through the spinous processes 34 and 36. the wings 20, 21 and 22, 23 are respectively pierced with two orifices facing through which the stem 40 is adapted to be inserted and fixed by its ends . In prior to insertion of the implant between the spinous processes 34, 36 are pierced laterally past an orifice whose diameter is greater than the diameter of the rod 40. Next, the intervertebral spacer is inserted between the spinous processes 34 , 36, then the rod 40 forming rivet is slid so as to pass through the wings 21, 20 and 22, 23 as well as the spinous processes 34, 36 corresponding. The ends of rods 40 are crushed longitudinally so as to give them a larger diameter than the orifice of the wings 21, 22, and 22, 23 through which they pass. In this way, the rods 40 are blocked in longitudinal translation vis-à-vis the spacer and thus the two elements 10 and 12 are respectively secured to the spinous processes 34 and 36.
According to this second particular embodiment of the invention, there is no need for removal of the interspinous ligaments or the avulsion of the supraspinatus ligament underlying and overlying the intervertebral space in which the wedge is inserted. Indeed, upon insertion of the wedge, the pairs of wings 20, 21 and 22, 23 not being interconnected by means adapted to surround the spinous process, only required the removal of the interspinous ligaments and disinsertion of the supraspinatus ligament of the intervertebral space in which the wedge is inserted.
Figure 4 illustrates a third implementation mode of the invention providing the same advantages as those described above for the second implementation mode.
Is found in Figure 4 the intervertebral spacer between the two spinous processes 34 and 36 and the pairs of wings 20, 21 and 22, 23 which enclose partially the processes 34 and 36. However, the elements 10 and 12 of the wedge intervertebral are made integral, the spinous processes 34 and 36 respectively, by means of a semicircular piece 42 forming clip.
This part 42 comprises two semicircular hook ends directed inwardly of the part suitable for being fitted in openings in the outer wall of the pairs of wings 20, 21 and
22, 23. The part 42 is elastically deformable so that it is fixable in force on the elements 10 and 12.
After the wedge has been inserted between the spinous processes 34, 36, the clip 40 are fixed to the elements 10 and 12 so that the inner wall parts semicircular 42 covers a wall portion of the spinous processes, complementary to the portion wall of the spinous processes covered by the grooves 10'a and 12'a. Thus, the spinous processes 34 and 36 are immobilized in grooves 10'a and 12'a by the clips 42, 10 and 12 making them integral with said spinous processes elements.
The embodiments and implementation of the invention described above are not only limited to an intervertebral implant adapted to be interposed between two adjacent vertebrae. So it is not outside the scope of the invention by providing an implant consisting of two implants as described above together with the end of their wings along their longitudinal axis so as to limit and dampen the relative movement of three vertebrae consecutive.
1. An intervertebral implant comprising a spacer intended to be applied between two spinous processes (34, 36) of two vertebrae, characterized in that said wedge comprises:
- two elements (10, 12) consist of a first material having a first end (10a, 12a) securable to a spinous process (34, 36) and a second end (10b, 12b) having recesses (16); and - a connecting piece (14) made of a second material of greater elastic deformability than said first material, connecting said second ends (10b, 12b) of said two members (10, 12), said connecting piece having asperities (18) may be inserted into said recesses (16), so as to increase the adhesion forces between the connection piece and said two elements, whereby said intervertebral implant is adapted to limit and brake the relative movement of said vertebrae.
2. An intervertebral implant according to claim 1, characterized in that said recesses (16) and said protrusions (18) with which they cooperate are oriented substantially parallel to the longitudinal axis of said shim.
3. An intervertebral implant according to claim 1 or 2, characterized in that said second material of said connection piece (14) is constituted by a body obtained by polymerization.
4. An intervertebral implant according to any one of claims 1 to 3, characterized in that said first material of said elements (10, 12) is a titanium alloy.
5. An intervertebral implant according to any one of claims 1 to 4, characterized in that each first end (10a, 12a) of said two members (10, 12) forms a groove (10'a, 12'a) defining two wings (20, 21, 22, 23) suitable for receiving a spinous process (34, 36) and in that said implant further comprises a longitudinally adjustable link (30, 32) interconnecting said two wings (20, 21; 22, 23), said link (30, 32) surrounding a portion of said spinous process (34, 36) so as to secure said first end (10a, 12a) to said spinous process (34, 36).
6. An intervertebral implant according to any one of claims 1 to 4, characterized in that each first end (10a, 12a) of said two elements forms a notch (10'a, 12'a) adapted to receive a spinous process (34 , 36), said groove defining two wings (20, 21, 22, 23), and in that said implant further comprises a rod (40) adapted to laterally through said wings (20, 21, 22, 23) and said process (34, 36) so as to secure said first end (10a, 12a) to said spinous process (34, 36).
7. An intervertebral implant according to any one of reven- dications 1 to 4, characterized in that each first end (10a,
12a) forms a groove (10'a, 12'a) adapted to receive a spinous process (34, 36), said groove (10'a, 12'a) defining two wings (20, 21, 22, 23), and in that said implant further comprises a semicircular member (42) forming a clip connecting said flanges (20, 21, 22, 23), said clip (42) surrounding a portion of said spinous process (34, 36) so as to secure said first end (10a, 12a) to said spinous process (34, 36).
PCT/FR2001/002261 2000-07-12 2001-07-12 Shock-absorbing intervertebral implant WO2002003882A2 (en)
US11/800,676 Continuation US7666228B2 (en) 2000-07-12 2007-05-07 Shock-absorbing intervertebral implant
WO2002003882A2 true WO2002003882A2 (en) 2002-01-17
WO2002003882A3 WO2002003882A3 (en) 2002-05-23
WO2005110258A1 (en) * 2004-05-17 2005-11-24 Wooridul Spine Health Institute Co. Spine insert
WO2006015500A1 (en) * 2004-08-13 2006-02-16 Synthes Gmbh Intervertebral implant
BR112012020550A2 (en) * 2010-03-04 2017-06-27 Synthes Gmbh expandable laminar implant for spinal fusion.
2001-07-12 US US10/332,412 patent/US7238204B2/en not_active Expired - Fee Related
FR2811540B1 (en) 2003-04-25
US8216274B2 (en) 2012-07-10 Longitudinal member for use in spinal or trauma surgery and stabilization device with such a longitudinal member
US10314620B2 (en) 2019-06-11 Vertebral support device
KR101559857B1 (en) 2015-10-13 Rod-Shape Implant in Particular for the Dynamic Stabilization of the Spine
KR100953145B1 (en) 2010-04-16 Anchoring means for intervertebral implants
CN100438834C (en) 2008-12-03 Posterior vertebral support assembly
CN101686842B (en) 2012-10-03 Inter-spine vertebral implant
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