2 703 580
`
`
`
`93 02558
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`
`
`11. Publication No.:
`(to be used only for
`ordering copies)
`
`
`
`21. National Registration No.:
`
`51.
`
`
`Int Cl5: A 61 B 17/58
`
`APPLICATION FOR PATENT
`
`A1
`
`
`71. Applicant(s): ROBERT Gilles – FR.
`
`
`
`72. Inventor(s): Robert Gilles and Alby Albert P.
`
`
`
`
`
`FRENCH REPUBLIC
`19.
`______
`
`NATIONAL INSTITUTE OF
`INTELLECTUAL PROPER-
`TY
`______
`
`PARIS
`______
`
`12.
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`
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`22. Date of filing: 03/03/1993
`
`30. Priority:
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`
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`
`
`73. Holder(s):
`
`
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`74. Attorney: de Pastors Alice, Intellectual Property
`Attorney
`
`
`
`
`
`43. Date application made available to the public:
`10/14/1994 Bulletin 94/41
`
`
`56. List of documents cited in the preliminary
`search report: Search report has not been pre-
`pared at the date of publication of the applica-
`tion.
`
`
`60. References to other related national docu-
`ments:
`
`
`
`
`54. Cervical intersomatic cage
`
`
`
`
`57. The invention concerns an element for internal containment
`and intersomatic fusion of vertebrae during discectomy designated
`by the name intersomatic cage.
`
`The characteristics of the cage are as follows:
`
`- Produced from polyethylene or equivalent material, absorb-
`able or not, it introduces a damping factor which reduces the
`transmission of stresses.
`
`- Geometrically the cage is parallelepipedal in shape and may
`or may not include a median reinforcing partition (2). Its anterior
`face (5) and posterior face (6) have heights that are determined to
`ensure preservation of an intervertebral space and a normal lordo-
`sis.
`- The edges of each of the faces of the cage are provided with
`
`ridges (11) intended to resist displacements.
`- Equipped in its central part with a radiopaque marker mak-
`ing it possible to track, over time, the displacement of the implant
`and to enable perturbed radiological and MRI examinations to be
`conducted.
`
`- Volumes available for accommodating osseous fragments of
`appropriate dimensions.
`
`
`.
`
` FR 2 703 580 – A1
`
`DePuy Synthes Sales, Inc. & Depuy Synthes Sales, Inc.
`Exhibit 1012
`1 of 8
`
`

`
`[handwritten:] 1
`
`2703580
`
`
`
`
`
`
`The present invention concerns a containment cage, designated as Intersomatic Cage, which is
`intended to be inserted between two vertebrae. Such insertion makes it possible to support the
`space freed up by the discectomy and to proceed with the installation of a bone graft intended to
`fuse the two vertebrae.
`
`The procedure provides for the following steps:
`1) Access from the anterior face of the cervical spine by incision in a natural skin fold of the
`neck.
`2) Vertical incision on the median line of the prevertebral muscles and installation of a
`transverse self-retaining retractor.
`3) X-ray identification of the exposed disc and installation of pins screwed into the middle
`of the superjacent and subjacent vertebral bodies.
`4) Vertebral distraction and complete discectomy. Abrasion of the anterior lips of the adja-
`cent end plates.
`5) Curettage of the end plates and freshening of the cancellous bone on each intervertebral
`face to favor osteoconduction.
`6) Filling of the cage with two parallelepipeds of cancellous bone extending about 1 mm
`beyond the two faces.
`7) Installation of the cage.
`8) Ablation of the distraction and closure of the incision.
`
`
`Metal implants have the disadvantage of being rigid, resulting in the integral transmission of all
`stresses, and under certain conditions they are an obstacle to good bone remodeling. Moreover,
`they are heavy and cause scanning and MRI artifacts.
`The intersomatic cage, subject of the present invention, provides a solution to these disad-
`vantages.
`
`The characteristics of the cage are as follows:
`- Because it is produced from polyethylene or equivalent material, absorbable or not, the proper-
`ties of the material introduce a damping factor that reduces the transmission of stresses.
`- Geometrically the cage is parallelepipedal in shape. It can have a different shape and may or
`may not have a median reinforcing partition (2). Its anterior face (5) and posterior face (6) have
`heights that are determined to ensure the preservation of an intervertebral space and a normal lor-
`dosis.
`
`5
`
`10
`
`15
`
`20
`
`25
`
`30
`
`DePuy Synthes Sales, Inc. & Depuy Synthes Sales, Inc.
`Exhibit 1012
`2 of 8
`
`

`
`2
`
`2703580
`
`
`
`
`
`
`- The edges of each of the faces of the cage are provided with ridges (11) intended to resist dis-
`placements.
`- Equipped in its central part with a radiopaque marker making it possible to track, over time, the
`displacement of the implant and to enable perturbed radiological and MRI examinations to be
`conducted.
`- Volumes available for accommodating bone fragments of appropriate dimensions, allowing for
`uninterrupted bone communication between the superjacent and subjacent vertebrae, leading to
`intersomatic fusion.
`
`The intersomatic cage is characterized in our case by a particular geometry, illustrated in plate 1/1
`but which is non-limiting, as well as by the fact that plastic material, polyethylene for example, is
`used to produce said cage. Other materials, absorbable or not, having equivalent characteristics
`can be considered. Said material ensures a good mechanical strength of the cage while introduc-
`ing a damping effect which lessens discomfort.
`
`By confining the cancellous bone, the cage favors permanent bone fusion. This is in contrast to
`free insertions of bone part which, because they are not held in place, tend to migrate and to result
`in an imbalance between the faces of the vertebral bodies.
`
`Figure 1 illustrates the non-limiting geometrical characteristics of the cage. Said cage consists of
`an irregular parallelepiped (1) having a median partition (2) serving as reinforcement. Said parti-
`tion in this case defines two receptacles (3) and (4).
`Each receptacle will be equipped with a bone graft at the time of installation. The cage can have a
`different surface for accommodating bones, separations or can be honeycombed.
`The height of the posterior face (6) is sufficient to enable the preservation of a normal cervical
`height. The height of the anterior face (5) is slightly greater to make it possible to obtain the ap-
`propriate degree of lordosis.
`The anterior face includes two holes intended for the installation of the cage by means of a rod
`provided with two retractable nibs. Said rod is represented in figure 2.
`The lateral faces (9) and (10) are in the form of an isosceles trapezoid.
`
`
`
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`5
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`10
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`15
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`20
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`25
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`30
`
`DePuy Synthes Sales, Inc. & Depuy Synthes Sales, Inc.
`Exhibit 1012
`3 of 8
`
`

`
`3
`
`2703580
`
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`The edges of all of the faces of the cage as well as those of the partition are provided with ridges
`(11), the profile of which is designed so as to reduce the risk of secondary displacement.
`Thus the cage will make it possible, after appropriate displacement, for the bone fusion to occur
`under good conditions.
`Moreover, the nonmagnetic properties of the material used for producing the cage will enable
`examinations by scanner or MRI to be conducted without artifacts.
`These examinations are facilitated by the existence of a radiopaque reference incorporated verti-
`cally at the center of the median wall, which will allow any compression or displacement of the
`cage to be quantified.
`
`
`
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`
`
`5
`
`10
`
`DePuy Synthes Sales, Inc. & Depuy Synthes Sales, Inc.
`Exhibit 1012
`4 of 8
`
`

`
`2703580
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`4
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`CLAIMS
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`5
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`10
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`15
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`20
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`25
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`30
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`1) Element for internal containment and intersomatic fusion of vertebrae during discectomy,
`characterized in that it is in the form of a rigid cage-shaped structure intended to confine the can-
`cellous bone.
`
`2) Element for internal containment and intersomatic fusion of vertebrae according to claim 1,
`characterized in that the rigid structure is parallelepipedal in shape.
`
`3) Element for internal containment and intersomatic fusion of vertebrae according to either of
`claims 1 or 2, characterized in that the respective heights of the anterior face (5) and posterior
`face (6) of the cage allow for the preservation of an intervertebral height and a normal lordosis.
`
`4) Element for internal containment and intersomatic fusion of vertebrae according to any one of
`claims 1 to 3, characterized in that the edges of the faces are provided with ridges.
`
`5) Element for internal containment and intersomatic fusion of vertebrae according to any one of
`claims 1 to 4, characterized in that the lateral faces (9) and (10) are in the form of an isosceles
`trapezoid.
`
`6) Element for internal containment and intersomatic fusion of vertebrae according to any one of
`claims 1 to [sic], [characterized] in that the cage is produced from a polymer material, absorbable
`or not, such as nonmagnetic high molecular weight polyethylene, allowing for examinations by
`scanner or MRI without artifacts.
`
`7) Element for internal containment and intersomatic fusion of vertebrae according to any one of
`claims 1 to 6, characterized in that the cage includes a median reinforcing partition, the edges of
`which are provided with ridges.
`
`8) Element for internal containment and intersomatic fusion of vertebrae according to any one of
`claims 1 to 7, characterized in that the volume of confined bone allows for the osseous communi-
`cation between the lower vertebra and the upper vertebra.
`
`
`
`
`DePuy Synthes Sales, Inc. & Depuy Synthes Sales, Inc.
`Exhibit 1012
`5 of 8
`
`

`
`5
`
`2703580
`
`
`9) Element for internal containment and intersomatic fusion of vertebrae according to any one of
`claims 1 to 8, characterized in that it includes a radiopaque marker enabling its position to be
`tracked over time.
`
`
`
`
`
`DePuy Synthes Sales, Inc. & Depuy Synthes Sales, Inc.
`Exhibit 1012
`6 of 8
`
`

`
`
`
`
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`2703580
`
`
`
`
`
`
`
`DePuy Synthes Sales, Inc. & Depuy Synthes Sales, Inc.
`Exhibit 1012
`7 of 8
`
`

`
`DePuy Synthes Sales, Inc. & Depuy Synthes Sales, Inc.
`Exhibit 1012
`8 of 8