Source: https://patents.google.com/patent/EP1857065B1/en
Timestamp: 2019-12-06 13:28:52
Document Index: 247376137

Matched Legal Cases: ['art 12', 'art 12', 'arts 12', 'art 17', 'art 17', 'art 18']

EP1857065B1 - Longitudinal member for use in spinal or trauma surgery - Google Patents
Longitudinal member for use in spinal or trauma surgery Download PDF
EP1857065B1
EP1857065B1 EP06010070A EP06010070A EP1857065B1 EP 1857065 B1 EP1857065 B1 EP 1857065B1 EP 06010070 A EP06010070 A EP 06010070A EP 06010070 A EP06010070 A EP 06010070A EP 1857065 B1 EP1857065 B1 EP 1857065B1
EP06010070A
EP1857065A1 (en
2006-05-16 Application filed by Biedermann Motech GmbH and Co KG filed Critical Biedermann Motech GmbH and Co KG
2006-05-16 Priority to EP06010070A priority Critical patent/EP1857065B1/en
2007-05-11 Priority claimed from JP2007126593A external-priority patent/JP5276799B2/en
2007-11-21 Publication of EP1857065A1 publication Critical patent/EP1857065A1/en
2010-08-25 Publication of EP1857065B1 publication Critical patent/EP1857065B1/en
The invention relates to a longitudinal member for use in spinal or trauma surgery and a stabilization device with such a longitudinal member.
A dynamic stabilization system for segments of the spinal column which comprises a flexible rod made of an elastic material and bone anchors to anchor the rod in the vertebrae is known from EP 1 364 622 A2 , which forms the basis for the two-part form of claim 1, and EP 1 527 742 A1 , respectively. The material of the rod is a biocompatible polymer material, for example a material on the basis of polyurethane. The rod has a corrugated surface with the corrugations extending in a direction transverse to the rod axis.
US 2005/0033295 A1 describes an orthopedic implant that comprises a shape memory polymeric material. The orthopedic implant can be, for example, a spinal rod. It can be molded or fabricated in a desired configuration and can be deformed to a second configuration different from the first configuration. Then, it can be induced, for example by applying heat to revert to its original molded configuration. Above the deformation temperature Td the material is superelastic. The superelasticity is, however, only used for easy deformation of the material into a desired shape. The implant is used to rigidly constrain bony structures.
It is the object of the invention to provide a longitudinal member for use in spinal or trauma surgery and a stabilization device using such a longitudinal member manufacturing which has improved mechanical properties as well as reduced manufacturing costs compared to the known polymer rods.
The object is solved by a longitudinal member according to claim 1 and a stabilization device according to claim 5 and a method according to claim 7. Further developments are given in the dependent claims.
The longitudinal member has the advantage that its tendency to flow when being fixed to the bone anchor is reduced in comparison to the known injection molded elastomer rods. In addition, the longitudinal member in form of the extruded elastomer rod exhibits a lower permanent set, which characterizes the deformation remaining after removal of the deforming stress, and a higher stiffness characterized by the e-modulus compared to the injection molded rod at identical dimensions of the rod. Therefore, under identical load conditions, an extruded elastomer rod with smaller dimensions can be used. Furthermore, the strength against mechanical tensile and/or compressive loads and the abrasion resistance is enhanced. The costs for manufacturing are reduced with regard to the necessary tools and machines which are less expensive compared to the costs for the manufacturing by injection molding.
Fig. 3 shows a perspective view of a rod according to the present invention.
Figs. 6a) to g) show examples of cross-sections of the rod.
Fig. 7 shows a stabilization device for the spinal column including a rod according to the invention and two monoaxial bone screws.
Fig. 8a shows a stabilization device for the spinal column including a rod according to the invention and two polyaxial bone screws.
Fig. 9 shows application of the stabilization device according to the invention to the spinal column for the purpose of correction of scoliosis, wherein the rod according to the invention is in a first, pre-stressed condition.
Fig. 3 to 5 show an embodiment of the invention used as a spinal rod 1. The rod has a substantially circular cross section and a length which is suitable to span a distance between at least two vertebrae. The diameter of the rod can be selected so as to be compatible with that of known metallic spinal rods. In this case, the rod 1 can be connected to known bone screws. In the embodiment shown the cross-section of the rod is constant over the length of the rod.
The rod is made of a biocompatible plastic material which can be molded by extrusion. For example, the material can be a thermoplastic material such as polyaryletheretherketone (PEEK) The material is an elastomer. Suitable elastomers are polyurethane, polycarbonate-urethane (PCU) or silicone. The rod exhibits a three-dimensional elasticity in such a way that a restoring force acts when the rod is put under load which restores the original shape of the rod.
As can be seen in particular in Fig. 3 and 4, the macromolecular construction of the rod 1 is characterized by polymer chains 2 of the elastomer material which are substantially aligned in the longitudinal direction of the rod 1. The macromolecular structure of the rod is therefore substantially uniform in the longitudinal direction. The polymer chains 2 form a fiber-like structure with the fibers oriented in the longitudinal direction, thus being load-oriented.
The rod 1 is preferably manufactured by extrusion. In the well known manufacturing process of extrusion the solid or fluid raw material is filled in an extruder and then pressed through an opening. The parameters such as temperature and pressure during the extrusion process depend on the material used and will be recognized by those skilled in the art.
The rod can have other shapes than a circular cross section. As can be seen in Figs. 6a) to g), different cross sections such as circular (Fig. 6a)), square (Fig. 6b)), rounded square (Fig. 6c)), oval-shaped (Fig. 6d)), rectangular (Fig. 6e)), rounded rectangular (Fig. 6f)) or star-shaped (Fig. 6g)) or triangular are possible. Preferably the cross-section is constant over the length of the rod. With a non-circular cross-section of the rod a rotation of the rod in the bone anchoring element to which it is connected can be prevented. In addition, the shape of the cross-section can be used to achieve bending properties in flexion/extension movement and lateral bending which can differ from each other.
A stabilization device using the rod according to the invention comprises at least two bone anchoring elements for connection of the rod to the bone. As can be seen in Figs. 7 and 8, according to a first example the bone anchoring elements are monoaxial bone screws 10, 10' each comprising a threaded shaft 11 which is to be anchored in a vertebra and a receiving part 12 which is rigidly connected to the threaded shaft. The receiving part 12 has a substantially U-shaped recess to receive the rod 1. A locking element, for example an inner screw to be screwed into the recess or, as shown, an outer nut 13 is provided to fix the rod 1 in the recess. The bone anchoring elements are made of a biocompatible rigid material, for example of a biocompatible metal, such as titanium or a metal alloy.
In use, first, the bone anchoring elements 10, 10' are screwed into the vertebrae which shall be stabilized. Then the rod 1 is inserted into the receiving parts 12 and, after adjustment of its position, fixed in the receiving part by means of the locking element 13. Due to the uniformly aligned macromolecular structure of the rod the tendency to flow under pressure of the locking element is reduced. Therefore, the risk of loosening of the fixation between the rod and the bone anchoring element is reduced. Since the rod exhibits elasticity under flexion, extension and torsion of the spinal segment, the spinal segment can be dynamically stabilized. The elasticity required for a certain application can be obtained by selecting the material and/or the size and/or the shape of the cross-section of the extruded rod.
Fig. 8a shows a second example of a stabilization device using the extruded rod 1. The stabilization device has at least two polyaxial bone anchoring elements 14 and 14' having a threaded shaft 15 to be anchored in the bone and a spherically-shaped head 16 at one end. The head 16 is pivotably held in a receiving part 17 which also receives the rod 1 in a recess. Preferably, a pressure element (not shown) is provided which presses onto the head to fix the head in the receiving part in its angular position. A locking element (not shown) is also provided to fix the rod in the recess.
In use, like in the first example, the bone anchoring elements 14 and 14' are screwed into the vertebrae and thereafter the rod 1 is inserted. Since the head 16 is pivotably held in the receiving part 17 the position of the receiving parts can be adjusted relative to the heads. After adjustment of the position of the receiving parts relative to the heads and of the rod relative to the receiving part, the connection is locked by means of the locking element.
Fig. 9 and 10 show an example of a clinical application of a correction device. The correction device which includes two bone anchoring elements 10 and the extruded rod 1 is applied to a spinal section exhibiting scoliosis. The elastic rod is bent out of its neutral straight shape so as to be adapted to the curvature of the spinal deformity as shown in Fig. 9. By narrowing the distance between the screw heads of the correction device as indicated by the arrows in Fig. 9, a pretension is generated in the rod which urges the deformed part of the spine into a straight position as shown in Fig. 10. For the bone anchoring elements monoaxial or polyaxial screws can be used. Polyaxial screws have the advantage that the shaft and the head can be aligned for receiving the rod.
Fig. 12 shows a modified example of a bone anchoring element with the rod inserted into the recess of the receiving part. The receiving part 18 comprises a recess 19 with a cross-section which differs from the cross-section of the rod. In the example shown the cross section of the recess is oval-shaped while the cross-section of the rod is circular with a diameter smaller that that of the recess. Fixation can be achieved via a locking element (not shown) either directly or with a filling piece (not shown) between the locking element and the rod.
The invention is not limited to the above described embodiments and examples of application. The features of the examples described can be combined with each other. Although the rod is shown to connect two bone anchoring elements, it can have a length sufficient to connect more than two bone anchoring elements. Since the rod is made of an elastomer, the length can be adapted before or at the time of surgery by cutting the rod.
A non isotropic shape for the cross-section, such as for example a rectangular shape, can be used for providing a rod with elastic characteristics which differ dependent on the direction.
With the manufacturing method of extrusion it is possible to produce rods with different shapes and diameters of the cross-section at low costs, since it is not necessary to use complex molds and expensive machines like in the injection molding process.
The invention is also not limited to the application for the spine. The rod can also be used in stabilizing a fractured bone, for example instead of a metallic rod in a fixateur externe or interne.
A longitudinal member (1) for use in spinal or trauma surgery which is sized to span a distance between at least two vertebrae or two bone parts, the longitudinal member exhibiting bending and axial elasticity,
wherein the whole longitudinal member is made of an elastomer material and has a uniform cross-section, and wherein the elastomer material is polyurethane, polycarbonate-urethane (PCU) or silicone.
characterized in that the polymer chains (2) of the elastomer material are substantially aligned in the longitudinal direction of the longitudinal member (1).
The longitudinal member (1) of claim 1, characterized in that it is obtained by extrusion.
The longitudinal member of claim 1 or2, wherein the longitudinal member (1) is a rod.
The longitudinal member of one of claims 1 to 3, wherein the cross-section is substantially circular.
Stabilization device for stabilizing vertebrae or bone parts, comprising
at least two bone anchoring elements having a shaft for anchoring in the bone and a receiving part for connection with a longitudinal member, characterized in that a longitudinal member according to one of claims 1 to 4 is provided for connection with the bone anchoring elements.
The stabilization device of claim 5, wherein the receiving part (12; 17; 18) comprises a recess (19) for receiving the longitudinal member, the cross-section of the part of the recess (19) receiving the longitudinal member being different from the cross section of the longitudinal member.
Method of manufacturing a longitudinal member according to one of claims 1 to 4, characterized by the steps providing the elastomer polymer material and extruding it into the shape of the longitudinal member.
EP06010070A 2006-05-16 2006-05-16 Longitudinal member for use in spinal or trauma surgery Expired - Fee Related EP1857065B1 (en)
EP06010070A EP1857065B1 (en) 2006-05-16 2006-05-16 Longitudinal member for use in spinal or trauma surgery
DE200660016407 DE602006016407D1 (en) 2006-05-16 2006-05-16 Longitudinal part for spine or trauma surgery
ES06010070T ES2351157T3 (en) 2006-05-16 2006-05-16 Longitudinal element to use in spinal or traumatological surgery.
CN 200710102921 CN101073512B (en) 2006-05-16 2007-05-11 Longitudinal member for use in spinal or trauma surgery and stabilization device with such a longitudinal member
JP2007126593A JP5276799B2 (en) 2006-05-16 2007-05-11 Longitudinal material for use in spine or trauma surgery and stabilizing device comprising such a longitudinal material
KR1020070045847A KR101414716B1 (en) 2006-05-16 2007-05-11 Longitudinal member for use in spinal or trauma surgery and stabilization device with such a longitudinal member
TW96116732A TWI398237B (en) 2006-05-16 2007-05-11 Longitudinal member for use in spinal or trauma surgery and stabilization device with such a longitudinal member
US11/749,395 US8216274B2 (en) 2006-05-16 2007-05-16 Longitudinal member for use in spinal or trauma surgery and stabilization device with such a longitudinal member
US13/493,835 US20120277797A1 (en) 2006-05-16 2012-06-11 Longitudinal member for use in spinal or trauma surgery and stabilization device with such a longitudinal member
EP1857065A1 EP1857065A1 (en) 2007-11-21
EP1857065B1 true EP1857065B1 (en) 2010-08-25
ID=37198765
EP06010070A Expired - Fee Related EP1857065B1 (en) 2006-05-16 2006-05-16 Longitudinal member for use in spinal or trauma surgery
US (2) US8216274B2 (en)
EP (1) EP1857065B1 (en)
CN (1) CN101073512B (en)
DE (1) DE602006016407D1 (en)
ES (1) ES2351157T3 (en)
TW (1) TWI398237B (en)
ES2401315T3 (en) * 2009-07-16 2013-04-18 Spinesave Ag Anchoring device for a connecting rod for spine stabilization
2006-05-16 DE DE200660016407 patent/DE602006016407D1/en active Active
2006-05-16 EP EP06010070A patent/EP1857065B1/en not_active Expired - Fee Related
2006-05-16 ES ES06010070T patent/ES2351157T3/en active Active
2007-05-11 TW TW96116732A patent/TWI398237B/en not_active IP Right Cessation
2007-05-11 CN CN 200710102921 patent/CN101073512B/en not_active IP Right Cessation
2007-05-16 US US11/749,395 patent/US8216274B2/en active Active
2012-06-11 US US13/493,835 patent/US20120277797A1/en not_active Abandoned
CN101073512B (en) 2011-02-16
DE602006016407D1 (en) 2010-10-07
US20120277797A1 (en) 2012-11-01
TWI398237B (en) 2013-06-11
CN101073512A (en) 2007-11-21
ES2351157T3 (en) 2011-02-01
EP1857065A1 (en) 2007-11-21
US8216274B2 (en) 2012-07-10
TW200744524A (en) 2007-12-16
US20070270843A1 (en) 2007-11-22
EP2113216B1 (en) 2012-05-30 Rod-shaped element for spinal stabilization and method for producing the same
JP5060041B2 (en) 2012-10-31 Flexible element and stabilizing device used in stabilizing device for bone or verteb
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