Source: https://patents.google.com/patent/EP1532949B1/en
Timestamp: 2019-10-15 18:01:13
Document Index: 243790348

Matched Legal Cases: ['application no. 6', 'art 120', 'art 130', 'art 120', 'art 130', 'art 120', 'art 130', 'art 130']

EP1532949B1 - Expandable intervertebral fusion cage - Google Patents
Expandable intervertebral fusion cage Download PDF
EP1532949B1
EP1532949B1 EP20030026820 EP03026820A EP1532949B1 EP 1532949 B1 EP1532949 B1 EP 1532949B1 EP 20030026820 EP20030026820 EP 20030026820 EP 03026820 A EP03026820 A EP 03026820A EP 1532949 B1 EP1532949 B1 EP 1532949B1
EP20030026820
EP1532949A1 (en
Soo-kyung 112-204 Kaepo Woosung 7cha Apt. Chae
Jae-Ryoun Youn
Do-heum 1-908 Ssangyong Apartment Yoon
Yong-eun 601-203 Cheonggu Apartment Cho
Sang-taek 3-1006 Samik Apartment Kim
Kyungwon Medical Co Ltd
2003-11-20 Application filed by Kyungwon Medical Co Ltd filed Critical Kyungwon Medical Co Ltd
2003-11-20 Priority to EP20030026820 priority Critical patent/EP1532949B1/en
2005-05-25 Publication of EP1532949A1 publication Critical patent/EP1532949A1/en
2007-07-18 Publication of EP1532949B1 publication Critical patent/EP1532949B1/en
The present invention relates to an expandable interfusion cage according to the preamble of claim 1.
Several techniques are known at present for restoring a normal lumbar lordosis in this way, by implanting either a graft which in time fuses the vertebrae together, or a prosthesis which fixes them together immediately, while maintaining the possibility of achieving a fusion between the vertebrae in time.
In the second above-mentioned technique, use is made mainly of implants, also known as "cages", some of which are hollow, rigid, and contain only one piece, with inside/outside intercommunication slots for receiving a bone graft which, via said slots, subsequently fuses with the adjacent vertebrae on either side. In this field, reference can be made to International Patent Publication No. WO 96/08205 published on March 21, 1996 for an "Intervertebral fusion cage of conical shape", and European Patent Publication No. EP 637 440 published on February 8, 1995 for an "Intersomatic implant for the spinal column". Nevertheless, cages of those types are of outside dimensions that are given and fixed, whereas the distances between pairs of vertebrae are not constant. In addition, the inclinations of the facing vertebral faces to which a given angular position is to be imparted do not enable rigid cages to be used from a posterior direction. That is, they can be inserted only from an anterior direction.
Such cages or implants are described, for example, in European Patent Publication No. EP 664 994 published on August 2, 1995 , entitled "Vertebral intersomatic cage" or in France Patent Publication No. 2 719 763 published on November 17, 1995 , entitled "Vertebral implant".
In an effort to address this problem, an expandable osteosynthesis cage is disclosed in International Publication No. WO 1998/10722 dated March 19, 1998 and in US patent application no. 6,129,763 . In this regard, referring to Figs. 1 and 2, the cage 1 has a hollow shape and includes a seat 7 and branches 5. The seat 7 serves as a cylindrical body and is pierced by an orifice 8. Each of the branches 5 is connected at one end thereof to the seat 7. A spacer 2 is movably assembled in an inside volume 9, that is, an inside space, of the cage 1. As the spacer 2 is moved toward the distal ends of the branches 5, the branches 5 are biased radially outward by the spacer 2 and thereby expanded.
The expandable osteosynthesis cage partially solves the defects occurring in the conventional art, but some of the defects still remain. In particular, while the spacer 2 is movably assembled in the inside space having a tapered section, if the spacer 2 is moved to the distal ends of the branches 5 to bias radially outward the branches 5, positioning of the spacer 2 at the distal ends of the branches 5 is structurally unstable.
An object of the invention is to provide an expandable interfusion cage by which stable movement of the spacer during expansion of the cage is obtained.
The object of the present invention has been achieved by an expandable interfusion cage having the features of claim 1.
Fig. 3 is an exploded perspective view illustrating an expandable interfusion cage not forming part of the present invention;
Fig. 4 is a perspective view illustrating an assembled state of the expandable interfusion cage not forming part of the present invention;
Fig. 6 is a cross-sectional view illustrating an operating state of the expandable interfusion cage not forming part of the present invention;
Fig. 7 is a perspective view illustrating an assembled state of a variation of the expandable interfusion cage not forming part of the present invention;
Figs. 8a through 8c are perspective views illustrating variations of a spacer used in the expandable interfusion cage not forming part of the present invention;
Fig. 9 is an exploded perspective view illustrating an expandable interfusion cage in accordance with the present invention; and
Fig. 10 is a perspective view illustrating an active position of the expandable interfusion cage according to the present invention.
Fig. 3 is an exploded perspective view illustrating an expandable interfusion cage not forming part of the present invention; Fig. 4 is a perspective view illustrating an assembled state of the expandable interfusion cage not forming part of the present invention; Fig. 5 is a cross-sectional view taken along the line A-A of Fig. 4; and Fig. 6 is a cross-sectional view illustrating an operating state of the expandable interfusion cage not forming part of the present invention.
As shown in Figs. 3 through 6, an exemplary expandable interfusion cage comprises a cage body 100, a spacer 200 and a plug 300. The cage body 100 may be formed to have a quadrangular or cylindrical shape as shown in Figs. 7 or 3, respectively. The cage body 100 is composed of a seat part 120 and a branch part 130. As best shown in Fig. 3, the seat part 120 is pierced by an orifice 110 in which the plug 300 is threadedly assembled. A plurality of branches 131 constituting the branch part 130 are integrally formed at their proximal ends with the seat part 120.
In the expandable interfusion cage, constructed as mentioned above, as shown in Fig. 6, as the spacer 200 is inserted into the inside space 100v of the cage body 100 and then moved toward the distal ends of the branches 131 of the branch part 130, the inward projections 131h formed at the distal ends of the branches 131 are engaged into the annular groove 200h of the spacer 200 to be fixedly maintained therein. At this time, as the inward projections 131h are biased radially outward by the spacer 200, the expandable interfusion cage of the present invention is expanded.
Figs. 8a through 8c are perspective views illustrating variations of a spacer used in the exemplary expandable interfusion cage. Referring to Fig. 8a, a spacer 200' has a head portion which possesses a bullet-shaped configuration and a base portion which is formed to serve as an engaging plate 202' possessing a diameter larger than that of the head portion. A plurality of engaging protuberances 201' each having a downwardly inclined face are formed on an outer surface of the spacer 200' directly below the head portion to be spaced apart one from another in a circumferential direction, in a manner such that the inward projections 131h formed at the distal ends of the respective branches 131 are engaged between the engaging plate 202' and the engaging protuberances 201' while expanding the cage body 100 radially outward. Fig. 8b illustrates a spacer 200" which has a quadrangular pyramid-shaped head portion, and Fig. 8c illustrates a spacer 200v which has a conical head portion.
Although it was explained that the cage body has a shape of a hexahedron, a person skilled in the art will readily recognize that the cage body may have a cylindrical or a hexagonal shape while not departing from the scope of the present invention.
Also, while it was explained that the branch part 130 comprises four branches 131, a person skilled in the art will readily recognize that the number of branches is not limited to this and instead six or eight branches can be used to constitute the branch part.
Fig. 9 is an exploded perspective view illustrating an expandable interfusion cage in accordance with the present invention.
As shown in Fig. 9, in an expandable interfusion cage in accordance with the present invention, as in the of the first embodiment, a cage body 100-1 defines therein an inside space 100-1v, and a branch part comprises four elongate branches 131-1. However, the cage body 100-1 of the invention is differentiated from the cage body 100 in that a guiding slit 133-1s communicated with an opening 133-1 is defined between two adjoining branches 131-1 when viewed on distal end surfaces of the branches 131-1 so that four guiding slits 133-1s cooperate to create a cross-shaped space.
In the present invention, a spacer 200-1 comprises a substantially cylindrical spacer body having a head portion 201-1 which is formed as a cross-shaped protrusion of a predetermined size to bias the branches 131-1 radially outward, and a base portion 202-1 which is formed as a disk possessing a diameter larger than that of the head portion 201-1 and has a pair of guide pieces 200-1g oppositely formed at both sides thereof, respectively.
An expanded state of the cage according to the present invention, constructed as mentioned above, is illustrated in Fig. 10. As shown in Fig. 10, in the cage according to the present invention, the spacer 200-1 is movably assembled in the inside space 100-1v which is defined in the cage body 100-1. Then, as the guide pieces 200-1g are moved toward the distal ends of the branches 130-1 to be engaged in two guiding slits 133-1s when viewed at an end of the cage body 100-1 which is opposite to a seat part, the spacer 200-1 biases the branches 130-1 radially outward to allow the cross-shaped head portion 201-1 to expand the cage body 100-1.
Fig. 10 is a perspective view illustrating an active position of the expandable interfusion cage according to the present invention. As can be readily seen from the drawing, even though a substantial load is downwardly applied when the cage is inserted into a vertebra, an expanded state of the cage is stably maintained.
In the present invention, movement of the cage for biasing the inward projections radially outward to expand the cage body is more stably implemented, by which an expanded state of the cage body can be reliably maintained.
An expandable interfusion cage comprising a cage body (100-1) of a quadrangular or cylindrical shape and a spacer (200-1), the cage body (100-1) including a seat part (120) which is pierced by an orifice and a branch part (130) which defines therein an inside space (100-1v) and has a plurality of elongate branches (101-1) integrally formed at their proximal ends with the seat part (120), with an opening (133-1) defined between two adjoining branches (101-1) to communicate with the inside space (100-1v), the spacer (200-1) being movably assembled in the inside space (100-1v) of the cage body (100-1) to expand the cage body radially outward, wherein the spacer (200-1) is engageable with the branches (101-1) while expanding the cage body (100-1),
a guiding slit (133-1s) communicated with the opening (133-1) is defined between two adjoining branches (131-1) when viewed on distal end surfaces of the branches (101-1) so that four guiding slits (133-1s) cooperate to create a cross-shaped space, and wherein the spacer (200-1) comprises a substantially cylindrical spacer body characterized in that the spaces body has a head portion which is formed as a cross-shaped protrusion of a predetermined size to bias the branches (131-1) radially outward, and a base portion (202-1) which is formed as a disk possessing a diameter larger than that of the head portion and has a pair of guide pieces (200-1g) oppositely formed at both sides thereof, respectively.
EP20030026820 2003-11-20 2003-11-20 Expandable intervertebral fusion cage Expired - Fee Related EP1532949B1 (en)
EP20030026820 EP1532949B1 (en) 2003-11-20 2003-11-20 Expandable intervertebral fusion cage
DE2003615037 DE60315037T2 (en) 2003-11-20 2003-11-20 Expandable intervertebral fusion cage
AT03026820T AT367130T (en) 2003-11-20 2003-11-20 Expandable intervertebral fusion cage
EP1532949A1 EP1532949A1 (en) 2005-05-25
EP1532949B1 true EP1532949B1 (en) 2007-07-18
ID=34429418
EP20030026820 Expired - Fee Related EP1532949B1 (en) 2003-11-20 2003-11-20 Expandable intervertebral fusion cage
EP (1) EP1532949B1 (en)
AT (1) AT367130T (en)
DE (1) DE60315037T2 (en)
2003-11-20 DE DE2003615037 patent/DE60315037T2/en active Active
2003-11-20 EP EP20030026820 patent/EP1532949B1/en not_active Expired - Fee Related
2003-11-20 AT AT03026820T patent/AT367130T/en not_active IP Right Cessation
DE60315037D1 (en) 2007-08-30
AT367130T (en) 2007-08-15
EP1532949A1 (en) 2005-05-25
DE60315037T2 (en) 2008-04-24
JP2012040399A (en) 2012-03-01 Flanged interbody fusion device
Inventor name: CHAE, SOO-KYUNG,112-204, KAEPO WOOSUNG 7CHA APT.
Inventor name: PARK, HYUNG-SANG
Inventor name: YOON, DO-HEUM,1-908, SSANGYONG APARTMENT
Inventor name: CHO, YONG-EUN,601-203, CHEONGGU APARTMENT
Inventor name: KIM, SANG-TAEK,3-1006, SAMIK APARTMENT
Inventor name: YOUN, JAE-RYOUN
Ref document number: 60315037