U.S. patent application number 14/698295 was filed with the patent office on 2016-11-03 for intervertebral fusion cage.
The applicant listed for this patent is AEGIS SPINE, INC.. Invention is credited to Young-Bo AHN.
Application Number | 20160317320 14/698295 |
Document ID | / |
Family ID | 57136286 |
Filed Date | 2016-11-03 |
United States Patent
Application |
20160317320 |
Kind Code |
A1 |
AHN; Young-Bo |
November 3, 2016 |
INTERVERTEBRAL FUSION CAGE
Abstract
Disclosed is an intervertebral fusion cage which may be inserted
between vertebrae from which a disk is removed to restore and
maintain an interval between two vertebrae, and more specifically,
to an intervertebral fusion cage having an easily mountable shape
while enlarging a contact area with blood in a spinal cavity during
surgery. A intervertebral fusion cage 100 generally includes a
front part 102, first and second side parts 106 and 108 connected
to both ends of the front part 102, and a rear part 104 connected
to the pair of first and second side parts 106 and 108, wherein the
front part 102, the first and second side parts 106 and 108 and the
rear part 104 define fixing holes 130 and 132 therein which are
vertically opened.
Inventors: |
AHN; Young-Bo; (Greenwood
Village, CO) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
AEGIS SPINE, INC. |
Greenwood Village |
CO |
US |
|
|
Family ID: |
57136286 |
Appl. No.: |
14/698295 |
Filed: |
April 28, 2015 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61F 2002/30784
20130101; A61F 2002/4627 20130101; A61F 2002/30538 20130101; A61F
2002/30904 20130101; A61F 2002/30774 20130101; A61F 2/442 20130101;
A61F 2230/0086 20130101; A61F 2/447 20130101; A61F 2/4611 20130101;
A61F 2/4455 20130101; A61F 2002/30556 20130101; A61F 2002/30187
20130101; A61F 2002/30235 20130101 |
International
Class: |
A61F 2/44 20060101
A61F002/44 |
Claims
1. An intervertebral fusion cage comprising: a front part; first
and second side parts connected to both ends of the front part; and
a rear part connected to the pair of first and second side parts,
wherein the front part, the first and second side parts, and the
rear part define fixing holes therein which are vertically opened,
the first and second side parts are formed in a taper decreasing
from the front part to the rear part, a corner insertion part which
is a portion connecting the rear part and the first side part has a
smaller thickness than a portion connecting the rear part and the
second side part, wherein a front corner part connecting the front
part and the second side part has a tool fastening part provided
therein, the tool fastening part is formed in one end of a
reinforcing tube disposed in the fixing holes between a corner
insertion part and the front corner part facing the corner
insertion part, the other end of the reinforcing tube contacts the
corner insertion part, the corner insertion part has a first wedge
seat, and a second wedge seat communicating with the first wedge
seat, and a wedge is inserted in the first wedge seat by pressing
the wedge through inside of the reinforcing tube, the wedge moves
to the second wedge seat to be permanently fixed thereto, such
that, a slit formed in the corner insertion part that is expanded
in a longitudinal direction thereof to increase an entire height of
the corner insertion part in the longitudinal direction
thereof.
2. The intervertebral fusion cage according to claim 1, wherein at
least one of a front corner part which faces the corner insertion
part and connects the front part and the first side part, the front
part, and the first side part has a tool fastening part formed
therein in a lateral direction.
3. The intervertebral fusion cage according to claim 1, wherein a
thickness of the first side part is smaller than a thickness of the
second side part.
4. The intervertebral fusion cage according to claim 2, wherein at
least one of the front corner part, which faces the corner
insertion part and connects the front part and the second side
part, the front part, and the first side part has a flat seat
surface in which the tool fastening part is formed.
5. The intervertebral fusion cage according to claim 1, wherein a
space is defined by the front part, the first and second side parts
and the rear part and is divided into two or more fixing holes by a
reinforcing part, and the fixing holes have a cross-section area or
shape different from each other.
6. (canceled)
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to an intervertebral fusion
cage which may be inserted between vertebrae from which a disk is
removed to restore and maintain an interval between two vertebrae,
and more specifically, to an intervertebral fusion cage having an
easily mountable shape while enlarging a contact area with blood in
a spinal cavity during surgery.
[0003] 2. Description of the Related Art
[0004] A vertebral body includes 32 to 35 vertebrae forming a body,
and intervertebral disks, i.e., spinal disks arranged between the
vertebrae, and is a portion forming a backbone of a human body that
connects an upper skull and a lower pelvis to form the pillar of
the truncus. The spine includes 7 cervical vertebrae, 12 thoracic
vertebrae, 5 lumbar vertebrae, 5 sacra, and 3 to 5 coccyges from
the top. In the case of an adult, 5 sacra are fused together to
form one sacral vertebra, and 3 to 5 coccyges are fused together to
form one tailbone.
[0005] When the intervertebral disc is deteriorated, a prosthesis
referred to as an intervertebral cage is used for restoring a
distance between two adjacent vertebrae. The intervertebral cage
fuses such vertebrae so as not to be moved relative to each other
through the growth of a bone graft inserted into the intervertebral
cage, in an intervertebral cavity.
[0006] Spondylolisthesis refers to a state in which the fourth and
fifth lumbar vertebrae are completely displaced due to a damage
occurred in the vertebral body. In order to treat the
spondylolisthesis, surgery using a so-called anterior lumbar
interbody fusion (ALIF) has been performed. Herein, as a
conventional cage commonly used in the ALIF, a rectangular
box-shaped cage is mainly used. In this case, since the rectangular
box-shaped cage is formed to have a significantly longer lateral
length than a longitudinal length, in order to insert it between
the vertebrae, the surgical site should be largely exposed, and the
disk should be cut in a large region. Therefore, there are problems
of difficulty in the surgery and the process being very
time-consuming.
[0007] In order to solve these problems, a lateral cage has been
developed and used for intervertebral disc surgery (see Korean
Patent Laid-Open Publication No. 10-2011-0013651). However, since
such a lateral cage has a smaller surface area than the ALIF cage,
the contacting area with the blood in the spinal cavity is
decreased, such that a relatively long time is consumed for fusing
the vertebrae, and thereby, a relatively long recovery time is
required for the patient after surgery.
[0008] In addition, the lateral cage is provided with one end
portion which is firstly inserted into the vertebra of the patient
during surgery and has a height formed substantially the same as
the other portions. Therefore, in order to insert the one end
portion of the lateral cage between the vertebrae, there is a need
to apply a great force, and even when being put under an
anesthesia, the pain felt by the patient is large.
[0009] Meanwhile, Korean Patent Laid-Open Publication No.
10-2014-0018668 discloses a cage having a blade mounted and fixed
between intervertebral disks, but this cage still entails the
above-described problems due to a configurational limitation.
SUMMARY OF THE INVENTION
[0010] In consideration of the above-mentioned circumstances, it is
an object of the present invention to provide an intervertebral
fusion cage having an easy mountable shape while enlarging a
contact area with blood in a spinal cavity during surgery.
[0011] In order to accomplish the above objects, according to one
aspect of the present invention, there is provided an
intervertebral fusion cage including: a front part; first and
second side parts connected to both ends of the front part; and a
rear part connected to the pair of first and second side parts,
wherein the front part, the first and second side parts, and the
rear part define fixing holes therein which are vertically opened,
the first and second side parts are formed in a taper decreasing
from the front part to the rear part, and a corner insertion part
which is a portion connecting the rear part and the first side part
has a smaller thickness than a portion connecting the rear part and
the second side part.
[0012] Herein, at least one of a front corner part which faces the
corner insertion part and connects the front part and the first
side part, the front part, and the first side part may have a tool
fastening part formed therein in a lateral direction.
[0013] In addition, the thickness of the first side part may be
smaller than the thickness of the second side part.
[0014] Further, at least one of the front corner part which faces
the corner insertion part and connects the front part and the
second side part, the front part, and the first side part may have
a flat seat surface in which the tool fastening part is formed.
[0015] Further, the space defined by the front part, the first and
second side parts and the rear part may be divided into two or more
fixing holes by a reinforcing part, and the mounting holes may have
a cross-section area or shape different from each other.
[0016] Furthermore, a front corner part connecting the front part
and the second side part may have a tool fastening part provided
therein, the tool fastening part is formed in one end of a
reinforcing tube disposed in the fixing holes between a corner
insertion part and the front corner part facing the corner
insertion part, the other end of the reinforcing tube contacts the
corner insertion part, the corner insertion part has a first wedge
seat into which a wedge is inserted, and a second wedge seat
communicating with the first wedge seat, and a wedge is inserted in
the first wedge seat, and by pressing the wedge through inside of
the reinforcing tube, the wedge moves to the second wedge seat to
be permanently fixed thereto, such that, a slit formed in the
corner insertion part is expanded in a longitudinal direction
thereof to increase an entire height of the corner insertion part
in the longitudinal direction thereof
[0017] The intervertebral fusion cage according to a first
embodiment of the present invention is configured to be inserted
between vertebrae from an anterior side and a lateral side, as well
as an anterior lateral side while having the same surface area as
the conventional ALIF cage, thereby it is possible to insert the
intervertebral fusion cage by properly selecting an insert
direction thereof by an operator as necessary.
[0018] Accordingly, since the vertebrae are fused with an enlarged
contact area with blood in a spinal cavity within a relatively
short time, the intervertebral fusion cage may be easily mounted on
the vertebrae, while providing a significantly reduced recovery
time for the patient.
[0019] In addition, the intervertebral fusion cage according to a
second embodiment of the present invention is configured to be
inserted between vertebrae only from the anterior lateral side, but
by including a device for amending the height of the insertion
portion so as to have the same height as the other portion, the
insertion portion may contact with the vertebra surface to more
decrease the fusing time compared to the intervertebral fusion cage
according to the first embodiment of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] The above and other objects, features and other advantages
of the present invention will be more clearly understood from the
following detailed description taken in conjunction with the
accompanying drawings, in which:
[0021] FIG. 1 is a perspective view illustrating an intervertebral
fusion cage according to a first embodiment of the present
invention as seen from a front thereof;
[0022] FIG. 2 is a perspective view of the intervertebral fusion
cage illustrated in FIG. 1 as seen from a rear thereof;
[0023] FIG. 3 is a plan view of the intervertebral fusion cage
illustrated in FIG. 1;
[0024] FIG. 4 is a schematic view illustrating a state of mounting
the intervertebral fusion cage illustrated in FIG. 1 on a
vertebra;
[0025] FIG. 5 is a perspective view illustrating an intervertebral
fusion cage according to a second embodiment of the present
invention as seen from the front thereof;
[0026] FIG. 6 is a perspective view of the intervertebral fusion
cage illustrated in FIG. 5 as seen from the rear thereof;
[0027] FIG. 7 is a cross-sectional view illustrating the
intervertebral fusion cage illustrated in FIG. 5 and a mounting
tool before fastening; and
[0028] FIG. 8 is a cross-sectional view illustrating a state in
which the mounting tool is fastened to the intervertebral fusion
cage illustrated in FIG. 5, and a wedge is moved by using the
mounting tool.
DETAILED DESCRIPTION OF THE INVENTION
[0029] Hereinafter, the present invention will be described with
reference to the accompanying drawings in detail. Referring to the
drawings, wherein like reference characters designate like or
corresponding parts throughout the several views. In the
embodiments of the present invention, the publicly known functions
and configurations that are judged to be able to make the purport
of the present invention unnecessarily obscure will not be
described.
[0030] The largest configurational characteristic of an
intervertebral fusion cage according to the present invention is
that: it has a taper of decreasing from a high anterior side when
seen from a stomach of a human body to a low posterior side when
seen from a back of the human body; and one end thereof on the
posterior side has a smaller thickness than the other end, so as to
be inserted between vertebrae from an anterior side and a lateral
side, as well as an anterior lateral side, while basically having
the shape similar to the conventional ALIF cage.
[0031] Hereinafter, intervertebral fusion cages 100 and 200
according to first and second embodiments of present invention
having the above-described configurational characteristic will be
described in detail with reference to FIGS. 1 to 8.
[0032] First, the intervertebral fusion cage 100 according to the
first embodiment of present invention will be described in detail
with reference to FIGS. 1 to 4.
[0033] The intervertebral fusion cage 100 generally includes a
front part 102, first and second side parts 106 and 108 connected
to both ends of the front part 102, and a rear part 104 connected
to the pair of first and second side parts 106 and 108, wherein the
front part 102, the first and second side parts 106 and 108 and the
rear part 104 define fixing holes 130 and 132 therein which are
vertically opened.
[0034] The intervertebral fusion cage 100 may be made of polymeric
material which is harmless to a human body such as polyether ether
ketone (PEEK), or formed by coupling a segment of such a polymeric
material and a segment of metallic material with each other.
Herein, the metallic material preferably uses titanium, stainless
steel, or the like which is harmless to the human body.
[0035] The first and second side parts 106 and 108 are formed in a
taper decreasing from the front part 102 to the rear part 104, and
the front part 102, the first and second side parts 106 and 108 and
the rear part 104 have protrusions formed on upper and lower
surfaces thereof so as to prevent the intervertebral fusion cage
100 from sliding by contacting with the surface of the vertebra.
Herein, the protrusions provided on the intervertebral fusion cage
100 according to the first embodiment of the present invention have
a sawtoothed wedge shape which are substantially parallel to the
front part 102 and disposed at a constant interval, but it is not
limited thereto, and may have various shapes. By these wedge-shaped
protrusions, the intervertebral fusion cage 100 may be easily
inserted between the vertebrae, while preventing it from being
separated therefrom.
[0036] In addition, inspection pins 118 and 120 are formed in the
intervertebral fusion cage 100. The inspection pins 118 and 120 are
used for, after the intervertebral fusion cage 100 is mounted
between vertebrae, checking whether it is mounted at a correct
position and alignment by X-ray irradiation. In the first
embodiment of the present invention, two inspection pins 118 and
120 are used, but the number of the inspection pins 118 and 120 may
be increased as necessary. On the other hand, the intervertebral
fusion cage formed of the segment of metallic material as described
above may not be provided with the inspection pin, or may use a
smaller number of inspection pins than the intervertebral fusion
cage made of polymeric material.
[0037] Further, a corner insertion part 128 which is a portion
connecting the rear part 104 and the first side part 106 has a
smaller thickness than a portion connecting the rear part 104 and
the second side part 106. In this case, the corner insertion part
128 is formed so as to be gradually decreased in thickness while
forming a curved surface as illustrated in FIGS. 1 and 2, rather
than decreased in a step shape. Thereby, the intervertebral fusion
cage 100 may be mounted between the vertebrae by inserting the
corner insertion part 128 into a space formed therebetween.
[0038] Additionally, in order to insert the intervertebral fusion
cage 100 from the lateral side through a side of the human body,
the first side part 108 is characterized in that it is formed so as
to have a gradually reduced thickness in an outward direction. That
is, the first side part 108 has a smaller thickness than the second
side part 106. Thereby, the intervertebral fusion cage 100 may be
further easily inserted from the lateral side due the shapes of the
corner insertion part 128 and the second side part 106.
[0039] At least one of a front corner part which faces the corner
insertion part 128 and connects the front part 102 and the first
side part 108, the front part 102, and the first side part 108 has
a tool fastening part 112, 114 or 116 formed therein in a lateral
direction. The tool fastening parts 112, 114 and 116 may have
female screws screwed with male screws formed on a mounting tool
20. In order to stably fix the flexible display unit 20, grooves
are formed in the tool fastening parts 112, 114 and 116 around the
female screws.
[0040] In addition, at least one front corner part which faces the
corner insertion part 128 and connects the front part 102 and the
second side part 106, the front part 102, and the first side part
108 has flat seat surfaces in which the tool fastening parts 112,
114 and 116 are formed. In particular, it is advantageous that the
flat seat surfaces are formed around the female screws and the
grooves of the tool fastening parts 112, 114 and 116 in terms of
the stable coupling with the flexible display unit 20.
[0041] Further, a reinforcing part 110 may be provided in the
fixing holes 130 and 132. The reinforcing part 110 is diagonally
disposed in the fixing holes 130 and 132 between the corner
insertion part 128 and the front corner part facing the corner
insertion part 128. Furthermore, the reinforcing part 110 may be
disposed so as to extend from the front part 102 to the rear part
104 or extend between the first side part 108 and second side part
106 facing with each other. Thereby, the space defined by the front
part 102, the first and second side parts 106 and 108 and the rear
part 104 is divided into the fixing holes 130 and 132 by the
reinforcing part 110. The mounting holes 130 and 132 may have a
cross-section area or shape different from each other, as
necessary.
[0042] According to the first embodiment of the present invention,
by the above-described configurational characteristics, it is
possible to insert the intervertebral fusion cage 100 with the
flexible display unit 20 between vertebrae 10 from any one of the
anterior side, the lateral side and the anterior lateral side, as
illustrated in FIG. 4. Thereby it is possible to insert the
intervertebral fusion cage 100 by properly selecting the insert
direction thereof by an operator as necessary.
[0043] Next, the intervertebral fusion cage 200 according to the
second embodiment of the present invention will be described with
reference to FIGS. 5 to 8. The intervertebral fusion cage 200 is
formed so as to be inserted between vertebrae only from the
anterior lateral side. The components of the second embodiment
having the same configuration as the first embodiment will not be
described.
[0044] The intervertebral fusion cage 200 generally includes a
front part 202, first and second side parts 206 and 208 connected
to both ends of the front part 202, and a rear part 204 connected
to the pair of first and second side parts 206 and 208, wherein the
front part 202, the first and second side parts 206, and 208 and
the rear part 204 define fixing holes therein which are vertically
opened.
[0045] The first and second side parts 206 and 208 are formed in a
taper decreasing from the front part 202 to the rear part 204, and
the front part 202, the first and second side parts 206, and 208
and the rear part 204 have protrusions formed on upper and lower
surfaces thereof so as to prevent the intervertebral fusion cage
200 from sliding by contacting with the surface of the
vertebra.
[0046] In addition, inspection pins 218 and 220 are formed in the
intervertebral fusion cage 200. The inspection pins 218 and 220 are
used for, after the intervertebral fusion cage 200 is mounted
between vertebrae, checking whether it is mounted at a correct
position and alignment by X-ray irradiation.
[0047] Further, a corner insertion part 228 which is a portion
connecting the rear part 204 and the first side part 208 has a
smaller thickness than the portion connecting the rear part 204 and
the second side part 206. In this case, the corner insertion part
228 is formed so as to be gradually decreased in thickness while
forming a curved surface as illustrated in FIGS. 5 and 6, rather
than decreased in a step shape. Thereby, the intervertebral fusion
cage 200 may be mounted between the vertebrae by inserting the
corner insertion part 228 into a space formed therebetween.
[0048] Additionally, in order to insert the intervertebral fusion
cage 200 from the lateral side through a side of the human body,
the first side part 208 is characterized in that it is formed so as
to have a gradually reduced thickness in an outward direction. That
is, the first side part 208 has a smaller thickness than the second
side part 206. Thereby, the intervertebral fusion cage 200 may be
further easily inserted from the lateral side due the shapes of the
corner insertion part 228 and the second side part 206.
[0049] Tool fastening part 214 may be provided in a front corner
part which faces the corner insertion part 228 and connects the
front part 202 and the first side part 208. The tool fastening part
214 may have a female screw screwed with the male screw formed on
the mounting tool 20. A flat seat surface may be formed on the
front corner part around the tool fastening part 114 for stably
coupling with the flexible display unit 20.
[0050] Further, a reinforcing tube 210 may be provided in the
fixing holes corresponding to the fixing holes. The reinforcing
tube 210 is diagonally disposed in the fixing holes between the
corner insertion part 228 and the front corner part facing the
corner insertion part 228. Thereby, the space defined by the front
part 202, the first and second side parts 206, and 208 and the rear
part 204 is divided into the fixing holes by the reinforcing tube
210. The cross-section area or shape of the mounting holes may be
formed different from each other, as necessary.
[0051] The tool fastening part 214 may be integrally formed in one
side of the reinforcing tube 210. In this case, the reinforcing
tube 210 with a thread formed on one end thereof is inserted into
the intervertebral fusion cage 200, such that the thread plays a
role of the tool fastening part 214.
[0052] Preferably, the reinforcing tube 210 has a polygonal shape
so as not to rotate in the intervertebral fusion cage 200. In the
second embodiment of the present invention, the reinforcing tube
210 has a hexagonal cross-section, for example.
[0053] The other end of the reinforcing tube 210 contacts the
corner insertion part 228. In this case, the reinforcing tube 210
may be integrally coupled to the corner insertion part 228 to be
fixed thereto.
[0054] In addition, as illustrated in FIGS. 7 and 8, the corner
insertion part 228 has a first wedge seat 238 into which a wedge
232 is inserted, and a second wedge seat 236 communicating with the
first wedge seat 238, which are formed in one end thereof The
corner insertion part 228 has a slit 230 to be expanded within a
predetermined range in a longitudinal direction thereof
[0055] The reinforcing tube 210 has a longitudinal hole 212 into
which a pressing rod 36 of a mounting tool 30 is inserted. Herein,
the longitudinal hole 212 has a smaller inner diameter than the
outer diameter of the wedge 232 so that the wedge 232 is not
separated from the first wedge seat 238. In one end portion of the
longitudinal hole 212, a wedge rod 234 to which the wedge 232 is
fixed is slidably inserted.
[0056] As illustrated in FIG. 7, the first wedge seat 238, and in
particular, the second wedge seat 236 has a rapidly changed
cross-section, that is, rapidly reduced cross-section area to a
right side in FIG. 7, such that the wedge 232 may be maintained in
a state positioned in the first wedge seat 238. The mounting tool
30 has the pressing rod 36 integrally formed therein and a male
screw 34 formed on one end portion of a mounting tube substrate 32,
which is screwed with a female screw formed in the tool fastening
part 214.
[0057] In addition, as illustrated in FIG. 8, by pressing the wedge
232 through an inside of the reinforcing tube 210, the wedge 232
moves to the second wedge seat 236 to be permanently fixed thereto.
Therefore, the slit 230 is expanded in the longitudinal direction
thereof, and thereby an entire height of the corner insertion part
228 in the longitudinal direction thereof may be increased.
[0058] More specifically, the intervertebral fusion cage 200 is
inserted into the space between the vertebrae during surgery.
Herein, the mounting screw 34 formed on the mounting tube substrate
32 of the mounting tool 30 is screwed with the female screw formed
in the tool fastening part 214. In this state, a force is not
applied to the pressing rod 36 inside of the mounting tube
substrate 32 by an operator. Accordingly, the thickness of the
corner insertion part 228 is smaller than the portion connecting
the rear part 204 and the second side part 206.
[0059] When the intervertebral fusion cage 200 is inserted between
the vertebrae, the wedge 234 of the wedge 232 is pressed by the
pressing rod 36 toward the slit 230. As described above, the wedge
234 integrally formed with the wedge 232 is slidably inserted in
the longitudinal hole 212 of the reinforcing tube 210. In
variation, the wedge 232 may be directly pressed by the pressing
rod 36 while eliminating the wedge 234. By the pressing, as
illustrated in FIG. 8, the wedge 232 moves to the second wedge seat
236 to expand the slit 230, such that the entire height of the
corner insertion part 228 in the longitudinal direction thereof may
be increased. As a result, the corner insertion part 228 also
contacts with the surface of the vertebra to enlarge the contact
area with blood in the spinal cavity, such that the time consumed
for fusing the vertebrae may be decreased, compared to the
lenticular lens sheet 100 according to the first embodiment of the
present invention.
[0060] While the present invention has been described with
reference to the preferred embodiments, it will be understood by
those skilled in the related art that various modifications and
variations may be made therein without departing from the scope of
the present invention as defined by the appended claims.
* * * * *