U.S. patent application number 12/825064 was filed with the patent office on 2010-11-04 for reducing instrument for spinal surgery.
This patent application is currently assigned to WARSAW ORTHOPEDIC, INC.. Invention is credited to David L. Brumfield, Keith E. Miller.
Application Number | 20100280560 12/825064 |
Document ID | / |
Family ID | 36609000 |
Filed Date | 2010-11-04 |
United States Patent
Application |
20100280560 |
Kind Code |
A1 |
Brumfield; David L. ; et
al. |
November 4, 2010 |
Reducing Instrument for Spinal Surgery
Abstract
An instrument is provided for use in orthopedic surgery for
reduction of a connecting member such as a spinal rod toward an
implant such as a bone screw. An embodiment of the instrument
includes handle portions that are pivotable relative to each other
and biased apart, and arm portions pivotable relative to each other
and to the handle portions. Distal portions of the arm portions,
which may be offset from the arm portions, provide structure for
engaging a connecting member and an implant. Squeezing the handle
portions force the distal portions of the arm portions together,
forcing together the connecting member and the implant. A toothed
bar and pawl may be provided to retain the instrument in a squeezed
state.
Inventors: |
Brumfield; David L.;
(Collierville, TN) ; Miller; Keith E.;
(Germantown, TN) |
Correspondence
Address: |
MEDTRONIC;Attn: Noreen Johnson - IP Legal Department
2600 Sofamor Danek Drive
MEMPHIS
TN
38132
US
|
Assignee: |
WARSAW ORTHOPEDIC, INC.
Warsaw
IN
|
Family ID: |
36609000 |
Appl. No.: |
12/825064 |
Filed: |
June 28, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
11236339 |
Sep 27, 2005 |
7744598 |
|
|
12825064 |
|
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Current U.S.
Class: |
606/86A |
Current CPC
Class: |
A61B 17/7032 20130101;
B25B 7/14 20130101; B25B 7/02 20130101; B25B 7/18 20130101; A61B
17/7034 20130101; A61B 17/2804 20130101; A61B 17/7088 20130101 |
Class at
Publication: |
606/86.A |
International
Class: |
A61B 17/56 20060101
A61B017/56 |
Claims
1-47. (canceled)
48. A method, comprising: providing an instrument for reducing an
elongated member to a channel in an orthopedic implant; connecting
an orthopedic implant having a channel for receiving an elongated
member to a bone; placing an elongated member proximate to said
implant; connecting a first portion of said instrument to said
elongated member and a second portion of said instrument to said
implant; pivoting said second portion of said instrument so that
said first portion urges said elongated member toward an alignment
with said channel of said implant.
49. The method of claim 48, further comprising: causing said first
portion and said second portion to move generally toward each other
so that said elongated member is forced toward said channel of said
implant.
50. The method of claim 49, further comprising: forcing said
elongated member into said channel; and locking said elongated
member with respect to said implant.
51. The method of claim 50, further comprising: disconnecting said
instrument from said implant and said elongated member after
performing said locking.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation in part of and claims
priority to U.S. patent application Ser. No. 11/043,318, filed Jan.
26, 2005.
BACKGROUND
[0002] In orthopedic surgical procedures, it is known to implant
devices to support bones or other tissue, to correct deformities,
to hold tissues in position for healing after injuries or other
surgery, and for other purposes relating to orthopedic health. For
example, where correction of a scoliotic or other abnormal
curvature or misalignment of the spine is desired, a sturdy rod,
plate, or other elongated connecting member can be placed along one
or more vertebral segments to support or hold the segments in a
corrected position. Bone screws, bone hooks or other fixation
implants are attached to vertebrae and connected to the connecting
member to secure the connecting member along the spinal column.
[0003] Commonly, the fixation implants and the connecting member(s)
are placed separately, that is, they are not connected together
prior to implantation in the body. For example, bone screws may be
implanted into vertebrae first, connectors may be placed on or
around the screws (if necessary), and then the connecting member
may be placed into the body. The connecting member may be contoured
prior to insertion to approximate the curvature desired, or it may
be contoured after placement adjacent the spine. In cases where a
connecting member and bone screws or other fixation elements are
separately placed, the connecting member and screws may be required
to be forced toward each other for connection. The process of
moving the connecting member and fixation elements toward each
other for connection is generally termed "reduction."
[0004] Reduction can be accomplished by hand, although the
environment and close quarters of a surgical site can make
reduction by hand quite difficult. While instruments have been
developed to provide a mechanical advantage in reducing or
positioning the connecting member relative to an anchor, there
remains a need for reducing instruments which are maneuverable
relative to the anchor and connecting member to facilitate
insertion and manipulation of the connecting member and anchor
through the incision or portal in which the reducing instrument is
positioned.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] FIG. 1 is a perspective view of an embodiment of an
instrument according to the present invention.
[0006] FIG. 2 is an exploded perspective view of the embodiment
shown in FIG. 1.
[0007] FIG. 3 is another view of the embodiment shown in FIG. 1 in
substantially a reverse perspective from that shown in FIG. 1, with
certain parts shown in exploded fashion.
[0008] FIG. 4 is a top plan view of an embodiment of an arm portion
of the embodiment shown in FIG. 1.
[0009] FIG. 5 is a side plan view of the embodiment shown in FIG.
4.
[0010] FIG. 6 is a partial cross-sectional view of the embodiment
shown in FIG. 4, taken along the line 6-6 in FIG. 5 and viewed in
the direction of the arrows.
[0011] FIG. 7 is a top plan view of an embodiment of an arm portion
of the embodiment shown in FIG. 1.
[0012] FIG. 8 is a cross-section view of the embodiment shown in
FIG. 7, taken along the line 8-8 in FIG. 7 and viewed in the
direction of the arrows.
[0013] FIG. 9 is a side plan view of the embodiment shown in FIG.
7.
[0014] FIG. 10 is a bottom plan view of the embodiment shown in
FIG. 7.
[0015] FIG. 11 is a side view of an embodiment of an instrument in
relation to an orthopedic rod and an orthopedic implant.
[0016] FIG. 12 is a side view of the embodiment shown in FIG. 11 in
relation to a reduced orthopedic rod.
[0017] FIG. 13A is a perspective view of arm portions of another
embodiment of an instrument according to the present invention in
relation to an orthopedic rod and an orthopedic implant.
[0018] FIG. 13B is a side view of the embodiment shown in FIG. 13A
in relation to an orthopedic rod and an orthopedic implant.
[0019] FIG. 14A is a perspective view of arm portions of another
embodiment of an instrument according to the present invention in
relation to an orthopedic rod and an orthopedic implant.
[0020] FIG. 14B is a side view of the embodiment shown in FIG. 14A
in relation to an orthopedic rod and an orthopedic implant.
[0021] FIG. 15A is a perspective view of arm portions of another
embodiment of an instrument according to the present invention in
relation to an orthopedic rod and an orthopedic implant.
[0022] FIG. 15B is a side view of the embodiment shown in FIG. 15A
in relation to an orthopedic rod and an orthopedic implant.
[0023] FIG. 16A is a perspective view of arm portions of another
embodiment of an instrument according to the present invention in
relation to an orthopedic rod and an orthopedic implant.
[0024] FIG. 16B is a side view of the embodiment shown in FIG. 16A
in relation to an orthopedic rod and an orthopedic implant.
[0025] FIG. 17 is a side view of another embodiment of an
instrument according to the present invention.
[0026] FIG. 18 is a perspective view of an arm portion of another
embodiment of an instrument according to the present invention.
[0027] FIG. 19 is side view of arm portions of another embodiment
of an instrument according to the present invention in relation to
an orthopedic rod and an orthopedic implant.
[0028] FIG. 20 is side view of arm portions of another embodiment
of an instrument according to the present invention in relation to
an orthopedic rod and an orthopedic implant.
DESCRIPTION OF THE ILLUSTRATED EMBODIMENT
[0029] For the purposes of promoting an understanding of the
principles of the invention, reference will now be made to the
embodiment illustrated in the drawings and specific language will
be used to describe the same. It will nevertheless be understood
that no limitation of the scope of the invention is thereby
intended. Any such alterations and further modifications in the
illustrated device, and any such further applications of the
principles of the invention as illustrated herein, are contemplated
as would normally occur to one skilled in the art to which the
invention relates.
[0030] Referring generally to the figures, there is shown a
reducing instrument 20 that is removably engageable to an implant
(e.g. a bone screw or other anchor) and operable to move a rod or
other elongated connecting member and the implant toward each
other. Reducing instrument 20 includes handle portions 22 and 24,
springs 26 and 28, and arm portions 30 and 32. Use of instrument 20
allows good visibility of the implant and remote or sideward
positioning of the reducing instrument in alignment with the
implant.
[0031] Handle portion 22 is generally elongated, having a generally
proximal end 40 and a generally distal end 42. Proximal end 40 may
be pivotally connected to a toothed bar 44. Toothed bar 44 may be
pivotally connected at 46 to a ratchet post 48, having a slot 49,
which is pivotally connected to proximal end 40 of handle portion
22. Handle portion 22 may also have a thickened portion 50 to
provide a guide for the surgeon's hand, to provide a more stable or
secure connection to bar 44 and/or ratchet post 48 if they are
present, or for other purposes. Handle portion 22 also includes
hole 52 through which handle portion 22 can be connected to handle
portion 24. Hole 52 is formed through a part-circular portion 53
that extends from an inside surface of handle portion 22. Portion
53 is thinner than handle portion 22 and is substantially centered
on handle portion 22. Hole 52 is generally between proximal end 40
and distal end 42; in the illustrated embodiment hole 52 is
relatively close to or adjacent distal end 42. A forked portion 54
is provided at distal end 42, for connecting to an arm portion, as
further described below. Forked portion 54 includes holes 55a and
55b, one of which (e.g. 55a) may be threaded.
[0032] Handle portion 24 is generally elongated, having a generally
proximal end 60 and a generally distal end 62. Proximal end 60 may
include a pawl 64 for engaging toothed bar 44. Further, a release
lever 66 having a handle 68 and a contact surface 70 may be
pivotally connected to proximal end 60. Pressing on handle 68
causes lever 66 to pivot so that contact surface 70 pushes against
bar 44 to disengage bar 44 from pawl 64, allowing handle portions
22 and 24 to be spaced apart. Handle portion 24 also includes a
groove 72 that makes distal end 62 generally divided or forked.
Holes 74a and 74b through which handle portion 24 can be connected
to handle portion 22 are provided generally between proximal end 60
and distal end 62, and in the illustrated embodiment adjacent
distal end 62. Holes 74a and 74b are formed through part-circular
portions 76a and 76b that extend from an inside surface of handle
portion 24. Forked distal end 62 also includes holes 78a and 78b
for connecting to an arm portion, as further described below. One
or both of holes 78a and 78b (e.g. 78a) may be threaded.
[0033] In the illustrated embodiment, two leaf springs 26 and 28
are provided to bias handle portions 22 and 24 apart. Spring 26 is
attached at or adjacent to an end 90 to handle portion 22
relatively close to proximal end 40, as by a set screw 91 or other
connector. Spring 28 is attached at or adjacent to an end 92 to
handle portion 24 relatively close to proximal end 60, as by a set
screw 91 or other connector. Springs 26 and 28 may interengage, for
example via a tongue-and-groove type of engagement. In that
configuration, spring 26 may have a tongue portion 94 at the end
opposite end 90, and spring 28 may have a groove 96 at the end
opposite end 92. When springs 26 and 28 are attached to handle
portions 22 and 24, tongue 94 extends into and/or through groove
96. In one particular embodiment, spring 26 may have a tab 98 at or
adjacent to end 90 that can be inserted in slot 49 of ratchet post
46. Tab 98 acts as a spring to apply a force on bar 44 to maintain
bar 44 in contact with pawl 64. It will be seen that only one leaf
spring, such as spring 26 (with or without tongue 94 or tab 98) may
be provided for biasing handle portions 22 and 24 apart, or one or
more coil or other springs may be provided, or other appropriate
structure for biasing handle portions 22 and 24 apart.
[0034] Arm portion 30 is an elongated piece having a proximal end
110 and a distal end 112. A relatively thin part-circular portion
114 is provided at or adjacent proximal end 110 with a hole 116 for
connecting to hole 54 of handle portion 22. Arm portion 30 also
includes a grooved or forked portion 118 generally between proximal
end 110 and distal end 112 and in the illustrated embodiment
adjacent proximal end 112. Holes 120a and 120b through which arm
portion 30 can be connected to arm portion 32 are provided in
forked portion 118. Holes 120a and 120b are formed through
part-circular portions 121a and 121b that extend from an inside
surface of arm portion 30. One or both of holes 120a and 120b (e.g.
120a) may be threaded.
[0035] Distal end 112 has a substantially U-shaped portion 122
having extension portions 124 and 126 and cross-pieces 128 and 130.
In the illustrated embodiment, extension portions 124 and 126 are
substantially parallel to each other, and are substantially
perpendicular to cross-pieces 128 and 130. Cross piece 128, in one
embodiment, is essentially a lateral extension of the main part of
arm portion 30, and may have an indentation 129 through which a
screwdriver or other tool can be extended to reach an implant, as
for example to apply a locking member such as a set screw to the
implant. Cross-piece 130 may include a tab 132 generally extending
toward cross-piece 128, which may be at least partially curved,
e.g. to provide a surface with a curvature approximating that of an
orthopedic rod. Cross-piece 130 may also include an indentation 131
similar to indentation 129 and for a similar purpose. Extension
portions 124 and 126 include substantially part-cylindrical hollows
134 and 136, respectively. Hollows 134 and 136 are linear, i.e. the
axes of the cylinders of which hollows 134 and 136 are a part are
collinear, and hollows 134 and 136 may be of a size and curvature
to accommodate an orthopedic rod, e.g. forming a substantially
semi-circular (180-degree) section. In a particular embodiment, arm
portion 30 has a longitudinal axis L. U-shaped portion 122 is
laterally offset from axis L, and may be offset in a direction
substantially perpendicular to axis L. U-shaped portion 122 may
also be angled with respect to axis L, in a particular embodiment
so that U-shaped portion 122 bends toward arm portion 32. Such an
angle .alpha. may be about 160 degrees in one embodiment.
[0036] Arm portion 32 is an elongated piece having a proximal end
140 and a distal end 142. A relatively thin part-circular portion
144 is provided at or adjacent proximal end 140 with a hole 145 for
connecting to holes 78a and 78b of handle portion 24. Arm portion
30 also includes another relatively thin part-circular portion 146
with a hole 148 generally between proximal end 140 and distal end
142 and extending from an inside surface of arm portion 32, and in
the illustrated embodiment adjacent proximal end 142. Portion 146
fits within forked portion 118 of arm portion 30 so that hole 148
communicates with holes 120a and 120b.
[0037] Distal end 142 has a substantially U-shaped portion 152
having extension portions 154 and 156 and cross-piece 158. In the
illustrated embodiment, extension portions 154 and 156 are
substantially parallel to each other, and are substantially
perpendicular to cross-piece 158. Cross piece 158, in one
embodiment, is essentially a lateral extension of the main part of
arm portion 32. Extension portions 154 and 156 include protrusions
160 and 162 that may be substantially cylindrical. Protrusions 160
and 162 may be substantially linear, i.e. the axes of protrusions
160 and 162 are collinear, and may be relatively thin or short.
Protrusions 160 and 162 are for connecting to indentations or
hollows in an implant, and therefore they may be configured to
accommodate the shape, depth and/or other features of such
indentations or hollows.
[0038] In a particular embodiment, arm portion 32 has a
longitudinal axis M. U-shaped portion 152 can be laterally offset
from axis M, and may be offset in a direction substantially
perpendicular to axis M. As with portion 122 of arm 30, U-shaped
portion 152 could also be angled with respect to axis M in another
plane.
[0039] As has been suggested above, instrument 20 is assembled
generally as follows. Handle portions 22 and 24 are connected by
inserting thin portion 53 of handle portion 22 into grooved portion
72 of handle portion 24 so that hole 52 of handle portion 22
communicates with holes 74a and 74b of handle portion 24. An axle,
for example a rivet, pin or set screw (e.g. set screws 170 in FIG.
3), can be inserted through holes 52, 74a and 74b and secured so
that handle portions 22 and 24 can pivot with respect to each other
around such an axle. In an embodiment in which at least one of
holes 52, 74a and 74b are at least partially threaded, a set screw
may be used as the axle, with the relative advantage that the
interacting threads tend to retain the set screw within the holes.
In other embodiments, a separate retaining piece, such as a ring to
fit into a groove of an axle, or an additional step to retain the
axle within the holes, such as swaging or peening part of the axle,
can be included.
[0040] It will be seen that connection of handle portions 22 and 24
should account for connections of associated parts that may be
present. For example, in embodiments in which handle portion 22
includes toothed bar 44 and handle portion 24 includes pawl 64,
connection of handle portions 22 and 24 should ensure that bar 44
and pawl 64 connect. In embodiments including lever 66, lever 66
should be proximate to or abut bar 44. As another example, in
embodiments in which handle portions 22 and/or 24 include springs,
connection of handle portions 22 and 24 should ensure that the one
or more springs are proximate to or abut each other or the opposing
handle portion so that biasing apart of the handle portions 22 and
24 occurs. In one particular embodiment, as noted above leaf
springs 26 and 28 should be arranged so that tongue 94 of spring 26
is at least partially within groove 96 of spring 28.
[0041] Arm portions 30 and 32 are connected to each other, and each
is connected to one of the handle portions 22 and 24, substantially
as described above. Thin portion 146 of arm portion 32 is inserted
into grooved portion 118 of arm portion 30 so that hole 148 of arm
portion 32 communicates with holes 120a and 120b of arm portion 30.
An axle as described above can be inserted through holes 148, 120a
and 120b and secured so that arm portions 22 and 24 can pivot with
respect to each other around such an axle. A set screw (e.g. set
screws 170 in FIG. 3) may be used as such an axle, particularly in
embodiments in which at least one of holes 148, 120a and 120b are
at least partially threaded. Arm portion 30 is connected to handle
portion 22 by inserting thin portion 114 of arm portion 30 into the
forked end 54 of handle portion 22, so that hole 116 of arm portion
30 communicates with holes 55a and 55b of handle portion 22. An
axle as described above can be inserted through holes 116, 55a and
55b and secured so that arm portion 30 and handle portion 22 can
pivot with respect to each other around such an axle. A set screw
(e.g. set screws 170 in FIG. 3) may be used as such an axle,
particularly in embodiments in which at least one of holes 116, 55a
and 55b are at least partially threaded. Arm portion 32 is
connected to handle portion 24 by inserting thin portion 144 of arm
portion 32 into the forked end of handle portion 24, so that hole
145 of arm portion 32 communicates with holes 78a and 78b of handle
portion 24. An axle as described above can be inserted through
holes 145, 78a and 78b and secured so that arm portion 32 and
handle portion 24 can pivot with respect to each other around such
an axle. A set screw (e.g. set screws 170 in FIG. 3) may be used as
such an axle, particularly in embodiments in which at least one of
holes 145, 78a and 78b are at least partially threaded.
[0042] It will be seen that the several portions of embodiments of
instrument 20 can be connected in a variety of orders. For example,
arm portions 30 and 32 can be connected to each other, then to
individual handle portions 22 and 24, with the final connection
being that between handle portions 22 and 24. As another example,
handle portions 22 and 24 can be connected together first, then to
arm portions 30 and 32, with arm portions 30 and 32 being either
separate or already connected. The instrument 20 can be assembled
as indicated above and in FIGS. 1-3, with distal portions 112 and
142 of arms 30 and 32 offset to the left when handle portion 22 is
substantially atop handle portion 24. That positioning occurs when
handle portion 22 is directly connected to arm 30 and handle
portion 24 is directly connected to arm 32. Instrument 20 can also
be assembled so that arm 30 is directly connected to handle portion
24, and arm 32 is directly connected to handle portion 22. In that
case, distal portions 112 and 142 of arms 30 and 32 are offset to
the left when handle portion 24 is substantially atop handle
portion 22, as in FIGS. 11-12.
[0043] In using the illustrated embodiment of instrument 20, it
will be seen that squeezing handle portions 22 and 24 together
causes rotation of handle portions 22 and 24 with respect to each
other, so that their respective distal ends 42 and 62 move apart.
As distal ends 42 and 62 move apart, the proximal parts of arm
portions 30 and 32 also move apart. By virtue of the pivoting
connection of arm portions 30 and 32, when the proximal parts of
arm portions 30 and 32 move apart, their respective distal portions
112 and 142 move together. Thus, by squeezing handle portions 22
and 24 together, the distal portions 112 and 142 are forced
together.
[0044] The operation of instrument 20 to engage an implant and rod
or other connecting member and seat the connecting member in the
implant anchor will now be described with respect to operation on a
spinal column. Alternative uses with respect to other bony
structures or other tissues can be made. As with other types of
orthopedic surgery, an incision is made and access is gained to the
surgical site. The approach to the surgical site can be an open
approach, i.e. a relatively long incision with retraction of
underlying tissue. The instrument disclosed herein can be used in
such an approach, or with other surgical techniques.
[0045] After access to the surgical site has been obtained, anchors
such as those including a receiver member 180 are inserted into
bone tissue. Such anchors may be pre-fitted with receiver member
180 or other receiver member embodiment, and such anchors typically
include a bone engaging portion 182 and a channel 183 for
accommodating part of rod R. Such a channel 183 may point
substantially to the side as shown in the figures, or may open to
the back of the anchor, or be otherwise oriented. Such receiver
members may also be placed on or over engaging portions after
engagement of the engaging portions into bone, and may be
multi-axial, pivotable or otherwise adjustable with respect to such
engaging portions. A connecting member, such as rod R, is inserted
into the surgical site, and placed adjacent one or more of the
anchors. If not already present, receiver members 180 may be
loosely placed on the connecting member prior to insertion of the
connecting member to the surgical site. The anchors and connecting
member are manipulated so that a part of the connecting member is
in or near the each of the anchors. Receiver member 180 can include
a pair of branches 184 which generally form channel 183
therebetween. Instrument 20 may be used with a variety of anchors
or implants, including those known previously in the art and those
disclosed in U.S. patent application Ser. Nos. 11/000,585 filed on
Nov. 30, 2004 and 11/000,846 filed Dec. 1, 2004 and, respectively
entitled SIDE-LOADING ADJUSTABLE BONE ANCHOR and SIDE-LOADING BONE
ANCHOR, which are incorporated herein by reference in their
entireties.
[0046] After engagement of the implant to a vertebra, rod R is
positioned adjacent the implant. It is contemplated that a number
of implants can be positioned and engaged along the spinal column,
and the rod engaged in a channel or other area of one of the
implants. Due to misalignment of vertebrae, misalignment of the
implants, or other conditions, the rod may not be easily or readily
positioned in one or more implants.
[0047] Once the rod is adjacent an implant into which the rod is to
be placed or seated, instrument 20 may be introduced to reduce or
force the rod into the implant. With handle portions 22 and 24 in
an unstressed state, i.e. biased away from each other or otherwise
spread apart, distal ends 112 and 142 of arm portions 30 and 32 are
also spread apart. Distal ends 112 and 142 are placed around the
combination of rod R and receiver member 180, so that distal end
112 is adjacent to or abutting a surface of rod R relatively
distant from receiver member 180, and distal end 142 is adjacent to
or abutting a surface of receiver member 180 relatively distant
from rod R. In the embodiment in which distal end 142 includes
protrusion(s) 162, such protrusion(s) 162 are inserted or
maneuvered into hollow(s) or aperture(s) in receiver member 180. In
an alternative embodiment in which receiver member 180 includes one
or more side protrusions rather than hollow(s), distal end 142 may
be provided with one or more hollows 162', e.g. in extensions 154
and/or 156, to accommodate such protrusions.
[0048] Where protrusion(s) 162 or hollow(s) 162' are provided and
are substantially rounded or cylindrical and fit with corresponding
parts of receiver member 180, as previously described, instrument
20 can pivot or rotate with respect to receiver member 180, as seen
in one example in FIGS. 11-12. In that example, a distal portion of
arm 32 changes angle with respect to the anchor or implant, as in
FIG. 11 that portion of arm 32 is at an oblique angle with respect
to engaging portion 182, and in FIG. 12 that portion of arm 32 is
substantially parallel to engaging portion 182. The axis of
rotation in that example substantially corresponds with
protrusion(s) 162 or hollow(s) 162', is different from the axes
around which arms 22, 24, 30 and 32 pivot, and is substantially
parallel to the axis of channel 183 of receiver member 180. Such
pivoting or rotation around protrusion(s) 162 or hollow(s) 162' may
force rod R generally toward the bone or substantially
perpendicular to a bone surface (downward as seen in FIG. 11)
and/or generally toward receiver member 180. In other words, such
pivoting may force rod R generally obliquely with respect to a
longitudinal axis of implant 180, or in a direction that has at
least a component parallel to a longitudinal axis of implant 180.
Such pivoting or rotation can occur in this embodiment as may be
necessary for rod reduction.
[0049] Handle portions 22 and 24 are then squeezed together, which
as discussed above forces distal ends 112 and 142 of arm portions
30 and 32 toward each other. Forcing together distal ends 112 and
142 causes rod R and receiver member 180 to move relative to each
other so that they become nearer to each other. In many cases, the
rod will undergo all or substantially all of such relative
movement, and the implant (which is anchored to a bone) will remain
relatively stationary. However, it will be appreciated that in some
uses the surgeon would prefer the bone and implant to undergo
movement toward the rod, for example in some cases of significant
vertebral misalignment, and thus instrument 20 can cause such
movement of the implant, perhaps with direct manipulation of the
bone by the surgeon.
[0050] Squeezing of handle portions 22 and 24 is continued until
distal ends 112 and 142 of arm portions 30 and 32 force rod R and
receiver member 180 together to the extent desired by the surgeon.
Toothed bar 44 and pawl 64 interact to maintain handle portions 22
and 24 (and thus arm portions 30 and 32) in a squeezed state, and
keeping them from being biased apart if the surgeon's grip should
loosen. In this way, instrument 20 can maintain pressure on a rod
and implant while the surgeon rests his or her hand or performs
another task. As rod R enters receiver member 180, distal end 112
of arm portion 30 approaches the implant (e.g. generally parallel
to a bone or bone surface to which the implant is connected), and
specifically branches 184 on either side of channel 183 or other
area that accommodates the rod. Distal end 112 of arm portion 30 is
configured to be able to force rod R into receiver member 180 to
the greatest degree desired, because cross pieces 128 and 130 are
spaced apart so as to interfere minimally or not at all with
branches 184 of receiver member 180. Thus, as distal end 112
approaches branches 184 of receiver member 180, branches 184 enter
the gaps between cross pieces 128 and 130, allowing distal end 112
to press the rod toward or to the back of the implant, if that is
desired. Through such squeezing of instrument 20 or pivoting of
instrument 20 with respect to receiver member 180, or a combination
of the two motions, rod R is reduced into channel 183 of receiver
member 180.
[0051] Once the rod is positioned as the surgeon desires in the
implant, the rod is locked into the implant using structure (e.g.
set screw, cap, clamp) provided with the implant, as for example by
inserting the structure and an appropriate tool through
indentations 129 and 131 to the implant. Instrument 20 may be
removed from contact with the rod and the implant after such
locking, or before if the rod will remain at least approximately in
the position desired by the surgeon. When it is desired to remove
or loosen the contact of instrument 20 with the rod and/or the
implant, the surgeon may press lever 68, which pivots to push
toothed bar 44 away from pawl 64. Springs 26 and 28 then act to
push handle portions 22 and 24 apart, per their normal bias, and
distal portions 112 and 142 of arm portions 30 and 32 come away
from the rod and the implant. The surgeon may then move to
reduction of the rod into another implant, or may remove instrument
20 from the surgical site to perform other tasks or conclude the
surgical procedure.
[0052] FIGS. 13A-13B illustrate a portion of a reducing instrument
220 according to another embodiment. In that embodiment, instrument
220 includes arm portions 30 and 232. Instrument 220 may further
include handle portions and springs (not shown for clarity),
similar in structure and function to handle portions 22 and 24 and
springs 26 and 28, and connected as described in with respect to
previous embodiments, as are other embodiments described below.
Additionally, instrument 220 may include a toothed bar and pawl
assembly, as previously described. Arm portion 232 is an elongated
piece having a proximal end 240 and a distal end 242. It should be
appreciated that arm portion 232 connects with a corresponding
handle portion in a substantially similar manner as arm portion 32
connects with handle portion 24.
[0053] Distal end 242 has an extension portion 254. Extension
portion 254 may generally increase in width from a proximal point
254a to a distal point 254b. In the illustrated embodiment,
extension portion 254 includes one section of increasing width;
however, it should be appreciated that extension portion 254 can be
configured differently. Extension portion 254 includes an
approximately 90 degree bend in the illustrated embodiment at bend
point 260 between a proximal portion 262 and a distal portion 264.
The extension portion 254 may bend in a direction toward an anchor,
with distal portion 264 being substantially perpendicular to
proximal portion 262. Distal portion 264 includes a section 266,
which is generally cylindrical in one particular embodiment, at
distal point 254b. Section 266 can be configured to contact an
anchor, such as anchor 270. It should be appreciated that
instrument 220 may be used with a variety of anchors or implants.
Additionally, section 266 can be larger or smaller to fittingly
contact various sized channels in various anchors or implants.
[0054] In the illustrated embodiment, anchor 270 includes a
receiver portion 280 and an engaging portion 282. In certain
embodiments, receiver portion 280 includes a first channel 283 and
a second channel 284. Part of a rod R can be accommodated in one of
channels 283 or 284, depending on which channel is closer to or
more exposed to rod R. In the illustrated embodiment, rod R is to
be loaded into channel 283, and therefore section 266 of instrument
220 can be inserted into channel 284 in order to reduce or force
rod R toward or into channel 283. Receiver portion 280 in the
illustrated embodiment is integral with respect to engaging portion
282. A threaded cap (not shown) can thread onto receiver portion
280 to hold rod(s) or other elongated members with respect to
receiver member 280.
[0055] FIGS. 14A-14B illustrate a portion of instrument 220 used in
conjunction with an anchor 370 including a receiver member 380 and
an engaging portion 382. Anchor 370 is substantially similar in
structure and function to the anchors previously described herein
(e.g. those shown in FIGS. 11-12). Receiver member 380 includes a
first channel 383 for accommodating part of rod R. Such a channel
383 may point substantially to the side as shown in the figures, or
may open to the back of a similar anchor, or be otherwise oriented.
In certain embodiments, receiver member 380 also includes a second
channel 384 for accommodating part of segment 266.
[0056] FIG. 15A-15B illustrate a portion of another embodiment of a
reducing instrument 420. Instrument 420 includes arm portions 30
and 432. Instrument 420 may further include handle portions and
springs (not shown for clarity), similar in structure and function
to handle portions 22 and 24 and springs 26 and 28. Additionally,
instrument 420 may include a toothed bar and pawl assembly, as
previously described. Arm portion 432 is an elongated piece having
a proximal portion 440 and a distal end 442 in the illustrated
embodiment. It should be appreciated that arm portion 432 connects
with a corresponding handle portion in a substantially similar
manner as arm portion 32 connects with handle portion 24.
[0057] Distal end 442 includes an extension portion 454. Extension
portion 454 may generally increase in width from a proximal point
454a to a distal point 454b. In the illustrated embodiment,
extension portion 454 includes one section of increasing width;
however, it should be appreciated that extension portion 454 can be
configured differently. Extension portion 454 includes extension
pieces 455 and 456, and a cross piece 458. In the illustrated
embodiment, extension pieces 455 and 456 are substantially parallel
to each other and to the body of arm 432, and are substantially
perpendicular to cross-piece 458. The extension pieces are
connected at distal point 454b with a section 466 that is
substantially cylindrical in the illustrated embodiment. Section
466 is configured to contact an anchor, such as anchor 270. Section
466 can be larger or smaller to fittingly contact various sized
channels in various anchors or implants.
[0058] In the embodiment illustrated in FIGS. 15A and 15B,
instrument 420 is used in conjunction with an anchor 270 including
receiver member 280 and engaging portion 282. Extension pieces 455.
456, cross-piece 458, and section 466 all generally define a gap
468. Gap 468 is sufficiently sized and configured to admit one of
the anchor branches defining second channel 284 of anchor 270.
[0059] FIGS. 16A-16B illustrate a portion of instrument 420 used in
conjunction with an anchor 370 including receiver member 380 and
engaging portion 382. Receiver member 380 also includes second
channel 384 for accommodating part of cylindrical segment 466.
[0060] FIG. 17 illustrates another embodiment of a reducing
instrument 520. Instrument 520 includes handle portions 22 and 24,
springs 26 and 28, and arm portions 530 and 532. Additionally,
instrument 520 may include a toothed bar 44 and a pawl 64, as
previously described. It should be appreciated that arm portions
530 and 532 connect with handle portions 22 and 24, respectively,
in a substantially similar manner as arm portions 30 and 32 connect
with the handle portions. Arm portions 530 and 532 have proximal
ends 530a and 532a, and distal ends 530b and 532b, respectively.
Additionally, arm portions 530 and 532 each include sections of
curvature 540 and 542, respectively, positioned between the
proximal and distal ends. In certain embodiments, the sections of
curvature prevent interference with various tissues and/or other
structures or materials within or adjacent to the patient or the
surgical site. Distal ends 530b and 532b can be sized and
configured in a manner as previously described to contact and
engage an anchor and rod or other connecting member and seat the
connecting member in the anchor.
[0061] In some embodiments, sections 540, 542 are generally
positioned in the same plane as the handle portions and arm
portions. In other words, sections of curvature 540, 542 generally
open in a direction from one arm portion to the other arm portion.
In the illustrated embodiment, section 540 opens towards section
542, and concave portions of sections 540 and 542 face in generally
the same direction (e.g. the left as shown in FIG. 17). However, it
should be appreciated that sections 540, 542 can be arranged,
oriented or configured differently.
[0062] FIG. 18 illustrates a portion of an arm 630 of a reducing
instrument in another embodiment. Arm 630 includes a proximal end
(not shown) that may be similar or identical to ends of arms
described above, and a distal end 612. Distal end 612 includes
extension portions 624 and 626 (similar to extensions 134 and 136
and those shown in FIGS. 13A, 14A, 15A and 16A), which may include
part-cylindrical hollows 634 and 636, respectively. Hollows 634 and
636 are linear, e.g. the axes of the cylinders of which hollows
634, 636 are a part are collinear, and hollows 634, 636 may be of a
size and curvature to accommodate an orthopedic rod R. In the
illustrated embodiment, hollows 634, 636 each form a substantially
quarter-circular (90-degree) section 640, with an adjacent straight
segment 642. The absence of a lower lip on one or both hollows 634,
636, as in the illustrated embodiment, can encourage accommodation
of an angled rod, e.g. one not perpendicular to extension portions
624 and 626 when their instrument is inserted to the surgical site,
or other elongated members of various configurations.
[0063] FIG. 19 illustrates a portion of a reducing instrument 720
in another embodiment. Instrument 720 includes arm portions 30 and
732. Instrument 720 may further include handle portions and springs
(not shown for clarity), similar in structure and function to
handle portions 22 and 24 and springs 26 and 28. Additionally,
instrument 720 may include a toothed bar and pawl assembly, as
previously described. Arm portion 732 is an elongated piece having
a proximal end 740 and a distal end 742. It should be appreciated
that arm portion 732 connects with a corresponding handle portion
in a substantially similar mariner as arm portion 32 connects with
handle portion 24. A protrusion 766 is disposed on arm portion 732
at distal end 742. In the illustrated embodiment, protrusion 766 is
spherical; however, it should be appreciated that protrusion 766
can be configured differently. Protrusion 766 is configured to
contact an anchor 770, similar in configuration to anchor 370. In
certain embodiments, anchor 770 can include a recess configured to
receive a portion of protrusion 766. In one embodiment, protrusion
766 extends the width of arm portion 732. In another embodiment,
arm portion 732 may include two extension portions, and a
protrusion such as protrusion 766, disposed on each distal end of
the extension portions.
[0064] FIG. 20 illustrates a portion of a reducing instrument 820
according to another embodiment. Instrument 820 includes arm
portions 30 and 832. Instrument 820 may further include handle
portions and springs (not shown for clarity), similar in structure
and function to handle portions 22 and 24 and springs 26 and 28.
Additionally, instrument 820 may include a toothed bar and pawl
assembly, as previously described. Arm portion 832 is an elongated
piece having a proximal end 840 and a distal end 842. It should be
appreciated that arm portion 832 connects with a corresponding
handle portion in a substantially similar manner as arm portion 32
connects with handle portion 24. In the illustrated embodiment, a
protrusion 866 is disposed on an anchor 870, similar in
configuration to anchor 370. Protrusion 866 is shown to be
spherical in one embodiment; however, it should be appreciated that
protrusion 866 can be configured differently. Protrusion 866 is
positioned on the receiver portion of anchor 870, opposite a
channel for receiving a portion of an orthopedic rod R or other
elongated member. In certain embodiments, the arm portion includes
a recess 890 at distal end 842 configured to receive a portion of
protrusion 866.
[0065] In an alternative embodiment, arm portion 832 of reducing
instrument 820 could include a recess configured to receive a
portion of a receiver member of an anchor (e.g. anchor 370). In
such an embodiment, the recess in the arm portion would fittingly
contact a portion of a receiver member of an anchor, the portion
being opposite a channel configured to receive an orthopedic rod.
In such an embodiment, protrusion 866 may be absent and the recess
in the arm portion partially surrounds the receiver member of the
anchor. The recess may include a generally spherical configuration
or another such appropriate configuration. In such an embodiment,
the recess in the arm portion, and the portion of the receiver
member contacting the recess in the arm portion, would generally
include similar degrees of curvature so that the arm portion would
fittingly contact the anchor.
[0066] The assembly and operation of reducing instruments 220, 420,
520, 720, and 820 is substantially similar to the assembly and
operation of reducing instrument 120 described above. As an
example, the arm portions of the reducing instruments 220, 420,
520, 720, and 820 connect to each other in a substantially similar
manner as arm portions 30 and 32 connect together.
[0067] Regarding the operation of embodiments of reducing
instruments 220, 420, 520, 720, and 820, after access to the
surgical site has been obtained, anchors such as those including
receiver members 280 or 380 are inserted into bone tissue. Such
receiver members may also be placed on or over engaging portions
after engagement of the engaging portions into bone, and may be
multi-axial, pivotable or otherwise adjustable with respect to such
engaging portions. A connecting member, such as rod R, is inserted
into the surgical site, and placed adjacent one or more of the
anchors. The anchors and connecting member are manipulated so that
a part of the connecting member is in or near the each of the
anchors, and such manipulation can be accomplished using
embodiments of reducing instruments such as those described above.
The instruments may be used with a variety of anchors or implants,
including those known previously in the art and those described
above.
[0068] During operation, the embodiments of reducing instruments
described above operate generally similarly to each other, and
therefore for simplicity operation of the embodiment of instrument
220 will be described. These descriptions of operation and those
given above apply to other embodiments as well. Instrument 220
engages an implant and rod or other connecting member to insert or
seat the connecting member in the implant. Such operation can
include reducing or forcing the rod into the implant once the rod
is positioned adjacent the implant into which the rod is to be
placed or seated. The distal ends of the arm portions are placed
around the rod and the receiver member of the anchor. The handle
portions are squeezed together, forcing the distal ends of the arm
portions towards each other, and causing the rod and the receiver
member to become nearer to each other and eventually for the rod to
be inserted into the receiver member. The toothed bar and pawl
assemblies, if present, interact to maintain the handle portions
squeezed together. Once the rod is positioned, the rod can be
locked into the implant anchor. A lever, if provided, can be
pressed to disengage the toothed bar from the pawl, and the handle
portions can be moved apart (e.g. by springs, if present) to enable
removal of instrument 220 from the surgical site. Thus, through
squeezing of an embodiment of the instrument or pivoting of an
embodiment of the instrument with respect to an anchor or a
receiver member or portion of an anchor, or a combination of the
two motions, a rod may be reduced into a channel of the anchor or
its receiver member.
[0069] As described above, the anchors and connecting member may be
positioned in or along one or more parts of the spine, including
the cervical, thoracic, lumbar and/or sacral portions. Although the
use of embodiments of instruments is described in the above
context, such embodiments and others could be used with a variety
of screws, hooks or other fixation implants, or in connection with
orthopedic implants in parts of the body other than the spine.
[0070] The above embodiments and others may be made of stainless
steel, certain hard plastics, or other materials that are
compatible with surgical procedures and the implants and rods with
which they are used. Features particularly described above in
connection with one embodiment may be used or incorporated into
other embodiments. For example, arm configurations or distal end
configurations shown in one figure could be used in connection with
apparatus shown in other figures.
[0071] While the invention has been illustrated and described in
detail in the drawings and foregoing description, the same is to be
considered as illustrative and not restrictive in character, it
being understood that all changes and modifications that come
within the spirit of the invention are desired to be protected.
* * * * *