U.S. patent application number 14/461002 was filed with the patent office on 2016-02-18 for surgical plan options for robotic machining.
The applicant listed for this patent is Stryker Corporation. Invention is credited to Stuart L. Axelson, JR., John R. Fossez, Emily Hampp, Lou Keppler, Sathiya Prabaharan.
Application Number | 20160045268 14/461002 |
Document ID | / |
Family ID | 55301251 |
Filed Date | 2016-02-18 |
United States Patent
Application |
20160045268 |
Kind Code |
A1 |
Keppler; Lou ; et
al. |
February 18, 2016 |
SURGICAL PLAN OPTIONS FOR ROBOTIC MACHINING
Abstract
A method of performing surgery on a bone includes providing a
robotically controlled bone preparation system and creating at
least one hole in the bone with the robotically controlled bone
preparation system prior to machining the bone. The bone hole
aligns with a hole or a post in a guide for a manual cutting tool.
If the robot fails during surgery, or if the surgeon does not wish
to complete the procedure with the robot, the guide is attached to
the bone after aligning the guide hole with the bone hole. The
surgery is completed manually after the guide is attached to the
bone, and the robot is not used after the guide is attached to the
bone.
Inventors: |
Keppler; Lou; (Lakewood,
OH) ; Prabaharan; Sathiya; (Parsippany, NJ) ;
Hampp; Emily; (Far Hills, NJ) ; Axelson, JR.; Stuart
L.; (Succasunna, NJ) ; Fossez; John R.;
(Frisco, TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Stryker Corporation |
Kalamazoo |
MI |
US |
|
|
Family ID: |
55301251 |
Appl. No.: |
14/461002 |
Filed: |
August 15, 2014 |
Current U.S.
Class: |
606/79 |
Current CPC
Class: |
A61B 17/157 20130101;
A61B 17/32 20130101; A61B 34/30 20160201; A61B 17/1764 20130101;
A61B 90/11 20160201; A61B 17/155 20130101 |
International
Class: |
A61B 19/00 20060101
A61B019/00; A61B 17/17 20060101 A61B017/17; A61B 17/32 20060101
A61B017/32; A61B 17/16 20060101 A61B017/16 |
Claims
1. A method of performing surgery on a bone comprising: providing a
robotically controlled bone preparation system capable of preparing
the bone according to a preoperative surgical plan pursuant to
which an implant is to be coupled to the prepared bone in a
preoperatively planned position and orientation; and machining at
least one contingency preparation in the bone with the robotically
controlled bone preparation system, wherein the position of the at
least one contingency preparation in the bone corresponds to a
portion of a guide for guiding a manual cutting tool such that the
guide could be used to prepare the bone according to the
preoperative surgical plan; and completing the surgery according to
the preoperative plan by either using the robotically controlled
bone preparation system or manually using the guide in association
with the contingency preparation.
2. The method of claim 1, wherein the contingency preparation is a
hole.
3. The method of claim 2, further comprising the step of removing
at least one anatomical landmark of the bone after the step of
creating at least one contingency hole in the bone, wherein the at
least one anatomical landmark would have been used in determining a
position and orientation of the guide with respect to the bone.
4. The method of claim 3, further comprising the step of attaching
the guide to the bone after aligning the portion of the guide with
the at least one contingency hole.
5. The method of claim 4, wherein the portion of the guide is
either a guide hole or a guide post.
6. The method of claim 4, wherein the guide includes a tracker for
use with a surgical navigation system.
7. The method of claim 4, further comprising the step of completing
the surgery manually after the step of attaching the guide to the
bone, wherein the robotically controlled bone preparation system is
not used after the guide is attached to the bone.
8. The method of claim 7, wherein the step of completing the
surgery manually includes manually debulking the femur and tibia
facilitated by a surgical navigation system.
9. The method of claim 2, wherein the step of creating at least one
contingency hole in the bone comprises creating at least one
contingency hole in a femur and at least one contingency hole in a
tibia.
10. A method of performing surgery on a bone comprising: providing
a robotically controlled bone preparation system to prepare the
bone according to a preoperative surgical plan; operating the
robotically controlled bone preparation system to machine the bone
to have features corresponding to features of a manual cutting
guide; and coupling the manual cutting guide to the bone.
11. The method of claim 9, further comprising the step of operating
the robotically controlled bone preparation system to further
machine the bone such that at least one anatomical landmark is
modified prior to coupling the manual cutting guide to the
bone.
12. The method of claim 10, wherein the step of coupling the manual
cutting guide to the bone occurs after the robotically controlled
bone preparation system has at least partially failed to machine
the bone according to the preoperative surgical plan.
13. The method of claim 10, wherein the step of operating the
robotically controlled bone preparation system to machine the bone
includes creating at least one hole in the bone.
14. The method of claim 13, wherein the at least one hole in the
bone corresponds to at least one hole or post in the manual cutting
guide.
15. The method of claim 14, further comprising the step of
attaching the manual cutting guide to the bone after aligning the
at least one guide hole or post with the at least one hole in the
bone.
16. The method of claim 15, wherein the guide includes a tracker
for use with a surgical navigation system.
17. The method of claim 15, further comprising the step of
completing the surgery manually after the step of attaching the
guide to the bone, wherein the robotically controlled bone
preparation system is not used after the guide is attached to the
bone.
18. The method of claim 17, wherein the step of completing the
surgery manually includes manually debulking the femur and tibia
facilitated by a surgical navigation system.
19. A method of performing surgery on a bone comprising: providing
a robotically controlled bone preparation system to make bone
resections; operating the robotically controlled bone preparation
system to machine the bone to have features corresponding to
features of a guide for guiding a manual cutting tool; coupling the
guide to the bone; and resecting the bone with the manual cutting
tool guided by the guide.
20. The method of claim 19, wherein the step of operating the
robotically controlled bone preparation system to machine the bone
includes creating at least one hole in the bone.
21. The method of claim 20, wherein the at least one hole in the
bone corresponds to at least one hole or post in the guide.
22. The method of claim 21, further comprising the step of
attaching the guide to the bone after aligning the at least one
guide hole or post with the at least one hole in the bone.
23. The method of claim 22, further comprising the step of
completing the surgery manually after the step of attaching the
guide to the bone, wherein the robotically controlled bone
preparation system is not used in the surgery after the guide is
attached to the bone.
24. The method of claim 23, wherein the guide includes a tracker
for use with a surgical navigation system.
25. The method of claim 23, wherein the completed surgery is a
total knee arthroplasty.
26. The method of claim 25, wherein the step of creating at least
one hole in the bone comprises creating at least two holes in a
femur and at least two holes in a tibia.
27. The method of claim 26, wherein the step of attaching the guide
to the bone comprises attaching a femoral resection guide to the
femur.
28. The method of claim 26, wherein the step of attaching the guide
to the bone comprises attaching a tibial resection guide to the
tibia.
29. The method of claim 23, wherein the completed surgery is a
partial knee arthroplasty.
30. The method of claim 29, wherein the step of creating at least
one hole in the bone comprises creating at least two holes in a
femur and at least two holes in a tibia.
31. The method of claim 30, wherein the step of attaching the guide
to the bone comprises attaching a femoral resection guide to the
femur.
32. The method of claim 31, wherein the step of completing the
surgery manually includes manually resecting the femur facilitated
by a surgical navigation system.
33. The method of claim 28, wherein the step of attaching the guide
to the bone comprises attaching a tibial resection guide to the
tibia.
34. The method of claim 33, wherein the step of completing the
surgery manually includes manually resecting the tibia facilitated
by a surgical navigation system.
35. A method of performing surgery on a bone comprising: providing
a robotically controlled bone preparation system to make bone
resections; operating the robotically controlled bone preparation
system to machine the bone to have features corresponding to
features of a surgical instrument, wherein the robotic machining
has at least one of increased accuracy, reproducibility, and speed
compared to manual resections; and manually completing the surgery
on the bone without further use of the robotically controlled bone
preparation system, including the step of manually coupling the
surgical instrument to the bone.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to surgical options for
navigated and/or robotic bone machining and in particular relates
to having the option of completing joint arthroplasty procedures
with conventional instruments following the use of navigated and/or
robot based applications.
BACKGROUND OF THE INVENTION
[0002] In a traditional joint arthroplasty procedure, such as a
total knee arthroplasty ("TKA") surgery, diseased bone and/or
cartilage of a patient is generally removed and replaced with a
prosthetic implant. A surgeon may resect the bone using a hand-held
oscillating saw blade which results in a series of planar bone
surfaces. Additionally, the surgeon may use a drill, broach or tamp
instrument to make cylindrical holes into the bone in order to
accommodate fixation features on the implant. The planar bone
surfaces and cylindrical bone holes, for example, are generally
oriented to interface with flat surfaces and pegs or keels of a
prosthetic implant.
[0003] In such arthroplasty surgeries, the cartilage and/or bone of
a patient may be prepared by a surgeon using conventional manual
instrumentation. The instrumentation used may include, for example,
planar resection guides, oscillating saws, drills, chisels, punches
and reamers.
[0004] Robotic surgery may also be used in arthroplasty procedures,
as well as in many different medical applications. The use of
robotically controlled bone preparation systems allows for
preoperatively planned bone preparation to be carried out with
increased accuracy and repeatability. Further, when a milling or
burring cutting tool is used, there may be opportunity to evolve to
non-planar and non-cylindrical bone resections. Therefore, robotic
preparation may be used with prosthetic implants having bone
contacting geometries designed to optimize contacting surfaces
and/or clearances with bone. Such implants generally have an
increased ability to improve the load transfer through the
implant-bone interface while considering patient kinematics and
articular surface geometries.
[0005] Cartilage and/or bone may be prepared with the assistance of
a robot in arthroplasty procedures. Robot assisted arthroplasty may
include the use of the following, for example: implant specific
software, milling/burring or other rotational cutting instruments
and various levels of surgeon interface. For example, in one robot
mode, the robot may perform the cartilage/bone preparation with the
surgeon observing. In another robot mode, the surgeon may actually
guide a cutting tool, such as a rotational cutting tool or saw,
such as an oscillating or reciprocating saw, within a predetermined
boundary or within a constrained boundary where manual milling is
contained. In all modes, the surgeon must be able to stop the
robotic preparation if required. Robotic technology may include
that described in U.S. Pat. Nos. 6,676,669, 7,892,243, 6,702,805,
6,723,106, and 7,950,306 as well as U.S. Patent Application Nos.
2010/0268249, 2010/0268250, 2010/0275718, and 2003/0005786, the
disclosures of all of which are hereby incorporated by reference in
their entireties. Using robotic preparation may enable the
development of new implant designs having substantially non-planar
bone contacting geometries and improved fixation features, but
potential drawbacks may exist. For example, current robotic
surgical techniques may leave the surgeon without a contingency
plan if the robotic device fails mid-surgery. In such a case, the
surgeon may need to resort to using standard instruments to
complete the particular procedure. However, the transition to
standard instrumentation mid-procedure may be difficult,
particularly if bony landmarks have already been resected. It would
thus be desirable to have apparatus and methods to facilitate a
surgeon transitioning from a robotic to manual procedure during a
surgical procedure.
BRIEF SUMMARY OF THE INVENTION
[0006] In one exemplary surgical procedure, a robot-specific plan
is created for a particular patient. This plan may involve, for
example, precise non-planar cuts that would be difficult or even
impossible for a surgeon to make manually. While such a robotic
plan may provide for potential advantages over traditional manual
plans using conventional tools and planar cuts, there is always a
possibility that the robot may fail at any point during surgery.
For example, the guidance system (also known as a navigation or
"NAV" system) may stop working, or the robot itself may stop
working properly.
[0007] If the robot fails mid-surgery, for example, the surgeon may
need to use conventional instrumentation to complete the particular
procedure. However, this may be difficult as bone has already been
removed by the robot, generally with non-planar cuts. While
conventional instrumentation is generally used in conjunction with
planar cuts and with pre-drilled reference points, making the use
of conventional instruments to finish the surgery with non-planar
cuts at this point would be difficult. Even if the surgeon is able
to complete the procedure after the robot has failed, the results
are likely to be different than the preoperatively planned or
originally intended results with the robot performing the
procedure. With the foregoing in mind, the present invention
includes contingency plans available for use in robotic surgical
procedures to facilitate the surgeon quickly and easily completing
the surgery according to the original plan if the robot fails
mid-surgery. It should also be noted, as described in detail below,
that the contingency plans may also be used when the surgeon
intends to complete the procedure manually after a robot has
performed some initial machining.
[0008] In one embodiment of the present invention, a method of
performing surgery on a bone includes providing a robotically
controlled bone preparation system to prepare the bone according to
a preoperative surgical plan such that an implant can be coupled to
the prepared bone in a preoperatively planned position and
orientation. The preoperative surgical plan includes determining
the location and orientation of one or more guide holes in the bone
in order to complete the procedure with conventional
instrumentation. According to this method, once the preoperative
plan is created, navigated and/or robot machining is used to create
the one or more guide holes in the bone. One or more conventional
instruments such as an alignment rod, for example, is then located
and oriented with respect to the bone using the one or more guide
holes. In this embodiment, the conventional instruments are not
being used based on a contingency plan, but are rather being used
according to the preoperative plan.
[0009] In one embodiment of the present invention, a method of
performing surgery on a bone includes providing a robotically
controlled bone preparation system and creating at least one hole
in the bone with the robotically controlled bone preparation system
prior to machining the bone, wherein the at least one bone hole in
the bone aligns with at least one hole or post in a guide for a
manual cutting tool. The method may further include the step of
initiating a debulking phase of the surgery with the robotically
controlled bone preparation system after the step of creating at
least one hole in the bone. The method may still further include
the step of attaching the guide to the bone after aligning the at
least one guide hole or post with the at least one bone hole. Still
further, the method may include the step of completing the surgery
manually after the step of attaching the guide to the bone, wherein
the robotically controlled bone preparation system is not used
after the guide is attached to the bone. The guide may include a
tracker for use with a surgical navigation system.
[0010] In one embodiment, the completed surgery may be a total knee
arthroplasty. The step of creating at least one hole in the bone
may include creating at least two holes in a femur and at least two
holes in a tibia. The step of attaching the guide to the bone may
include attaching a femoral resection guide to the femur and/or
attaching a tibial resection guide to the tibia.
[0011] In another embodiment, the completed surgical procedure may
be a partial knee arthroplasty. The step of creating at least one
hole in the bone may include creating at least two holes in a femur
and at least two holes in a tibia. The step of attaching the guide
to the bone may include attaching a femoral resection guide to the
femur and/or attaching a tibial resection guide to the tibia. The
step of completing the surgery manually may include manually
debulking the femur facilitated by a surgical navigation system
and/or manually debulking the tibia facilitated by a surgical
navigation system.
[0012] In a further embodiment, the method includes the step of
manually completing the surgery without further use of the
robotically controlled bone preparation system after the
robotically controlled bone preparation system creates the at least
one bone hole.
[0013] In yet another embodiment of the invention, a method of
performing surgery on a bone includes providing a robotically
controlled bone preparation system to prepare the bone according to
a preoperative surgical plan such that an implant can be coupled to
the prepared bone in a preoperatively planned position and
orientation. The method may also include creating at least one
contingency hole in the bone with the robotically controlled bone
preparation system prior to preparing the bone according to the
preoperative surgical plan, wherein the position of the at least
one contingency hole in the bone corresponds to at least one hole
or post in a guide for guiding a manual cutting tool that could be
used to prepare the bone according to the preoperative surgical
plan. The method may further include removing at least one
anatomical landmark of the bone after the step of creating at least
one contingency hole in the bone, wherein the at least one
anatomical landmark would have been used in determining a position
and orientation of the guide with respect to the bone. The method
may also include attaching the guide to the bone after aligning the
at least one guide hole or post with the at least one contingency
hole. The guide may include a tracker for use with a surgical
navigation system. The surgery may be completed manually after the
step of attaching the guide to the bone, wherein the robotically
controlled bone preparation system is not used after the guide is
attached to the bone. The method may also include manually
debulking the femur and tibia facilitated by a surgical navigation
system. The step of creating at least one contingency hole in the
bone may include creating at least one contingency hole in a femur
and at least one contingency hole in a tibia.
[0014] In still another embodiment of the invention a method of
performing surgery on a bone includes providing a robotically
controlled bone preparation system to prepare the bone according to
a preoperative surgical plan. The method may also include operating
the robotically controlled bone preparation system to machine the
bone to have features corresponding to features of a manual cutting
guide, and coupling the manual cutting guide to the bone. The
method may also include operating the robotically controlled bone
preparation system to further machine the bone such that at least
one anatomical landmark is modified prior to coupling the manual
cutting guide to the bone. The step of coupling the manual cutting
guide to the bone may occur after the robotically controlled bone
preparation system has at least partially failed to machine the
bone according to the preoperative surgical plan. The step of
operating the robotically controlled bone preparation system to
machine the bone may include creating at least one hole in the
bone. The at least one hole in the bone may correspond to at least
one hole or post in the manual cutting guide. The method may also
include attaching the manual cutting guide to the bone after
aligning the at least one guide hole or post with the at least one
hole in the bone. The guide may include a tracker for use with a
surgical navigation system. The method may also include the step of
completing the surgery manually after the step of attaching the
guide to the bone, wherein the robotically controlled bone
preparation system is not used after the guide is attached to the
bone. The step of completing the surgery manually may include
manually debulking the femur and tibia facilitated by a surgical
navigation system.
[0015] In still a further embodiment of the invention, a method of
performing surgery on a bone includes providing a robotically
controlled bone preparation system to make bone resections,
operating the robotically controlled bone preparation system to
machine the bone to have features corresponding to features of a
guide for guiding a manual cutting tool, coupling the guide to the
bone, and resecting the bone with the manual cutting tool guided by
the guide. The step of operating the robotically controlled bone
preparation system to machine the bone may include creating at
least one hole in the bone. The at least one hole in the bone may
correspond to at least one hole or post in the guide. The method
may also include attaching the guide to the bone after aligning the
at least one guide hole or post with the at least one hole in the
bone. The surgery may be completed manually after the step of
attaching the guide to the bone, wherein the robotically controlled
bone preparation system is not used in the surgery after the guide
is attached to the bone. The guide may include a tracker for use
with a surgical navigation system. The completed surgery may be a
total knee arthroplasty. The step of creating at least one hole in
the bone may include creating at least two holes in a femur and at
least two holes in a tibia. The step of attaching the guide to the
bone may include attaching a femoral resection guide to the femur
and/or a tibial resection guide to the tibia. The completed surgery
may also be a partial knee arthroplasty. The step of creating at
least one hole in the bone may include creating at least two holes
in a femur and at least two holes in a tibia. The step of
completing the surgery manually may include manually resecting the
femur and/or manually resecting the tibia facilitated by a surgical
navigation system.
[0016] In yet another embodiment of the invention, a method of
performing surgery on a bone includes providing a robotically
controlled bone preparation system to make bone resections. The
method may also include operating the robotically controlled bone
preparation system to machine the bone to have features
corresponding to features of a surgical instrument, wherein the
robotic machining has at least one of increased accuracy,
reproducibility, and speed compared to manual resections. The
method may further include manually completing the surgery on the
bone without further use of the robotically controlled bone
preparation system, including the step of manually coupling the
surgical instrument to the bone.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 is a partial perspective view of a robot preparing
contingency or bailout holes in a femur and tibia.
[0018] FIG. 2A is a flow chart representing steps of a contingency
planning phase in a TKA procedure with a TKA contingency plan.
[0019] FIG. 2B is a flow chart representing steps of a debulking
phase in a robotic TKA procedure.
[0020] FIG. 2C is a flow chart representing steps of a finishing
pass phase in a robotic TKA procedure.
[0021] FIG. 2D is a partial perspective view of an exemplary
configuration of bailout holes created in a femur in the
contingency planning phase of FIG. 2A.
[0022] FIG. 2E is a partial perspective view of an alternate
configuration of bailout holes created in a femur in the
contingency planning phase of FIG. 2A.
[0023] FIG. 2F is a partial perspective view of an exemplary
configuration of bailout holes created in a tibia in the
contingency planning phase of FIG. 2A.
[0024] FIG. 2G is a perspective view of a J-block resection
guide.
[0025] FIG. 2H is a perspective view of an alternate embodiment of
a monolithic J-block resection guide.
[0026] FIG. 2I is a front perspective view of a 4-in-1 cutting
guide.
[0027] FIG. 2J is a rear perspective view of the 4-in-1 cutting
guide of FIG. 2I.
[0028] FIG. 2K is a perspective view of a universal resection
guide.
[0029] FIG. 2L is a perspective view of an alternate embodiment of
a monolithic universal resection guide.
[0030] FIG. 3A is a flow chart representing steps of a contingency
planning phase in a bicruciate retaining ("BCR") procedure with a
TKA contingency plan.
[0031] FIG. 3B is a flow chart representing steps of a debulking
phase in a robotic BCR procedure.
[0032] FIG. 3C is a flow chart representing steps of a finishing
pass phase in a robotic BCR procedure.
[0033] FIG. 3D is a partial perspective view of bailout holes
created in a tibia in the contingency planning phase of FIG.
3A.
[0034] FIG. 4A is a flow chart representing steps of a contingency
planning phase in a partial knee replacement ("PKR") procedure with
a TKA contingency procedure.
[0035] FIG. 4B is a flow chart representing steps of a debulking
phase in a robotic PKR procedure.
[0036] FIG. 4C is a flow chart representing steps of a finishing
pass phase in a robotic PKR procedure.
[0037] FIG. 4D is a partial perspective view of bailout holes
created in a femur in the contingency planning phase of FIG.
4A.
[0038] FIG. 4E is a partial perspective view of an alternate
configuration of bailout holes created in a femur in the
contingency planning phase of FIG. 4A.
[0039] FIG. 4F is a perspective view of a femur and tibia after a
robot failed during a robotic PKR procedure.
[0040] FIG. 4G is a perspective view of a distal femoral cut being
manually performed using bailout holes.
[0041] FIG. 4H is a perspective view of the distal femur after
completion of the manual cut illustrated in FIG. 4F.
[0042] FIG. 4I is a perspective view of a proximal tibial cut being
manually performed on the tibia of FIG. 4E using bailout holes.
[0043] FIG. 4J is a perspective view of a one embodiment of a
navigated MIS resection guide with a tracker attached by a tracker
adapter.
[0044] FIG. 4K is a perspective view of the navigated MIS resection
guide of FIG. 4I attached to a femur.
DETAILED DESCRIPTION
[0045] As used herein, the term "distal" means more distant from
the heart and the term "proximal" means closer to the heart. The
term "inferior" means toward the feet and the term "superior" means
towards the head. The term "anterior" means towards the front part
of the body or the face and the term "posterior" means towards the
back of the body. The term "medial" means toward the midline of the
body and the term "lateral" means away from the midline of the
body. Terms including "debulking," "resecting," "machining,"
"finishing," and "bone preparation," are used interchangeably
herein, and all generally refer to the removal and/or reshaping of
bone.
[0046] In the figures, with particular reference to the flow charts
contained therein, a step enclosed in a hexagon indicates a
tool-change step, a step enclosed in a trapezoid indicates a
knee-positioning step, a step in a parallelogram indicates a
registration step, a step enclosed in a diamond may indicate a step
which branches into multiple other possible steps, and a step
enclosed in a rectangle indicates a bone preparation or
trialing/implantation step, unless otherwise indicated. Further, a
step or group of steps enclosed in a broken rectangle indicates
that the steps contained therein may be alternative or optional
steps.
[0047] An exemplary robotically controlled bone preparation system,
or robot 100 for short, that may be used in various joint
arthroplasty procedures is illustrated in FIG. 1. Only a portion of
the robot 100--an arm 110 and a cutting tool 120--is illustrated in
FIG. 1. The robot 100 is shown after having drilled a number of
holes 150 into the femur 130 and tibia 140. The holes 150 are
referred to herein interchangeably as "contingency" or "bailout"
holes, as the holes may only need to be used if the robot 100 fails
and the surgeon needs to manually complete the procedure, using the
bailout holes 150 as reference points. However, holes 150 may also
be interchangeably referred to herein as "plan" points because, as
is described in greater detail below, the bailout holes or plan
points 150 may be useful in situations other than after failure of
the robot 100. Moreover, such plan points 150 may include varying
trajectories such that each hole has a unique angle with respect to
a plane of a joint. For example, each hole may have a unique (x, y,
z) coordinate as an origin point located on the articular surface
of a joint, while the hole also includes a unique (x', y', z')
coordinate where it terminates in bone. Each hole therefore has a
central axis, in which the central axes of the holes may be
parallel or not parallel to one another. Therefore, the holes
generally have a unique position on the articular surface of bone,
the position defining a location and orientation. Because of the
general manner in which the holes are produced, the holes are
generally cylindrically shaped along their length. The diameter and
length or depth of the holes may vary as well depending on the
desired dimensions of the pins or posts that may be coupled to the
holes if required. Further still, as explained in more detail
below, such holes may be used in procedures on other joints,
including ball-and-socket joints, such as the shoulder or hip. As
illustrated in FIG. 1, the robot 100 is in the process of drilling
plan points 150 in preparation for a total knee arthroplasty
("TKA") procedure in which a J-block resection guide is to be used.
As is described in greater below, other configurations of plan
points 150 may be used for other procedures and for other
instruments.
[0048] Without limiting the surgical planning described herein to a
particular joint or a particular procedure for a joint, there are a
number of exemplary joint procedures that may be performed with
surgical plan options geared toward manual completion of the
procedure. For example, a number of knee procedures may be planned
with options or contingencies to the same or alternate knee
procedures. For a partial knee replacement ("PKR") different
surgical plans may facilitate a surgeon completing the procedure
manually as a PKR, or transitioning to a TKA procedure, if such a
transition to manual surgery is desired or required. Similarly, a
patellofemoral joint ("PFJ") procedure may include different
surgical plans that facilitate a surgeon completing the procedure
manually as a PFJ, or transitioning to a TKA procedure, if such a
transition to manual surgery is desired or required. A PFJ-PKR
procedure may include a surgical plan to facilitate a surgeon
completing the procedure as a TKA. Similarly, a TKA procedure may
include a surgical plan that facilitates a surgeon completing the
procedure as a TKA. The intended procedure and the desired
contingency procedure influence the particular configuration of
holes prepared during the procedure, as does the particular jigs,
resection guides or other instruments intended to be used to
complete the contingency procedure, both of which are described in
greater detail below. For knee procedures, contingency plans may be
applicable, for example, to bi-cruciate retaining procedures,
posterior-cruciate retaining procedures, and cruciate sacrificing
procedures. Table 1 below lists a number of exemplary contingency
procedures for different intended procedures that may be possible
for knee joints. It should be noted that the list is non-exhaustive
and other combinations of intended and contingency procedures, such
as BCR to TKA or BCR to BCR, are contemplated within the scope of
the disclosure.
TABLE-US-00001 TABLE 1 Intended Procedure Contingency Procedure
Uni-compartmental PKR PKR TKA PFJ PFJ TKA Bi-compartmental PFJ-PKR
TKA Tri-compartmental TKA TKA
[0049] Steps of a TKA procedure such as in cruciate retaining or
posterior stabilized procedures, for example, are illustrated in
flow charts in FIGS. 2A-C. Specifically FIG. 2A shows a contingency
preparation phase 200a, FIG. 2B shows a debulking phase 200b, and
FIG. 2C shows a finishing phase 200c. In this particular example,
the contingency procedure--a TKA procedure--is the same as the
intended procedure.
[0050] The particular contingency preparation phase 200a
illustrated in FIG. 2A takes the form of creating plan points 150.
Specifically, the contingency preparation phase 200a begins with
step 202, which includes loading a cutting tool 120, such as a burr
or router, on the robot 100. In one example, the cutting tool 120
may be a 2.5 mm burr or router, but other sizes, such as
approximately 1/8 inch or approximately 3.175 mm, and other cutting
tools may be appropriate. In step 204, the knee is put into
flexion, and retractors are positioned in the surgical site to
protect the anterior cruciate ligament ("ACL") and posterior
cruciate ligament ("PCL"), for example. In step 206, registration
is performed with tracker pins, for example. Generally, with
registration, the positions of anatomical landmarks and axes are
digitized as reference for the alignment of instruments, bone cuts,
and the leg. Registration may be performed on the femur 130 and
tibia 140 using trackers 540 (see FIGS. 4J-K) that are fixed to the
bone to allow the NAV system to guide the robot 100. As part of the
registration, for example, the surgeon may touch off key anatomical
landmarks, for example, by using a pointer tool of the NAV system
to mark the medial and lateral epicondyles such that the NAV system
is able to track the location of the key anatomical landmarks
during the procedure. The surgeon may then verify the registration,
for example, by reviewing and confirming the digitized mechanical
axes and analyzing initial leg alignment with respect to range of
motion, varus/valgus misalignment and laxity, and flexion
contracture or hyperextension. Once verified, the surgeon may
accept the surgical plan in step 208.
[0051] The robot 100 drills four plain points 150, for example,
into the femur 130 in step 210. As described above, in addition to
the intended and the contingency procedure, the number and position
of the plan points 150 may also depend on the particular
instruments intended for use with the procedure. For example, a
different configuration of plan points 150 may be used if a femoral
resection is to be guided by a J-block resection guide, a universal
resection guide, a navigated MIS guide, or any other suitable
guide. As illustrated in FIG. 2D, the four plan points 150 in the
femur 130 may include two anterolateral plan points 150a and two
distal plan points 150b. In another embodiment, step 210 may entail
drilling two anterior plan points 150a and two distal plan points
150b as illustrated in FIG. 2E. In step 212, the robot 100 may
drill four plan points 150 into the tibia 140. Specifically, as
illustrated in FIG. 2F, the plan points 150 may include two
proximal plan points 150c. Step 212 may also include the robot 100
drilling two proximal-anterior plan points 150d in the tibia 150.
Although it is preferred for the robot 100 to create the plan
points 150, it is contemplated that the plan points 150 may be
created manually for all the surgical plans described herein.
[0052] The plan points 150 may provide references for the surgeon
to use if the robot 100 should fail later in the procedure, or to
otherwise aid a surgeon in manually completing a procedure. For
example, in the configuration illustrated in FIG. 2D, the two
anterolateral plan points 150a may be configured to align with
guide holes 650a in a J-block resection guide 600 as illustrated in
FIG. 2G. Fixation pins may be placed through each of a pair of
guide holes 650a and further into plan points 150a to fix the
J-block 600 to the bone. J-block resection guide 600 may be
generally "J"-shaped and include a number of sets or pairs of guide
holes, each set being a different distance from a cutting slot 610.
J-block resection guide 600 may also include additional holes, such
as cross-pin hole 620, to provide additional stability when fixing
the resection guide to the bone. An alternate monolithic J-block
600' as illustrated in FIG. 2H, may be used instead of J-block 600.
Rather than having pairs or sets of holes 650a, J-block 600' has a
pair of posts 650a' that are configured to be inserted into plan
points 150a. The two distal femoral plan points 150b may be sized
and configured to mate with a 4-in-1 cutting block 700, as
illustrated in FIGS. 2I-J and as is known in the art. In
particular, posts 750b may be used to attach the 4-in-1 cutting
block 700 to the femur 130.
[0053] The configuration of plan points 150 illustrated in FIG. 2E
may be configured to align with guide holes 850a in a universal
resection guide 800, as illustrated in FIG. 8K. Fixation pins may
be placed through each of a pair of guide holes 850a and further
into plan points 150a to fix the universal resection guide 800 to
the bone. Universal resection guide 800 may include a number of
sets or pairs of guide holes 850a, each set being a different
distance from a top surface 810. Universal resection guide 800 may
also include additional holes, such as cross-pin holes 820, to
provide additional stability when fixing the resection guide to the
bone. An alternate monolithic universal resection guide 800' as
illustrated in FIG. 2L, may be used instead of universal resection
guide 800. Rather than having pairs or sets of holes 850a,
universal resection guide 800' has a pair of posts 850a' that are
configured to be inserted into plan points 150a. As in the previous
embodiment, the two distal femoral plan points 150b may be sized
and configured to mate with 4-in-1 cutting block 700.
[0054] Referring again to FIG. 2F, the two proximal-anterior tibial
plan points 150d may be sized and positioned to mate with a
proximal tibial resection guide to facilitate the proximal tibial
cut. The two proximal tibial plan points 150c, which may be
optional, may be sized and shaped to mate with a tibial template
for rotation assessment and trial reduction.
[0055] The remaining steps in the cruciate retaining or posterior
stabilized TKA procedure are described immediately below according
to a successful procedure in which the robot 100 completes the
procedure. In the debulking phase 200b, illustrated in FIG. 2B, the
first step 214 is to load (or switch to) a cutting tool, such as a
barrel burr, onto the robot 100. The cutting tool may be, for
example, a 6, 8, or 10 mm barrel burr. However, other sizes and
other cutting tools may also be appropriate. In step 216, the
posterior and distal femur 130 are debulked with chamfer cuts and
the proximal tibia is debulked. The debulking may be done
simultaneously or sequentially. Tissue balancing may be done in
step 218 if required. If not required, the surgeon may move to the
baseplate step 220. If required, the surgeon may perform tissue or
ligament balancing as is known in the art. For example, the surgeon
may check the tensioning of the knee in flexion and extension, and
check the alignment of the mechanical axis using a manual
distractor and/or the graphic user interface of the NAV system. If
the intraoperative measurements are acceptable, the surgeon may
move to the baseplate step 220. If they are not acceptable, the
surgeon may perform soft tissue release. Following the soft tissue
release, the surgeon may repeat step 218 for other degrees of
freedom of the knee. Alternately, if additional bone surface
preparation is required, the surgeon may return to the debulking
step 216 after performing the tissue release. Once the surgeon is
satisfied with the tissue balancing step 218, he may advance to the
baseplate step 220.
[0056] From the baseplate step 220, the surgeon may check and
verify rotation using a tibial template in step 222. Depending on
the type of baseplate being used, the tibia 140 may need to be
further prepared prior to approving rotation. For example, if a
universal baseplate is to be used, the surgeon may debulk the tibia
for accepting the universal stem of the baseplate. Alternatively,
if a primary baseplate is to be used, the surgeon may move directly
from baseplate step 220 to step 222 to approve rotation using a
tibial template. Once rotation is approved, the knee is placed in
extension in step 224 and retractors and a patella clamp are
positioned in the surgical site as necessary and as is known in the
art. In step 226, the surgeon removes the tibial tracker 540 and
attached the patella clamp with its associated tracker and performs
registration for the NAV system, as is also known in the art.
Finally, in step 228, the patella is debulked, bringing the
debulking phase 200b to an end.
[0057] In the first step 230 of the finishing pass phase 200c, as
illustrated in FIG. 2C, a cutting tool, such as a finishing router,
is loaded onto the robot 100. The router may be, for example, a 2.5
mm router, but other sizes and other cutting tools may be
appropriate. In step 232, the patella is finished by the robot, and
fixation holes for the pegs in the patellar implant are created in
the patella. At this point, in step 234, the patella clamp and
tracker 540 are removed and the tibial tracker is turned on. The
anterior femoral surface is finished in step 236 with the robot.
Alternatively, the anterior femoral surface may be finished earlier
with the larger cutting tool.
[0058] After the femoral surface is finished, the knee is put into
flexion in step 238 and retractors are positioned in the surgical
site. Once in position, in step 240, the distal/posterior femur and
proximal tibia are posed in flexion, between approximately 90 and
approximately 110 degrees. Femoral preparation is completed,
including, for example, preparing the "box" for posterior
stabilized TKA procedures. Next, in step 242, the tibial insert
thickness is selected using the tibial template. Once selected, the
tibial keel is prepared in step 244. The tibial keel may be, for
example, prepared at full depth in step 246 if cement is used, or
at partial depth in step 248 if the implantation will be
cementless. One the tibial keel is prepared, the surgeon may
complete the procedure by trialing the implant components in step
250 to verify proper size and position, create the femoral pegs
using the robot 100 in step 252, and implanting the components in
step 254.
[0059] In the procedure described above for cruciate retaining or
posterior stabilized TKA, if the robot 100 and NAV system fail
during the procedure after the robot has entered the debulking
phase 200b, the surgeon may continue the procedure manually using
the plan points (or bailout holes) 150. Specifically, depending on
the configuration of plan points 150 prepared, the surgeon may
attach a distal femoral resection guide to the femur. For example,
with reference to FIG. 2D, the surgeon may attach a J-block
resection guide 600 or 600' to the femur 130 using anterolateral
femoral plan points 150a. This or a similar configuration of plan
points 150 may also allow use of a navigated MIS jig 500,
illustrated in FIGS. 4F-K. Alternately, with reference to FIG. 2E,
the surgeon may attach a universal resection guide 800 or 800' to
the femur 130 using anterior plan points 150a. Once attached, the
surgeon may make the femoral distal cut using the guide. Referring
to FIGS. 2D-E, following the femoral distal cut, the surgeon may
attach, for example, a 4-in-1 cutting block 700 to the femur using
the distal femoral plan points 150b. Once attached, the surgeon may
make additional femoral cuts including, for example, an anterior
cut, a posterior cut, and anterior and posterior chamfer cuts using
the aforementioned 4-in-1 guide 700. Similarly, the surgeon may
attach a tibial resection guide to the tibia 140 using the
proximal-anterior tibial plan points 150d. Finally, the tibial
template may be attached to the tibia 140 using proximal tibial
plan points 150c for rotation assessment and trial reduction. A
number of intermediate steps to those described directly above are
not explicitly detailed here, as they may be similar to those
described above with relation to the complete successful robotic
procedure, or are otherwise known in the art. Because the plan
points 150 are created to correspond to traditional components used
in manual TKA procedures, a surgeon will be able to relatively
seamlessly transition from a robotic TKA procedure to a manual TKA
procedure in the case the robot 100 fails.
[0060] In fact, the robot 100 may even be used to create the plan
points 150 when the surgeon intends to perform a manual TKA
procedure and has no intention to use the robot 100 after the plan
points 150 are created. For example, a surgeon may prefer to have
the robot 100 pre-drill the plan points 150, which would be used
not as "bailout" holes in case a contingency plan needs
implementation, but rather in a case in which a manual procedure is
intended after the robot pre-drills the holes. This may be
preferred, for example, because the plan points 150 made by the
robot 100 may provide a way to set up highly accurate cuts using a
jig, such as the J-block or universal resection guides 600 (or
600'), 800 (or 800'). Further, the use of the robot 100 to
implement these plan points 150 may allow a predetermined surgical
plan to be used to determine the location of the holes and thus the
positioning of the jigs and ultimately the precise location of the
cuts. And this is not limited to drilling holes. For example, robot
100 may machine the bone to have any number of features that
correspond to a surgical instrument or implant. For example, the
robot 100 may machine the bone to have a precisely curved surface
to correspond to a curved surface of an implant. Machining such a
curved surface without the use of a robot may be impossible to
accurately reproduce by hand. For example, the robot 100 may
machine the curved surface such that the machined surface of the
bone corresponds to an axis of rotation of an implant to be
implanted onto the bone. Once the surface is machined by the robot
100, the user may manually complete the procedure by attaching the
implant to the bone and performing any additional required steps.
Still further, the robot 100 may create curved holes in the bone to
accept, for example, a curved keel of a prosthetic implant. It may
only be possible to accurately reproduce such a curved hole that
corresponds to a curved structure of an implant via the robot 100,
which may be impossible to create manually. In each of the above
examples, the machining by the robot 100 is not used strictly as a
contingency plan. Rather, the robot 100 is being used to provide a
benefit of robotic machining including, for example accuracy,
speed, and/or reproducibility. Despite use of the robot 100, the
intent from the outset is to manually complete the procedure
without further use of the robot 100 after the initial machining of
the bone by the robot 100.
[0061] Plan points 150 may also provide other benefits, such as
confirming or rescuing registration. As noted above in connection
with step 206 of FIG. 2A, a user may perform registration to
digitize the positions of anatomical landmarks and axes as
reference for the alignment of instruments, bone cuts, and the leg.
Subsequent to registration, a user may reference plan points 150 to
check the accuracy of registration and also to rescue a compromised
registration, for example in the event a tracker 540 has been moved
inadvertently. To accomplish this, the user may place the pointer
tool in the desired plan point 150 and visualize the location of
the hole and pointer tool on the NAV screen as it relates to the
physical anatomy in situ. If the screen image does not match the
tangible anatomy under direct visualization the user may determine
that the tracker 540 likely moved subsequent to the step of
verifying the registration. The user may then direct the guidance
system to calculate the difference between the altered tracker
location and/or coordinate system and the previous registration,
and adjust accordingly so that the altered tracker location and/or
coordinate system can be used to complete the procedure
successfully. After the calculations are completed and the
coordinate systems are adjusted, the procedure can be completed as
planned. The above described procedure of registration
verification, as well as registration rescue, may apply with equal
force to the other specific surgical plans described herein.
[0062] Steps of a BCR procedure with a contingency plan of a TKA
procedure are illustrated in flow charts in FIGS. 3A-C.
Specifically FIG. 3A shows a contingency preparation phase 300a,
FIG. 3B shows a debulking phase 300b, and FIG. 3C shows a finishing
phase 300c.
[0063] The particular contingency preparation phase 300a
illustrated in FIG. 3A takes the form of creating plan points 150.
The configuration of the femoral plan points 150 may be, for
example, the same as illustrated in FIG. 2D or FIG. 2E, depending
on the particular instrumentation desired for use. The
configuration of the tibial plan points 150 may be, for example,
the same as illustrated in FIG. 2F or may take the configuration
illustrated in FIG. 3D. Specifically, the contingency preparation
phase 300a begins with step 302, which includes loading a cutting
tool 120, such as a router, on the robot 100. In one example, the
cutting tool 120 may be a 2.5 mm router, but other sizes, such as
approximately 1/8 inch or approximately 3.175 mm, and other cutting
tools may be appropriate. In step 304, the knee is put into
flexion, and retractors are positioned in the surgical site to
protect the ACL and PCL. In step 306, registration is performed
using femur 130 and tibia 140 trackers 540 to allow the NAV system
to guide the robot 100. The surgeon may accept the surgical plan in
step 308 if satisfied, touching off key landmarks and verifying
placement.
[0064] The robot 100 drills four plan points 150 into the femur 130
in step 310. Specifically, as illustrated in, and described in
relation to, FIGS. 2D-E, the four plan points 150 in the femur 130
may include two anterolateral plan points 150a and two distal plan
points 150b (FIG. 2D) or two anterior plan points 150a and two
distal plan points 150b (FIG. 2E). In step 312, the robot 100 may
drill two proximal-anterior plan points 150d into the tibia 140.
Alternately, the robot 100 may drill two proximal-anterior plan
points 150d and two proximal plan points 150c in the tibia 140, as
illustrated in, and described in relation to, FIG. 2F.
[0065] As described with relation to the contingency preparation
phase 200a for the posterior stabilized of cruciate retaining TKA
procedure, the plan points 150 for the BCR to TKA procedure may
provide references for the surgeon to use if the robot 100 should
fail later in the procedure and the procedure is to be completed as
a TKA, or if the surgeon otherwise decides to complete the
procedure manually as a TKA.
[0066] The remaining steps in the BCR to TKA procedure are
described immediately below according to a successful BCR procedure
in which the robot 100 completes the procedure. In the debulking
phase 300b, illustrated in FIG. 3B, the first step 314 is to load
(or switch to) a cutting tool, such as a barrel burr, onto the
robot 100. The cutting tool may be, for example, a 6, 8, or 10 mm
barrel burr. However, other sizes and other cutting tools may also
be appropriate. In step 316, the posterior and distal femur 130 are
debulked with chamfer cuts and the proximal tibia is debulked. The
debulking may be done simultaneously or sequentially. Tissue
balancing may be done in step 318 if required, although balancing
may not be recommended in a BCR procedure. Following the tissue
balancing step 318, the surgeon may perform an intraoperative
assessment of the surgical plan and make changes if necessary in
step 320. After step 320, or after step 316 if tissue balancing is
not required, the surgeon may put the knee in flexion in step 322,
attaching retractors and positioning a patella clamp as necessary.
The tibial tracker 540 is turned off in step 324 and the patella
clamp with tracker is attached and registered for the NAV system.
The robot 100 debulks the patella in step 326, bringing the
debulking phase 300b to an end.
[0067] In the first step 328 of the finishing pass phase 300c, as
illustrated in FIG. 3C, a cutting tool, such as a finishing router,
is loaded onto the robot 100. The router may be, for example, a 2.5
mm router, but other sizes and other cutting tools may be
appropriate. In step 330, the patella is finished by the robot, and
fixation holes for the pegs in the patellar implant are created in
the patella. At this point, in step 332, the patella clamp and
tracker 540 are removed and the tibial tracker is reattached. The
anterior femoral surface is finished in step 334 with the
robot.
[0068] After the femoral surface is finished, the knee is put into
flexion in step 336 and retractors are positioned in the surgical
site to protect the ACL and PCL. Once in position, in step 240, the
distal/posterior femur and proximal tibia are posed in flexion,
between approximately 90 and approximately 110 degrees. In step
338, femoral preparation is completed, including, for example,
preparation of femoral pegs. Tibial preparation is also completed
step 338, including, for example, preparation of the tibial
plateau, the tibial eminence periphery, and the tibial keel. Next,
in step 340, the tibial insert thickness is selected using the
tibial template, as is known in the art. Once selected, the surgeon
may complete the procedure by trialing the implant components in
step 342 to verify proper size and position, and implanting the
components in step 344.
[0069] In the procedure described above for BCR to TKA, if the
robot 100 and NAV system fail during the procedure after the robot
has entered the debulking phase 300b, the surgeon may continue the
procedure manually as a TKA using the plan points as bailout holes
150. This contingency procedure would be essentially the same as
described for the TKA to TKA procedure above. It should be noted
that the BCR procedure may be planned with plan points 150 such
that the contingency procedure is also a BCR procedure. Similar as
to what is described above, plan points 150 may be used for
completing a procedure manually, even in cases where the robot 100
does not fail and the original plan includes manual completion.
[0070] Steps of a PKR procedure are illustrated in flow charts in
FIGS. 4A-C. Specifically FIG. 4A shows a contingency preparation
phase 400a, FIG. 4B shows a debulking phase 400b, and FIG. 4C shows
a finishing phase 400c.
[0071] The particular contingency preparation phase 400a
illustrated in FIG. 4A takes the form of creating plan points 150,
such that a PKR procedure may be completed as a TKA procedure. It
should be noted that a different configuration of plan points 150
may be used such that an intended PKR procedure may still be
completed as a PKR procedure if the robot 100 fails during the
procedure, or if the surgeon otherwise desires to complete the
procedure manually. For example, for a PKR to PKR procedure, four
plan points may be created in the femur (not illustrated) to
interact with a distal resection guide and a 2-in-1 cutting block.
For the PKR to TKA procedure, the plan points may take the
configurations, for example, as illustrated in FIG. 4D or FIG. 4E.
Specifically, the contingency preparation phase 400a begins with
step 402, which includes loading a cutting tool 120, such as a
router, on the robot 100. In one example, the cutting tool 120 may
be a 2.5 mm burr, but other sizes, such as approximately 1/8 inch
or approximately 3.175 mm, and other cutting tools may be
appropriate. In step 404, the knee is put into flexion, and
retractors are positioned in the surgical site. In step 406,
registration is performed using femur 130 and tibia 140 trackers
540 to allow the NAV system to guide the robot 100. The surgeon may
accept the surgical plan in step 408 if satisfied, touching off key
landmarks and verifying placement.
[0072] The robot 100 drills three plan points 150 into the femur
130 in step 410. As described above, the particular configuration
of plan points 150 may depend on the instruments to be used if the
procedure is to be completed manually. As illustrated in FIG. 4D,
the three plan points 150 in the femur 130 may include two
anterolateral plan points 150a and a distal plan point 150b. All
three plan points 150 in the femur 130 are drilled in the
particular compartment being replaced. In another embodiment, step
410 may entail drilling two anterior plan points 150a and a distal
plan point 150b, as illustrated in FIG. 4E. In step 412, the robot
100 drills two (FIG. 3D) or four (FIG. 2F) plan points 150 into the
tibia 140, depending on the preference of the surgeon.
[0073] As described with relation to the contingency preparation
phases 200a and 300b for the different TKA procedures, the plan
points 150 for the PKR procedure may provide references for the
surgeon to use if the robot 100 should fail later in the procedure,
or if the surgeon otherwise desires to complete the surgical plan
manually. For example, the two anterolateral femoral plan points
150a (FIG. 4D) may be sized and positioned to mate with a J-block
resection guide 600 or 600', or with a navigated MIS resection
guide 500, as shown in FIGS. 4F-K, for example. J-block resection
guides 600 are known in the art and described more fully in U.S.
Patent Publication No. 2005/0171545, the entire contents of which
are hereby incorporated by reference herein. Also as described in
relation to other embodiments herein, according to the
configuration of plan points 150 illustrated in FIG. 4E, two
anterior plan points may be configured to facilitate attachment of
a universal resection guide 800 or 800' to the femur 130. In the
configuration of plan points 150 illustrated in both FIGS. 4D-E, a
distal plan point 150b may be configured to mate with 2-in-1
resection guide (not illustrated). The two anterior tibial plan
points 150d may be sized and positioned to mate with a proximal
tibial resection guide.
[0074] The remaining steps in the PKR procedure are described
immediately below according to a successful procedure in which the
robot 100 completes the procedure. In the debulking phase 400b,
illustrated in FIG. 4B, the first step 414 is to load (or switch
to) a cutting tool, such as a barrel burr, onto the robot 100. The
cutting tool may be, for example, a 6, 8, or 10 mm barrel burr.
However, other sizes and other cutting tools may also be
appropriate. In step 416, the distal and posterior chamfer cuts are
made on the femur 130. Following these cuts, the proximal tibia 140
and the posterior femur are sequentially debulked. Tissue balancing
may be done in step 418 if required. If not required, the surgeon
may move to the finishing pass phase 400c. If required, the surgeon
may perform tissue balancing as is known in the art. For example,
the surgeon may check the tensioning of the knee in flexion and
extension, and check the alignment of the mechanical axis using a
manual distractor and/or the graphic user interface of the NAV
system. If the intraoperative force measurements are acceptable,
the surgeon may move to the finishing pass phase 400c. If they are
not acceptable, the surgeon may perform soft tissue release.
Following the soft tissue release, the surgeon may repeat step 418
for other degrees of freedom of the knee. Alternately, if
additional bone surface preparation is required, the surgeon may
return to the debulking step 416 after performing the tissue
release. Once the surgeon is satisfied with the tissue balancing
step 418, he may advance to the finishing pass phase 400c.
[0075] In the first step 420 of the finishing pass phase 400c, as
illustrated in FIG. 4C, a cutting tool, such as a finishing router,
is loaded onto the robot 100. The router may be, for example, a 2.5
mm router, but other sizes and other cutting tools may be
appropriate. In step 422, a finishing pass on the femur 130 is
completed, for example with the distal/posterior femur and proximal
tibia being posed in flexion, between approximately 90 and
approximately 110 degrees. In step 424, the proximal tibial
preparation is completed, including, for example, preparation of
tibial pegs. Finally, the surgeon may complete the procedure by
trialing the implant components in step 426 to verify proper size
and position, and implanting the components in step 428.
[0076] In the procedure described above for PKR, if the robot 100
and NAV system fail during the procedure after the robot has
entered the debulking phase 400b, the surgeon may continue the
procedure manually using the plan points 150 as bailout holes, for
example as illustrated in FIG. 4D or 4E. Specifically, with
reference to FIG. 4F, a femur 130 and tibia 140 are illustrated
after plan points 150 are created and at a point which the surgeon
decides to complete the procedure manually, in the illustrated case
because of a failure of the robot 100. FIG. 4F illustrates the
position of the femur 130, with distal femoral plan point 150b
visible. Anterolateral plan points configured to mate with a
navigated MIS resection guide, similar to the anterolateral plan
points 150a of FIG. 4D, are not visible, but fixation pins 510
extend through the navigated MIS resection guide 500 and into the
anterolateral plan points 150a. Partially visible in FIG. 4F is
another navigated MIS resection guide 500 with tracker adapter 502
(see FIGS. 4J-K) attached to the tibia 140, described in greater
detail below. FIG. 4G illustrates a cutting blade 520 being used in
conjunction with the navigated MIS resection guide 500 which is
held in place by the fixation pins 510 inserted into the
anterolateral plan points 150a. The cutting blade 520 is used to
manually complete the distal femoral cut, as illustrated in FIG.
4H. FIG. 4I illustrates the tibia 140 with a navigated MIS
resection guide 500 attached. Fixation pins 510 are inserted into
tibial bailout holes to hold the navigated MIS resection guide 500
in place while a cutting blade 520 is used to resect the proximal
tibia 130. As can be seen despite the transition from a robotic to
manual procedure mid-surgery, the intended PKR robotic procedure
can seamlessly be transitioned into a successful manual TKA
procedure by use of the plan points 150 created during the
contingency planning phase 400a.
[0077] It should be noted that, although particular configurations
of plan points are illustrated herein for use with particular types
of resection guides, the configuration of the plan points are, at
least in part, dictated by the particular jigs, resection guides,
or other instruments that need to be attached to the bone using the
bailout holes. As such, the methods described herein may be
expanded to be used with many other particular resection guides,
for example, without departing from the spirit of the
invention.
[0078] It may also be the case that the robot 100 fails
mid-surgery, but the NAV system continues functioning properly. In
this scenario, the surgeon may complete the surgery in a similar
manner as described directly above, with the aid of the NAV system.
For example, FIG. 4J illustrates navigated MIS resection guide 500
with a tracker adapter 502 and tracker 540 attached. The assembly
attached to the femur 130 with fixation pins 510 is illustrated in
FIG. 4K. Essentially, after the robot 100 fails, the surgery would
be completed much as described directly above, but with the
additional aid of the NAV system facilitating, for example, the
location of the resections. Although surgical procedures using
guidance from NAV systems is known in the art, for example in U.S.
Pat. Nos. 7,392,076 and 8,382,765, the entire contents of which are
hereby incorporated by reference herein, it would be desirable for
a surgeon to be able to seamlessly transition from a robotic
surgical procedure to a NAV guided manual procedure in the case the
robot 100 fails but the NAV system is still operational.
[0079] It should be noted that, throughout this disclosure,
reference has been made to particular configurations of plan points
or bailout holes 150. It should be understood that other
configurations are possible, depending on the particular surgical
procedure being performed and the particular device to be used with
the plan points 150. For example, the plan points 150 may be
positioned differently than shown herein to match with the intended
location of fixation pins of any appropriate jig to be used in the
case of robotic failure. However, as described above, the plan
points 150 may also be used in the case in which robotic surgery is
not contemplated, but rather wherein a surgeon desires a robot 100
to create plan points 150 that correspond to one or more jigs to be
used with the intended manual surgical procedure.
[0080] Although the invention herein has been described with
reference to particular embodiments, it is to be understood that
these embodiments are merely illustrative of the principles and
applications of the present invention. It is therefore to be
understood that numerous modifications may be made to the
illustrative embodiments and that other arrangements may be devised
without departing from the spirit and scope of the present
invention as defined by the appended claims.
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