Note: Descriptions are shown in the official language in which they were submitted.
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KNEE INSTRUMENTS AND METHODS
TECHNICAL FIELD
[0001] The present disclosure relates to instruments and methods to improve
femoral and
tibial alignment during knee arthroplasty. More specifically, the present
disclosure relates to
instruments and methods to reference and align with the anterior distal
femoral cortex, the
mechanical axis of the leg, and Whiteside's line (while intact, prior to any
distal femoral
resection). While this disclosure is made in the context of knee arthroplasty,
the principles are
applicable to alignment during other arthroplasty procedures.
BACKGROUND
[0002] Traditional total knee arthroplasty instruments utilize
intrannedullary instruments to
determine proper distal femur saw cut alignment, and extrannedullary
instruments to align the
saw cut for the proximal tibia. Therefore it is acceptable to prepare the
distal femur separate
from the proximal tibia. There exists no conjoined effort to cut the distal
femur and the
proximal tibia as the single lower extremity body part which constitutes the
knee joint.
[0003] This contemporary instrumentation process violates the principles
established by
Insall in the 1970s. Popular total knee arthroplasty instruments teaches this
inexact
intrannedullary instrument process because it is simpler to teach, understand
and utilize by
most surgeons.
[0004] Dr. Insall recognized the need for external rotation (ER) of the
femoral component
when performing a total knee arthroplasty (TKA). In 1990 Dr. Insall attributed
the need for
approximately 3 degrees of ER to an "abundance of soft tissue in the
posteronnedial corner of
the knee."
[0005] Indeed in the absence of this prescribed ER of the femoral component
1) patellar
tracking will be unbalanced, related to the trochlear groove and 2) the medial
compartment will
be compressed significantly greater than the lateral compartment with the knee
flexed beyond
40 degrees and 3) the patella would track laterally.
[0006] The reason for alteration of the normal morphology of the distal
femur when
performing a TKA is not well understood.
[0007] The reason for the need to externally rotate the femoral condyle
approximately 3
degrees relative to the normal morphology of the femoral condyles is the clue
to surgical
alteration of normal morphology of the proximal tibia.
[0008] Normal Anatomy of the Proximal Tibia
[0009] As is well known, in a lateral xray of a normal proximal tibia, the
plane of the medial
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tibial plateau exists approximately 3 mm more distal than the lateral tibial
plateau.
[0010] Evident in a CAT scan of a normal knee is the elevation difference
between the
planes of the two tibial plateaus.
[0011] If a saw cut is made at the proximal tibia, at a right angle to the
vertical axis of the
tibia, the medial tibial compartment will be elevated relative to the lateral
tibial plateau. This
relative elevation will, in turn, elevate the medial femoral condyle,
necessitating removal of an
equal amount of posterior medial femoral condyle (equal to the relative
elevation of the medial
tibial plateau) in order to maintain proper tracking of the patellar
throughout flexion and
extension of the knee. It is the external rotation of approximately 3 degrees
(3 mm) that
accomplishes about 3nnnn more removal of the condyle on the medial side than
the lateral side.
[0012] The most common adjustment position for "external rotation guides"
is 3 degrees.
This position will remove about 3nnnn more off the medial femoral condyle than
the lateral
femoral condyle. The reality is, and therefore the error is, that condylar and
plateau articular
cartilage wear, and differences in plateau height between the medial and
lateral plateaus, will
require external rotation adjustments between 1 degree and 6 degrees in order
to balance
compression forces in the medial and lateral compartments for both flexion and
extension.
[0013] It is only after equal compartment compression is accomplished
through proper
external rotation that proper ligament releases can be accomplished.
[0014] Method for Getting External Rotation Right
[0015] Equal compression of the medial and lateral compartments can only be
obtained by
causing the posterior femoral condylar cut to be parallel to the proximal
tibial cut.
[0016] To accomplish this:
[0017] Pin the tibial cut guide in place with the tibial alignment rod
centering distally over
the middle of the plafond. The plafond is the ceiling of the ankle joint, that
is, the articular
surface of the distal end of the tibia.
[0018] After resecting the distal femur, place the 4-in-1 femoral cut guide
in place over the
cut surface of the distal femur. Hang the 4-in-1 cutting guide on a centrally
placed pin on
Whiteside's line located just below the cut slot for the anterior femoral
resection. This cut slot
location references the distal/anterior femoral cortex for proper anterior
resection. The
centrally placed pin may optionally be replaced by a protruding post located
on the bone-
contacting side of the 4-in-1 cut guide that fits into a corresponding hole in
the femur.
[0019] Utilizing the proper sized 4-in-1 cut guide, this guide is now
"rotated" until the
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posterior cut slot is parallel with the cut slot on the tibial cut guide.
[0020] Appropriate fixation pins/screws secure the femoral and tibial cut
guides. All cuts
can now be made, assuring proper patellar tracking.
[0021] Equal and rectangular gaps can be expected in both flexion and
extension. Soft
tissue releases are now performed to further balance compression forces in the
medial and
lateral compartments.
[0022] At least the following aspects of this disclosure are believed to be
novel and non-
obvious contributions over the prior art of knee arthroplasty:
[0023] Reference of distal anterior femur (DAF) and exact location of
femoral head to
accomplish exact knowledge of 1) varus/valgus of distal femoral cut, and 2)
flexion/extension of
anterior and posterior femoral cuts. Both data points are contained in the
position of a distal
femoral pin or hole.
[0024] Determination of proper External Rotation of femur by "hanging" the
upper-center
portion of a 4-in-1 femoral cutting block on the distal femoral pin, which is
in the center of the
trochlear groove. The proximal/distal axis through the center of the block is
aligned with the
longitudinal axis of the tibia, which aligns the trochlear groove of the femur
(Whiteside's line)
with the axis of the tibia at 90 degrees flexion of the knee. The distal
femoral pin may optionally
be replaced by a protruding post located on the bone-contacting side of the 4-
in-1 cut guide
that fits into a corresponding hole in the femur.
[0025] With proper ER of the femoral component, the posterior femoral cut
and the
proximal tibial cut will be parallel at 90 degrees knee flexion. Therefore the
4-in-1 femoral
cutting block can be extended to a 5-in-1 cutting block by adding the proximal
tibial cut slot.
[0026] The 5-in-1 (effective) block is attached superiorly (proximally) at
the distal femoral
pin or hole and distally to the tibial alignment rod extending to the middle
of the ankle. The
patellar will now track properly.
[0027] With the rectangular gap at the femur and tibia, equal compression
will exist
between medial and lateral compartments of the knee both in flexion and
extension.
[0028] Other:
[0029] Finding the femoral head.
[0030] Bar fixed to operating table over the area of the femoral head with
goal post
marker/target.
[0031] Ultrasound method of locating femoral head.
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[0032] Guide to reference DAF and then connect to femoral head goal
post/target to
determine distal femoral pin location. Arthroscopic procedure contemplated.
[0033] Adjustable 4-in-1 femoral cut guide.
[0034] This disclosure teaches bony and soft tissue preparation of the knee
joint utilizing
instruments and techniques consistent with proven total knee arthroplasty
instruments
principles.
SUMMARY
[0035] The various systems and methods of the present technology have been
developed in
response to the present state of the art, and in particular, in response to
the problems and
needs in the art that have not yet been fully solved by currently available
knee arthroplasty
instrument systems and methods. The systems and methods of the present
technology may
provide more objective, repeatable alignment relative to important
bionnechanical features,
compared to current systems and methods.
[0036] More specifically, the present disclosure relates to instruments and
methods to
reference and align with the anterior distal femoral cortex, the mechanical
axis of the leg, and
Whiteside's line (while intact, prior to any distal femoral resection). The
anterior femoral
resection is aligned in the same plane as the anterior distal femoral cortex.
The center of the
femoral head, the medial/lateral center of the distal femur, the
medial/lateral center of the
proximal tibia, and the second toe, medial/lateral center of the ankle, or
anterior tibial spine or
crest are all simultaneously aligned to the mechanical axis of the leg while
the leg is in full
extension and the knee joint is distracted. The distal femoral and proximal
tibial resections are
aligned relative to the mechanical axis of the leg. Since the distal femoral
and proximal tibial
resections may be made with the leg in full extension, a much smaller incision
may be required,
particularly in the quadriceps region. An eight to ten inch long incision,
typical of the current
state of the art, may be shortened to about six inches, with most of the
savings occurring
proximally in the quadriceps region. Whiteside's line is referenced while the
distal femur is
intact, before any distal femoral resection, and the anterior and posterior
femoral resections
and chamfer cuts are aligned to this reference using a jig.
[0037] The systems and methods disclosed herein provide a simple and fast
way to
objectively and precisely align the knee joint during arthroplasty procedures.
This is inherently
advantageous because nnalalignnnent predisposes a reconstructed knee to
premature failure.
This is particularly advantageous for those surgeons who must perform knee
arthroplasty from
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time to time, but whose knee arthroplasty procedure volume is low. Eighty
percent of knee
arthroplasty procedures are performed by surgeons who do no more than two knee
arthroplasty procedures per month.
[0038] The systems disclosed herein provide a cost-effective mechanical
alternative to
surgical navigation systems, particularly because the disclosed systems
include components
that are readily made as disposable items. The femoral and tibial alignment
components, for
example, are contemplated to be disposable items.
BRIEF DESCRIPTION OF THE DRAWINGS
[0039] Exemplary embodiments of the technology will become more fully
apparent from
the following description and appended claims, taken in conjunction with the
accompanying
drawings. Understanding that these drawings depict only exemplary embodiments
and are,
therefore, not to be considered limiting of the scope of the technology, the
exemplary
embodiments will be described with additional specificity and detail through
use of the
accompanying drawings in which:
[0040] FIG. 1 is a perspective view of a femur, tibia, and fibula with a
foot receiver and a
lower bar of a foot holder assembly;
[0041] FIG. 2 is a perspective view of the femur, tibia, fibula, foot
receiver, and lower bar of
FIG. 1 with a femoral support arm assembly;
[0042] FIG. 3 is a perspective view of the femur, tibia, fibula, foot
receiver, lower bar, and
femoral support arm assembly of FIG. 2 with a femoral head finder coupled to
the femoral
support arm assembly;
[0043] FIG. 4 is a perspective view of the femur, tibia, fibula, foot
receiver, lower bar,
femoral support arm assembly, and femoral head finder of FIG. 3 with a collar
coupled to the
femoral support arm assembly next to the femoral head finder;
[0044] FIG. 5 is a perspective view of the femur, tibia, fibula, foot
receiver, lower bar,
femoral support arm assembly, and collar of FIG. 4 with a target clamp
assembly coupled to the
femoral support arm assembly next to the collar;
[0045] FIG. 6 is a perspective view of the femur, tibia, fibula, foot
receiver, lower bar,
femoral support arm assembly, collar, and target clamp assembly of FIG. 5 with
a complete foot
holder assembly including a bridge, target mounting block, dovetail lock,
target, and
thumbscrew coupled to the lower bar and the foot receiver;
[0046] FIG. 7A is a perspective view of the foot holder assembly of FIG. 6;
FIG. 7B is an
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exploded perspective view of the foot holder assembly of FIG. 6; and FIG. 7C
is another
exploded perspective view of the foot holder assembly of FIG. 6 from a
different direction;
[0047] FIG. 8A is a perspective view of the femur, tibia, fibula, femoral
support arm
assembly, collar, target clamp assembly, and foot holder assembly of FIG. 6
with a femoral pin
guide assembly coupled to the anterior distal femur; and FIG. 88 is a detail
perspective view of
the femur, tibia, fibula, and femoral pin guide assembly of FIG. 8A; and
[0048] FIG. 9A is a perspective view of the femoral pin guide assembly of
FIG. 8A; FIG. 913;
and FIG. 9C; FIG. 98 is an exploded perspective view of the femoral pin guide
assembly of FIG.
8A; and FIG. 98 is another exploded perspective view of the femoral pin guide
assembly of FIG.
8A from a different direction;
[0049] FIG. 10 is a perspective view of the femur, tibia, fibula, and
femoral pin guide
assembly of FIG. 88 with a femoral pin inserted through the femoral pin guide
assembly into
the distal femur;
[0050] FIG. 11 is a perspective view of the femur, tibia, fibula, femoral
pin guide assembly,
and femoral pin of FIG. 10 with a pin sleeve of the femoral pin guide assembly
removed;
[0051] FIG. 12 is a perspective view of the femur, tibia, fibula, and
femoral pin of FIG. 11
with the rest of the femoral pin guide assembly removed;
[0052] FIG. 13 is a perspective view of the femur, tibia, fibula, and
femoral pin of FIG. 12
with a tibial pin inserted into the tibial tuberosity;
[0053] FIG. 14A is a perspective view of the femur, tibia, fibula, femoral
pin, and tibial pin of
FIG. 13 and the foot holder assembly of FIG. 8A with a three in one cut guide
assembly coupled
to the femoral pin and distal femur, the tibial pin and tibia, and the foot
holder assembly via a
tibial extension rod assembly; and FIG. 1413 is a lateral view of the femur,
tibia, fibula, femoral
pin, tibial pin, foot holder assembly, three in one cut guide assembly, and
tibial extension rod
assembly of FIG. 14A;
[0054] FIG. 15A is a perspective view of the three in one cut guide
assembly and tibial
extension rod assembly of FIG. 14A; FIG. 1513 is an exploded perspective view
of the three in
one cut guide assembly of FIG. 15A; and FIG. 15C is another exploded
perspective view of the
three in one cut guide assembly of FIG. 15A from a different direction;
[0055] FIG. 16 is a perspective view of the femur, tibia, fibula, femoral
pin, tibial pin, three
in one cut guide assembly, and tibial extension rod assembly of FIG. 14A with
bone pins
inserted through the three in one cut guide assembly into the distal femur and
proximal tibia;
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[0056] FIG. 17 is a perspective view of the femur, tibia, fibula, femoral
pin, tibial pin, three
in one cut guide assembly, tibial extension rod assembly, and pins of FIG. 16
after making an
anterior femoral resection, a posterior femoral resection, and a proximal
tibial resection
through the three in one cut guide assembly;
[0057] FIG. 18 is a perspective view of the femur, tibia, fibula, femoral
pin, tibial pin,
anterior femoral resection, posterior femoral resection, and proximal tibial
resection of FIG. 17
with the three in one cut guide assembly and related bone pins removed;
[0058] FIG. 19 is a perspective view of the femur, tibia, fibula, femoral
pin, and tibial pin of
FIG. 18 and a portion of the femoral support arm assembly, collar, target
clamp assembly, and a
portion of the foot holder assembly of FIG. 8A with a distal femoral cut guide
assembly coupled
to the distal femur and the target clamp assembly via a femoral extension rod
assembly;
[0059] FIG. 20A is a perspective view of the distal femoral cut guide
assembly of FIG. 19;
FIG. 2013 is an exploded perspective view of the distal femoral cut guide
assembly of FIG. 19;
and FIG. 20C is another exploded perspective view of the distal femoral cut
guide assembly of
FIG. 19 from a different direction;
[0060] FIG. 21 is a perspective view of the femur, tibia, fibula, femoral
pin, tibial pin, distal
femoral cut guide assembly, and a portion of the femoral extension rod
assembly of FIG. 19
with bone pins inserted through the distal femoral cut guide assembly into the
distal femur;
[0061] FIG. 22 is a perspective view of the femur, tibia, fibula, tibial
pin, distal femoral cut
guide assembly, a portion of the femoral extension rod assembly, and related
bone pins of FIG.
21 after removing the femoral pin and making a distal femoral resection;
[0062] FIG. 23A is a perspective view of the femur, tibia, fibula, tibial
pin, distal femoral cut
guide assembly, a portion of the femoral extension rod assembly, and related
bone pins of FIG.
22 with a distal femoral cut block assembly of the distal femoral cut guide
assembly removed;
and FIG. 238 is a lateral view of the femur, distal femoral cut guide
assembly, a portion of the
femoral extension rod assembly, and related bone pins of FIG. 23A;
[0063] FIG. 24 is a perspective view of the femur, tibia, fibula, tibial
pin, distal femoral cut
guide assembly, a portion of the femoral extension rod assembly, and related
bone pins of FIG.
23A with a chamfer cut guide coupled to a femoral pin block of the distal
femoral cut guide
assembly;
[0064] FIG. 25 is a perspective view of the chamfer cut guide of FIG. 24;
[0065] FIG. 26 is a perspective view of the femur, tibia, fibula, tibial
pin, distal femoral cut
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guide assembly, a portion of the femoral extension rod assembly, related bone
pins, and
chamfer cut guide of FIG. 24 with bone pins inserted through the chamfer cut
guide into the
distal femur;
[0066] FIG. 27A is a perspective view of the femur, tibia, fibula, tibial
pin, distal femoral cut
guide assembly, a portion of the femoral extension rod assembly, related bone
pins, chamfer
cut guide, and related bone pins of FIG. 26 after making an anterior chamfer
cut and a posterior
chamfer cut; and FIG. 278 is a lateral view of the femur, tibia, fibula,
distal femoral cut guide
assembly, a portion of the femoral extension rod assembly, related bone pins,
chamfer cut
guide, and related bone pins of FIG. 27A with an implant trial coupled to the
chamfer cut guide;
[0067] FIG. 28A is a perspective view of the femur, tibia, fibula, femoral
pin, tibial pin, three
in one cut guide assembly, tibial extension rod assembly, and pins of FIG. 17
with a distal
femoral cut guide coupled to the distal anterior femur and the three in one
cut guide with bone
pins; FIG. 288 is a perspective view of the distal femoral cut guide of FIG.
28A; and FIG. 28C is a
side view of the distal femoral cut guide of FIG. 28A;
[0068] FIG. 29A is a perspective view of the femur, tibia, fibula, distal
femoral cut guide, and
pins of FIG. 28A after removing the femoral pin three in one cut guide
assembly and tibial
extension rod assembly and making a distal femoral resection; and FIG. 298 is
a lateral view of
the femur, tibia, fibula, distal femoral cut guide, and pins of FIG. 29A;
[0069] FIG. 30A is a perspective view of the femur, tibia, fibula, distal
femoral cut guide, and
pins of FIG. 29A with a chamfer cut guide coupled to the distal femur and the
distal femoral cut
guide with bone pins; and FIG. 3013 is a lateral view of the femur, tibia,
fibula, distal femoral cut
guide, pins, and chamfer cut guide of FIG. 30A;
[0070] FIG. 31A is a perspective view of the femur, tibia, fibula, chamfer
cut guide, and pins
of FIG. 30A after making anterior and posterior chamfer cuts; and FIG. 318 is
a lateral view of
the femur, tibia, fibula, chamfer cut guide, and pins of FIG. 31A;
[0071] FIG. 32 is a perspective view of the femur, tibia, and fibula with
the anterior, distal,
and posterior femoral resections, the anterior and posterior femoral chamfer
cuts, and the
proximal tibial resection with all instruments removed;
[0072] FIG. 33 is a perspective view of a femur, tibia, and fibula with a
foot receiver and a
lower bar of a foot holder assembly;
[0073] FIG. 34 is a perspective view of the femur, tibia, fibula, foot
receiver, and lower bar
of FIG. 33 with a femoral support arm assembly;
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[0074] FIG. 35A is a perspective view of the femur, tibia, fibula, foot
receiver, lower bar,
and femoral support arm assembly of FIG. 34 with a femoral head finder coupled
to the femoral
support arm assembly; and FIG. 358 is a top view of the femur, tibia, fibula,
foot receiver, lower
bar, femoral support arm assembly, and femoral head finder of FIG. 35A;
[0075] FIG. 36 is a perspective view of the femur, tibia, fibula, foot
receiver, lower bar,
femoral support arm assembly, and femoral head finder of FIG. 35A with a
collar coupled to the
femoral support arm assembly next to the femoral head finder;
[0076] FIG. 37 is a perspective view of the femur, tibia, fibula, foot
receiver, lower bar,
femoral support arm assembly, femoral head finder, and collar of FIG. 36 with
a target clamp
assembly coupled to the femoral support arm assembly next to the collar;
[0077] FIG. 38 is a perspective view of the femur, tibia, fibula, foot
receiver, lower bar,
femoral support arm assembly, collar, and target clamp assembly of FIG. 37
with a complete
foot holder assembly including a bridge, target mounting block, dovetail lock,
target, and
thumbscrew coupled to the lower bar and the foot receiver;
[0078] FIG. 39 is a perspective view of the femur, tibia, fibula, foot
holder assembly,
femoral support arm assembly, collar, and target clamp assembly of FIG. 38
after making a
provisional tibial resection;
[0079] FIG. 40A is a perspective view of the femur, tibia, fibula, foot
holder assembly,
femoral support arm assembly, collar, and target clamp assembly of FIG. 39
with a femoral pin
guide assembly coupled to the anterior distal femur and the target clamp
assembly via a
femoral extension rod assembly; and FIG. 4013 is a top view of the femur,
tibia, fibula, foot
holder assembly, femoral support arm assembly, collar, target clamp assembly,
femoral pin
guide assembly, and femoral extension rod assembly of FIG. 40A;
[0080] FIG. 41A is a perspective view of the femoral pin guide assembly of
FIG. 40A; and
FIG. 418 is another perspective view of the femoral pin guide assembly of FIG.
40A from a
different direction;
[0081] FIG. 42 is a perspective view of the femur, tibia, fibula, femoral
pin guide assembly,
and a portion of the femoral extension rod assembly of FIG. 40A with femoral
pins inserted
through the femoral pin guide assembly into the distal femur;
[0082] FIG. 43 is a perspective view of the femur, tibia, fibula, femoral
pin guide assembly,
and a portion of the femoral extension rod assembly of FIG. 40A with a pin
sleeve of the
femoral pin guide assembly and one of the femoral pins removed;
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[0083] FIG. 44 is a perspective view of the femur, tibia, fibula, and
remaining femoral pin of
FIG. 43 with the rest of the femoral pin guide assembly removed;
[0084] FIG. 45A is a perspective view of the femur, tibia, fibula, and
femoral pin of FIG. 44
and the foot holder assembly of FIG. 38 with a knee angle guide coupled to the
femoral pin; and
FIG. 458 is a lateral view of the femur, tibia, fibula, femoral pin, foot
holder assembly, and knee
angle guide of FIG. 45A;
[0085] FIG. 46 is a perspective view of the femur, tibia, fibula, and
femoral pin of FIG. 45A
with the knee angle guide removed, with a distal femoral cut guide assembly
coupled to the
femur and the femoral pin;
[0086] FIG. 47A is an exploded perspective view of the femoral pin and
distal femoral cut
guide assembly of FIG. 46; and FIG. 478 is another exploded perspective view
of the femoral pin
and distal femoral cut guide assembly of FIG. 46 from a different direction;
[0087] FIG. 48 is a perspective view of the femur, tibia, fibula, and a
portion of the distal
femoral cut guide assembly of FIG. 46 after making a distal femoral resection
and removing the
femoral pin and an interlock and a distal plate of the distal femoral cut
guide assembly;
[0088] FIG. 49A is a perspective view of the femur, tibia, and fibula of
FIG. 48 and the foot
holder assembly of FIG. 45A with a femoral four-in-one cut guide assembly
coupled to the distal
femur and a proximal tibial cut guide coupled to the proximal tibia and the
foot holder
assembly via a tibial extension rod assembly; FIG. 498 is an enlarged detail
view of the femur,
tibia, fibula, femoral four-in-one cut guide assembly, proximal tibial cut
guide, and a portion of
the tibial extension rod assembly of FIG. 49A; FIG. 49C is an anterior view of
the femur, tibia,
fibula, foot holder assembly, femoral four-in-one cut guide assembly, proximal
tibial cut guide,
and tibial extension rod assembly of FIG. 49A; and FIG. 49D is a lateral view
of the femur, tibia,
fibula, foot holder assembly, femoral four-in-one cut guide assembly, proximal
tibial cut guide,
and tibial extension rod assembly of FIG. 49A;
[0089] FIG. 50A is a perspective view of the femoral four-in-one cut guide
assembly and the
proximal tibial cut guide of FIG. 49A; FIG. 5013 is another perspective view
of the femoral four-
in-one cut guide assembly and the proximal tibial cut guide of FIG. 49A from a
different
direction; FIG. 50C is an exploded perspective view of the femoral four-in-one
cut guide
assembly and the proximal tibial cut guide of FIG. 49A; and FIG. 50D is
another exploded
perspective view of the femoral four-in-one cut guide assembly and the
proximal tibial cut
guide of FIG. 49A from a different direction;
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[0090] FIG. 51A is a front view of the femoral four in one cut guide
assembly of FIG. 50A;
FIG. 51B is a cross sectional view of the femoral four in one cut guide
assembly of FIG. 51A,
taken along section line 51B-51B of FIG. 51A; FIG. 51C is a cross sectional
view of the femoral
four in one cut guide assembly of FIG. 51A, taken along section line 51C-51C
of FIG. 51A; FIG.
51D is an exploded perspective view of the femoral four-in-one cut guide
assembly of FIG. 51A;
and FIG. 51E is another exploded perspective view of the femoral four-in-one
cut guide
assembly of FIG. 51A from a different direction;
[0091] FIG. 52A is an exploded perspective view of a gear assembly of the
femoral four in
one cut guide assembly of FIG. 51A; and FIG. 52B is another exploded
perspective view of the
gear assembly of the femoral four in one cut guide assembly of FIG. 51A from a
different
direction;
[0092] FIG. 53A is a perspective view of the femur, tibia, fibula, foot
holder assembly,
femoral four-in-one cut guide assembly, proximal tibial cut guide, and tibial
extension rod
assembly of FIG. 49A with the femoral four-in-one cut guide assembly and
proximal tibial cut
guide adjusted to fit the femur and tibia, with bone pins inserted through the
femoral four-in-
one cut guide assembly into the femur, with bone pins inserted through the
proximal tibial cut
guide into the tibia; FIG. 53B is an enlarged detail view of the femur, tibia,
fibula, foot holder
assembly, femoral four-in-one cut guide assembly, proximal tibial cut guide,
tibial extension rod
assembly, and bone pins of FIG. 53A; FIG. 53C is an enlarged anterior detail
view of the femur,
tibia, fibula, foot holder assembly, femoral four-in-one cut guide assembly,
proximal tibial cut
guide, tibial extension rod assembly, and bone pins of FIG. 53A; and FIG. 53D
is an enlarged
lateral detail view of the femur, tibia, fibula, foot holder assembly, femoral
four-in-one cut
guide assembly, proximal tibial cut guide, tibial extension rod assembly, and
bone pins of FIG.
53A;
[0093] FIG. 54 is a perspective view of the femur, tibia, fibula, femoral
four-in-one cut guide
assembly, proximal tibial cut guide, a portion of the tibial extension rod
assembly, and bone
pins of FIG. 53A after making anterior and posterior femoral resections,
anterior and posterior
chamfer cuts, and a proximal tibial resection;
[0094] FIG. 55 is a perspective view of the femur, tibia, and fibula with
the anterior, distal,
and posterior femoral resections, the anterior and posterior femoral chamfer
cuts, and the
proximal tibial resection with the femoral four-in-one cut guide assembly,
proximal tibial cut
guide, tibial extension rod assembly, and bone pins removed;
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[0095] FIG. 56 is an isometric view of a knee joint with implanted femoral
component, tibial
component, articular insert, and patellar component, the patellar component
shown exploded
from the patella for clarity;
[0096] FIG. 57 is a perspective view of a femur, tibia, and fibula with
another femoral pin
guide assembly and another distal femoral cut guide coupled to the distal
femur; and
[0097] FIG. 58A is an exploded perspective view of the femoral pin guide
assembly and
distal femoral cut guide of FIG. 57; and FIG. 58B is another exploded
perspective view of the
femoral pin guide assembly and distal femoral cut guide of FIG. 57 from a
different direction.
DETAILED DESCRIPTION
[0098] Exemplary embodiments of the technology will be best understood by
reference to
the drawings, wherein like parts are designated by like numerals throughout.
It will be readily
understood that the components of the system, as generally described and
illustrated in the
figures herein, could be arranged and designed in a wide variety of different
configurations.
Thus, the following more detailed description of the embodiments of the
apparatus, system,
and method is not intended to limit the scope of the invention, as claimed in
this or any other
application claiming priority to this application, but is merely
representative of exemplary
embodiments of the technology.
[0099] The phrases "connected to," "coupled to" and "in communication with"
refer to any
form of interaction between two or more entities, including mechanical,
electrical, magnetic,
electromagnetic, fluid, and thermal interaction. Two components may be
functionally coupled
to each other even though they are not in direct contact with each other. The
term "abutting"
refers to items that are in direct physical contact with each other, although
the items may not
necessarily be attached together. The phrase "fluid communication" refers to
two features that
are connected such that a fluid within one feature is able to pass into the
other feature.
[00100] The word "exemplary" is used herein to mean "serving as an example,
instance, or
illustration." Any embodiment described herein as "exemplary" is not
necessarily to be
construed as preferred or advantageous over other embodiments. While the
various aspects of
the embodiments are presented in drawings, the drawings are not necessarily
drawn to scale
unless specifically indicated.
[00101] Standard medical planes of reference and descriptive terminology
are employed in
this specification. A sagittal plane divides a body into right and left
portions. A mid-sagittal
plane divides the body into bilaterally symmetric right and left halves. A
coronal plane divides a
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body into anterior and posterior portions. A transverse plane divides a body
into superior and
inferior portions. Anterior means toward the front of the body. Posterior
means toward the
back of the body. Superior means toward the head. Inferior means toward the
feet. Medial
means toward the nnidline of the body. Lateral means away from the nnidline of
the body. Axial
means toward a central axis of the body. Abaxial means away from a central
axis of the body.
I psilateral means on the same side of the body. Contralateral means on the
opposite side of the
body. These descriptive terms may be applied to an animate or inanimate body.
[00102] Standard terminology related to knee arthroplasty is employed in
this specification.
Varus means deviation of the distal part of the leg below the knee inward,
resulting in a
bowlegged appearance. Valgus means deviation of the distal part of the leg
below the knee
outward, resulting in a knock-kneed appearance.
[00103] FIGS. 1-32 illustrate an instrument system 1500.
[00104] FIG. 1 shows the step of securing a foot (not shown, the lower leg
is represented by
the tibia 104 and fibula 122) in a portion of a foot holder assembly 1870. The
foot holder
assembly 1870 includes a foot receiver 1872, a lower bar 1874, a bridge 1878,
a target
mounting block 1880, a dovetail lock 1881, a target 1882, and a thumbscrew
1884. The bridge
1878, target mounting block 1880, dovetail lock 1881, target 1882, and
thumbscrew 1884 are
shown in FIGS. 6-7C.
[00105] FIG. 2 shows the step of securing a femoral support arm assembly
1786 to an
operating table (not shown) so that a portion of the femoral support arm
assembly extends
over the hip area. This step may be similar to or identical to the step of
FIG. 69 of U.S. Patent
Application No. 15/081828. The femoral support arm assembly 1786 includes a
post 1788, a bar
1790, a first clamp body 1792, a second clamp body 1794, a spring 1796, a
retaining ring 1798,
a thumbscrew 1800, and a screw 1802. The femoral support arm assembly 1786 may
be similar
to or identical to the femoral support arm assembly 786 or 2786.
[00106] FIG. 3 shows the step of positioning a femoral head finder 1918 to
extend over the
center 120 of the head 118 of the femur 100. This alignment may be verified
using imaging, for
example fluoroscopy. 70. The femoral head finder 1918 may be similar to or
identical to the
femoral head finder 918 or 2918.
[00107] FIG. 4 shows the step of securing a collar 1926 to the bar 1790
beside the femoral
head finder 1918. The steps of FIGS. 3 and 4 may be similar to or identical to
the step of FIG. 70
of U.S. Patent Application No. 15/081828. The collar 1926 may be similar to or
identical to the
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collar 926 or 2926. Preferably, the steps of FIGS. 1-4 may occur before
sterile draping of the
patient.
[00108] FIG. 5 shows the step of removing the femoral head finder 1918 and
securing a
target clamp assembly 1818 to the bar 1790 beside the collar 1926. This step
may be similar to
or identical to the step of FIG. 71 of U.S. Patent Application No. 15/081828.
Preferably, this step
may occur after the femoral support arm assembly 1786 has been covered with a
sterile drape,
such as drape 902 of FIG. 71 of U.S. Patent Application No. 15/081828. Thus
the collar 1926 and
the femoral support arm assembly 1786 may be nonsterile under the drape, and
the target
clamp assembly 1818 may be sterile above the drape. The target clamp assembly
1818 includes
a target 1820, a retaining ring 1822, a first clamp body 1824, a second clamp
body 1826, a lever
1828, a link 1830, and a pin 1832. The example shows two links 1830 and eight
pins 1832. The
target clamp assembly 1818 may be similar to or identical to the target clamp
assembly 818 or
2818.
[00109] FIG. 6 shows the step of assembling the bridge 1878, target
mounting block 1880,
dovetail lock 1881, target 1882, and thumbscrew 1884 to the lower bar 1874 and
the foot
receiver 1872 to form a complete foot holder assembly 1870. FIGS. 7A-7C show
the foot holder
assembly 1870.
[00110] The lower bar 1874 includes bilateral sockets 1000, 1002 on either
side of a concave
portion 1004. The lower bar 1874 may be similar to or identical to the lower
bar 874 or 2874.
The bridge 1878 is a horseshoe-shaped or U-shaped part with a central bridge
1006 and two
legs 1008, 1010, each leg extending from an end of the bridge 1006 and
terminating in a free
end. The free ends have tabs 1012, 1014, respectively. Each tab bifurcates at
its tip to form a
resilient snap feature. The bridge 1006 includes a through slot 1016 that
extends between back
to back pockets 1018, 1020. The target 1882 is a generally spoon-shaped or
ladle-shaped part
with an elongated stem 1022 that terminates in a bowl 1024 at one end. The
stem 1022
includes an undercut rail 1026 that extends along the length of the stem. The
target mounting
block 1880 has a generally rectangular or square body with a rectangular or
square through
hole 1028. An undercut channel 1030 extends across one side of the target
mounting block
1880 and across the hole 1028. The opposite side of the target mounting block
1880 includes
bilateral shelves or ledges 1032, 1034 that extend transverse to, or
perpendicular to, the
undercut channel 1030. The dovetail lock 1881 is an elongated part that
includes a generally
rectangular or square body 1036 with a threaded shaft 1038 extending from one
side of the
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body. Bilateral shelves or ledges 1038, 1040 extend across this side of the
body on opposite
sides of the shaft 1038. Opposite the shaft 1038, an undercut channel 1044
extends across the
body 1036 transverse to, or perpendicular to, the bilateral ledges 1038, 1040.
The thumbscrew
1884 includes a mushroom-shaped body 1046 with a threaded socket 1048 opposite
the
enlarged mushroom "cap." The foot receiver 1872 may be similar to or identical
to the foot
holder 872 or the foot receiver 2872.
[00111] The tab 1012 is received in the socket 1000 and the tab 1014 is
received in the
socket 1002. The tabs 1012, 1014 may snap into and out of engagement with the
sockets 1000,
1002. The target mounting block 1880 is at least partially received in the
pocket 1018 or 1020
so that the ledges 1032, 1034 rest atop the pocket walls. The target mounting
block 1880 is
shown in the pocket 1018. The body 1036 of the dovetail lock 1881 is at least
partially received
in the hole 1028 in the target mounting block 1880 so that the undercut
channels 1030, 1044
face the same direction and are aligned, and so that the shaft 1038 extends
through the slot
1016 of the bridge 1878 and threads into the socket 1048 of the thumbscrew
1884. The
thumbscrew 1884 is partially received in the pocket 1018 or 1020, whichever
one is not
occupied by the target mounting block 1880. The thumbscrew 1884 is shown in
the pocket
1020. The undercut rail 1026 of the target 1882 is received in the undercut
channels 1030,
1044. Tightening the thumbscrew 1884 locks the undercut rail 1026 in position
relative to the
bridge 1878. Loosening the thumbscrew 1884 permits the target 1882 to be moved
relative to
the bridge 1878 in the anterior to posterior direction and in the medial to
lateral direction.
[00112] FIGS. 8A and 8B show the step of coupling a femoral pin guide
assembly 1501 to the
anterior distal femur. This step may be similar to or identical to the step of
FIG. 72 of U.S.
Patent Application No. 15/081828. This step may include coupling the femoral
pin guide
assembly 1501 to the target 1820 of the target clamp assembly 1818 via a
femoral extension
rod assembly 1506 (FIG. 19). This step may include aligning the femoral pin
guide assembly
1501 and/or the femoral extension rod assembly 1506 with the mechanical axis
202 of the leg
as it extends through the femur 100. FIGS. 9A-9C show the femoral pin guide
assembly 1501,
which includes a base 1502, a handle 1516, a pin guide 1521, a screw 1513, and
a pin sleeve
1515. The example shows two screws 1513. Aligning the femoral pin guide
assembly 1501
and/or the femoral extension rod assembly 1506 with the mechanical axis 202 of
the leg may
include centering the base 1502 in the medial-lateral width of the distal
femur and at the same
time aligning the femoral extension rod assembly 1506 to pass over the center
120 of the
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femoral head 118. This step may include positioning a distal edge of the bone
contacting
surface 1518 at the place on the distal anterior femur where the anterior
femoral resection 214
is planned to exit the femur.
[00113] The base 1502 is an elongated plate with a bone contacting surface
1518 and an
opposite top surface 1520. The base 1502 has a distal portion 1522 and a
proximal portion 1524
which tapers to a proximal tip which is narrower than the distal portion. A
longitudinal axis
1503 extends along the length of the base 1502 between the distal and proximal
portions 1522,
1524; only a portion of the axis 1503 is shown for clarity. The base 1502
includes a hole 1526
through the distal portion 1522. A pocket 1528 is recessed into the bone
contacting surface
1518 around the hole 1526. The pocket 1528 may be described as a counterbore
around the
hole 1526. The base 302 includes two through holes 1530, 1532 between the
distal and
proximal portions 1522, 1524. Each hole 1530, 1532, 1534 includes a shelf 1536
on at least one
side wall. The shelves 1536 are illustrated as counterbores around the holes
1530, 1532, 1534
but may be unilaterally positioned instead. The base 1502 may include one or
more frictional
elements, such as spikes 1538 protruding from the bone contacting surface
1518. The spikes
1538 in this example are separate set screws with sharp leading tips inserted
into
corresponding holes 1539 in the base 1502.
[00114] The handle 1516 includes a base portion 1561 with a bone facing
surface 1562 and
an opposite top side 1564. The base portion 1561 has a distal portion 1566 and
a proximal
portion 1568. The base portion 1561 has a series of holes 1571, 1573, 1575,
1577 arranged
from distal to proximal. An optional tab 1579 may extend from the top side
between holes
1571, 1573. A stalk 1570 protrudes from the top side 1564 between the distal
and proximal
portions 1566, 1568. The stalk 1570 terminates in a proximal free end 1581
with a slot 1583
and through hole 1585.
[00115] The pin guide 1521 has a generally arcuate body 1523 that extends
between a distal
portion 1525 and a proximal portion 1527. The distal portion 1525 includes a
longitudinal hole
1529 with a longitudinal slot 1531. The hole 1529 and slot 1531 extend in the
distal-proximal
direction. The proximal portion 1527 includes a pocket 1533 and holes 1535,
1537 which
intersect the pocket. The pin sleeve 1515 includes a cylindrical shaft 1541
with an enlarged
head 1543 at one end and a longitudinal through hole 1545.
[00116] The shaft 1541 of the pin sleeve 1515 is received in the hole 1529
of the pin guide
1521 so that the head 1543 is distal. The distal portion 1566 of the handle
1516 is received in
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the pocket 1533 of the pin guide 1521. One of the screws 1513 extends through
the holes 1535,
1571 and the other screw 1513 extends through the holes 1537, 1573 to secure
the pin guide
1521 to the handle 1516. The spikes 1538 are received in the holes 1539; the
spikes may
optionally be integrally formed with the base 1502. A fastener (not shown)
extends through the
holes 1526, 1575 and a second fastener extends through the holes 1530, 1577
(for a left knee)
or the holes 1532, 1577 (for a right knee) to secure the base 1502 to the
handle. When the pin
sleeve 1515, pin guide 1521, handle 1516, and base 1502 are coupled together
as described,
the hole 1545 may be aligned with the bone contacting surface 1518, or a
theoretical bone
contacting plane defined by the spikes 1538 where the spikes contact the
distal anterior femur.
Preferably, the hole 1545 may be parallel to the bone contacting surface 1518,
parallel to the
upcoming anterior femoral resection 214, or perpendicular to the upcoming
distal femoral
resection 206. The inner rod 1606 of the femoral extension rod assembly 1506
is received in the
slot 1583 and the pin 1601 extends through hole 1585 and the inner rod to form
a hinge about
which the femoral extension rod assembly pivots in use.
[00117] FIG. 10 shows the step of placing a femoral pin 1505 into the
distal femur through
the pin sleeve 1515 of the femoral pin guide assembly 1501. The femoral pin
1505 is received in
the hole 1545. Preferably, this step occurs while the bone contacting surface
1518 and/or the
spikes 1538 of the base 1502 contact the distal anterior femur, and while the
femoral pin guide
assembly 1501 and/or the femoral extension rod assembly 1506 are aligned with
the
mechanical axis 202 of the leg. Preferably, the femoral pin 1505 is placed in
strong, dense
subtrochlear bone anterior to the femoral intrannedullary canal and posterior
to the intended
location of the upcoming anterior femoral resection 214.
[00118] FIG. 11 shows the step of removing the pin sleeve 1515 after the
femoral pin 1505
has been placed into the distal femur. The pin sleeve 1515 slides distally out
of the hole 1529
and distally along the femoral pin 1505. This exposes the slot 1531.
[00119] FIG. 12 shows the step of removing the femoral pin guide assembly
1501 after the
femoral pin 1505 has been placed into the distal femur. The femoral pin guide
assembly 1501
may be lifted anteriorly so that the femoral pin 1505 exits through the slot
1531. This step may
include removing the spool 1608 anteriorly from the target 1820. The femoral
pin 1505
encodes information about 1) the proper varus/valgus orientation of the distal
femoral
resection 206, 2) the flexion/extension orientation of the anterior femoral
resection 214 and
the posterior femoral resection 220, and 3) the middle of the trochlear groove
(Whiteside's
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line). The femoral pin 1505 enables rotational adjustment of cut guides about
the pin 1505,
which ensures proper tracking of the patella. More specifically, femoral cut
guides may be
adjusted for varus-valgus rotation about the pin 1505.
[00120] FIG. 13 shows the step of placing a tibial centering pin 1507 in
the tibial tuberosity to
serve as a proximal tibial target. The tibial centering pin 1507 may be placed
freehand or with a
guide (not shown). The tibial centering pin 1507 may be centered in the medial-
lateral width of
the proximal tibia 106 and/or centered in the medial-lateral width of the
tibial tuberosity.
[00121] FIGS. 14A and 1413 show the step of coupling a three in one cut
guide assembly 1321
to the femur 100, the tibia 104, and the foot holder assembly 1870. This step
may include
sliding a hole of the three in one cut guide assembly 1321 over the femoral
pin 1505. This step
may include sliding a slot of the three in one cut guide assembly 1321 over
the tibial pin 1507.
The three in one cut guide assembly 1321 may pivot around the femoral pin 1505
to a
rotational position in which the slot accepts the tibial pin 1507. This step
may include coupling
the three in one cut guide assembly 1321 to a tibial extension rod assembly
1511, and coupling
the tibial extension rod assembly to a target 1882 of the foot holder assembly
1870. This step
may include aligning the three in one cut guide assembly 1321 and/or the
tibial extension rod
assembly 1511 with the mechanical axis of the leg as it extends through the
tibia 104. The three
in one cut guide assembly 1321 shown in FIGS. 15A-15C includes an anterior
femoral cut guide
1326, a posterior femoral and tibial cut guide 1328, a tibial rail 1323, and a
button assembly
1327. The three in one cut guide assembly 1321 is coupled to a tibial
extension rod assembly
1511, which is coupled to the foot holder assembly 1870. FIG. 1413 shows that
it is preferable
for the tibia 104 to be positioned so that a tibial shaft axis 201 forms a
ninety degree angle
1315 with the femoral shaft axis 200 of the femur 100. The anterior femoral
cut guide 1326 and
the posterior femoral and tibial cut guide 1328 are pinned to the distal femur
and proximal
tibia, respectively, with femoral pin 1505 and tibial pin 1507. The example
shows two tibial rails
1323 and two button assemblies 1327. The button assembly 1327 includes a
button, a spring,
and a dowel pin. The tibial extension rod assembly 1511 (FIG. 19) includes an
outer rod 1605,
an inner rod 1607, a sleeve 1611, a ring 1613, a pin 1601, and a ball 1617.
The tibial extension
rod assembly 1511 may be similar to or identical to the tibial extension rod
313, 511, 2511 or
the femoral extension rod 306, 506, 1506, 2506. Aligning the three in one cut
guide assembly
1321 and/or the tibial extension rod assembly 1511 with the mechanical axis of
the leg may
include centering the posterior femoral and tibial cut guide 1328 over the
tibial pin 1507 and at
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the same time aligning the tibial extension rod assembly 1511 to pass over the
medial-lateral
center of the ankle, the second toe, or anterior tibial spine.
[00122] The anterior femoral cut guide 1326 has a distal side 1050, an
opposite proximal side
1052, and an anterior side 1054. A saw slot 1056 extends through the anterior
femoral cut
guide 1326 in a distal to proximal direction. A boss 1058 extends from a
middle portion of the
distal side 1050. A through hole 1060 extends through the boss 1058. The
through hole 1060
receives the femoral pin 1505, thereby positioning the saw slot 1056 so that
the anterior
femoral resection 214 will exit the femur at the planned location. Bilateral
through holes 1062,
1064 are located on either side of the boss 1058. The holes 1062, 1064 may
include
counterbores 1066, 1068 as shown in the distal side 1050. The holes 1062, 1064
may converge
as they extend from distal to proximal. Bilateral rectangular or square
through holes 1070, 1072
are located on either side of the boss 1058; the holes 1070, 1072 are shown
outboard of the
holes 1062, 1064, but could be inboard instead. The holes 1070, 1072 extend
through the
anterior femoral cut guide 1326 in an anterior to posterior direction passing
through the
anterior side 1054.
[00123] The posterior femoral and tibial cut guide 1328 has a distal side
1074, an opposite
proximal side 1076, and an anterior side 1078. Saw slots 1080, 1082 extend
through the
posterior femoral and tibial cut guide 1328 in a distal to proximal direction.
The saw slots 1080,
1082 may be parallel or there may be an acute angle between them. An arm 1084
extends
distally and posteriorly from a middle portion of the distal side 1074. The
free end 1085 of the
arm 1084 includes a lengthwise slot 1086 and a hole 1088 that extends through
the arm and
across the slot. Bilateral through holes 1090, 1092 are located on either side
of the arm 1084.
The holes 1090, 1092 may include counterbores 1094, 1096 as shown in the
distal side 1074.
The holes 1062, 1064 may converge as they extend from distal to proximal.
Bilateral
rectangular or square bosses 1100, 1102 extend from the distal side 1074 on
either side of the
arm 1084. The bosses 1100, 1102 are shown outboard of the holes 1090, 1092,
but could be
inboard instead. Rectangular or square pockets 1104, 1106 are recessed into
the distal aspect
of the bosses 1100, 1102. Circular holes 1108, 1110 are recessed into the
proximal ends of the
pockets 1104, 1106. Rectangular or square through holes 1112, 1114 extend
through the
bosses 1100, 1102 in a distal to proximal direction. An anterior facing shelf
1116 is formed
between anterior and posterior portions of the posterior femoral and tibial
cut guide 1328.
Bilateral rectangular or square through holes 1118, 1120 are located on either
side of the boss
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arm; the holes 1118, 1120 are shown outboard of the holes 1090, 1092, but
could be inboard
instead. The holes 1118, 1120 extend through the posterior femoral and tibial
cut guide 1328 in
an anterior to posterior direction passing through the anterior side 1078.
Posterior facing
shelves 1122, 1124 are formed in the proximal side of the posterior femoral
and tibial cut guide
1328. The shelf 1122 rests on the proximal aspect of the tibia when the three
in one cut guide
1321 is adjusted to an implant size that matches the patient's anatomy.
[00124] The tibial rail 1323 is a generally rectangular elongated part with
an anterior end
1126, a posterior end 1128, and a proximal side 1130. A series of detents
1132, in this example
grooves, extends along a middle portion of the proximal side 1130. Indicia
1134 may be present
on the tibial rail 1323.
[00125] The button assembly 1327 includes a button body 1136, a spring 1138,
and a pin
1140. The button body 1136 includes a generally rectangular shaft 1142 with an
enlarged head
1144 at one end. A generally rectangular through hole 1146 extends
transversely through the
shaft 1142. A through hole 1148 extends transversely through the shaft 1142
and across the
hole 1146.
[00126] The anterior ends 1126 of the tibial rails 1323 are received in the
holes 1070, 1072
of the anterior femoral cut guide 1326 so that the posterior ends 1128 project
posteriorly and
the proximal sides 1052, 1130 face the same direction. The anterior ends 1126
may be fixed in
the holes 1070, 1072. A spring 1138 is received in each hole 1146 of the
button bodies 1136.
The button bodies 1136 are received in the posterior femoral and tibial cut
guide 1328 so that
the shafts 1142 are in the holes 1112, 1114, the springs 1138 are in the holes
1108, 1110, the
heads 1144 are in the pockets 1104, 1106, and the holes 1148 are exposed
proximally to
receive the pins 1140. The posterior ends 1128 of the tibial rails 1323, with
attached anterior
femoral cut guide 1326, are received in the anterior ends of the holes 1118,
1120 of the
posterior femoral and tibial cut guide 1328 and advanced through the holes
1146 of the button
bodies 1136 so that the springs 1138 are distal to the tibial rails 1323 and
the pins 1140 engage
the detents 1132. The inner rod 1607 of the tibial extension rod assembly 1511
is received in
the slot 1086 and the pin 1601 extends through hole 1088 and the inner rod to
form a hinge
about which the tibial extension rod assembly pivots in use.
[00127] FIG. 16 shows the step of further securing the three in one cut
guide assembly 1321
to the femur 100 and the tibia 104 by driving bone pins 1329 through the
anterior femoral cut
guide 1326 and the posterior femoral and tibial cut guide 1328. Preferably,
this step occurs
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while the three in one cut guide assembly 1321 and/or the tibial extension rod
assembly 1511
are aligned with the mechanical axis 202 of the leg.
[00128] FIG. 17 shows the step of making an anterior femoral resection 214,
a posterior
femoral resection 220, and a proximal tibial resection 210. The anterior
femoral resection 214 is
made through the saw slot 1056 in the anterior femoral cut guide 1326, which
is carried on the
femoral pin 1505, which was positioned in the distal femur while directly
referencing the distal
anterior femoral cortex, notably the desired exit point for the anterior
femoral resection 214.
The posterior femoral resection 220 is made through the femoral saw slot 1080
in the posterior
femoral and tibial cut guide 1328. The proximal tibial resection 210 is made
through the tibial
saw slot 1082 in the posterior femoral and tibial cut guide 1328. Note that
the proximal tibial
resection 210 is made while the soft tissues surrounding the knee joint are
intact and loaded by
the natural anatomy. Thus the conventional step of balancing soft tissues may
be greatly
reduced or eliminated altogether.
[00129] FIG. 18 shows the step of removing the three in one cut guide
assembly 1321 after
making the anterior femoral resection 214, the posterior femoral resection
220, and the
proximal tibial resection 210.
[00130] FIG. 19 shows the step of coupling a distal femoral cut guide
assembly 1519 to the
femur 100. This step may include coupling the distal femoral cut guide
assembly 1519 to the
anterior distal femur and the target 1820 of the target clamp assembly 1818
via the femoral
extension rod assembly 1506. This step may include aligning the distal femoral
cut guide
assembly 1519 and/or the femoral extension rod assembly 1506 with the
mechanical axis 202
of the leg as it extends through the femur 100. The distal femoral cut guide
assembly 1519
shown in FIGS. 20A-20C includes a femoral pin block 1514, a femoral riser
1504, a screw 1150, a
pin 1152, and a distal femoral cut block assembly 1638. The distal femoral cut
guide assembly
1519 is coupled to a femoral extension rod assembly 1506. The femoral
extension rod assembly
1506 includes an outer rod 1604, an inner rod 1606, a spool 1608, a sleeve
1610, a ring 1612, a
retaining ring 1614, and the pin 1601. The femoral extension rod assembly 1506
may be similar
to or identical to the femoral extension rod 306, 506, 2506 or the tibial
extension rod 313, 511,
1511, 2511. The distal femoral cut block assembly 1638 shown in FIGS. 20A-20C
includes a
distal femoral cut block 1637 and two pegs 1646. Aligning the distal femoral
cut guide assembly
1519 and/or the femoral extension rod assembly 1506 with the mechanical axis
202 of the leg
may include centering the femoral pin block 1514 in the medial-lateral width
of the distal femur
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and at the same time aligning the femoral extension rod assembly 1506 to pass
over the center
120 of the femoral head 118. This step may reference four anatomical reference
points: the
distal margin of the medial femoral condyle, the femoral pin 1505 (which was
placed by
referencing the distal anterior femoral cortex and the mechanical axis of the
leg), the anterior
femoral resection 214, and the mechanical axis 202 of the leg (directly).
[00131] The femoral pin block 1514 is a roughly triangular plate with a
bone facing surface
1154 and an opposite top surface 1156. The bone facing surface 1154 is
positioned against the
anterior femoral resection 214. The femoral pin block 1514 has a distal
portion 1566 and a
proximal portion 1568. The femoral pin block 1514 is illustrated with several
through holes
1162, 1164, 1166 which receive bone pins; two mounting holes 1168 are shown as
well. Two
proximal holes 1162 are shown, twelve middle holes 1164 are shown, and four
distal holes
1166 are shown, although any number of holes may be provided. The left and
right holes 1162
may converge together as they approach the bone facing surface 1154. The left
group and the
right group of holes 1164 may also converge together as they approach the bone
facing surface
1154. The left group and the right group of holes 1166 may include individual
holes that are
spaced apart widely enough in the medial-lateral direction that femoral
resections may be cut
while the femoral pin block 514 remains secured to the femur 100. These widely
spaced holes
1166 may be located outboard of the mounting holes 1168 so that bone pins
driven through
the widely spaced holes 1166 penetrate the epicondyles. The femoral pin block
1514 may be
widened as shown to support the widely spaced holes 1166. The femoral pin
block 514 includes
a blind hole 1170 and a through hole 1172. All of the preceding holes 1162,
1164, 1166, 1168,
1170, 1172 extend at least through the top surface 1154 of the femoral pin
block. The distal
portion 1566 includes a transverse undercut channel 1174 with a dimple 1176 in
its proximal
surface.
[00132] The femoral riser 1504 is a generally curved bar with a distal
portion 1178 and a
proximal portion 1180. Two holes 1182, 1184 extend anteriorly into the distal
portion 1178.
The proximal portion 1180 includes a longitudinal slot 1186 and a transverse
hole 1188 that
extends across the slot 1186.
[00133] The distal femoral cut block 1637 includes a proximal mounting
portion 1190 and a
distal paddle 1192. The mounting portion 1190 includes a bar 1194 with a peg
1646 extending
from each end of the bar. The pegs 1646 are parallel, and in this example they
are separate pins
which are coupled to holes 1196 in the bar 1194; the pegs 1646 may be integral
with the bar
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1194 instead. The bar 1194 includes a saw slot 1198 which extends in an
anterior-posterior
direction through the bar 1194. The paddle 1192 includes a proximal surface
1200 which is
positioned against the distal medial condyle. The saw slot 1198 is offset 9 mm
from the
proximal surface 1200 in the example shown.
[00134] The pin 1152 is received in the hole 1170 of the femoral pin block
1514 and the hole
1182 of the femoral riser 1504. The screw 1150 extends through the holes 1172,
1184 to secure
the femoral pin block 514 and the femoral riser 1504 together. The pegs 1646
are received in
the holes 1196 of the distal femoral cut block 1637, and may be press fit or
otherwise fixed in
place. The pegs are also received in the holes 1168 of the femoral pin block
514 to couple the
distal femoral cut block assembly 1638 to the femoral pin block.
[00135] FIG. 21 shows the step of further securing the distal femoral cut
guide assembly
1519 to the distal femur with bone pins 1329. Preferably, this step occurs
while the bone facing
surface 1154 of the femoral pin block 1514 contacts the anterior femoral
resection 214, and
while the femoral pin guide assembly 1501 and/or the femoral extension rod
assembly 1506
are aligned with the mechanical axis 202 of the leg. This improves the
accuracy of the distal
femoral resection 206.
[00136] FIG. 22 shows the step of removing the femoral pin 1505 and making
a distal
femoral resection 206. The distal femoral resection 206 is made through the
saw slot 1198 in
the distal femoral cut block 1637.
[00137] FIGS. 23A and 238 show the step of removing the distal femoral cut
block assembly
1638 and illustrate the adjustability provided by the distal femoral cut block
1637, an optional
insert 1202, and the femoral pin block 1514. The optional insert 1202 may be
included in the
distal femoral cut guide assembly 1519 to provide adjustability to the distal
femoral cut. A cut
made through the saw slot 1198 of the distal femoral cut block 1637 is in the
standard or zero
position. If the distal femoral cut block assembly 1638 is removed, a cut made
against the distal
surface 1208 of the insert 1202 is 2 mm proximal to the standard position. If
the insert 1202 is
removed, a cut made against the distal surface 1566 of the femoral pin block
1514 is 4 mm
proximal to the standard position. The insert 1202 is an elongated bar with a
longitudinal
proximal undercut rail 1204 and a retention tab 1206 on the rail.
[00138]
[00139] FIG. 24 shows the step of coupling a chamfer cut guide 1751 to the
femoral pin block
1514 in place of the distal femoral cut block assembly 1638. FIGS. 24-25 show
views of the
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chamfer cut guide 1751. The chamfer cut guide 1751 includes a generally
rectangular body
1210 with a distal surface 1212, an opposite proximal surface 1214, and an
anterior surface
1216. The chamfer cut guide 1751 has two saw slots 1218, 1220 which intersect
at the distal
surface 1212 and diverge anteriorly and posteriorly as they extend toward the
proximal surface
1214. Bilateral tabs 1222, 1242 extend from the chamfer cut guide 1751 on
either side of the
saw slots 1218, 1220. Bilateral through holes 1226, 1228 extend through the
tabs 1222, 1242,
respectively, in a distal to proximal direction. An L-shaped plate 1230
extends anteriorly and
proximally from the anterior surface 1216. The L-shaped plate 1230 includes an
anterior plate
1231 and a proximal plate 1234. The proximal plate 1234 includes a posterior
surface 1236. The
proximal surface 1214 is positioned against the distal femoral resection 206
and the posterior
surface 1236 is positioned against the top surface 1156 of the femoral pin
block 1514 so that
the tabs 1222, 1224 extend medially and laterally relative to the distal femur
100.
[00140] FIG. 26 shows the step of further securing the chamfer cut guide
1751 to the distal
femur with bone pins 1329. Preferably, this step occurs while the proximal
surface 1214 is in
close contact with the distal femoral resection 206 and the posterior surface
1236 is in close
contact with the top surface 1156.
[00141] FIG. 27A shows the step of making an anterior chamfer cut 216 and a
posterior
chamfer cut 218. The anterior chamfer cut 216 is made through the anterior saw
slot 1218 in
the chamfer cut guide 1751. The posterior chamfer cut 218 is made through the
posterior saw
slot 1220 in the chamfer cut guide 1751.
[00142] The chamfer cut guide 1751 may be removed so that the distal femoral
resection
206 may be adjusted as illustrated in FIG. 23B. The chamfer cut guide 1751 may
then be
repositioned so that the anterior and posterior chamfer cuts 216, 218 can also
be adjusted.
[00143] FIG. 27B shows an optional step of coupling an implant trial 1238
to the posterior
femoral resection 220 and the chamfer cut guide 1751 so that the knee may be
moved through
a range of motion to verify that the proper flexion/extension gaps have been
established.
Preferably, this step occurs while the chamfer cut guide 1751 and the distal
femoral cut block
assembly 1638 remain secured to the femur.
[00144] FIGS. 28A-31B illustrate a group of steps for making the distal
femoral resection 206
and the anterior and posterior chamfer cuts 216, 218 that may be performed as
an alternative
to the steps illustrated in FIGS. 18-27B.
[00145] FIG. 28A shows the step of coupling a distal femoral cut guide 1240
to the distal
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anterior femur 100 and the three in one cut guide assembly 1321 of FIG. 17
with bone pins
1329. An advantage of this step is that the original alignment to the
mechanical axis 202 of the
leg established in FIG. 8A is maintained via the femoral pin 1505, the tibial
pin 1507, the tibial
extension rod assembly 1511, and the target 1882. Referring to FIGS. 28B and
28C, the distal
femoral cut guide 1240 includes a distal surface 1242, a proximal surface
1244, an anterior
surface 1246, and a posterior surface 1262. A saw slot 1248 and one or more
holes 1250 extend
through the distal femoral cut guide 1240 in an anterior to posterior
direction. Five holes 1250,
1252, 1254, 1256, 1258 are shown. The holes may be counterbored at the
anterior surface
1246. A tab 1260 extends distally from the distal surface 1242. The posterior
surface 1262 is
positioned against the anterior femoral resection 214, the tab 1242 is
received in the saw slot
1056 of the anterior femoral cut guide 1326, and the distal surface 1242 is
positioned against
the proximal surface 1052.
[00146] FIG. 29A shows the step of removing the femoral pin 1505, three in
one cut guide
assembly 1321 and tibial extension rod assembly 1511 and making the distal
femoral resection
206 through the saw slot 1248 of the distal femoral cut guide 1240.
[00147] FIG. 30A shows the step of coupling a chamfer cut guide 1264 to the
distal femur
and the distal femoral cut guide 1240 with bone pins 1329. The chamfer cut
guide 1264
includes a distal surface 1266, a proximal surface 1268, and an anterior
surface 1270. The
chamfer cut guide 1264 has two saw slots 1272, 1274 which intersect at the
distal surface 1266
and diverge anteriorly and posteriorly as they extend toward the proximal
surface 1268.
Bilateral tabs 1276, 1278 extend from the chamfer cut guide 1264 on either
side of the saw
slots 1272, 1274. Bilateral through holes 1280, 1282 extend through the tabs
1276, 1278,
respectively, in a distal to proximal direction. A plate 1284 extends
anteriorly from the anterior
surface 1270. A slot 1286 extends through the plate 1284 in a distal to
proximal direction. The
proximal surface 1268 is positioned against the distal femoral resection 206,
the tab 1260 of
the distal femoral cut guide 1240 is received in the slot 1286 of the chamfer
cut guide 1264, and
the plate 1284 may be positioned against the distal surface 1242.
[00148] FIGS. 31A and 31B show the step of making anterior and posterior
chamfer cuts 216,
218. The anterior chamfer cut 216 is made through the saw slot 1272 of the
chamfer cut guide
1264 and the posterior chamfer cut 218 is made through the saw slot 1274.
[00149] FIG. 32 shows the femur 100, tibia 104, and fibula 122 after making
the anterior
femoral resection 214, the anterior chamfer cut 216, the distal femoral
resection 206, the
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posterior chamfer cut 218, the posterior femoral resection 220, and the
proximal tibial
resection 210, and after removing all instruments. FIG. 32 represents an
endpoint for the steps
shown in FIGS. 18-27B or for the steps shown in FIGS. 28A-31B.
[00150] FIGS. 33-58B illustrate another instrument system 2500.
[00151] FIG. 33 shows the step of securing a foot (not shown) in a portion
of a foot holder
assembly 2870. This step may be similar to or identical to the step of FIG. 1.
The foot holder
assembly 2870 includes a foot receiver 2872, a lower bar 2874, a bridge 2878,
a target
mounting block 2880, a dovetail lock 2881, a target 2882, and a thumbscrew
2884. The bridge
2878, target mounting block 2880, dovetail lock 2881, target 2882, and
thumbscrew 2884 are
shown in FIG. 38. The foot holder assembly 2870 may be similar to or identical
to the foot
holder assembly 870 or 1870.
[00152] FIG. 34 shows the step of securing a femoral support arm assembly
2786 to an
operating table (not shown) so that a portion of the femoral support arm
assembly extends
over the hip area. This step may be similar to or identical to the step of
FIG. 69 of U.S. Patent
Application No. 15/081828 and/or FIG. 2 of this application. The femoral
support arm assembly
2786 includes a post 2788, a bar 2790, a first clamp body 2792, a second clamp
body 2794, a
spring 2796, a retaining ring 2798, a thumbscrew 2800, and a screw 2802. The
femoral support
arm assembly 2786 may be similar to or identical to the femoral support arm
assembly 786 or
1786.
[00153] FIGS. 35A-35B show the step of positioning a femoral head finder
2918 to extend
over a center 120 of a head of the femur 100. This step may be similar to or
identical to the
step of FIG. 70 of U.S. Patent Application No. 15/081828 and/or FIG. 3 of this
application. FIG.
35A is a perspective view and FIG. 35B is a top view. The femoral head finder
2918 may be
similar to or identical to the femoral head finder 918 or 1918. Imaging, such
as radiographs,
fluoroscopy, a C-arm, and the like, may facilitate positioning the femoral
head finder 2918
accurately over the center 120 of the femoral head.
[00154] Alternatively, the center of the femoral head may be located using
ultrasound.
Ultrasound equipment may already be present in the operating room for
preoperative
identification of the femoral nerve or other neurovascular structures. The
inventors have
observed that the arcs of the femoral head and acetabulunn show up clearly on
ultrasound. The
arc of the femoral head or acetabulunn may be used to determine the location
of the center of
the femoral head. A skin mark may be made over the center of the femoral head.
The skin mark
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may be made with a pen, an adhesive sticker, a clip or skin staple, a skin-
piercing stud, or the
like. A skin-pinching or skin-penetrating mark may be preferable in the
presence of ultrasound
gel. The skin mark may be transferred to the femoral support arm assembly 2786
with a plumb
line, which may be supported by the femoral head finder 2918 on the bar 2790.
Line 119 in FIG.
35A indicates the plumb line supported by the femoral head finder 2918 and
positioned over
the skin mark over the center 120 of the femoral head.
[00155] FIG. 36 shows the step of securing a collar 2926 to the bar 2790
beside the femoral
head finder 2918. This step may be similar to or identical to the step of FIG.
70 of U.S. Patent
Application No. 15/081828 and/or FIG. 4 of this application. The collar 2926
may be similar to
or identical to the collar 926 or 1926.
[00156] The preceding steps may be performed before the patient is sterile
draped. This is
advantageous as it occurs before operative time begins to toll.
[00157] FIG. 37 shows the step of removing the femoral head finder 2918 and
securing a
target clamp assembly 2818 to the bar 2790 beside the collar 2926. This step
may be similar to
or identical to the step of FIG. 71 of U.S. Patent Application No. 15/081828
and/or FIG. 5 of this
application. The target clamp assembly 2818 includes a target 2820, a
retaining ring 2822, a
first clamp body 2824, a second clamp body 2826, a lever 2828, a link 2830,
and a pin 2832. The
example shows two links 2830 and eight pins 2832. The target clamp assembly
2818 may be
similar to or identical to the target clamp assembly 818 or 1818. The femoral
support arm
assembly 2786 with attached collar 2926 may be covered by a sterile drape
after the femoral
head finder 2918 is removed and before the target clamp assembly 2818 is
coupled to the bar
2790, in a manner similar to that shown in FIG. 71 of U.S. Patent Application
No. 15/081828.
[00158] FIG. 38 shows the step of assembling the bridge 2878, target
mounting block 2880,
dovetail lock 2881, target 2882, and thumbscrew 2884 to the lower bar 2874 and
the foot
receiver 2872 to form a complete foot holder assembly 2870. This step may be
similar to or
identical to the step of FIG. 6.
[00159] FIG. 39 shows the step of making a small provisional proximal
tibial resection 209 at
the base of the tibial eminence at the level of the normal lateral tibial
plateau, which may
optionally be referred to as a tibial sizing notch in situations where the
resection 209 is limited
to a small area such as the center of the lateral articular surface. The
provisional proximal tibial
resection 209 may involve the anterior portion of the tibial plateau as shown,
or it may be less
extensive or more extensive than shown. For example, the provisional proximal
tibial resection
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209 may involve only the tibial eminence. The provisional proximal tibial
resection 209 marks
the level of the unworn lateral tibial plateau and the actual joint line of
the femoral-tibial joint.
[00160] FIGS. 40A-40B show the step of coupling a femoral pin block
assembly 2501 to the
anterior distal femur. This step may be similar to or identical to the step of
FIG. 72 of U.S.
Patent Application No. 15/081828 and/or FIG. 8A of this application. FIG. 40A
is a perspective
view and FIG. 40B is a top view. The femoral pin block assembly 2501 includes
a base 2502, a
handle 2516, a pin guide 2514, a screw 2513, and a pin sleeve 2515. The
example shows two
screws 2513. The femoral pin block assembly 2501 is coupled to a femoral
extension rod
assembly 2506. The femoral extension rod assembly 2506 includes an outer rod
2604, an inner
rod 2606, a spool 2608, a sleeve 2610, a ring 2612, a retaining ring 2614, and
a pin 2601. The
femoral extension rod assembly 2506 may be similar to or identical to the
femoral extension
rod 306, 506, 1506 or the tibial extension rod 313, 511, 1511, 2511. The spool
2608 rests in the
target 2820 so that the femoral extension rod assembly 2506 extends over the
center 120 of
the femoral head.
[00161] FIGS. 41A-41B show perspective views of the femoral pin block
assembly 2501. The
pin guide 2514 includes a first hole 2519 and a second hole 2521. The femoral
pin block
assembly 2501 may be similar to the femoral pin guide assembly 1501 of FIG.
9A. The first hole
2519 includes a longitudinal slot 2523. The first hole 2519 receives the pin
sleeve 2515. The first
hole 2519 may be parallel to the bone contacting surface 2518 of the base
2502, or a
theoretical bone contacting plane defined by spikes 2538 protruding from the
bone contacting
surface of the base. The second hole 2521 is anteriorly spaced apart from the
first hole. The
second hole 2521 may be parallel to the bone contacting surface 2518 of the
base 2502, or a
theoretical bone contacting plane defined by spikes 2538 protruding from the
bone contacting
surface of the base, parallel to the first hole 2519, or aligned to correspond
to the upcoming
anterior femoral resection 214, in other words coplanar with the anterior
femoral resection
214. The second hole 2521 may be located so that a guide wire, k-wire, pin,
drill, or the like
passed through the second hole is aligned with the bone contacting surface
2518 of the base
2502, or a theoretical bone contacting plane defined by spikes 2538 protruding
from the bone
contacting surface of the base, or the anterior femoral resection 214 (which
may be at an angle
to the bone contacting surface 2518 or the theoretical bone contacting plane).
Preferably, the
second hole 2521 is located so that the guide wire, etc. exits the anterior
femoral cortex at the
distal edge 2517 of the base 2502. The second hole 2521 may be used to confirm
that the distal
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anterior femoral resection 214, discussed below, will intersect the distal
anterior femoral cortex
at a satisfactory location. This ensures that the distal anterior femoral
resection 214 is not too
deep, so that it notches the anterior femur, and not too shallow, so that the
final implant sits
above the bone surface.
[00162] In an alternate arrangement, the hole 2519 may be parallel to the
femoral
transverse plane, or in other words, perpendicular to the upcoming distal
femoral resection
206. The hole 2521 may also be parallel to the femoral transverse plane, or in
other words,
perpendicular to the distal femoral resection 206. Optionally, the femoral pin
block assembly
2501 may enable the first and second holes to be adjusted, together or
separately, with respect
to the bone contacting surface 2518 and/or with respect to the mechanical axis
202 of the
femur/leg. Preferably, the adjustability occurs between the distal part of pin
guide 2514 and
the distal part of base 2502.
[00163] FIG. 42 shows the step of placing a femoral pin 2505 into the
distal femur through
the pin sleeve 2515 and the first hole 2519 of the femoral pin block assembly
2501. This step
may be similar to or identical to the step of FIG. 10. The femoral pin 2505
encodes information
about 1) the proper varus/valgus orientation of the distal femoral resection
206, 2) the
flexion/extension orientation of the distal anterior femoral resection 214 and
the distal
posterior femoral resection 220, 3) the middle of the trochlear groove
(Whiteside's line). The
femoral pin 2505 enables rotational adjustment of the femoral four-in-one cut
guide assembly
3010 about the pin 2505, which ensures proper tracking of the patella. More
specifically, the
femoral four-in-one cut guide assembly 3010 may be adjusted for varus-valgus
rotation about
the femoral post 3122, which rotates within the hole 3004 created by the
femoral pin 2505. The
distal femoral resection 206, distal anterior femoral resection 214, distal
posterior femoral
resection 220, femoral four-in-one cut guide assembly 3010, femoral post 3122,
and hole 3004
are discussed in greater detail below. FIG. 42 also shows the step of placing
a femoral pin 2507
into the distal femur through the second hole 2521. The femoral pin 2507 may
be placed into
the distal femur temporarily to verify that the distal anterior femoral
resection 214 will
intersect the distal anterior femoral cortex at a satisfactory location, and
then removed. The
femoral pin 2505 is preferably a 5 mm diameter drill. The femoral pin 2507 is
preferably a 3.2
mm diameter pin. Note that the femoral pin block assembly 2501 is not pinned
to the anterior
surface of the femur 100.
[00164] FIG. 43 shows the step of removing the pin sleeve 2515 from the
first hole 2519
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after the femoral pin 2505 has been placed into the distal femur. This step
may be similar to or
identical to the step of FIG. 11. FIG. 43 also shows the step of removing the
femoral pin 2507
from the second hole 2521.
[00165] FIG. 44 shows the step of removing the femoral pin block assembly
2501 after the
femoral pin 2505 has been placed into the distal femur and the pin sleeve 2515
has been
removed from the first hole 2519. This step may be similar to or identical to
the step of FIG. 12.
The femoral pin 2505 slides laterally out of the first hole 2519 through the
slot 2523 (FIG. 41B).
In other words, the femoral pin block assembly 2501 slides anteriorly off of
the femoral pin
2505.
[00166] FIGS. 45A-45B show the step of setting the knee angle to 90 degrees
with a knee
angle guide 2930. FIG. 45A is a perspective view and FIG. 45B is a side view.
The knee angle
guide 2930 includes a knee angle frame 2932 and a rod 2934. The knee angle
frame 2932
includes a hole 2936 which receives the femoral pin 2505 and bilateral holes
2938, 2940 which
receive the rod 2934. The hole 2938 is used with a right knee and the hole
2940 is used with a
left knee as illustrated. The holes 2938, 2940 are parallel to each other.
Referring to FIG. 45B,
the femoral pin 2505 has a central longitudinal axis 2942. The rod 2934 has a
central
longitudinal axis 2944. The orientation of axis 2944 is set by hole 2940 which
receives the rod
2934, or hole 2938 for a right knee. A 90 degree angle 2946 exists between
axis 2944 and axis
2948 of the left arm 2950 of the knee angle frame 2932. A small acute angle
2952 may
optionally exist between axis 2942 and 2948. The angle 2952 may be greater
than or equal to
zero degrees. The illustrated angle 2952 is 3 degrees. In other words, the
illustrated axis 2942 is
parallel to the distal anterior femoral cortex, thus parallel to the distal
anterior femoral
resection 214, and is at an angle of 3 degrees to the distal femoral resection
206. In other
examples, the axis 2942 may be perpendicular to the distal femoral resection
206 and would
thus form a small acute angle with the distal anterior femoral resection 214.
The illustrated
knee angle guide 2930 holds the rod 2934 (axis 2944) parallel to the distal
femoral resection
206 so that when the proximal tibial resection 210 is made, its slope is
accurate.
[00167] FIG. 46 shows the step of coupling a distal femoral cut guide
assembly 2960 to the
femur 100. The distal femoral cut guide assembly 2960 includes a distal plate
2962, a distal
femoral cut guide 2964, and an interlock 2966. The distal plate 2962 slides
over the femoral pin
2505. The interlock 2966 couples the distal femoral cut guide 2964 to the
distal plate 2962 so
that the distal femoral cut guide 2964 is free to slide in the anterior-
posterior direction relative
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to the distal plate 2962. Two pins 2968, 2970 are shown securing the distal
femoral cut guide
2964 to the femur 100.
[00168] FIGS. 47A-47B show exploded perspective views of the distal femoral
cut guide
assembly 2960. The distal plate 2962 includes a medial plate portion 2972, a
lateral plate
portion 2974, and holes 2976, 2978, 2980, 2982, 2984. The distal femoral cut
guide 2964
includes a slot 2986, holes 2988, 2990, and holes 2992, 2994, 2996. Each of
the holes 2992,
2994, 2996 may optionally be a cluster of holes as shown. The interlock 2966
includes a body
2998 and two posts 3000, 3002. The femoral pin 2505 is received in hole 2976.
The post 3000 is
received in holes 2988 and 2978. The post 3002 is received in holes 2990 and
2980. The pin
2968 is received in hole 2992 or another hole in its cluster. The pin 2970 is
received in hole
2994 or another hole in its cluster. Another pin (not shown) may optionally be
received in hole
2996 or another hole in its cluster. A saw blade (not shown) is received in
the slot 2986 to make
a distal femoral resection 206.
[00169] FIG. 48 shows the step of removing the interlock 2966, the distal
plate 2962, the
femoral pin 2505, and making a distal femoral resection 206. The distal
femoral resection 206 is
made through the saw slot 2986 in the distal femoral cut guide 2964. Removing
the femoral pin
2505 leaves a hole 3004 in the distal femur. The hole 3004 is anterior to the
femoral
intrannedullary canal in dense strong subtrochlear bone.
[00170] FIGS. 49A-49D show the step of coupling a femoral four-in-one cut
guide assembly
3010 to the femur 100 and a proximal tibial cut guide 3012 to the tibia 104.
This step may be
similar to the step of FIG. 14A. FIG. 49A is a perspective view. FIG. 49B is a
detail view of a
portion of FIG. 49A. FIG. 49C is a front view. FIG. 49D is a side view. The
four-in-one cut guide
assembly 3010 is an adjustable assembly. The four-in-one cut guide assembly
3010 includes an
anterior cut guide 3014, an anterior chamfer guide 3016, a posterior chamfer
guide 3018, a
posterior cut guide 3020, a gear assembly 3022, and a screw 3024. Four screws
3024 are
shown, two in the anterior chamfer guide 3016 and two in the posterior chamfer
guide 3018.
The four-in-one cut guide assembly 3010 and the proximal tibial cut guide 3012
are adjustably
coupled together by a latch mechanism 3026. The proximal tibial cut guide 3012
is coupled to a
tibial extension rod assembly 2511. The tibial extension rod assembly 2511
includes an outer
rod 2605, an inner rod 2607, a sleeve 2611, a ring 2613, a pin 2601, and a
ball 2617. The tibial
extension rod assembly 2511 may be similar to or identical to the tibial
extension rod 313, 511,
1511 or the femoral extension rod 306, 506, 1506, 2506. The ball 2617 rests in
the target 2882
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so that the tibial extension rod assembly 2511 extends over the center of the
distal tibia 104.
The femoral four-in-one cut guide assembly 3010 and the proximal tibial cut
guide 3012 may be
adjusted for varus-valgus rotation about the femoral post 3122 in the hole
3004 to position the
ball 2617 in the target 2882.
[00171] FIGS. 50A-50D show the femoral four-in-one cut guide assembly 3010,
the proximal
tibial cut guide 3012, and the latch mechanism 3026. FIGS. 50A-50B are
perspective views. FIGS.
50C-50D are exploded perspective views. The proximal tibial cut guide 3012
includes a body
3028 with a proximal undercut channel 3030 defined by side walls 3032, 3034, a
saw slot 3036,
holes 3038, 3040, 3042, a distal arm 3044 which bifurcates into arms 3046,
3048, which are
separated by a slot 3050, and terminates in a compliant pin receiver 3052. The
slot 3050 may
receive the tibial pin 1507 in the manner shown in FIG. 14A. The pin receiver
3052 receives pin
2601 of the tibial extension rod assembly 2511. The holes 3038, 3040, 3042 may
be clusters of
holes as shown. The latch mechanism 3026 includes a body 3054, a lever 3056,
and pins 3058,
3060. The body 3054 includes a proximal undercut rail 3062, a distal undercut
rail 3064, a grip
portion 3066, a recess 3068, and holes 3070, 3072. The lever 3056 includes a
tooth 3074, a
notch 3076, a button 3078, a hole 3080, and a spring arm 3082. The lever 3056
is received in
the recess 3068 with the tooth 3074 opposite the grip portion 3066 and the
button 3078
exposed. The pin 3060 is received in the hole 3070 and the notch 3076. The pin
3058 is received
in the holes 3072, 3080. The distal undercut rail 3064 is received in the
proximal undercut
channel 3030 so that the proximal tibial cut guide 3012 may be adjusted
relative to the femoral
four-in-one cut guide assembly 3010 in the proximal-distal or superior-
inferior direction
(relative to the femur).
[00172] Optionally, for the purpose of making a provisional tibial
resection 209, the proximal
tibial cut guide 3012 can be positioned anterior and distal to its illustrated
position in FIG. 50A,
in other words distal to the posterior cut guide 3020, so that the undercut
channel 3180 and
the undercut channel 3030 are aligned to form a continuous undercut channel so
that the
proximal tibial cut guide 3012 may be adjusted relative to the femoral four-in-
one cut guide
assembly 3010 in the proximal-distal or superior-inferior direction (relative
to the femur). The
latch mechanism 3026 including body 3054 and lever 3056 would of course be
reconfigured to
complement this arrangement.
[00173] Optionally, the femoral four-in-one cut guide assembly 3010 and the
proximal tibial
cut guide 3012 may be combined together as a five-in-one cut guide assembly.
In this
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arrangement, the proximal tibial cut guide 3012 may be adjustable relative to
the femoral four-
in-one cut guide assembly 3010 in the anterior-posterior direction (relative
to the femur), and
may also be adjustable in the proximal-distal direction. The gear assembly
3022 would of
course be reconfigured with additional gears and a rack to complement this
arrangement.
[00174] FIGS. 51A-51E show the femoral four-in-one cut guide assembly 3010.
FIG. 51A is a
front view. FIG. 51B is a cross sectional view taken along line 51B-51B of
FIG. 51A. FIG. 51C is a
cross sectional view taken along line 51C-51C of FIG. 51A. FIGS. 51D-51E are
exploded
perspective views. The anterior cut guide 3014 includes a medial saw slot
3124, a lateral saw
slot 3126, a plate 3128 with a medial rack 3130, a generally rectangular hole
3132, a round hole
3134, a boss 3136, and a femoral post 3122. The generally rectangular hole
3132 includes a
medial channel 3250 and a lateral channel 3252. The femoral post 3122 is shown
as a separate
part coupled to the boss 3136, but the femoral post 3122 may be integrally
formed with the
boss 3136. The illustrated femoral post 3122 is oriented to match a femoral
pin 2505 that is
parallel to the bone contacting surface 2518, or theoretical bone contacting
plane, however the
femoral post 3122 may be oriented to match a femoral pin 2505 that is parallel
to the femoral
transverse plane, or in other words, perpendicular to the distal femoral
resection 206.
Optionally, the femoral four-in-one cut guide assembly 3010 may be designed
with a through
hole, similar to hole 2976 of distal plate 2962, instead of the femoral post
3122 and boss 3136.
The through-hole design may affect many of the parts in the assembly 3010. The
anterior
chamfer guide 3016 includes a medial saw slot 3138, a lateral saw slot 3140,
holes 3142, 3144,
holes 3146, 3148, 3150, 3152, and a generally rectangular channel 3154. The
holes 3142, 3144
receive screws 3024. The holes 3146, 3148, 3150, 3152 may receive bone screws
(not shown)
and may be counterbored as shown so that bone screw heads do not occlude the
saw slots
3138, 3140. The generally rectangular channel 3154 includes a medial channel
3254, a lateral
channel 3256, a medial lip 3262, and a lateral lip 3264. The posterior chamfer
guide 3018
includes a medial saw slot 3156, a lateral saw slot 3158, holes 3160, 3162,
holes 3164, 3166,
3168, 3170, and a generally rectangular channel 3172. The holes 3160, 3162
receive screws
3024. The holes 3164, 3166, 3168, 3170 may receive bone screws (not shown) and
may be
counterbored as shown so that bone screw heads do not occlude the saw slots
3156, 3158. By
placing bone screws through some or all of holes 3146, 3148, 3150, 3152, 3164,
3166, 3168,
3170, the anterior chamfer guide 3016 and posterior chamfer guide 3018 are
locked in place
during the sawing process. The bone screws may serve in lieu of, and may be
replaced by, a
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locking mechanism in the femoral four-in-one cut guide assembly 3010. The bone
screws or
locking mechanism serve to isolate the gear assembly 3022 from loads generated
during the
sawing process. The generally rectangular channel 3172 includes a medial
channel 3258, a
lateral channel 3260, a medial lip 3266, and a lateral lip 3268. The plate
3128 slides against the
inner surfaces of the lips 3262, 3264, 3266, 3268. The posterior cut guide
3020 includes a
medial saw slot 3174, a lateral saw slot 3176, a generally rectangular socket
3178, and a distal
undercut channel 3180 defined by side walls 3182, 3184. The proximal undercut
rail 3062 is
received in the distal undercut channel 3180 so that the proximal tibial cut
guide 3012 may be
adjusted relative to the femoral four-in-one cut guide assembly 3010 in the
proximal-distal or
superior-inferior direction (relative to the femur). The gear assembly 3022 is
received in the
hole 3132, channels 3154, 3172, and socket 3178.
[00175] The femoral post 3122 may optionally be included on a bone-facing side
of a
conventional four-in-one cut guide, integrally formed or as a separate part,
for engagement
with the hole 3004. Alternatively, the conventional four-in-one cut guide may
optionally include
a through hole that receives the femoral pin 2505. Any of these optional
arrangements enable
the conventional four-in-one cut guide to be rotationally adjusted in the
manner described
herein for the femoral four-in-one cut guide assembly 3010.
[00176] FIGS. 52A-52B are exploded perspective views of the gear assembly
3022. The gear
assembly 3022 includes a housing 3084, a bolt 3086, a bolt head pin 3088, an
optional second
bolt head pin 3090, a saddle block 3092, an anterior rack 3094, a posterior
rack 3096, a first
medial gear 3098, a second medial gear 3100, a third medial gear 3102, a first
lateral gear 3104,
a second lateral gear 3106, a third lateral gear 3108, a fourth lateral gear
3110, a first shaft
3112, a second shaft 3114, a third shaft 3116, a fourth shaft 3118, and a
fifth shaft 3120.
[00177] The housing 3084 includes holes 3188, 3190, 3192, 3194, 3196, 3198,
3200, 3202,
3204, rectangular bosses 3206, 3208, a medial rail 3210, a lateral rail 3212,
and a window 3214.
The hole 3188 receives the bolt 3086. The hole 3190 receives the bolt head pin
3088. The
optional hole 3192 receives the optional second bolt head pin 3090. The boss
3206 surrounds
the hole 3194. The boss 3208 surrounds the hole 3196. The medial rail 3210 is
received in the
medial channels 3250, 3254, 3258. The lateral rail 3212 is received in the
lateral channels 3252,
3256, 3260. Preferably, the rails 3210, 3212 and channels 3250, 3252, 3254,
3256, 3258, 3260
are complementary undercut shapes, such as dovetails (illustrated). The
undercut engagement
acts to prevent the generally rectangular channels 3154, 3172 from spreading
during heavy use.
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[00178] The bolt 3086 includes a head 3216, a circumferential groove 3218,
a shaft 3220,
and a torque drive feature 3222. The groove 3218 receives the bolt head pin
3088 and the
optional second bolt head pin 3090, if present. The shaft 3220 is at least
partially threaded from
the end opposite the head 3216.
[00179] The saddle block 3092 includes a generally rectangular body 3224, a
threaded hole
3226, a boss 3228, and an indentation 3229. The body 3224 is received in the
window 3214 so
that the boss 3228 protrudes from the housing 3084 near the rails 3210, 3212
and the
indentation 3229 faces the first medial gear 3098. The threaded hole 3226
receives the shaft
3220. The boss 3228 is received in the hole 3134.
[00180] The anterior rack 3094 includes a rack 3230, a hole 3232, and a
hole 3234. The holes
3232, 3234 receive screws 3024.
[00181] The posterior rack 3096 includes a rack 3236, a hole 3238, and a hole
3240. The
holes 3238, 3240 receive screws 3024.
[00182] Referring to FIGS. 51B-51C, the medial rack 3130 meshes with the
first medial gear
3098, which is mounted on a hexagonal boss of the second lateral gear 3106.
The second lateral
gear 3106 thus rotates with the first medial gear 3098. The second lateral
gear 3106 meshes
with the first lateral gear 3104, which meshes with the anterior rack 3094,
which is fastened to
the anterior chamfer guide 3016 with screws 3024. The second lateral gear 3106
also meshes
with the third lateral gear 3108. The third lateral gear 3108 meshes with the
fourth lateral gear
3110, which is mounted on a hexagonal boss of the second medial gear 3100. The
second
medial gear 3100 thus rotates with the fourth lateral gear 3110. The second
medial gear 3100
meshes with the third medial gear 3102, which meshes with the posterior rack
3096, which is
fastened to the posterior chamfer guide 3018 with screws 3024.
[00183] The first shaft 3112 bears the first medial gear 3098 and the
second lateral gear
3106. The first shaft 3112 is received in hole 3196. The second shaft 3114
bears the second
medial gear 3100 and the fourth lateral gear 3110. The second shaft 3114 is
received in hole
3198. The third shaft 3116 bears the third medial gear 3102. The third shaft
3116 is received in
hole 3200 and is cantilevered in the window 3214. The fourth shaft 3118 bears
the first lateral
gear 3104. The fourth shaft 3118 is received in hole 3202 and is cantilevered
in the window
3214. The fifth shaft 3120 bears the third lateral gear 3108. The fifth shaft
3120 is received in
hole 3204 and is cantilevered in the window 3214.
[00184] The four-in-one cut guide assembly 3010 can be adjusted to position
the saw slots
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3138, 3140, 3156, 3158, 3174, 3176 of the guides 3016, 3018, 3020
(respectively) to correspond
to the progressive arrangement of resection surfaces for the range of femoral
component sizes
of a knee system. The saw slots 3124, 3126 of the anterior cut guide 3014 are
stationary with
respect to the femur 100 because in use the femoral post 3122 is in the
femoral hole 3004. In
the example shown, the anterior-posterior location of each guide 3016, 3018,
3020 is
independently adjustable relative to the anterior cut guide in a controlled
and synchronized
manner. The guides are independently adjustable because each guide may move
relative to the
anterior cut guide at its own rate or speed. The adjustments made to each
guide are controlled
and synchronized by the gear assembly 3022 so that turning the bolt 3088
clockwise and
counterclockwise causes each guide to move at its own speed, and the relative
speeds of the
guides are selected so that when the four-in-one cut guide assembly 3010 is
adjusted to a
particular size, the saw slots are all positioned to correspond to that size.
Note the indicia 3186
shown on the housing 3084 in FIG. 52A to indicate prosthesis sizes. An
audible, visual, or tactile
feedback may be provided to positively indicate that the femoral four-in-one
cut guide
assembly 3010 is set to a discrete implant size. Optionally, in an arrangement
that lacks such
positive indicators, a spacer may be used to verify that the femoral four-in-
one cut guide
assembly 3010 is set to a discrete implant size. As one example, a spacer may
have one or more
prongs, plates, or fingers that engage one or more of the gaps 3015, 3017,
3019 (FIGS. 53C-
53D) that occur between the anterior cut guide 3014, the anterior chamfer
guide 3016, the
posterior chamfer guide 3018, and the posterior cut guide 3020 of the femoral
four-in-one cut
guide assembly 3010. The spacer may be removed before making any resections.
The relative
speeds of the guides are a matter of design choice and will change from one
knee system to the
next. The example shown provides proportional motion of the guides 3016, 3018,
3020 relative
to the anterior cut guide 3014. It is also contemplated that non-proportional
motion may be
provided, so that one or more of the guides may move sometimes faster and
sometimes
slower, according to the design rationale of the particular knee system.
[00185] FIGS. 53A-53D show the step of adjusting the femoral four-in-one
cut guide
assembly 3010, adjusting the proximal tibial cut guide 3012, and pinning the
femoral four-in-
one cut guide assembly 3010 and the proximal tibial cut guide 3012 to the
femur 100 and the
tibia 104, respectively. The femoral four-in-one cut guide assembly 3010 and
the proximal tibial
cut guide 3012 may be adjusted for varus-valgus rotation about the femoral
post 3122 in the
hole 3004. The femoral four-in-one cut guide assembly 3010 may be adjusted for
size by
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rotating the bolt 3088 clockwise and counterclockwise to change the anterior-
posterior
locations of the saw slots 3138, 3140, 3156, 3158, 3174, 3176 of the guides
3016, 3018, 3020
(respectively). The proximal tibial cut guide 3012 is coupled to the femoral
four-in-one cut
guide assembly 3010 by the latch mechanism 3026, which fixes the saw slot 3036
a
predetermined anterior-posterior distance from the saw slots 3174, 3176 and
allows the
proximal tibial cut guide 3012 to slide in and out over the tibial plateau.
Preferably, the femoral
four-in-one cut guide assembly 3010 is adjusted by first rotating the bolt
3088 until the femoral
four-in-one cut guide assembly 3010 is in its closed or smallest state (shown
in FIGS. 49A-51C)
and then rotating the bolt 3088 in the opposite direction to move the femoral
four-in-one cut
guide assembly 3010 toward its fully open or largest state, until the proximal
tibial cut guide
3012 contacts the provisional tibial resection 209 (shown in FIGS. 538-54). At
this point, if the
femoral four-in-one cut guide assembly 3010 is between sizes, the bolt 3088
may be rotated to
adjust the femoral four-in-one cut guide assembly 3010 to the next smaller
size. Pins 3242,
3244, 3246, 3248 secure the femoral four-in-one cut guide assembly 3010 and
the proximal
tibial cut guide 3012 to the femur 100 and tibia 104, respectively. Pin 3242
is received in hole
3194, pin 3244 is received in hole 3038, pin 3246 is received in hole 3040,
and pin 3248 is
received in slot 3050.
[00186] FIG. 54 shows the step of making an anterior femoral resection 214,
an anterior
chamfer cut 216, a posterior chamfer cut 218, a posterior femoral resection
220, and a proximal
tibial resection 210. The anterior femoral resection 214 is made through the
saw slots 3124,
3126 in the anterior cut guide 3014. The anterior chamfer cut 216 is made
through the saw
slots 3138, 3140 in the anterior chamfer guide 3016. The posterior chamfer cut
218 is made
through the saw slots 3156, 3158 in the posterior chamfer guide 3018. The
posterior femoral
resection 220 is made through the saw slots 3174, 3176 in the posterior cut
guide 3020. The
proximal tibial resection 210 is made through the saw slot 3036 in the
proximal tibial cut guide
3012.
[00187] FIG. 55 shows the step of removing the femoral four-in-one cut
guide assembly
3010, the proximal tibial cut guide 3012, the tibial extension rod assembly
2511, and related
pins after making the anterior femoral resection 214, the anterior chamfer cut
216, the
posterior chamfer cut 218, the posterior femoral resection 220, and the
proximal tibial
resection 210. This step may be similar to or identical to the step of FIG.
32.
[00188] FIG. 56 shows the step of implanting a femoral component 130, a
tibial component
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132, an articular insert 134, and a patellar component 136 in the prepared
knee joint. This step
may be similar to or identical to the step of FIG. 88 of U.S. Patent
Application No. 15/081828.
The femoral component 130 is fixed to the distal femur 100, the tibial
component 132 is fixed
to the proximal tibia 104, the articular insert 134 is coupled to the tibial
component 132, and
the patellar component 136 is fixed to the patella 112. The implant components
shown in FIG.
56 are one example of a set of implant components for knee arthroplasty. A
subset of the
components shown may also be used. Uniconnpartnnental components may also be
used.
[00189] FIG. 57 shows the step of converting from an intrannedullary
referencing system or
other conventional referencing system to the system disclosed herein by
coupling another
femoral pin block assembly 3270 of the present system to a distal femoral cut
guide 3272 of the
conventional referencing system and placing a femoral pin 2505 into the distal
femur through
the pin sleeve 2515. This step may take place instead of the steps of coupling
the femoral pin
block assembly 2501 to the anterior distal femur, as shown in FIG. 40A, and
placing the femoral
pin 2505 into the distal femur through the pin sleeve 2515 and the first hole
2519 of the
femoral pin block assembly 2501, as shown in FIG. 42. The step of FIG. 57 may
result in
equivalent positioning of the femoral pin 2505 in the distal femur, as shown
in FIG. 44,
including formation of an equivalent hole 3004. The step of FIG. 57 may occur
after a distal
femoral resection 206 and a provisional proximal tibial resection 209 have
been made.
[00190] FIGS. 58A-58B are exploded perspective views of the femoral pin
block assembly
3270 and the distal femoral cut guide 3272. The femoral pin block assembly
3270 includes a
body 3274, the pin sleeve 2515, an anterior referencing pin 3276, and a
thumbscrew 3278.
[00191] The body 3274 includes a pin guide arm 3280, a distal femoral paddle
3282, and an
anterior referencing arm 3284. The pin guide arm 3280 includes a first hole
3286 with a
longitudinal slot 3288, equivalent to the first hole 2519 and longitudinal
slot 2523. The first hole
3286 receives the pin sleeve 2515, which receives the femoral pin 2505. The
slot 3288 is wider
than the femoral pin 2505. The pin guide arm 3280 may include an optional
second hole (not
shown) equivalent to the second hole 2521. The anterior referencing arm 3284
includes a first
hole 3290, a slot 3292, and a second hole 3294. The first hole 3290 receives
the anterior
referencing pin 3276. The slot 3292 splits the first hole 3290 longitudinally
and bifurcates the
free end of the arm 3284. The second hole 3294 extends through the bifurcated
free ends of
the arm 3284 transverse to the first hole 3290. The second hole 3294
threadedly receives the
thumbscrew 3278, which can be tightened so that the first hole 3290 grips the
anterior
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referencing pin 3276, or loosened so that the anterior referencing pin is
movable within the
first hole.
[00192] The anterior referencing pin 3276 extends between a narrow distal end
3296 and a
broad proximal end 3298. The distal end 3296 contacts the anterior distal
femoral cortex in use,
while the proximal end 3298 serves as a handle. The distal end 3296 may taper
to a point as
shown. The proximal end 3298 may include grip features 3300 such as grooves
(shown),
knurling, threads, bumps, or a rough surface texture. The anterior referencing
pin 3276 may
optionally include indicia 3302, best seen in the enlarged detail provided in
FIG. 588. The indicia
3302 may include reference lines, numerals, icons, or other marks.
[00193] The distal femoral cut guide 3272 includes a saw slot 3304, pin
holes 3306, 3308,
3310, and holes 3312, 3314. The saw slot 3304 receives a saw blade (not shown)
to make the
distal femoral resection 206. The saw slot 3304 also receives the distal
femoral paddle 3282 as
shown in FIG. 57. The pin holes 3306, 3308, 3310 receive bone pins 3316. Each
pin hole 3306,
3308, 3310 may be a cluster of holes as shown. Indicia 3318 may be present.
[00194] Any methods disclosed herein comprise one or more steps or actions for
performing
the described method. The method steps and/or actions may be interchanged with
one
another. In other words, unless a specific order of steps or actions is
required for proper
operation of the embodiment, the order and/or use of specific steps and/or
actions may be
modified.
[00195] Reference throughout this specification to "an embodiment" or "the
embodiment"
means that a particular feature, structure or characteristic described in
connection with that
embodiment is included in at least one embodiment. Thus, the quoted phrases,
or variations
thereof, as recited throughout this specification are not necessarily all
referring to the same
embodiment.
[00196] Similarly, it should be appreciated that in the above description
of embodiments,
various features are sometimes grouped together in a single embodiment,
figure, or description
thereof for the purpose of streamlining the disclosure. This method of
disclosure, however, is
not to be interpreted as reflecting an intention that any claim in this or any
application claiming
priority to this application require more features than those expressly
recited in that claim.
Rather, as the following claims reflect, inventive aspects lie in a
combination of fewer than all
features of any single foregoing disclosed embodiment. Thus, the claims
following this Detailed
Description are hereby expressly incorporated into this Detailed Description,
with each claim
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standing on its own as a separate embodiment. This disclosure includes all
permutations of the
independent claims with their dependent claims.
[00197] Recitation in the claims of the term "first" with respect to a
feature or element does
not necessarily imply the existence of a second or additional such feature or
element. Elements
recited in means-plus-function format are intended to be construed in
accordance with 35
U.S.C. 112 Para. 6. It will be apparent to those having skill in the art that
changes may be made
to the details of the above-described embodiments without departing from the
underlying
principles of the technology.
[00198] While specific embodiments and applications of the present
technology have been
illustrated and described, it is to be understood that the technology is not
limited to the precise
configuration and components disclosed herein. Various modifications, changes,
and variations
which will be apparent to those skilled in the art may be made in the
arrangement, operation,
and details of the methods and systems of the technology disclosed herein
without departing
from the spirit and scope of the invention as claimed.
