U.S. patent application number 14/515162 was filed with the patent office on 2015-04-23 for ligament guide registration.
The applicant listed for this patent is Biomet Manufacturing, LLC. Invention is credited to Ryan J. SCHOENEFELD.
Application Number | 20150112349 14/515162 |
Document ID | / |
Family ID | 52826823 |
Filed Date | 2015-04-23 |
United States Patent
Application |
20150112349 |
Kind Code |
A1 |
SCHOENEFELD; Ryan J. |
April 23, 2015 |
Ligament Guide Registration
Abstract
A patient-specific guide tool for guiding an instrument toward a
bone for implantation of a prosthetic device is disclosed. The
guide tool includes a body portion having a guide element, and a
patient-specific portion having at least one patient-specific
mating feature that is configured to engage a soft tissue at or
near the bone. A method of manufacturing a guide tool for guiding
an instrument toward a bone is also disclosed.
Inventors: |
SCHOENEFELD; Ryan J.; (Fort
Wayne, IN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Biomet Manufacturing, LLC |
Warsaw |
IN |
US |
|
|
Family ID: |
52826823 |
Appl. No.: |
14/515162 |
Filed: |
October 15, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61893570 |
Oct 21, 2013 |
|
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Current U.S.
Class: |
606/88 ;
700/98 |
Current CPC
Class: |
A61B 17/157 20130101;
A61B 2034/108 20160201; A61B 17/1666 20130101; A61B 17/1764
20130101; A61B 2017/568 20130101; A61B 17/154 20130101; A61B 17/17
20130101 |
Class at
Publication: |
606/88 ;
700/98 |
International
Class: |
A61B 17/15 20060101
A61B017/15; G06F 17/50 20060101 G06F017/50; A61B 17/17 20060101
A61B017/17 |
Claims
1. A patient-specific guide tool for guiding an instrument toward a
bone, the guide tool comprising: a body portion that includes an
engagement surface and a guide element configured to guide movement
of the instrument toward the bone; and a patient-specific soft
tissue attachment portion that is coupled to the body portion, the
patient-specific soft tissue attachment portion including at least
one patient-specific soft tissue mating feature that is configured
to engage a first soft tissue at or near the bone to thereby
position the engagement surface at a predetermined position
relative to the bone.
2. The patient-specific guide tool according to claim 1, further
comprising a second patient-specific soft tissue mating feature
that is configured to engage a second soft tissue at or near the
bone, wherein the second soft tissue is different from the first
soft tissue.
3. The patient-specific guide tool according to claim 2, further
comprising a third patient-specific soft tissue mating feature that
is configured to engage a third soft tissue at or near the bone,
wherein the third soft tissue is different from the first and
second soft tissues.
4. The patient-specific guide tool according to claim 3, wherein
the first patient-specific soft tissue mating feature is configured
to engage an anterior cruciate ligament (ACL), the second
patient-specific soft tissue mating feature is configured to engage
medial collateral ligament (MCL), the third patient-specific soft
tissue mating feature is configured to engage a lateral cruciate
ligament (LCL), and wherein the engagement surface is configured to
engage a tibia.
5. The patient-specific guide tool according to claim 1, wherein
the patient-specific soft tissue mating feature is configured to
engage a transacetabular ligament and the engagement surface is
configured to engage an acetabulum.
6. The patient-specific guide tool according to claim 5, wherein
the engagement surface includes a rim portion that is a negative of
an acetabular rim, the rim portion configured to engage the
acetabular rim in only one position.
7. The patient-specific guide tool according to claim 1, wherein
the soft tissue mating feature is a hook, notch, slit, slot, or
tab.
8. The patient-specific guide tool according to claim 1, wherein
the soft tissue mating feature is configured to engage a ligament,
tendon, muscle, fibrous tissue or fat.
9. The patient-specific guide tool according to claim 1, wherein
the engaging surface is a mirror image of a site on the bone where
the guide tool is to be positioned and nests in only one position
on the bone.
10. The patient-specific guide tool according to claim 1, wherein
the guide element is a guide bore, slot, or guide surface.
11. A patient-specific guide tool for guiding an instrument toward
a bone, the guide tool comprising: a body portion that includes a
guide feature having a guide surface, the guide surface configured
to guide movement of the instrument toward the bone; a first
patient-specific portion extending from the body portion, the first
patient-specific portion including at least one patient-specific
soft tissue engaging feature that is configured and shaped to
engage soft tissue at or near the bone; and a second
patient-specific portion extending from the body portion, the
second patient-specific portion including a patient-specific bone
engaging surface configured to nest with the bone, wherein the
guide tool thereby positions the guide feature at a predetermined
position relative to the bone.
12. The patient-specific guide tool according to claim 11, wherein
the soft tissue engaging feature is configured to engage a
transacetabular ligament.
13. The patient-specific guide tool according to claim 12, wherein
the patient-specific bone engaging surface comprises a concave
surface portion configured to engage and nest with a convex rim of
the acetabulum in only one position.
14. The patient-specific guide tool according to claim 11, further
comprising a second patient-specific soft tissue engaging feature
that is configured to engage a second soft tissue, the second soft
tissue being different from the first soft tissue.
15. The patient-specific guide tool according to claim 14, wherein
the first soft tissue engaging feature is configured to engage an
anterior cruciate ligament and the second soft tissue engaging
feature is configured to engage a medial collateral ligament.
16. The patient-specific guide tool according to claim 15, wherein
the bone engaging surface is configured to engage a tibia.
17. The patient-specific guide tool according to claim 11, wherein
the soft tissue engaging feature is configured in accordance with a
two-dimensional or three-dimensional model of the bone and soft
tissue of a specific patient reconstructed preoperatively from at
least one image scan of the patient.
18. A method of manufacturing a guide tool for use in guiding an
instrument to a bone, the method comprising: obtaining images of at
least a portion of the bone; determining the location of soft
tissue at or near the bone; generating a two-dimensional or
three-dimensional model of the bone and soft tissue; and
fabricating a patient-specific guide tool having a body portion and
a patient-specific portion, the body portion including a guide
feature, and the patient-specific portion including at least one
soft tissue mating feature that is configured to engage the soft
tissue according to the two-dimensional or three-dimensional
model.
19. The method according to claim 19, wherein determining the
location of soft tissue at or near the bone comprises obtaining an
MRI, CT scan or ultrasound of the portion of the bone.
20. The method according to claim 18, wherein determining the
location of soft tissue at or near the bone comprises obtaining an
X-ray of the bone of the specific patient and locating the position
of the soft tissue at or near the bone according to known locations
of the soft tissue relative to the bone.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims benefit of U.S. Provisional Patent
Application No. 61/893,570 filed on Oct. 21, 2013. The entire
disclosure of the above application is incorporated herein by
reference.
FIELD
[0002] The subject disclosure is related to various
patient-specific alignment guides for use in joint replacement,
resurfacing procedures and other procedures related to the joint or
the various bones of the joint, including adjacent bones. A feature
on the patient-specific alignment guides conforms to or engages a
soft tissue to align a guide portion of the guides to a
predetermined position relative to a bone at the joint. The soft
tissue can be a ligament, tendon, muscle, fibrous tissue or fat.
The patient-specific alignment guides are designed and constructed
preoperatively based on two- or three-dimensional images of the
patient's bone and soft tissue at or near a joint.
BACKGROUND
[0003] This section provides background information related to the
present disclosure which is not necessarily prior art.
[0004] Joint reconstruction surgery requires careful planning by a
surgeon and specialized instrumentation. Methods used for
reconstructing a joint sometimes are not sufficiently accurate to
reproduce the natural movement of the joint. Planning for the
surgery is often based on two-dimensional x-ray films and surgeons
often resort to shaping prosthetics during surgery. During the
surgery, the surgeon typically uses non-patient specific alignment
guides to prepare a defect on a bone for implantation of a
prosthesis.
[0005] Recently, patient-specific alignment guides have been
implemented as an alternative to standard orthopedic
instrumentation and planning. The manufacture of patient-specific
guides can require imaging protocols from which three-dimensional
and pre-operative plans are created. These pre-operative plans can
be used to create the patient-specific guides, which generally
"lock" or "nest" into native boney landmarks at the site of the
defect. When used in surgery, the patient-specific guide sits on a
bone surface in order for the surgeon to carry out the
pre-operatively planned procedure.
[0006] Although current patient-specific guides are an improvement
from previous instrumentation, there remains a need for
patient-specific instruments that reference landmarks other than
bone.
SUMMARY
[0007] This section provides a general summary of the disclosure,
and is not a comprehensive disclosure of its full scope or all of
its features.
[0008] A patient-specific guide tool for guiding an instrument
toward a bone for implantation of a prosthetic device is disclosed.
The guide tool comprises a body portion that includes an engagement
surface and a guide feature. The guide feature is configured to
guide movement of the instrument toward the bone. The guide tool
further comprises a patient-specific portion that is coupled to the
body portion. The patient-specific portion includes at least one
patient-specific attachment portion including at least one
patient-specific soft tissue mating feature that is configured to
conform to or engage a first soft tissue at or near the bone to
thereby position the engagement surface at a predetermined position
relative to the bone. The mating feature can be a hook, notch,
slit, slot, or tab. The soft tissue can be a ligament, tendon,
muscle, fibrous tissue, or fat.
[0009] A patient-specific guide tool for guiding an instrument
toward a bone for implantation of a prosthetic device is also
disclosed. The guide tool comprises a body portion and a first
patient-specific portion extending from the body portion. The body
portion can include a guide feature having an elongated bore. The
guide feature is configured to guide movement of the instrument
toward the bone. The first patient-specific portion includes at
least one patient-specific mating feature that is configured to
engage soft tissue at or near the bone in accordance with a
two-dimensional or three-dimensional model of the bone and soft
tissue of a specific patient reconstructed preoperatively from at
least one image scan of the patient. The guide tool further
comprises a second patient-specific portion extending form the body
portion. The second patient-specific portion includes a
patient-specific bone engaging surface. The guide tool thereby
positions the guide feature at a predetermined position relative to
the bone.
[0010] A method of manufacturing a guide tool for guiding an
instrument to a bone is also disclosed. The method comprises
obtaining at least one image of at least a portion of the bone;
determining the location of soft tissue at or near the bone;
generating a two-dimensional or three-dimensional model of the bone
and soft tissue; and fabricating a patient-specific guide tool
having a body portion and a patient-specific portion, the body
portion including a guide feature, and the patient-specific portion
including at least one mating feature that is configured to engage
the soft tissue according to the two-dimensional or
three-dimensional model. Determining the location of soft tissue at
or near the bone can comprise obtaining an MRI, CT scan or
ultrasound of the portion of the bone. Alternatively, determining
the location of soft tissue at or near the bone can comprise
obtaining an X-ray of the bone of the specific patient and locating
the position of the soft tissue at or near the bone according to
known locations of the soft tissue relative to the bone.
[0011] Further areas of applicability will become apparent from the
description provided herein. The description and specific examples
in this summary are intended for purposes of illustration only and
are not intended to limit the scope of the present disclosure.
DRAWINGS
[0012] The drawings described herein are for illustrative purposes
only of selected embodiments and not all possible implementations,
and are not intended to limit the scope of the present
disclosure.
[0013] FIG. 1 is a representation of a patient-specific acetabular
guide;
[0014] FIG. 2 is a representation of a patient-specific acetabular
guide on an acetabulum;
[0015] FIG. 3 is a representation of a patient-specific acetabular
guide comprising a patient-specific rim portion on an
acetabulum;
[0016] FIG. 4 is a a representation of a patient-specific
acetabular guide comprising a patient-specific rim portion having a
pair of guiding elements on an acetabulum;
[0017] FIG. 5 is a representation of a reamer aligned with a pilot
hole in an acetabulum;
[0018] FIG. 6 is a representation of a pelvis having alignment pins
positioned in the pelvis;
[0019] FIG. 7 is a representation of a patient-specific tibial
guide positioned on a proximal end of a tibia;
[0020] FIG. 8 is a representation of a patient-specific tibial
guide with alignment pins inserted through guide elements;
[0021] FIG. 9 is a representation of a proximal end of a tibia with
alignment pins inserted in the anterior face of the tibia;
[0022] FIG. 10 is a representation of a tibial cut block positioned
adjacent to an anterior face of a tibia; and
[0023] FIG. 11 is a representation of a trial plate positioned
adjacent to a superior face of a resected tibia at a proximal
end.
[0024] Corresponding reference numerals indicate corresponding
parts throughout the several views of the drawings.
DETAILED DESCRIPTION
[0025] Example embodiments will now be described more fully with
reference to the accompanying drawings.
[0026] The present teachings generally provide patient-specific
surgical instruments that include, for example, alignment guides,
drill guides, templates, cutting/resection guides for use in joint
replacement, resurfacing procedures and other procedures related to
the joint or the various bones of the joint, including adjacent
bones. A feature on the surgical instruments can be placed in
contact with soft tissue to align a guide portion of the instrument
to a face of a bone at the joint. The soft tissue can be a
ligament, tendon, muscle, fibrous tissue or fat.
[0027] In various embodiments, the joint is a hip. In such
embodiments, the present teachings generally provide a
patient-specific acetabular guide or proximal femoral guide for use
in orthopedic surgery, such as in joint replacement or revision
surgery, for example. The patient-specific alignment guides can be
used either with conventional or patient-specific implant
components prepared with computer-assisted image methods.
[0028] In other embodiments, the joint is a knee. When the joint is
a knee, the patient-specific surgical instruments can be used in
knee joint replacement, resurfacing procedures and other procedures
related to the knee joint or the various bones of the knee joint,
including the femur and the tibia. The present teaching can be
applied to partial and full knee reconstructions.
[0029] In a further embodiment, the joint is a shoulder. When the
joint is a shoulder, the patient-specific surgical instruments can
be used in shoulder joint replacement, resurfacing procedures and
other procedures related to the shoulder joint or the various bones
of the shoulder joint, including the glenoid and adjacent bones.
The present teachings can be applied to anatomic shoulder
replacement and reverse shoulder replacement.
[0030] The patient-specific instruments can be used either with
conventional implant components or with patient-specific implant
components and/or bone grafts that are prepared using
computer-assisted image methods according to the present teachings.
Computer modeling for obtaining two or three dimensional images of
the patient's anatomy using MRI or CT, X-ray, or ultrasound scans
of the patient's anatomy, the patient-specific prosthesis
components and the patient-specific guides, templates and other
instruments, can be designed using various CAD programs and/or
software available, for example, by Materialise USA, of Plymouth,
Mich.
[0031] The patient-specific instruments and any associated
patient-specific implants and bone grafts can be generally designed
and formed using computer modeling based on two or three
dimentional anatomic image(s) generated from X-rays, MRI, CT,
ultrasound or other medical scans. Specifically, an anatomical
feature (e.g., a scapula, knee, or pelvis with surrounding soft
tissue) can be imaged to detect certain features of the anatomy
(e.g., dimensions, curvature of surfaces, soft tissues, etc.).
Then, patient-specific instruments can be formed according to these
measurements. Various pre-operative procedures are disclosed in
commonly assigned U.S. Pat. No. 8,092,465, issued on Jan. 10, 2012,
U.S. patent Publication No. 2011/0184419, published on Jul. 28,
2011, and U.S. Publication No. 2012/0310399, published on Dec. 6,
2012, which are all incorporated herein by reference in their
entirety.
[0032] The patient-specific instrument can have a three-dimensional
engagement feature that is complementary and made to conformingly
contact or engage a soft tissue. In some embodiments, the
patient-specific instrument can further have a three-dimensional
engagement surface that is a mirror image or negative of a boney
surface or cartilage. The three-dimensional engagement surface is
complementary to and made to conformingly contact, engage, or nest
on a bony anatomical surface or cartilage. Thus, the
patient-specific instruments can be configured to fit at only one
position to the anatomical surface. The patient-specific
instruments can include custom-made guiding formations, such as,
for example, guiding bores or cannulated guiding posts or
cannulated guiding extensions or receptacles that can be used for
supporting or guiding other objects, such as instruments, drill
guides, reamers, cutters, cutting guides and cutting blocks or for
inserting pins or other fasteners according to a surgeon-approved
pre-operative plan.
[0033] In various embodiments, the patient-specific instruments can
also include one or more patient-specific alignment guides for
receiving and guiding a tool, such as a drill or pin or guide wire
at corresponding patient-specific orientations relative to a
selected anatomic axis for the specific patient. The
patient-specific instruments can include guiding or orientation
formations and features for guiding the implantation of
patient-specific or off-the-shelf implants associated with the
surgical procedure. The geometry, shape and orientation of the
various features of the patient-specific instruments, as well as
various patient-specific implants and bone grafts, if used, can be
determined during the pre-operative planning stage of the procedure
in connection with the computer-assisted modeling of the patient's
anatomy. During the pre-operative planning stage, patient-specific
instruments, custom, semi-custom or non-custom implants and other
non-custom tools, can be selected and the patient-specific
components can be manufactured for a specific-patient with input
from a surgeon or other professional associated with the surgical
procedure.
[0034] In the following discussion, the terms "patient-specific",
"custom-made" or "customized" are defined to apply to components,
including tools, implants, portions or combinations thereof, which
include certain geometric features, including surfaces, curves, or
other lines, and which are made to closely conform as mirror-images
or negatives or complementary surfaces of corresponding geometric
features or anatomic landmarks of a patient's anatomy obtained or
gathered during a pre-operative planning stage based on two or
three dimensional computer images of the corresponding anatomy
reconstructed from image scans of the patient by computer imaging
or X-ray methods. Further, patient-specific guiding features, such
as, guiding apertures, guiding slots, guiding members or other
holes, openings, or guide surfaces that are included in alignment
guides, drill guides, cutting guides, rasps or other instruments or
in implants are defined as features that are made to have
positions, orientations, dimensions, shapes and/or define cutting
planes and axes specific to the particular patient's anatomy
including various anatomic or mechanical axes based on the
computer-assisted pre-operative plan associated with the
patient.
[0035] The prepared patient-specific alignment guides can be
configured to mate in alignment with natural soft tissue landmarks
by orienting and placing the corresponding alignment guide
intra-operatively at or near the bone to mate with corresponding
soft tissue. In some embodiments, the patient-specific alignment
guides can further be configured to mate in alignment with natural
boney anatomic landmarks by orienting and placing the corresponding
alignment guide intra-operatively on top of the bone to mate with
corresponding boney landmarks, as well as with soft tissue
landmarks. The soft tissue and boney landmarks function as passive
fiducial identifiers or fiducial markers for positioning of the
various alignment guides, drill guides or other patient-specific
instruments.
[0036] The various patient-specific alignment guides can be made of
any biocompatible material, including, polymer, ceramic, metal or
combinations thereof. The patient-specific alignment guides can be
opaque, semi-transparent, or transparent. The patient-specific
alignment guides can be disposable and can be combined or used with
reusable and non patient-specific cutting and guiding
components.
[0037] More specifically, the present teachings provide various
embodiments of patient-specific acetabular, knee, glenoid, or other
appropriate guides. The acetabular, knee, glenoid or other
appropriate guides of the present teachings can have
patient-specific engagement surfaces that reference various
portions of the hip, knee, or shoulder joint and include drill
guides, guiding bores or sleeves or other guiding formations that
can accurately position a guide wire for later acetabular, knee, or
glenoid preparation and implantation procedures and for alignment
purposes, including implant position control, implant version
control, implant inclination control.
[0038] In the following, when of portion of a patient-specific
guide is described as "referencing" a portion of the anatomy, it
will be understood that the referencing portion of the
patient-specific guide is a patient-specific portion or surface
mirroring or negative to the corresponding referenced soft tissue,
cartilage surface and/or bone surface. Exemplary, non-limiting
patient-specific guides are shown, but additional patient-specific
guides can be configured based on the present teachings.
[0039] With reference to FIGS. 1-4, the present teachings provide
various exemplary patient-specific acetabular guides 100, 200, 300.
The acetabular guides 100, 200, 300 can be used in connection with
various other instruments to facilitate guided reaming of an
acetabulum 20 of a pelvis 22 of a specific patient and guided
insertion and implantation of an acetabular implant or acetabular
cup in the acetabulum 20. The patient-specific acetabular guides
100, 200, 300 engage the acetabulum 20 of the specific patient in
only one position and can provide an accurate alignment axis
relative to a planned orientation of an acetabular cup. The
acetabular guides 100, 200, 300 can also provide secure fitting and
rotational stability in a design that is lightweight with minimal
size and bulk.
[0040] FIG. 1 illustrates a patient-specific acetabular guide 100,
having a patient-specific soft tissue mating feature 102, a
patient-specific body 104 with a bone engaging surface 105 and an
opposing surface 107, and a guiding or pilot element 106 having an
elongated bore 108 with a patient-specific alignment axis A. The
soft tissue mating feature 102 can comprise two substantially
parallel plates 112, 114 coupled together at a stop 116 in a
U-shape defining a slot 118. The mating feature 102 is configured
to conform, nest, receive, or engage a soft tissue. While a single
soft tissue mating feature 102 is illustrated, it should be
understood that multiple soft tissue mating features can be
integrated into a single guide and engage multiple distinct soft
tissue areas to provide added stability. In some embodiments, the
bone engaging surface 105 is negative or mirror image of the
surface of the acetabulum 20. When positioned on the acetabulum 20,
the bone engaging surface 105 nests on the boney surface. In other
embodiments, the bone engaging surface 105 does not mirror, or only
slightly mirrors the surface of the acetabulum. In such
embodiments, the acetabular guide 100 is positioned only by the
soft tissue mating feature 102.
[0041] In FIG. 2, the patient-specific acetabular guide 100 is
positioned on the acetabulum 20 of the pelvis 22 with the soft
tissue mating feature 102 mating or engaging with a transverse
acetabular ligament 80. The mating feature 102 can mate or engage
with the transverse acetabular ligament 80 in such a manner that
the ligament 80 contacts the parallel plates 112, 114 and the stop
116, which define the slot 118. The mating feature 102 is
configured to conform, nest, or engage a soft tissue. The alignment
axis A is configured to be central to the acetabulum 20 and
perpendicular to the acetabulum's surface when the guide 100 is
positioned on the acetabulum 21. As mentioned above, the bone
engaging surface 105 may or may not be a negative or mirror image
of the surface of the acetabulum 20.
[0042] The acetabular guide 100 can be provided in various fitment
options depending on the planned exposure of the acetabulum 20 for
the reaming procedure and implantation. Each fitment option can
include a portion that mates with the transverse acetabular
ligament 80, which provides a landmark for rotational stability and
unique positioning on the acetabulum 20. To additionally improve
stability, each fitment option can also include a portion that
covers the acetabular fossa at the center of the acetabulum 20. As
shown in FIGS. 3 and 4, another fitment option for the acetabular
guide includes a rim portion 210, 310 that is complementary to a
portion of an acetabular rim 24. The rim portion 210, 310 can have
a concave surface that references and mates with a convex
acetabular rim 24, thus providing additional stability to guides
200, 300. The rim portion 210, 310 can be a mirror image or
negative of the rim surface 24, enabling the rim portion 210, 310
to nest, engage, or conform to the rim 24. Each fitment option
allows the acetabular guide 100, 200, 300 to have a compact size,
extend through the center of the acetabulum 20 for alignment, and
include portions that can fit over various anatomic landmarks in a
unique position for the patient. The particular fitment option can
be selected for each specific patient based on the patient's
anatomy, the procedure to be performed and the surgeon's preference
and/or technique.
[0043] Referring to FIGS. 1-2, the patient-specific soft tissue
mating portion 102 of the acetabular guide 100 includes a feature
that is functional to reversibly mate with soft tissue, such as a
ligament. The feature can be a hook, notch, slit, slot, or tab. As
shown in detail in FIG. 1, the mating feature 102 can include a
slot 118 formed by two parallel plates 112, 114 and a stop 116 in a
U-shape. The mating feature 102 is designed by using a
two-dimensional or three-dimensional image or model of the
acetabulum 20, surrounding soft tissue, and surrounding pelvic area
of the specific patient, as described above. To avoid costly
digital imaging protocols, the mating feature 102 can be designed
by only an X-ray along with knowledge of the typical location of
the transacetabular ligament or other soft tissue landmarks. Mating
the acetabular guide 100 to the transverse acetabular ligament 80
enables the acetabular guide 100 to be oriented in a unique
position within the acetabulum 20. The acetabular guide 100 can be
designed to have a generally small thickness, such that it can form
a lightweight three-dimensional shell from which the guiding
element 106 extends opposite to the acetabular surface. The guiding
element 106 can be formed to be a monolithic or integral portion of
the acetabular guide 100. Alternatively, the guiding element 106
can be modularly and removably coupled to the acetabular guide 100,
using, for example, a threaded connection, snap-on connectors, or
other removable attachments.
[0044] FIG. 3 shows a patient-specific acetabular guide 200 with an
additional fitment option. The guide 200 includes a
patient-specific soft tissue mating feature 202, a patient-specific
body 204 with a bone engaging surface 205 and an opposing surface
207, and a guiding or pilot element 206 having an elongated bore
208. As illustrated, the acetabular guide 200 is generally similar
to guide 100. Unlike acetabular guide 100, acetabular guide 200
further comprises a patient-specific rim portion 210 that is
complementary to a portion of the acetabular rim 24. In some
embodiments, a concave surface of the rim portion 210 mates with
the convex rim 24. Acetabular guide 200 has a patient-specific soft
tissue mating feature 202, patient-specific body 204, and a
patient-specific rim portion, which collectively impart greater
stability to the guide 200 when it is positioned on an acetabulum
20. In various embodiments, the bone engaging surface 205 of the
body 204 is a mirror image or negative of the surface of the
acetabulum 20, which allows the guide 200 to nest on the articular
surface of the acetabulum 20 to provide further stability.
[0045] FIG. 4. shows a patient-specific acetabular guide 300,
similar to acetabular guide 200. Acetabular guide 300 comprises a
soft tissue mating feature 302, a patient-specific body 304 with a
bone engaging surface 305 and an opposing surface 307, a guiding or
pilot element 306 having an elongated bore 308, and a
patient-specific rim portion 310. In various embodiments, the bone
engaging surface 305 of the body 203 is a mirror image or negative
of the surface of the acetabulum 20, which allows the guide 300 to
nest on the boney surface to provide further stability. Acetabular
guide 300 further includes a second guiding or pilot element 312
having an elongated bore 314, and a third guiding or pilot element
316 having an elongated bore 318. The guiding elements 312, 316 can
be formed to be a monolithic or integral portion of acetabular
guide 300. Alternatively, the guiding elements 312, 316 can be
modularly and removably coupled to the acetabular guide 300, using,
for example, a threaded connection, snap-on connectors, or other
removable attachments. The guiding elements 312, 316 are located at
predetermined locations relative to the acetabulum 20. A surgeon
can drill guide holes and/or insert guide pins through the guiding
elements 312, 316 and into the pelvis 22.
[0046] FIG. 5 shows a pelvis 22 and acetabulum 20 including a pilot
hole 330 in the acetabulum 20, and pilot holes 332, 334 in the
pelvis 22, near the acetabular rim 24. The pilot hole 330 could be
made by drilling through guiding elements 106, 206, 306 of
patient-specific acetabular guides 100, 200, 300 shown in FIGS.
1-3. Pilot hole 330 can be used to guide an instrument, such as a
reamer 336 having a protruding guide feature 338. The reamer can be
properly aligned with the acetabulum 20 by inserting the protruding
guide feature 338 of the reamer 336 into pilot hole 330.
[0047] As shown in FIG. 6, alignment pins 340, 342 can be drilled
into the pelvis 22 by guiding them through guiding elements 312,
316 of the patient-specific acetabular guide 300 shown in FIG. 4. A
secondary guide 350 can be guided down the alignment pins 340, 342
after guide 300 is removed. The secondary acetabular guide 350 can
include a reaming alignment pin inserted into a cannulated feature
352 on the secondary guide 350 having a bore 354. The reaming
alignment pin can be used to further align a reamer, such as the
reamer 336 of FIG. 5, to ensure the reamer 336 is centered relative
to the acetabulum 20, and to ensure the reaming is performed at a
correct angle and orientation in relation to the acetabulum 20 and
the pelvis 22. In various embodiments, the alignment pin can be
coupled to the reamer 336 as a further aid to orient it in a
desired position. Additional embodiments and a more detailed
discussion on the use of the guide bores and pins can be found in
U.S. Patent Publication No. 2012/0226283, published Sep. 6, 2012,
which is incorporated herein by reference.
[0048] With reference to FIG. 7, the present teachings further
provide various exemplary patient-specific tibial guides, such as
patient-specific tibial guide 400. The tibia guide 400 can be used
in connection with various other instruments to facilitate guided
resecting of a proximal end of a tibia of a specific patient and
guided insertion and implantation of a tibial implant. The
patient-specific tibial guides 400 engage the proximal tibia of the
specific patient in only one position. The tibial guides 400 can
also provide secure fitting and rotational stability.
[0049] FIG. 7 illustrates the patient-specific tibial guide 400,
having a first patient-specific soft tissue mating feature 402, a
second patient-specific soft tissue mating feature 404, and
optionally a third patient-specific soft tissue mating feature 406.
The tibial guide 400 also comprises a patient-specific body 408
with a first surface 409 that contacts an anterior surface of a
tibia 410 and a second surface 411 that contacts a superior surface
of a tibia 412, anterior guiding or pilot elements 414, 416 having
elongated bores 418, 420 positioned on the anterior surface 409,
and superior guiding or pilot elements 422, 424 having elongated
bores 426, 428 positioned on the superior surface 411. The soft
tissue mating features 402, 404, 406 comprise substantially
parallel surfaces 409, 411 that are coupled at a stop 413, thereby
forming a U-shaped slot 415. The position of the soft tissue mating
features 402, 404, 406 can be predetermined by referencing three
dimensional CT or MRI scans, or by referencing two-dimensional
X-rays and light of typical ligament locations in a knee. The
patient-specific tibial guide 400 is positioned on a proximal end
90 of a tibia 92 with the first soft tissue mating feature 402
mating with a medial collateral ligament (MCL) 94, the second soft
tissue mating feature 404 mating with an anterior cruciate ligament
(ACL) 96, and the optional third soft tissue mating feature 406
mating with a lateral collateral ligament (LCL) 98 by positioning
the mating features 402, 404, 406 to receive the respective
ligaments 94, 96, 98 in the U-shaped slots 415. In general, the
mating features 402, 404, 406 are configured to conform, receive,
nest, or engage soft tissue.
[0050] The tibial guide 400 can be provided in various fitment
options depending on the desired stability of the tibial guide 400
on the tibia 92. Each fitment option can include a portion that
mates with the ACL 96, which provides a landmark for rotational
stability and unique positioning on the tibia 92. To additionally
improve stability, each fitment option can also include a portion
that mates with the MCL 94. To additionally improve stability, each
fitment option can also include a portion that mates with the LCL
98. Additionally, the patient-specific body 408 of the tibial guide
400 can comprise a bone engaging surface 413 that is a negative or
mirror image of boney and/or articular landmarks in the tibia 92.
Accordingly, the body 408 of the tibial guide 400 can nest on the
tibia to impart greater stability. Each fitment option allows the
tibial guide 400 to have a compact size, and include portions that
can fit over various anatomic landmarks in a unique position for
the patient. The particular fitment option can be selected for each
specific patient based on the patient's anatomy, the procedure to
be performed and the surgeon's preference and/or technique.
[0051] The patient-specific soft tissue mating portions 402, 404
(406) of the tibial guide 400 include a feature that is functional
to reversibly mate with soft tissue, such as a ligament. The
feature can be a hook, notch, slit, slot, or tab. As shown in
detail in FIG. 7, the mating features 402, 404, 406 can be slots
415 defined by two substantially parallel surfaces 409, 411 and a
stop 413 that form a U-shape. The mating features 402, 404, 406 are
designed by using a two-dimensional X-ray of the tibia 92 or by
using a three-dimensional image or model of the tibia 92, and
surrounding soft tissues of the specific patient generated by CT or
MRI scans. Mating the tibial guide 400 to the ACL 96, MCL 94, and
optionally to the LCL 98 enables the tibial guide 400 to be
oriented in a unique position on the proximal end 90 of the tibia
92. The tibial guide 400 can be designed to have a generally small
thickness, such that it can form a lightweight three-dimensional
shell from which the guiding elements 414, 416, 422, 424 extend
opposite to the anterior and superior faces 410, 412 of the tibia
62. The guiding elements 414, 416, 422, 424 can be formed to be
monolithic or integral portions of the tibial guide 400.
Alternatively, the guiding elements 414, 416, 422, 424 can be
modularly and removably coupled to the tibial guide 400, using, for
example, a threaded connection, snap-on connectors, or other
removable attachments.
[0052] FIG. 8 is a representation of the patient-specific tibial
guide 400 positioned on a tibia 92 at the proximal end 90. Anterior
alignment pins 440, 442 are drilled through a drill guide 444,
through the anterior guiding or pilot elements 414, 416, and into
the tibia 92. Likewise, superior alignment pins 446, 448 are
drilled through a drill guide 450, through the superior guiding or
pilot elements 422. 424, and into the superior face 412 of the
tibia 92. Because the locations of the guiding or pilot elements
414, 416, 422, 424 are predetermined during the preoperational
planning stage, they can be used to guide instruments to exact
locations relative to the tibia 92.
[0053] FIG. 9 is a representation of the tibia 92 with the
patient-specific tibial guide 400 and superior alignment pins 446,
448 removed. Pilot holes 452, 454 remain where the superior
alignment pins 446, 448 were removed. The anterior alignment pins
440,442 remain inserted in the anterior face 410 of the tibia 92.
As shown in FIG. 10, a tibial cut block 460 can be positioned
adjacent to the anterior surface 410 of the tibia 92 by positioning
the cut block 460 along the anterior alignment pins 440, 442. A
resecting tool 462 can then be inserted through a guide slit 464 in
the cut block 460 for resecting the proximal end 90 of the tibia 92
at a predetermined location.
[0054] FIG. 11 shows the tibia 92 with the superior alignment pins
446, 448 reinserted into the pilot holes 452, 454 shown in FIG. 8.
The anterior alignment pins 440, 442 have been removed. A trial
plate 460 is placed adjacent to a resected superior face 412' of
the tibia 92 by positioning the trial plate 460 along the superior
alignment pins 440, 442. An alignment instrument 472 comprising a
handle with an aperture 474 is placed along the superior alignment
pins 440, 442, and adjacent to the trial plate 460. An alignment
rod 476 is inserted through the aperture 474, which can be
visualized with reference to the tibia 92 to ensure proper
alignment. The alignment instrument 472, trial plate 470, and
superior alignment pins 446, 448 can then be removed, and a tibial
implant implanted adjacent to the superior face 412' of the tibia
92. Additional embodiments and a more detailed discussion on the
use of the guide bores and pins can be found in U.S. Patent
Publication No. 20120316564, published on Dec. 13, 2012, which is
incorporated herein by reference.
[0055] The present teachings also provide a method of manufacturing
a guide tool for guiding an instrument to a bone. The method
comprises obtaining at least one image of at least a portion of the
bone and optionally of a soft tissue at or near the bone; and
generating a two-dimensional or three-dimensional model of the bone
and soft tissue. The image can be a MRI or CT scan, ultrasound or
X-ray. Three-dimensional models can be generated from MRI and CT
scans, which include boney and soft tissue structures. X-ray images
can also be used to generate a model of bone. The approximate
location of ligaments at or near the bone can be determined based
on the location of ligaments in a typical patient. The bone can be
any bone in the human body. The soft tissue can be a ligament,
tendon, muscle, fibrous tissue or fat. The method further comprises
fabricating a patient-specific guide tool having a body portion and
a patient-specific portion. The body portion includes a guide
feature, and the patient-specific portion includes at least one
mating feature that is configured to conform to or engage the soft
tissue according to the two-dimensional or three-dimensional model.
Fabricating can be performed by any method known in the art.
[0056] The foregoing description of the embodiments has been
provided for purposes of illustration and description. It is not
intended to be exhaustive or to limit the disclosure. Individual
elements or features of a particular embodiment are generally not
limited to that particular embodiment, but, where applicable, are
interchangeable and can be used in a selected embodiment, even if
not specifically shown or described. The same may also be varied in
many ways. Such variations are not to be regarded as a departure
from the disclosure, and all such modifications are intended to be
included within the scope of the disclosure.
* * * * *