U.S. patent application number 14/946356 was filed with the patent office on 2016-03-17 for cross pin fixator for bone fragments and use thereof.
The applicant listed for this patent is A.M. SURGICAL, INC.. Invention is credited to Ather Mirza, Romi MIRZA.
Application Number | 20160074080 14/946356 |
Document ID | / |
Family ID | 48780485 |
Filed Date | 2016-03-17 |
United States Patent
Application |
20160074080 |
Kind Code |
A1 |
MIRZA; Romi ; et
al. |
March 17, 2016 |
CROSS PIN FIXATOR FOR BONE FRAGMENTS AND USE THEREOF
Abstract
The present application relates to a cross pin fixator device
comprising a plate member with spherical cavities that are open to
the front and to the back of the plate, collapsible pin holder
members having a central channel for insertion of a bone pin, the
collapsible pin holder member being press-fit into the spherical
cavities, and bone pins individually inserted into the central
channel of a pin holder. The application also relates to a method
for treating a fracture of the proximal humerus using the proximal
humerus cross pin fixator and to a kit for treating a fracture of a
bone.
Inventors: |
MIRZA; Romi; (Smithtown,
NY) ; Mirza; Ather; (Smithtown, NY) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
A.M. SURGICAL, INC. |
Smithtown |
NY |
US |
|
|
Family ID: |
48780485 |
Appl. No.: |
14/946356 |
Filed: |
November 19, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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14457756 |
Aug 12, 2014 |
9220550 |
|
|
14946356 |
|
|
|
|
13350561 |
Jan 13, 2012 |
8852248 |
|
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14457756 |
|
|
|
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Current U.S.
Class: |
606/290 |
Current CPC
Class: |
A61B 17/8061 20130101;
A61B 17/8047 20130101; A61B 17/8057 20130101; A61B 17/86 20130101;
A61B 17/88 20130101; A61B 17/8052 20130101; A61B 17/848
20130101 |
International
Class: |
A61B 17/80 20060101
A61B017/80; A61B 17/86 20060101 A61B017/86; A61B 17/84 20060101
A61B017/84 |
Claims
1. A cross pin fixator device comprising: a plate member having a
plurality of spherical cavities that are open to the front and to
the back of the plate; a plurality of collapsible pin holder
members having a central channel for insertion of a bone pin,
wherein each collapsible pin holder member is press-fit into one of
the spherical cavities, wherein at least one of the plurality of
collapsible pin holders is configured to freely rotate inside a
spherical cavity; and threaded holes in the plate comprising set
screws that contact the collapsible pin holder members from the
side and immobilize or deform the pin holder members in the
cavities.
2. The cross pin fixator device of claim 1, wherein the device is a
proximal humerus cross pin fixator.
3. The cross pin fixator device of claim 1, wherein the pin holders
are retained in the plate by ridges in the plate.
4. The cross pin fixator device of claim 1, wherein the plate is
constituted of a lightweight material.
5. The cross pin fixator device of claim 4, wherein the lightweight
material is selected from the group consisting of aluminum,
aluminum alloy, titanium, titanium alloy and a fiber reinforced
polymeric material.
6. The cross pin fixator device of claim 5, wherein the polymeric
material is selected from the group consisting of PPS
(polyphenylene sulfide), PEEK (polyetherether ketone), Ultrapek
(polyether ketone ether ketone), epoxy, polyester, polyamide, and
vinyl ester.
7. The cross pin fixator device of claim 5, wherein the fiber is
selected from the group consisting of carbon fibers, glass fibers,
metal fibers, synthetic fibers, and mixtures thereof.
8. The cross pin fixator device of claim 5, wherein the fiber
reinforced polymeric material comprises carbon-fiber reinforced
plastic.
9. The cross pin fixator device of claim 1, wherein the plate is
constituted of a high strength material.
10. The cross pin fixator device of claim 9, wherein the high
strength material is mineral reinforced plastic.
11. The cross pin fixator device of claim 10, wherein the mineral
is selected from the group consisting of talc, silica, silicon
carbide, zirconia and alumina.
12. The cross pin fixator device of claim 9, wherein the high
strength material is a ceramic material.
13. The cross pin fixator device of claim 12, wherein the ceramic
material is selected from the group consisting of alumina,
zirconia, and silicon carbide.
14. The cross pin fixator device of claim 9, wherein the high
strength material is steel or steel alloys.
15-17. (canceled)
18. A method for treating a fracture of a proximal humerus in a
patient comprising: inserting one end of each of a plurality of
bone pins through the fracture site, wherein the bone pins traverse
the site of the bone fracture in a multi-angle and multi-planar
configuration so as to secure fractured bone segments against
rotation and axial movement, and inserting the opposite end of each
of the plurality of bone pins through a collapsible pin holder
member of a proximal humerus cross pin fixator having a central
channel for insertion of a bone pin, wherein each collapsible pin
holder member is press-fit into a spherical cavity of a plate
member of the proximal humerus cross pin fixator and wherein at
least one of the plurality of collapsible pin holders is configured
to freely rotate inside a spherical cavity.
19. The method of claim 18, wherein each bone pin is a Kirschner
wire.
20. The method of claim 18, further comprising immobilizing or
deforming a collapsible pin holder by tightening a set screw
inserted into a threaded hole in the plate member of the proximal
humerus cross pin fixator.
21. A kit for the treatment of a fracture of a bone, comprising:
the cross pin fixator device of claim 1, and a plurality of bone
pins.
22. The kit of claim 21, wherein the bone pins are Kirschner wires.
Description
[0001] This application is a Continuation of U.S. application Ser.
No. 14/457,756, filed on Aug. 12, 2014 which is a Continuation of
U.S. application Ser. No. 13/350,561, filed on Jan. 13, 2012, now
U.S. Pat. No. 8,852,248. The entirety of the aforementioned
applications is incorporated herein by reference.
FIELD
[0002] This application generally relates to medical devices. In
particular, the application relates to a medical device for
immobilizing bone fragments of a fractured bone, such as a
fractured proximal humerus.
BACKGROUND
[0003] Bone fractures are typically treated by restoring the
fractured pieces of bone to their natural positions and maintaining
those positions while the bone heals. Briefly, the fractured
bone(s) is aligned in good position (also called reduction) and
then immobilized with a cast that holds the bones in position and
immobilizes the joints above and below the fracture. When the
initial post-fracture edema or swelling goes down, the fracture may
be placed in a removable brace or orthosis. In cases of complex or
open fractures, surgical nails, screws, plates and wires may be
used to internally hold the fractured bone together. The surgical
implantation of these internal fixation devices, however, may cause
extensive trauma to the patient, increase potential for infection,
and require second surgery for their removal. An alternative to
internal fixation devices is the external fixation device. Pins are
placed into the broken bone above and below the fracture site to
reposition and immobilize the bone fragments. The pins are
connected to a metal bar or bars outside the skin to form a
stabilizing frame that holds the bones in the proper position so
they can heal. After an appropriate period of time, the external
fixation device is removed.
[0004] The proximal humerus is part of the shoulder joint, and it
also is the attachment of the important rotator cuff muscles. These
muscles help with movement of the shoulder, and injury to the
proximal humerus can affect the function of these muscles. A
proximal humerus fracture is a common injury to the shoulder and
are among the most common broken bones. It is not possible to
immobilize proximal humerus fractures by placing them in a cast.
There still exists a need for lightweight, non-bridging external
fixation devices that allows for direct fixation of a proximal
humerus fracture, maintenance of the radiological parameters, and
early mobilization of the shoulder.
SUMMARY
[0005] One aspect of the present application relates to a cross pin
fixator device comprising: a plate member having a plurality of
spherical cavities that are open to the front and to the back of
the plate, a plurality of collapsible pin holder members having a
central channel for insertion of a bone pin, wherein each
collapsible pin holder member is press-fit into one of the
spherical cavities, threaded holes in the plate comprising set
screws that immobilize or deform the pin holder members in the
cavities, and a plurality of bone pins, wherein each bone pin is
inserted into the central channel of a pin holder.
[0006] Another aspect of the present application relates to a
collapsible, spherical pin holder comprising: a central channel
open at the top and the bottom of the pin holder, and a compression
gap in the side of the pin holder, wherein the compression gap is
parallel to and connected with the central channel.
[0007] Another aspect of the present application relates to a
method for treating a fracture of a proximal humerus in a patient
comprising: inserting one end of each of a plurality of bone pins
through the fracture site, wherein the bone pins traverse the site
of the bone fracture in a multi-angle and multi-planar
configuration so as to secure fractured bone segments against
rotation and axial movement, and inserting the opposite end of each
of the plurality of bone pins through a collapsible pin holder
member of a proximal humerus cross pin fixator having a central
channel for insertion of a bone pin, wherein each collapsible pin
holder member is press-fit into a spherical cavity of a plate
member of the proximal humerus cross pin fixator.
[0008] Another aspect of the present application relates to a kit
for the treatment of a fracture of a bone comprising: a plate
member of a cross pin fixator device having a plurality of
spherical cavities that are open to the front and to the back of
the plate, the plate member further having a plurality of threaded
holes in the plate for set screws, a plurality of collapsible pin
holder members having a central channel for insertion of a bone
pin, wherein each collapsible pin holder member can be press-fit
into one of the spherical cavities of the plate member, and a
plurality of bone pins.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The accompanying drawings illustrate one or more embodiments
of the application and, together with the written description,
serve to explain the principles of the application. Wherever
possible, the same reference numbers are used throughout the
drawings to refer to the same or like elements of an
embodiment.
[0010] FIGS. 1A-E show different views of an exemplary proximal
humerus cross pin fixator.
[0011] FIGS. 2 A-H show different views of the plate member of the
exemplary proximal humerus cross pin fixator.
[0012] FIGS. 3A-F show views of a pin holder member of the
exemplary proximal humerus cross pin fixator.
DETAILED DESCRIPTION
[0013] The following detailed description is presented to enable
any person skilled in the art to make and use the invention. For
purposes of explanation, specific nomenclature is set forth to
provide a thorough understanding of the present invention. However,
it will be apparent to one skilled in the art that these specific
details are not required to practice the invention. Descriptions of
specific applications are provided only as representative examples.
The present invention is not intended to be limited to the
embodiments shown, but is to be accorded the widest possible scope
consistent with the principles and features disclosed herein.
[0014] The present application relates to an external fixation
device for the immobilization of bone fragments of fractured bones.
In a preferred embodiment, the external fixation device is a cross
pin fixator. In some particular embodiments, the fracture is a
simple fracture. In some particular embodiments, the fracture is
comminuted. In some particular embodiments, the fracture is
displaced. In some particular embodiments, the fracture is
non-displaced.
[0015] One aspect of the present application relates to a cross pin
fixator device comprising: a plate member having a plurality of
spherical cavities that are open to the front and to the back of
the plate, a plurality of collapsible pin holder members having a
central channel for insertion of a bone pin, wherein each
collapsible pin holder member is press-fit into one of the
spherical cavities, threaded holes in the plate comprising set
screws that contact the collapsible pin holder members from the
side and immobilize or deform the pin holder members in the
cavities, and a plurality of bone pins, wherein each bone pin is
inserted into the central channel of a pin holder.
[0016] In one particular embodiment, the cross pin fixator device
is a proximal humerus cross pin fixator.
[0017] In a particular embodiment, the pin holders are retained in
the plate by ridges in the plate.
[0018] In another particular embodiment, the plate is constituted
of a lightweight material. In a related embodiment, the lightweight
material is selected from the group consisting of aluminum,
aluminum alloy, titanium, titanium alloy and a fiber reinforced
polymeric material.
[0019] In a further embodiment, the polymeric material is selected
from the group consisting of PPS (polyphenylene sulfide), PEEK
(polyetherether ketone), Ultrapek (polyether ketone ether ketone),
epoxy, polyester, polyamide, and vinyl ester.
[0020] In another further embodiment, the fiber is selected from
the group consisting of carbon fibers, glass fibers, metal fibers,
synthetic fibers, and mixtures thereof.
[0021] In another further embodiment, the fiber reinforced
polymeric material comprises carbon-fiber reinforced plastic.
[0022] In another particular embodiment, the plate is constituted
of a high strength material.
[0023] In a further embodiment, the high strength material is
mineral reinforced plastic. In a related embodiment, the mineral is
selected from the group consisting of talc, silica, silicon
carbide, zirconia and alumina.
[0024] In another further embodiment, the high strength material is
a ceramic material. In a related embodiment, the ceramic material
is selected from the group consisting of alumina, zirconia, and
silicon carbide.
[0025] In another further embodiment, the high strength material is
steel or steel alloys.
[0026] Another aspect of the present application relates to a
collapsible, spherical pin holder comprising: a central channel
open at the top and the bottom of the pin holder, and a compression
gap in the side of the pin holder, wherein the compression gap is
parallel to and connected with the central channel.
[0027] In a particular embodiment, the spherical pin holder further
comprises a slit in the side opposite the compression gap, wherein
the slit is parallel to but is not connected with the central
channel.
[0028] In another embodiment, the spherical pin holder is
constituted of polyphenylsulfone.
[0029] Another aspect of the present application relates to a
method for treating a fracture of a proximal humerus in a patient
comprising: inserting one end of each of a plurality of bone pins
through the fracture site, wherein the bone pins traverse the site
of the bone fracture in a multi-angle and multi-planar
configuration so as to secure fractured bone segments against
rotation and axial movement, and inserting the opposite end of each
of the plurality of bone pins through a collapsible pin holder
member of a proximal humerus cross pin fixator having a central
channel for insertion of a bone pin, wherein each collapsible pin
holder member is press-fit into a spherical cavity of a plate
member of the proximal humerus cross pin fixator.
[0030] In a particular embodiment, each bone pin is a Kirschner
wire.
[0031] In another particular embodiment, the method further
comprises immobilizing or deforming a collapsible pin holder by
tightening a set screw inserted into a threaded hole in the plate
member of the proximal humerus cross pin fixator.
[0032] Another aspect of the present application relates to a kit
for the treatment of a fracture of a bone comprising: a plate
member of a cross pin fixator device having a plurality of
spherical cavities that are open to the front and to the back of
the plate, the plate member further having a plurality of threaded
holes in the plate for set screws, a plurality of collapsible pin
holder members having a central channel for insertion of a bone
pin, wherein each collapsible pin holder member can be press-fit
into one of the spherical cavities of the plate member, and a
plurality of bone pins.
[0033] The cross pin fixator device of the present application can
be adapted to a shape and size to immobilize fragments of any
fractured bone in a mammalian body. In a particular embodiment,
said mammal is a human.
[0034] In particular embodiments, the bone is a long bone, having a
shaft and two extremities. Long bones are found in the limbs and
include the clavicle, humerus, radius, ulna, femur, tibia, fibula,
metacarpal and metatarsal bones.
[0035] As used herein, the "proximal" end of a long bone refers to
the extremity of the bone closest to the center of the body when
the limb is extended. As used herein, the "distal" end of a long
bone refers to the extremity of the bone farthest from the center
of the body when the limb is extended. The cross pin fixator device
of the present application may be specifically configured to
immobilize the fragments of a fracture at the proximal end of a
long bone, the distal end of a long bone, or the shaft of a long
bone, or a combination thereof. In some embodiments, the cross pin
fixator device may span across a joint between two long bones,
immobilizing the fragments of the fractured distal end of one long
bone and the fragments of the fractured proximal end of an adjacent
long bone.
[0036] In other particular embodiments, the cross pin fixator
device of the present application can be configured to immobilize
the fragments of a fractured short bone, including the patella,
sesamoid, carpal and tarsal bones.
[0037] In further particular embodiments, the cross pin fixator
device of the present application can be configured to immobilize
the fragments of a fractured flat bone, including the skull,
cranium, occipital, parietal, frontal, nasal, lachrymal, vomer,
scapula, os innominatum, sternum, and rib bones.
[0038] In additional particular embodiments, the cross pin fixator
device of the present application can be configured to immobilize
the fragments of a fractured irregular bone, including the
vertebrae, sacrum, coccyx, temporal, sphenoid, ethmoid, malar,
superior maxillary, inferior maxillary, palate, inferior
turbinated, and hyoid bones. In particular embodiments, the cross
pin fixator device spans across multiple vertebrae, including any
portion of the vertebral column, the cervical vertebrae, and/or the
dorsal vertebrae, and/or the lumbar vertebrae, and/or the sacral
vertebrae, and/or the coccygeal vertebrae or the entire vertebral
column.
[0039] In some embodiments, the cross pin fixator device of the
present application may span across between any two or more
adjacent bones, immobilizing the fragments of the fractured bones.
In particular embodiments, the cross pin fixator device of the
present application may span across between any two, three, four,
five, six, seven, eight, nine, 10, 11, 12, 13, 14, 15, 16, 16, 18,
19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32 or 33
adjacent bones, immobilizing the fragments. In some embodiments,
the bones are adjacent linearly, such as the vertebrae. In some
embodiments, the bones are adjacent side by side, such as the
metacarpals or metatarsals.
[0040] In some embodiments, one region of the cross pin fixator
device of the present application is attached to at least one
non-fractured bone in order to provide stability to immobilized
fragments of a fractured adjacent bone attached to another region
of the cross pin fixator device.
[0041] For purposes of describing the cross pin fixator device of
the present application, a proximal humerus cross pin fixator is
exemplified and the following terms are used:
[0042] As used herein, the "top" refers to the end of the device
that is oriented towards the ball or head of the humerus.
[0043] As used herein, the "bottom" refers to the end of the device
that is oriented towards the shaft of the humerus.
[0044] As used herein, the "inside" or "back" refers to the face of
the device that is oriented towards the body of the patient.
[0045] As used herein, the "outside" or "front" refers to the face
of the device that is oriented away from the body of the
patient.
[0046] As used herein, the "side" refers to surfaces around the
perimeter of the device joining the outside face to the inside
face.
[0047] In some embodiments, the proximal humerus cross pin fixator
device is indicated for simple and comminuted, displaced and/or
non-displaced fractures of the proximal humerus.
[0048] FIG. 1A shows a face of the plate 1 comprising a plurality
of collapsible pin holders 2 that are individually press-fit into
individual cavities 3 in the plate 1. The cavities 3 are open to
the inside and outside faces of the plate 1 and each pin holder 2
can freely rotate inside the cavity 3.
[0049] FIG. 1B shows a cross section of the device along the line
A-A' in FIG. 1A. Pin holders 2 can be seen located in cavities 3 in
the plate 1. Each pin holder 2 can be seen to be spherical in shape
and comprises a central channel for the insertion of a bone pin or
screw. Each bone pin is driven into a bone fragment and threaded
though an individual pin holder 2 of the device. Each cavity 3 is
also spherical in shape to allow the pin holder 2 to freely rotate
within the cavity 3. Additionally, each cavity 3 comprises ridges
at the inside and outside faces of the plate 1 to hold the
collapsible spherical pin holder 2 in the cavity 3 after it is
press-fit into said cavity 3.
[0050] Additionally in FIG. 1B, a set screw 4 is shown in a
threaded hole 5 that contacts a cavity 3. Each threaded hole 5 is
located open at one end to the side of the device and at the other
end to a cavity 3. The set screw 4 is screwed into the threaded
hole 5 in order to contact the collapsible pin holder 2 from the
side. The contact of the set screw 4 with the pin holder 2
immobilizes the pin holder in the cavity 3 from the side and
deforms the pin holder 2 such that a pin that is secured into a
bone fragment is held in place by the device. In a particular
embodiment, each cavity 3 is contiguous with at least one threaded
hole 5 and at least one set screw 4 is used to immobilize or deform
each collapsible pin holder 2 from the side.
[0051] FIGS. 1C and 1D depict side aspect views between the top and
bottom of the device showing the plate 1 along with set screws 4
and threaded holes 5. In a particular embodiment, the set screw 4
is completely recessed within the threaded hole 5. In another
embodiment, the head of the set screw 4 protrudes from the threaded
hole 5. In a particular embodiment, the head of the set screw 4 is
adapted to be driven with a screwdriver or bit selected from the
group consisting of flat-bladed, triangular, square, Philips, hex,
TORX, or star-shaped.
[0052] FIG. 1E is an end view of the device from the bottom side
showing the plate 1. In a particular embodiment, the plate 1 is
curved such that the inside face is concave and the outside face is
convex. In another embodiment, the plate 1 is flat. In another
embodiment, the edges of the plate 1 or at least a portion thereof
is angled towards the inside of the device.
[0053] In addition, the proximal humerus cross pin fixator of the
present application uses small diameter bone pins that flex and
allow lead sharing across the fracture fragments, facilitating
callus formation and reducing the risk of nonunion. Also, the cross
positioning of bone pins fixes the larger fracture fragments while
buttressing the smaller fragments, helping to maintain joint
congruency.
[0054] In a particular embodiment, the bone pin is constituted of a
surgical grade metal. In another particular embodiment, the bone
pin is a Kirschner wire (K-wire). In a further embodiment, the
K-wire is between about 1 mm and about 6 mm in diameter. In a still
further embodiment, the K-wire is between about 3 mm and about 5 mm
in diameter. In a yet further embodiment, the K-wire is about 4 mm
in diameter.
[0055] FIGS. 2A-H show aspect views of the plate 1 of the external
proximal humerus cross pin fixator. FIG. 2A shows a face of the
plate 1 member, having a plurality of cavities 3 for the placement
of pin holders. In a particular embodiment, the plate is made of a
lightweight material. In a further embodiment, the lightweight
material is aluminum or an aluminum alloy. In another further
embodiment, the lightweight material is titanium or a titanium
alloy.
[0056] In another further embodiment, the lightweight material is a
fiber reinforced lightweight polymeric material.
[0057] In one embodiment, the polymeric material is selected from
the group consisting of PPS (polyphenylene sulfide), PEEK
(polyetherether ketone), Ultrapek (polyether ketone ether ketone),
epoxy, polyester, polyamide, and vinyl ester.
[0058] In another embodiment, the fiber is selected from the group
consisting of carbon fibers, glass fibers, metal fibers, synthetic
fibers, and mixtures thereof.
[0059] In another embodiment, the fiber reinforced polymeric
material is a carbon-fiber reinforced plastic.
[0060] In a related embodiment, the carbon-fiber reinforced plastic
has a minimal tensile strength equal to or greater than 30 Ksi.
[0061] In another related embodiment, the carbon-fiber reinforced
plastic is PPS reinforced with 40-60% of carbon fiber.
[0062] In another related embodiment, the carbon-fiber reinforced
plastic is PEEK reinforced with 30-50% of carbon fiber.
[0063] In another related embodiment, the carbon-fiber reinforced
plastic is epoxy reinforced with 30-60% of carbon fiber.
[0064] In another particular embodiment, the plate is made from a
high strength material.
[0065] In a further embodiment, the high strength material is
mineral reinforced plastic. In a related embodiment, the mineral is
selected from the group consisting of talc, silica, silicon
carbide, zirconia and alumina.
[0066] In another further embodiment, the high strength material is
a ceramic material. In a related embodiment, the ceramic material
is selected from the group consisting of alumina, zirconia, and
silicon carbide.
[0067] In another further embodiment, the said high strength
material is steel or steel alloys.
[0068] FIG. 2B shows an end-view of the top side of the plate 1
having threaded holes 5 for the insertion of set screws.
[0069] FIGS. 2C and 2D show side views between the top and bottom
of the plate 1 having threaded holes 5 for the insertion of set
screws.
[0070] FIG. 2E shows a cross section of the device along the line
A-A' in FIG. 2A. The spherically shaped cavities 3 can be seen in
the plate 1. Each cavity 3 comprises ridges at the inside and
outside faces of the plate 1 to hold the collapsible spherical pin
holder in the cavity 3 after it is press-fit into said cavity 3.
The threaded holes 5 for the insertion of set screws are shown to
be contiguous with the cavities 3 so that the set screws can
contact the spherical pin holders for immobilization or
deforming.
[0071] FIG. 2F shows a cross section of the device along the line
B-B' in FIG. 2A. The spherically shaped cavities 3 can be seen in
the plate 1. Each cavity 3 comprises ridges at the inside and
outside faces of the plate 1 to hold the collapsible spherical pin
holder in the cavity 3 after it is press-fit into said cavity
3.
[0072] FIGS. 2G and 2 H are perspective views of the plate 1
showing the inside and outside faces, respectively.
[0073] FIGS. 3A-F are views of the collapsible spherical pin holder
2 member of the device. FIG. 3A is a view from the top of a
collapsible spherical pin holder 2 member of the device. The pin
holder comprises a central channel 6 for the insertion of a bone
pin or screw. The bone pin is embedded in a fragment of the
fractured bone and is threaded through the central channel 6 of the
pin holder 2 in order to secure the bone pin to the proximal
humerus cross pin fixator. In a particular embodiment, the pin
holder 2 comprises a compression gap 7 in the side of the sphere
that is contiguous with the central channel 6 in order to allow
compression of the sphere. In a related embodiment, the compression
gap 7 is wedge-shaped. In a further embodiment, the angle of the
wedge is between about 20 degrees and about 60 degrees. In a still
further embodiment, the angle of the wedge is between about 30
degrees and about 50 degrees. In a still further embodiment, the
angle of the wedge is between about 35 degrees and about 45
degrees. In a still further embodiment, the angle of the wedge is
about 40 degrees.
[0074] Still referring to FIG. 3A, in some embodiments, the pin
holder 2 further comprises a slit 9 in the side of the pin holder 2
opposite of the compression gap 7. The slit 9 does not penetrate
through the body of the pin holder 2.
[0075] In a particular embodiment, the top and bottom ends of the
central channel 6 are beveled 10 to ease the threading of the bone
pin into the pin holder 2.
[0076] In a particular embodiment, the pin holders are made of
polyphenylsulfone. [Dr. Mirza: are there any other materials that
should be listed here for the pin holders?]
[0077] FIG. 3B shows a side view of a pin holder 2 of the device.
The dashed lines indicated the relative positions of the central
channel 6, slit 9, and beveling 10 within the body of the pin
holder 2.
[0078] FIG. 3C shows a frontal view of a pin holder 2 of the
device. The drawing shows the central channel 6 and the bevels 10
at the top and bottom of the central channel 6 as viewed through
the compression gap 7.
[0079] FIG. 3D shows a cross section of a pin holder 2 along the
line C-C' in FIG. 3B. The drawing shows the central channel 6 and
the bevels 10 at the top and bottom of the central channel 6. The
dashed lines indicated the relative position of the slit 9 within
the body of the pin holder 2 behind the central channel 6.
[0080] FIGS. 3E and 3F are perspective views generally showing the
front and back, respectively, of a pin holder 2.
[0081] Another aspect of the present application relates to a
method for the treatment of a fracture of the proximal humerus. The
method comprises embedding bone pins into fragments of the
fractured proximal humerus and threading the bone pins through
collapsible pin holders in a proximal humerus cross pin fixator as
described herein. The rotational position of each collapsible pin
holder is secured in the device and the bone pin is immobilized in
the collapsible pin holder by tightening a set screw against the
side of the collapsible pin holder.
[0082] In some embodiments, the length of a bone pin protruding
from the outside face of the device is trimmed or cut flush with
the outside face after the bone pin is immobilized in the
collapsible pin holder.
[0083] Another aspect of the present application relates to a kit
for the treatment of a fracture of the proximal humerus comprising:
a plate member of a proximal humerus cross pin fixator having a
plurality of spherical cavities that are open to the front and to
the back of the plate, the plate member further having a plurality
of threaded holes in the plate for set screws, a plurality of
collapsible pin holder members having a central channel for
insertion of a bone pin, wherein each collapsible pin holder member
can be press-fit into one of the spherical cavities of the plate
member, and a plurality of bone pins.
[0084] In a particular embodiment, the kit further includes a
tissue protector. In another particular embodiment, the kit
comprises a tool for tightening the set screws.
[0085] The contents of all references, patents and published patent
applications cited throughout this application, as well as the
Figures and Tables, are incorporated herein by reference.
[0086] The above description is for the purpose of teaching the
person of ordinary skill in the art how to practice the present
invention, and it is not intended to detail all those obvious
modifications and variations of it which will become apparent to
the skilled worker upon reading the description. It is intended,
however, that all such obvious modifications and variations be
included within the scope of the present invention, which is
defined by the following claims. The claims are intended to cover
the components and steps in any sequence which is effective to meet
the objectives there intended, unless the context specifically
indicates the contrary.
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