Invention (Patent): Shah MK. Joint replacement system, US6010535 (2000).
US6010535A United States
Inventor: Mrugesh K. Shah
Current Assignee: Individual
Worldwide applications 1998 US
Application US09/070,205 events:
1998-04-30 Application filed by Individual
1998-04-30 Priority to US09/070,205
2000-01-04 Application granted
2000-01-04 Publication of US6010535A
2018-04-30 Anticipated expiration
Status: Expired - Fee Related
Joint replacement system
Mrugesh K. Shah
Abstract
A
replacement system for a joint including a first cup member having an interior
lining material and forming a hemispherical cavity therein, a ball member
received within the hemispherical cavity and being cantable within the cavity,
a securing member connected to the first cup member for affixing the first cup
member within an acetabulum area of the pelvic bone of a human joint, and an
affixing member interconnected to the ball member for affixing the ball member
against the femoral head area of the femur of a human joint. The ball has an
outer diameter of no more than one inch. The securing member is a screw having
one end embedded into the first cup member and extending through the pelvic bone.
The affixing member is a shaft connected at one end to the ball member and
extends into the femur bone. The affixing member further includes a nail
extending through a portion of the femur and engaged with the shaft distal the
ball member. This nail is secured to the femur through the use of surgical
screws.
Description
TECHNICAL FIELD
The present
invention relates to various medical devices used for the replacement of human
joints. More particularly, the present invention relates to methods and
apparatus for replacing human joints, in particular, hip joints.
BACKGROUND ART
Prostheses for the
replacement of hip joints are already known. Originally, only the ball-end on
the head of the femur could be replaced, but it has since proved possible to
replace either part of the hip joint, that is to say, the acetabulum or the
ball-end on the head of the femur.
The number of those
living with hip prostheses is increasing more and more at the present time. The
number of implanted artificial hip joints is estimated to be two thousand per
day. The further increase of the cases into the millions is accounted for by
the fact that the diseases of the hip joints due to wear are increasing
numerically along with the rapid rise of the age of the population accompanied
by a corresponding development of the medical technique.
Existing techniques
for the carrying out of the hip replacement operation are extremely invasive.
As such, the patient will require long periods of rehabilitation and long
periods of hospital stay. Since a great deal of biological material is removed
or replaced in the patient, a great amount of time is required for healing.
Furthermore, the operative procedures are very time-consuming and very
expensive.
Existing hip
replacement techniques initially require the exposure of the femur. The hip
must be dislocated so that the level of the neck resection can be measured
proximally from the lesser femoral head based on the preoperatively templated
measurement. In addition, the center of the femoral head is approximated and
marked. A right angle retractor is used to judge the anatomical relationship
for the later restoration of leg length and offset. The femoral neck cut is
made by using a femoral broach as a template, by using the femoral neck cutting
guide, or by using a femoral resection template. The neck cut is made slightly
horizontal, which allows the use of the calcar planer to obtain a smooth
surface for eventual flush collar-calcar seating.
Following the
removal of the femoral head, a partial superior and anterior capsulectomy is
performed to allow exposure of the anterior acetabular rim. Hohmann or similar
retractors are placed over the anterior rim for retraction of the shaft
anteriorly. Posterior and superior Charnley pin retractors are placed in the
interval between the capsule and the labrum to allow complete exposure. The
acetabular rim is then completely exposed by thorough removal of the acetabular
labrum.
Once acetabular
exposure has been accomplished, reaming is initiated. Reaming continues until
concentric removal of all remaining acetabular cartilage and the exposure of
punctate bleeding in the subchondral plate is achieved. The medial landmark for
correct depth is the acetabular floor visualized through the acetabular fossa.
A cup sizer corresponding to the last reamer used is placed on a handle and
inserted into the acetabulum. The acetabular cup sizers are the same size as
the actual implant and should fit snugly into the acetabulum.
It is then
necessary to insert the cup. To correctly judge the appropriate component
position, a down-sized acetabular sizer can be easily inserted and positioned
into the acetabulum so as to allow removal of any overhanging anterior,
posterior or superior osteophytes. Once these steps have been completed, the
correct acetabular shell is locked into the acetabular positioner and driven into
a fully seated position. Screws can then be used for supplemental fixation.
After the placement
of the acetabular component, attention is then turned to the femur. The femoral
canal is identified with a hand-held reamer. Power reaming is initiated with a
conical reamer. The reamer is advanced slowly within the canal until the
proximal cutting edge is at the level of the calcar. As the reamer is
withdrawn, lateral pressure is exerted to insure proper lateralization within
the canal. Reaming proceeds in one millimeter or two millimeter increments
depending on the bone density. Once the appropriate conical reamer has been
passed, rasping is initiated. The rasp should be oriented so that the
mediolateral axis of the rasp is parallel to the anatomic mediolateral axis of
the femoral neck. The rasp is impacted until it is slightly below the level of
the initial calcar cut. Subsequently, larger rasps are used until the final
rasping is completed with the appropriate size. With the proper size rasp in
place, the calcar is planed flush by using the calcar trimmer. With the final
rasp still in place, provisional heads/necks are selected to determine the
appropriate neck length in order to restore the lateral offset. Trial reduction
is carried out to assure that proper leg length and stability are achieved. The
stem corresponding to the size of the final rasp used is threaded onto the stem
inserter/extractor and impacted into a fully seated position. The collar should
seat flush against the medial calcar and the lateral shoulder should seat
against the femoral head. After filly seating the femoral component, the
appropriate modular head is impacted into the femoral neck. The hip is now
ready to be reduced.
As can be seen,
this procedure is quite invasive. A great deal of manipulation is required by
the surgeon so as to properly install the artificial hip. Under certain
circumstances, the patient does not fully recover from such invasive surgery. A
great deal of rehabilitation and recovery are required to filly recover from
such an invasive operation. As such, a need has developed so as to carry out a
less invasive technique for the installation of a hip replacement.
In the past,
various patents have issued relating to hip replacement operations and to hip
prostheses.
U.S. Pat. No.
3,748,662, issued on Jul. 31, 1973 to A. J. Helfet, describes a surgical
procedure for replacing the natural components of a bicondylar joint in a human
limb. The prosthetic implant has two pairs of coacting male and female condylar
components. The male and female components which replace the natural lateral
condyles are spherical or spheroidal in shape to simulate a ball and sock
joint. Both male components and both female components can be formed on
respective rigid carriers or they may optionally be separate for individual
fixation to the patient's limb.
U.S. Pat. No.
3,894,297, issued on Jul. 15, 1975 to Mittelmeier et al., describes a hip joint
prosthesis which comprises a substantially frustoconical acetabulum member
provided with supporting ribs in the form of a tapering thread and a prosthesis
shaft provided with circular supporting ribs allowing anchorage of the
prosthesis and the acetabulum member without using a cement or other adhesive.
U.S. Pat. No.
4,187,559, issued on Feb. 12, 1980 to Grell et al., describes a body joint
endoprosthesis including an anchoring member having a shaft anchored in a first
bone and a pivot member connected to the anchoring member by a pivot joint. The
pivot member includes a first body joint member and a support element that
bears against a seating surface of the first bone. The first body joint member
and the second body joint member are connected to the second bone so as to form
the body implant joint.
U.S. Pat. No.
4,355,427, issued on Oct. 26, 1982 to W. Schneider, describes an artificial
humerus head having a groove in its exterior surface for receiving the long
biceps tendon. A cover bridges the groove to form an elongated open-end channel
for the tendon and makes it possible to arrange the long biceps tendon in the
channel without separation thereof from the head.
U.S. Pat. No.
4,530,115, issued on Jul. 23, 1985 to Muller et al., describes a shank for a
prosthesis which is composed of a blade which carries a joint head and a
wedge-shaped end piece. The end piece is driven in along a guide in the lateral
narrow side of the blade while the blade remains in a fixed position. The
wedge-shaped form of the end piece permits fixation of the blade at a
predetermined height such that the joint head can be at the level of the
trochanter tip.
U.S. Pat. No.
4,775,381, issued on Oct. 4, 1988 to Tari et al., describes a hip prosthesis
formed with a conventional head provided with a spherical shape, a neck, and a
stem. A guide profile is formed along the outer straight side of the stem and
contains components which are parallel with the side. The guide profile fits
the inner surface of the medullary cavity nail so as to allow the simultaneous
use of the hip prosthesis and the medullary cavity nail and the nailing of the
already prosthetized femur.
U.S. Pat. No.
5,026,399, issued on Jun. 25, 1991 to Engelbrecht et al., describes a
prosthetic device for the partial or total replacement of a bone, such as a
femur. The prosthesis has a rod-like bridging member which spans the major part
of the gap between the two joints. An abutment member is mounted at either end
of the bridging member and each of the abutment members engages a bone adjacent
that which is to be partially or totally replaced. Each of the abutment members
may constitute part of an artificial joint. The abutment members may be
rotatable relative to one another and to the bridging member about the
longitudinal axis of the latter in order that the abutment members may assume a
relative angular orientation best suited to the characteristics of the patient.
U.S. Pat. No.
5,702,457, issued on Dec. 30, 1997 to Walsh et al., describes a humeral
prosthesis including a shank having a metaphyseal part having a housing therein
with a semi-spherical portion in which housing is introduced a sphere to which
is secured a bearing surface hemispherical cap adapted to be received within
the glenoid cavity of a shoulder. A securing element is provided which extends
through the metaphyseal part of the shank for securing the sphere within the
housing at a predetermined position with respect to the shank.
U.S. Pat. No.
5,725,597, issued on Mar. 10, 1998 to S. K. Hwang, describes an artificial hip
joint having a construction capable of reducing abrasion of a polyethylene
layer formed within the acetabulum cup when the head of the femur pivots in the
acetabulum cup. The artificial acetabulum cup is implanted in the acetabulum of
a user's pelvic bone and includes a hollow hemispherical member made of a
metal. The polyethylene layer is formed on the inner surface of the
hemispherical member. A femoral head holder is fixed to the femur. The femur
head holder includes a spherical metal femur head pivotally held in the
artificial acetabulum cup. A shaft is coupled at an upper end thereof to the femoral
head and adapted to support the femoral head. A housing extends inclinedly
through the greater trochanter of the femur and adapted to receive the shaft
therein in such a manner that it rotates with respect to the shaft. Bearings
are mounted between the shaft and the housing and are adapted to support
axially and radial loads applied to the shaft at the femur head by the weight
of the user.
It is an object of
the present invention to provide a joint replacement system which minimizes the
amount of invasive surgery.
It is another
object of the present invention to provide an artificial joint system which
minimizes rehabilitation and recovery time.
It is a further
object of the present invention to provide a joint replacement system which
minimizes the materials required for the joint replacement.
It is still another
object of the present invention to provide an artificial joint system which
simplifies surgical techniques for the installation of such a joint system.
It is another
object of the present invention to provide a process in which joint
replacements can be carried out on an outpatient basis.
It is still a
further object of the present invention to provide an artificial joint system
which is relatively inexpensive and reduces the cost of surgery.
It is another
object of the present invention to provide an artificial joint system which can
be installed with arthroscopic and fluoroscopic techniques.
The foregoing
disclosure and description of the invention is illustrative and explanatory
thereof. Various changes in the details of the illustrated construction may be
made within the scope of the appended claims without departing from the true
spirit of the invention.
SUMMARY OF THE INVENTION
The present
invention is a joint replacement system which includes a first cup member
having an interior lining material and forms a generally hemispherical cavity
therein such that the interior lining material surrounds the hemispherical
cavity, a ball member received within the hemispherical cavity so that the ball
member is cantable within the cavity, a securing member connected to the first
cup member for affixing the first cup member within a human bone adjacent to
one component of the joint, and an affixation member interconnected to the ball
member for affixing the ball member within another human bone adjacent another
component of the joint. The ball member has a diameter of no more than one
inch.
In the present
invention, the securing member includes at least one screw having one end
embedded in the first cup member. In the preferred embodiment of the present
invention the human bone is a pelvic bone. The affixation member is a shaft
which is affixed at one end to the ball member and extends into a femur bone.
This affixation member further includes a nail extending through a portion of
the femur bone so as to be engaged with the shaft distal the ball member. The
ball member will extend outwardly of a surface of the femur head. A spacer ring
may extend around the shaft so as to be interposed between the ball member and
another surface of the femur head.
In an alternative
embodiment of the present invention, a second cup member is provided so that
the ball member has a portion received within the second cup member. The first
cup member and the second cup member generally surround the ball member. The
affixation member is connected to the second cup member so as to secure the
second cup member and the ball member within another human bone. The affixation
member includes at least one screw having an end embedded in the second cup
member. The second cup member has an interior lining and has a generally
hemispherical cavity therein. The interior lining generally surrounds the
hemispherical cavity. The second ball member is received within the
hemispherical cavity of the second cup member and is cantable within the second
cup member. In another embodiment of the present invention, a rod has one end
connected to the first ball member and an opposite end connected to the second
ball member.
In a further
embodiment of the present invention, a shaft has one end connected to the ball
member. The affixation member will comprise a threaded surface formed on the
shaft. The threaded surface engages another human bone adjacent to another
component of the joint. The securing member includes at least one screw having
an end embedded in the first cup member. The human bone is the femoral head of
a human hip. The threaded surface engages the pelvic bone adjacent to the acetabulum
area.
The present
invention is further a method of forming an artificial human joint which
comprises the steps of: (1) forming a first cup member having a hemispherical
cavity of no more than one inch therein; (2) drilling a hole through two
components of the human joint; (3) implanting the first cup member into one of
the two components and into a portion of the drilled hole such that the
hemispherical cavity faces the other component; (4) implanting a shaft having a
ball member at one end into the other of the two components of the human joint
and into a portion of the hole such that the ball member extends outwardly of
the other of the components; and (5) engaging the ball member into the
hemispherical cavity. In this method, a lining material is installed into the
hemispherical cavity such that the lining material surrounds the hemispherical
cavity.
The step of
drilling in this method includes the steps of initially drilling a small hole
through the two components of the human joint. A guide wire is fastened into
the drilled hole such that the guide wire extends through and outwardly of the
drilled hole. The guide wire receives a reaming device such that the reaming
device reams a bore into a bone at the joint having a diameter suitable for
allowing the first cup member to pass therethrough and for receiving the first
cup member therein. After the bore has been suitably reamed, the guide wire can
be removed from the drilled hole. The area between the shaft and the wall of
the bore can be filled with a cementing material.
In the method of
the present invention, the shaft is permanently affixed by attaching a surgical
nail through a bone of one of the two components of the joint such that the
nail engages the shaft so as to retain the shaft in a fixed position. The cup
member is permanently affixed within the bones by placing at least one surgical
screw through the other of the two components such that an end of the screw
engages the first cup member so as to retain the cup in a fixed position.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an
exploded, partially cross-sectional view of the joint replacement system of the
present invention.
FIG. 2 is an
exploded, partially cross-sectional view showing the forming of the joint
replacement system of the present invention.
FIG. 3 is a
partially cross-sectional view of a first alternative embodiment of the joint
replacement system of the present invention.
FIG. 4 is a frontal
partially cross-sectional view of a second alternative embodiment of the
present invention as used in association with a human knee.
FIG. 5 is a frontal
partially cross-sectional view of the preferred embodiment of the present
invention as used in association with a human knee.
FIG. 6 is a
partially cross-sectional view showing the second alternative system of FIG. 4
as used in association with a human hip.
FIG. 7 is a third
alternative embodiment of the present invention showing a dual system as used
with a human knee joint.
FIG. 8 is a fourth
alternative embodiment of the present invention showing the joint replacement
system of the present invention as used with a human hip.
FIG. 9 is a fifth
alternative embodiment of the present invention showing a ring and bearing
system for the joint replacement system.
DETAILED DESCRIPTION OF THE PRESENT INVENTION
Referring to FIG.
1, there is shown at 10 the joint replacement system in accordance with the
preferred embodiment of the present invention. As shown in FIG. 1, the
artificial joint system 10 is shown as applied to a human hip 12. The
human hip 12 includes a pelvic bone 14 and a femur 16. The artificial
joint system is, in particular, applied to the acetabulum area 18 of the pelvic
bone 14 and to the femoral head 20 of the femur 16.
As can be seen in
FIG. 1, a first cup member 22 is shown as implanted within the pelvic bone 14
adjacent to the acetabulum area 18. This first cup member 22 has a
hemispherical cavity 24. An internal lining material 26 is shown, in an
exploded view, as received within the interior cavity 24 of the first cup
member 22. The cup member 22 should be of a rigid material, such as carbide
steel, titanium, a cobalt chromium alloy, or other rigid non-biodegradable
materials. The lining material 26, on the other hand, should be of a generally
flexible material such as polyethylene, TEFLON (TM) or other non-biodegradable
materials. It is important that the lining material 26 have a long life. The
lining material 26 should be of a low-friction material so that movement of the
hip joint is facilitated rather than restricted by the arrangement of the
lining material 26. The lining material 26 can be placed within the
hemispherical cavity 24 and sealed within the cavity by known means.
A ball
member 28 is received within the hemispherical cavity 24 and within the
lining material 26. The ball member 28 has a shaft 30
affixed to a surface thereof. Shaft 30 extends from ball 28
and into the femoral head 20 of the femur 16 and inwardly
toward the greater trochanter area 32 of the femur 16. When
the ball 28 is properly installed within the cup member 22,
the femoral head 20 can suitably rotate within the acetabulum area
18. The ball member will have a diameter of no more than one inch.
It is important to
be able to secure the cup member 22 in its proper position facing the
acetabulum area 18 of the pelvic bone 14. As such, securing members 34 and 36
are provided so as to engage the cup member 22. It can be seen that the
securing members 34 and 36 are surgical screws which are installed through the
pelvic bone 14 so as to threadedly engage the cup member 22. Such surgical
screws are known in the art. Typically, surgical screws 34 and 36 are
self-tapping screws which can be inserted into the material of the first cup
member 22 by rotating the ends of the screws 34 and 36. The exact position of
the screws 34 and 36 relative to the first cup member 22 can be observed by
fluoroscopy during the surgical procedure. Similarly, it is necessary to secure
the shaft 30 within the femoral head 20 of
the femur 16. As such, a surgical nail 38 can be installed
so as to extend through the greater trochanter area 32 and into the
femoral cavity. The nail 38 can be installed by known surgical
techniques. The nail 38 will engage the shaft 30 at an area
distal the ball member 28. Surgical screws 41 and 43 engage
the distal end of nail 38. Surgical screws are secured into and
through the femur 16 and are trapped through nail 38.
In the present
invention, a spacing ring 40 is placed around the exterior of
the shaft 30 as to be interposed between the ball member 28
and the surface of the femoral head 20. Spacer member 40
can be sized or provided in multiple numbers so as to provide proper spacing
between the femoral head 20 and the interior surfaces of the
acetabulum area 18.
When installed, the
small size of the ball member 28 and the cup member 24 allows for
proper rotatable and cantable movement of the femur 16 with respect
to the pelvic bone 14. During the surgical procedure, a capsulectomy is
performed so as to remove materials in the acetabulum area 18. It has been
found that suitable support is provided between the bone structures of the
pelvic bone 14 and the femoral head 20 to allow for a long life of
the joint system 10. Unlike existing surgical procedures, there is no
need to carry out the extensive tasks of reaming the acetabulum area 18 or the
removal of the femoral head 20. The femoral head 20 will
remain as is and in place with the ball member 28 suitably positioned
thereon. The capsulectomy and the forming of the various holes and openings can
be carried out through fluoroscopic and arthroscopic procedures.
FIG. 2 shows the
initial technique for the installation of the system 10 of the
present invention. Initially, a small hole is drilled through the greater
trochanter area 32 and through the femoral head 20. This small
hole will be drilled so as to extend through the femoral head 20 and
into the acetabulum area 18 of the pelvic bone 14. This small hole can be
drilled by existing surgical techniques. After the small hole has been drilled,
a guide wire 44 is inserted through the small hole formed in the pelvic bone 14
and through the small hole 46 formed in the femur 16. This guide wire
44 can be anchored by known surgical techniques.
Once the guide wire
44 is in a suitable position, a reaming devices can be attached to the guide
wire 44. Initially, a large diameter reaming device is provided so as to form a
bore 42 extending therealong. This bore 42 is shown in broken line fashion. The
diameter of the bore should be of a suitable diameter to accommodate the first
cup member 22. As such, this bore 42 will have a diameter of no more than one
inch. The bore 42 which is formed over the existing hole 46 will also be
suitable for the receipt of shaft 30 therein. The guide wire 44 can
remain in place so as to allow for the installation the first cup member 22 and
of the shaft 30 and its associated ball member 28.
Alternatively, if possible, the guide wire 44 can be removed so that
the shaft 30 and its associated ball member 28 (and possible spacer
rings 40) can be placed within the formed bore in the femur 16. The
guide wire can also remain in place so that the first cup member 22 can be
properly positioned adjacent to the surface of the acetabulum area 18. When
these components are properly placed, the screws 34 and 38 can be actuated
so as to secure the first cup member 22 in place. Similarly,
the nail 38 can be inserted through the femur 16 so as to
secure the shaft member 30 in place. The shaft can be cemented in
place within the bore 42. The femoral head 20 of
the femur 16 can then be pushed such that the ball
member 28 engages the interior cavity 24 of the first cup member 22.
Surgical closure of any incisions or surgical openings can then be carried out
in a known manner.
FIG. 3 shows an
alternative embodiment of the present invention. As can be seen in FIG. 3,
a cup member 60 is inserted into the pelvic bone 62 in the manner
described herein previously. Screws 64 and 66 are installed through the pelvic
bone 62 so as to secure the cup member 60 in its proper position.
Another cup member 68 is placed into the femoral head 69 of the femur 70. The
cup member 68 has an interior lining surrounding the hemispherical cavity of
cup member 68. The opening which is used to receive the second cup member 68
can be formed by the techniques described herein previously. It is simply
necessary that a larger hole be formed adjacent and into the femoral head 69 at
the area adjacent to the acetabulum area 72 of the pelvic bone 62. As can be
seen, a ball member 74 is received within the first cup member 60 and
within the second cup member 68. In this embodiment of the present invention,
the surface of the femoral head 69 will be in close contact with the surface of
the acetabulum area 72. The second cup member 68 is secured to a shaft 76. Shaft
76 extends into the greater trochanter area 78 of the femur 70. A nail 80 will
extend through the femur 70 transverse to the shaft 76 of the second cup member
68 so as to secure the shaft 76 and the second cup member 68 in their desired
positions.
FIG. 4 shows the
installation of the present invention, in another embodiment, with a knee joint
100. The knee joint 100 has upper component 102 and lower component 104. As can
be seen, a first cup member 106 is installed on the end surface 108 of the upper
component 102. Screws 110 and 112 are used so as to secure the first cup member
106 in its desired position. Similarly, a second cup member 114 is installed
within the top surface 116 of the second component 104 of knee 100. The second
cup member 114 is secured in place through the use of surgical screws 118 and
120.
Unlike the previous
embodiments of the present invention, the embodiment shown in FIG. 4 employs a
first ball member 122 and a second ball member 124. A rod 126 connects the
first ball member 122 to the second ball member 124. The first ball member 122
is received within the first cup member 106. The second ball member 124 is
received within the second cup member 114. As such, proper movement is
achieved, in a normal fashion, between the upper component 102 and the lower
component 104 of knee 100.
FIG. 5 shows
another form of the present invention as applied to knee 130. As can be seen in
FIG. 5, a first cup member 132 is formed in the upper component 134 of knee
130. Screws 136 and 138 are used so as to secure the first cup member 132 in a
desired position. A ball member 140 is received within the first cup member
132. The ball member 140 has a shaft 142 affixed thereto and extending into the
lower component 144 of knee 130. A spacer ring 146 is used to facilitate the
proper spacing between the upper component 132 and the lower component 144 of
knee 130. A nail 148 is used so as to secure the shaft 142 in its desired
position. As can be seen, the present invention can be employed so as to establish
the proper jointed relationship between the knee components.
FIG. 6 shows the
embodiment illustrated in FIG. 4 as applied to a hip joint 200. Hip joint 200
includes pelvic bone 202 and femur 204. The first cup member 206 is installed
adjacent to the acetabulum area 208 of the pelvic bone 202. Screws 210 and 212
are employed so as to secure the first cup member 206 in its desired position
adjacent to the acetabulum area 208. A second cup member 214 is placed on the
femoral head 216 of femur 214. Screws 218 and 220 are used so as to secure this
second cup member 214 in its desired position. Screws 218 and 220 can be
installed in standard surgical procedures.
In the embodiment
of FIG. 6, a first ball member 222 is received within the hemispherical cavity
of the first cup member 206. A second ball member 224 is received within the
hemispherical cavity of the second cup member 214. Rod 226 will extend between
the first ball member 222 and the second ball member 224. Rod 226 will have a
suitable length so as to establish proper spacing between the femoral head 216
of femur 204 and the acetabulum area 208 of the pelvic bone 202.
FIG. 7 shows a knee
joint 250 with an upper component 252 and a lower component 254. As can be
seen, a dual system of sockets 256 and 258 with ball members 260 and 262,
respectively, are employed. Each of the ball members 260 and 262 have shafts
264 and 266, respectively, attached thereto. The shafts 264 and 266 will extend
into the second component 254 of the knee 250. This arrangement is provided so
as to give additional rigidity and structural support to the knee joint 250. As
described herein previously, suitable surgical screws and nails can be
installed to affix the cup members 256 and 258, along with the shafts 264 and
266, in their proper position relative to the components of knee 250.
FIG. 8 shows
another embodiment 300 of the artificial joint system of the present invention.
In the embodiment 300, as shown in FIG. 8, the pelvic bone 302 receives a
threaded shaft 304 attached to ball member 308. The shaft 304 is threaded so
that it can properly engage a hole 310 formed in the pelvic bone 302 adjacent
to the acetabulum area 312. The threads on the shaft 304 are suitable for
engaging the surfaces of hole 310 such that the shaft 304 is rigidly retained
in position. The femur 314 has a femoral head 316. A first cup member 318 is
affixed within the femoral head 316 of the femur 314. In this arrangement, the
ball 308 is received within this first cup member 318. Screws 320 and 322 are
installed into the femoral head 316 so as to retain the cup member 318 in its
desired position. A rod 324 is provided so as to serve to space the distance
between the ball member 308 and the threaded shaft 304 so as to properly space
the distance between the acetabulum area 312 of the pelvic bone 302 and the
femoral head 316 of the femur 314.
FIG. 9 shows
another embodiment 400 of the present invention. In this form of the
present invention, a first shaft 402 is secured within
the pelvic bone 404 in accordance with any of the various techniques
described herein previous. Similarly, another shaft 406 is installed
so as to extending through the femoral head 408. An axle-and-ring
system 410 connects the first shaft 402 to the other
shaft 406. The axle-and-ring system 410 is initially formed such that
the first shaft 402 is connected to the second shaft 406
prior to installation. The axle-and-ring system allows for proper joint-like
movement between the joint components.
Importantly, in the
present invention, the installation of the artificial joint avoids many of the
complicated and dangerous proceedings associated with common hip, knee and
elbow replacement surgeries. In the present invention, it is not necessary to
remove the femoral head of the femur. Additionally, it is not necessary to ream
the acetabulum area completely of the pelvic bone. As a result, only a minimal
incision is required to carry out the installation of the hip joint of the
present invention. Incisions are only required so as to carry out the necessary
reaming for the installation of the various shaft and cup components of the
present invention. Surgical screws and nails are installed in a simple surgical
and non-invasive manner. In theory, the entire process of installing the
artificial joint system of the present invention can be carried out through
arthroscopic and fluorosopic guide procedures. Ideally, only a very minimal
hospital stay is required for recovery and very minimal rehabilitation efforts
will be required in order to restore full movement of the joint.
The foregoing
disclosure and description of the invention is illustrative and explanatory
thereof. Various changes in the details of the illustrated construction may be
made within the scope of the appended claims without departing from the true
spirit of the invention. The present invention should only be limited by the
following claims and their legal equivalents.
I claim:
1. A replacement
system for a joint comprising: a first cup member having an interior lining
material, said first cup member having a generally hemispherical cavity
therein, said interior fining material generally surrounding said hemispherical
cavity; a ball member received within said hemispherical cavity, said ball
member being cantable within said cavity;
a securing means
connected to said first cup member for affixing said first cup member within a
human bone adjacent one component of the joint; an affixation means
interconnected to said ball member for affixing said ball member within another
human bone adjacent another component of the joint; and a second cup member
having an interior lining said second cup member forming a generally
hemispherical cavity therein said interior lining material surrounding said
hemispherical cavity of said second cup member, said ball member having a portion
received within said second cup member, said first cup member and said second
cup member generally surrounding said ball member, said affixation means
connected to said second cup member so as to secure said second cup member and
said ball member within another human bone.
2. The system of
claim 1, said ball having a diameter of no more than one inch.
3. The system of
claim 1, said securing means being at least one screw having one end embedded
in said first cup member.
4. The system of
claim 3, said affixation means being a shaft affixed at one end to said ball
member, said affixation means further comprising a nail engaged with said shaft
distal said ball member.
5. The system of
claim 1, further comprising: a spacer ring extending around said shaft.
6. The system of
claim 1, said affixation means comprising at least one screw having an end
embedded in said second cup member.
7. The system of
claim 1, further comprising: a shaft having one end connected to said ball
member, said affixation means comprising a threaded surface formed on said
shaft, said threaded surface for engaging said another human bone adjacent to
said another component of the joint.
8. The system of
claim 7, said securing means comprising at least one screw having an end
embedded in said first cup member.
9. A replacement
system for a joint comprising: a first cup member having an interior lining
material, said first cup member having a generally hemispherical cavity
therein, said interior lining material generally surrounding said hemispherical
cavity; a ball member received within said hemispherical cavity, said ball
member being can table within said cavity; a securing means connected to said
fist cup member for affixing said first cup member within a human bone adjacent
one component of the joint; an affixation means interconnected to said ball
member for affixing said ball member within another human bone adjacent another
component of the joint; a second cup member having an interior lining, said
second cup member forming a generally hemispherical cavity therein, said
interior lining generally surrounding said hemispherical cavity in said second
cup member; a second ball member received within said hemispherical cavity of
said second cup member, said second ball member being cantable within said
second cup member; and a rod having one end connected to said first ball member
and an opposite end connected to said second ball member.
10. A method of
forming an artificial human joint comprising: forming a first cup member having
a hemispherical cavity therein, said hemispherical cavity having a diameter of
not more than one inch; drilling a hole through two components of the human
joint, said step of drilling comprising the steps of: fastening a guide wire
into the drilled hole, said guide wire extending through and outwardly of said
drilled hole; reaming a bore along said guide wire into a bone at the joint
having a diameter suitable for receiving said first cup member; removing said
guide wire from said drilled hole; and cementing areas between exterior
surfaces of said shaft and an interior wall of the bore; implanting said first
cup member into one of the two components of the human joint and into a portion
of said hole, said hemispherical cavity facing the other of said two
components; implanting a shaft having a ball member at one end into the other
of said two components and into another portion of the drilled hole such that
said ball faces said hemispherical cavity; and engaging said ball member into
said hemispherical cavity.
11. The method of
claim 10 said step of forming comprising: installing a lining material into
said hemispherical cavity such that said lining material surrounds said
hemispherical cavity.
12. The method of
claim 10, said step of implanting comprising: affixing a nail through a bone of
said one of the two components of the joint, said nail engaging said shaft so
as to retain said shaft in a fixed position.
13. The method of
claim 10, said step of implanting further comprising: placing a spacer ring
around said shaft adjacent to said ball, said spacer ring being interposed
between said ball and an outer surface of said one of the two components.
14. The method of
claim 10, further comprising the step of: placing at least one screw through
said other of the two components such that an end of the screw engages said
first cup member so as to retain said first cup member in a fixed position.
15. The method of
claim 10, the human joint being a hip joint having a pelvic bone with an acetabulum
area and a femur with a femoral head, said shaft extending into said femur such
that said ball resides on an existing surface of the femoral head, said first
cup member being implanted into said acetabulum area of said pelvic bone.
16. The method of
claim 10, the human joint being a hip joint having a pelvic bone with an
acetabulum area and a femur with a femoral head, said first cup member being
implanted into a surface of the femoral head, said shaft extending into said
acetabulum area of said pelvic bone.
17. The method of
claim 16, said shaft being externally threaded, said step of implanting
comprising: threadedly engaging said shaft with an internally threaded area in
said pelvic bone at said acetabulum area.
References Cited
U.S. PATENT DOCUMENTS
2.947,308 8/1960 Gorman 623/23
3,543,749 12/1970 Grove 623/23
3,843,975 10/1974 Tronzo 623/23
4,206,517 6/1980 Pappas et al. 623/18
4,783,192 11/1988 Wroblewski et al. 623/23
4,840,632 6/1989 Kampner. 623/18
4,846,840 7/1989 Leclercq et al. 623/18
4,895,572 1/1990 Chernoff 623/23
5,376,125 12/1994 Winkler 623/23
FOREIGN PATENT DOCUMENTS
634153 1/1995 European Pat. Off. 623/22
284.5231 5/1979 Germany 623/22
1708329 1/1992 U.S.S.R. 623/18
External links
Shah MK. Joint replacement system. US6010535A April 30, 1998. 2000. patents.google
Authors & Affiliations
Mrugesh K. Shah – Trailscourt, Houston, Tex., US.
Keywords
ligamentum capitis femoris, ligamentum teres, ligament of head of femur, endoprosthesis, prosthesis, invention, unipolar, subtotal
NB! Fair practice / use: copied for the purposes of criticism, review, comment, research and private study in accordance with Copyright Laws of the US: 17 U.S.C. §107; Copyright Law of the EU: Dir. 2001/29/EC, art.5/3a,d; Copyright Law of the RU: ГК РФ ст.1274/1.1-2,7
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