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Medical Patent Abstract
A medical implant and method for implantation of the same. One embodiment
is an implant for use in the treatment of stress urinary incontinence
that includes an implantable, elongated tape having a multiplicity
of openings formed through the thickness thereof, the tape having
a first end region and a second end region longitudinally opposite
the first end region, and first and second bio-compatible fixation
elements attached to the first and second end regions of the tape
respectively. Each bio-compatible fixation element has a tissue
adherence property greater than that of the tape.
Medical Patent Claims
What is claimed is:
1. An implant for use in the treatment of stress urinary incontinence
in a patient, comprising: an implantable, elongated tape having
a multiplicity of openings formed through the thickness thereof,
the tape having a first end region and a second end region longitudinally
opposite the first end region; and first and second bio-compatible
fixation elements attached to the first and second end regions of
the tape respectively, each bio-compatible fixation element having
a tissue adherence property greater than that of the tape, wherein
the tape includes a top side and a bottom side, the top side have
a first marking thereon and the bottom side having a second marking
thereon, the second marking being different from the first marking
to thereby distinguish the top side from the bottom side.
2. An implant for use in the treatment of stress urinary incontinence
in a patient, comprising: an implantable, elongated tape having
a multiplicity of openings formed through the thickness thereof,
the tape having a first end region and a second end region longitudinally
opposite the first end region; and first and second bio-compatible
fixation elements attached to the first and second end regions of
the tape respectively, each bio-compatible fixation element having
a tissue adherence property greater than that of the tape wherein
the tape includes a plurality of spaced apart filament tangles attached
thereto.
3. A method of implanting an implant in a patient for the treatment
of stress urinary incontinence, the method comprising the steps
of: providing an implant including an implantable, elongated tape
portion having a multiplicity of openings formed through the thickness
thereof, and having a first end region and a second end region longitudinally
opposite the first end, and first and second bio-compatible fixation
elements attached to the first and second end regions of the tape
respectively, each bio-compatible fixation element having a stiffness
and/or tissue adherence property greater than that of the tape;
making an incision in the vaginal wall of the patient; inserting
the first fixation element and attached tape through the incision
and into connective tissue attached to the pubic bone to a first
side of the patient's uretha; inserting the second fixation element
and attached tape through the incision and into connective tissue
attached to the pubic bone on the opposite side of the patient's
urethra such that the tape forms a loop partially around the urethra
to provide support for the urethra; and leaving the implant implanted
in the body of the patient, wherein the first and second inserting
steps further comprise inserting the first and second fixation elements
respectively into connective tissue at the lower edge of the pubic
bone.
Medical Patent Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to minimally invasive medical
implants and procedures for their use and insertion device for implanting
the same, having particular application for treating urinary incontinence.
2. Description of the Prior Art
Stress urinary incontinence (SUI) is a female medical condition
commonly associated with weakening of the pelvic muscles and/or
connective tissues that support the urethra in its proper position.
As a result of this condition, involuntary urine leakage occurs
from simple physical activity, such as running or jumping, and even
coughing or sneezing, as the urethra is not properly supported and
does not remain fully closed during such activity.
A widely accepted medical procedure to correct SUI is the insertion
of a tension-free or trans-vaginal tape that is surgically implanted
in the pelvic tissue and that extends under and provides support
for the urethra when pressure is exerted thereon.
U.S. Pat. No. 5,899,909, the disclosure of which is incorporated
herein by reference, describes in detail a typical procedure for
treating SUI using a trans-vaginal tape. The tape is implanted by
passing an elongated curved needle that is attached to one end of
the tape through an incision in the vaginal wall, to one lateral
side of the urethra, through the pelvic tissue behind the pubic
bone, and exiting out through an incision made in the abdominal
wall. The procedure is repeated for the other end of the mesh tape,
this time on the other lateral side of the urethra, with the needle
exiting through a second incision made in the abdominal wall of
the patient. After the mesh tape is adjusted for proper support
of the urethra, its free ends extending outside of the abdominal
wall are trimmed. Over time, fibroblasts grow into the mesh tape
to anchor the tape in the surrounding tissue. Thus, the tape is
left as an implant in the body to form an artificial ligament supporting
the urethra in order to restore urinary continence. In another known
method for implanting a trans-vaginal tape, the tape is inserted
in a somewhat similar manner, but is brought out through the obturator
hole and exits the body through a small incision in the upper leg.
The use of trans-vaginal tape for treating SUI has a number of
advantages. It does not need to be attached through bone anchors,
sutures or any other element to secure the tape in place, and there
is minimal scarring. The procedure takes about 30 to 50 minutes,
and may be performed on an outpatient basis under local, regional
or general anesthesia. One of the few disadvantages of known procedures
for implanting sub-urethral tapes is that the use of needles to
pass the tape through the body poses a risk for vessel, bladder
and bowel perforation. Also they require two separate, minimal incisions
made through the abdominal wall (for a retropubic approach) or the
upper leg (for an obtuator approach) through which exit the curved
needles and attached tape is passed. This, of course, increases
the risk of post-operative pain and/or infection to at least a small
degree.
Accordingly, what is needed is an improved sub-urethral tape, and
device and method for implanting the same.
SUMMARY OF THE INVENTION
The present invention provides an implant for use in the treatment
of stress urinary incontinence in a patient that includes an implantable,
elongated tape having a multiplicity of openings formed through
the thickness thereof, the tape having a first end region and a
second end region longitudinally opposite the first end region,
and first and second bio-compatible fixation elements attached to
the first and second end regions of the tape respectively, with
each bio-compatible fixation element having a tissue adherence property
greater than that of the tape.
Also provided is an implant for use in the treatment of stress
urinary incontinence in a patient including an implantable, elongated
tape having a multiplicity of openings formed through the thickness
thereof, the tape having a first end region and a second end region
longitudinally opposite the first end region, and first and second
bio-compatible fixation elements attached to the first and second
end regions of the tape respectively, with each bio-compatible fixation
element having a stiffness greater than that of the tape.
A method of implanting an implant in a patient for the treatment
of stress urinary incontinence is also provided, wherein the method
includes the steps of providing an implant including an implantable,
elongated tape portion having a multiplicity of openings formed
through the thickness thereof, and having a first end region and
a second end region longitudinally opposite the first end, and first
and second bio-compatible fixation elements attached to the first
and second end regions of the tape respectively. Each bio-compatible
fixation element has a tissue adherence property greater than that
of the tape. The method further includes the steps of making an
incision in the vaginal wall of the patient, inserting the first
fixation element and attached tape through the incision and into
the pelvic or any obturator tissue of the patient on one lateral
side of the urethra and without exiting the body, inserting the
second fixation element and attached tape through the incision and
into the pelvic or any obturator tissue of the patient and on an
opposite lateral side of the urethra without exiting the body such
that the tape forms a loop partially around the urethra to provide
support for the urethra, and leaving the implant implanted in the
body of the patient.
Finally, a method is also provided for implanting an implant in
a patient for the treatment of stress urinary incontinence which
includes the steps of providing an implant including an implantable,
elongated tape portion having a multiplicity of openings formed
through the thickness thereof, and having a first end region and
a second end region longitudinally opposite the first end, and first
and second bio-compatible fixation elements attached to the first
and second end regions of the tape respectively. Each bio-compatible
fixation element has a stiffness and/or tissue adherence property
greater than that of the tape. The method further includes the steps
of making an incision in the vaginal wall of the patient, inserting
the first fixation element and attached tape through the incision
and into connective tissue attached to the pubic bone to a first
side of the patient's urethra, inserting the second fixation element
and attached tape through the incision and into connective tissue
attached to the pubic bone on the opposite side of the patient's
urethra such that the tape forms a loop partially around the urethra
to provide support for the urethra, and leaving the implant implanted
in the body of the patient.
The present invention also provides an implant for medical procedures
having a mesh structure having a multiplicity of openings formed
through the thickness thereof, with the mesh structure having at
least a first connection region and a second connection region,
and first and second bio-compatible fixation elements attached to
the first and second connection regions respectively. The bio-compatible
fixation elements each have a tissue adherence property greater
than that of the mesh.
Yet another implant for medical procedures is provided including
a mesh structure having a multiplicity of openings formed through
the thickness thereof, with the mesh structure having at least a
first connection region and a second connection region, and first
and second bio-compatible fixation elements attached to the first
and second connection regions respectively. The bio-compatible fixation
elements have a substantially planar and rectangular configuration
and have a stiffness greater than that of the mesh structure.
These and other objects, features and advantages of the present
invention will be apparent from the following detailed description
of illustrative embodiments thereof, which is to be read in connection
with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an isometric view of one example, of a medical implant
in accordance with the present invention which is particularly suited
for treatment of stress urinary incontinence.
FIG. 2 is a bottom isometric view of the implant shown in FIG.
1.
FIG. 3 is an enlarged isometric view of a portion of the implant
formed in accordance with the present invention and shown in FIG.
1.
FIG. 4 is a partially exploded isometric view of the implant shown
in FIG. 1 and shown with one example of a protective sheath.
FIG. 4A is a partially exploded isometric view of the implant shown
in FIG. 4 with another form of a protective sheath shown in an open
state to receive the tape.
FIG. 4B is an isometric view of the implant and protective sheath
shown in FIG. 4, the protective sheath being shown folded to at
least partially envelop the tape.
FIG. 4C is a partially exploded isometric view of the implant shown
in FIG. 4 with yet a further form of a protective sheath shown in
an open state to receive the tape.
FIG. 5 is a top plan view of a portion of an implant formed in
accordance with another embodiment of the present invention.
FIG. 6 is a cross-sectional view of the implant shown in FIG. 5,
taken along line 6-6 of FIG. 5.
FIG. 7 is a diagrammatic illustration of an implant of the present
invention being surgically implanted in the body of a patient prior
to sheath removal.
FIG. 8 is one diagrammatic illustration of an implant of the present
invention shown surgically implanted in the body of a patient after
proper placement and sheath removal.
FIG. 9 is a partial isometric and exploded view of one form of
an insertion tool, shown overlying one end of an implant, both of
which are formed in accordance with the present invention, for surgically
implanting the implant in the body of a patient.
FIG. 10 illustrates one end of another embodiment of an implant
according to the present invention.
FIG. 10a illustrates the shape of the implant of FIG. 10 when implanted
and under tension.
FIG. 11 illustrates another embodiment of an implant according
to the present invention.
FIG. 12 is a perspective view illustrating another embodiment of
an insertion device according to the present invention.
FIG. 12a illustrates the device of FIG. 12 with the implant holding
element in a second position.
FIG. 13 is a side view of the insertion device of FIG. 12.
FIG. 14 is an enlarged view of the distal end region of the insertion
device of FIG. 12 holding an implant.
FIGS. 15a-c illustrates various insertion steps using an implant
and insertion device according to the present invention.
FIG. 16 illustrates an alternative placement of an implant according
to the present invention.
DETAILED DESCRIPTION
Although the present invention is described in detail in relation
to its use as a sub-urethral tape for treating stress urinary incontinence,
it is to be understood that the invention is not so limited, as
there are numerous other applications suitable for such an implant.
For example, implants incorporating novel features described herein
could be used for repairing pelvic floor defects such as, but not
limited to, cystoceles and rectoceles, and for hernia repair or
other prolapse conditions, or for supporting or otherwise restoring
other types of tissue.
Turning initially to FIGS. 1-3 of the drawings, one embodiment
of an implant 2 in the form of a sub-urethral tape particularly
suited for the treatment of stress urinary incontinence (SUI) includes
an implantable, elongated tape 4. The main tape portion 4 has a
multiplicity of openings formed through the thickness thereof, and
includes a first end 6 and a second end 8 longitudinally opposite
the first end 6.
Preferably, the tape 4 is formed as a mesh or netting with openings
formed through the thickness thereof of the order of about 1 millimeter
to allow fibroblasts to grow into the tape for securing the tape
in the surrounding tissue of the patient. A suitable material for
the tape is PROLENE.RTM., which is a knitted or woven polypropylene
mesh having a thickness of approximately 0.7 millimeters, and which
is manufactured by Ethicon, Inc., Somerville, N.J. This material
is approved by the FDA in the United States for implantation into
the human body.
The PROLENE.RTM. tape mentioned above is a non-absorbable mesh.
However, it is envisioned to be within the scope of the invention
to have the tape 4 formed of a knitted or woven material or netting
that is bioabsorbable over time, or that can vary in pore size,
fiber thickness, construction, size and/or properties.
The elongated tape 4 may be coated on one or more sides with a
fibroblast stimulating substance, for example, an enamel matrix
derivative.
In a further embodiment shown in FIGS. 5 and 6, a plurality of
spaced apart synthetic filament tangles 10 may be attached to the
top side 12 and/or the opposite bottom side 14 of the tape 4 so
as to extend outwardly from the surfaces of the top and bottom sides
for stimulating scar tissue growth and attachment to the tape 4.
The visible mesh tape 4 will be suitably dimensioned in accordance
with its application(s) as described. For example, one embodiment
described in detail below that is particularly suitable for treatment
of stress urinary incontinence in women has a width of approximately
10-12 millimeters, and has a length L.sub.1 between about 15 millimeters
and about 150 millimeters, preferably 40 millimeters. The total
length of the implant L.sub.2 including the fixation elements 16
can be from about 35 millimeters up to about 250 millimeters, and
preferably about 80 mm millimeters. As will be explained in greater
detail below, the length of the implant 2 may vary since the fixation
elements 16 may be trimmed or cut transversely depending upon the
insertion method and the needs of the physician during surgical
implantation of the tape. Further, the length may vary according
to the desired use and/or placement of the implant
Returning again to FIGS. 1-3, the implant may further include a
bio-compatible and preferably bio-absorbable polymer fixation element
16 attached to each of the first and second end regions 6, 8 of
the visible main tape portion 4. In one embodiment, each bio-absorbable
polymer fixation element 16 has tissue adherence properties for
securing in vivo the implant to surrounding tissue of the patient
in whom the implant is implanted without requiring any other means
for physical attachment such as anchoring mechanisms or the like.
By "tissue adherence property" what is meant is the ability
of the implant to have relative immediate and positionable fixation
(even if by temporary means) into sturdy tissue without the need
for immediate tissue ingrowth. In yet another embodiment, the fixation
elements simply have a stiffness greater than that of the main tape
portion, which enables the fixation elements to be firmly held on
to the insertion device, and when implanted within suitably sturdy
tissue such as connective tissue, to be firmly held within the tissue.
Other means for stiffening may also be used.
According to a preferred embodiment, the bio-absorbable fixation
elements 16 are created by assembling material or components of
a product sold under the name ETHISORB.RTM. Dura Patch, sold by
Codman, a Johnson & Johnson company, which is mainly a VICRYL.RTM.
polyglactin synthetic surgical composite material which is used
for tissue reinforcement in surgery. VICRYL.RTM. is a material manufactured
by Ethicon, Inc. of Somerville, N.J. ETHISORB.RTM. Dura Patch includes
a fleece made from VICRYL.RTM.(polyglactin 910) and PDS (poly-p-dioxanone)
undyed yarn which is sandwiched on one side with a piece of dyed
poly-p-dioxanone film. The film and fleece are bonded together in
a thermal process, which leaves the film intact as a sheet. The
film is dyed violet with D&C Violet No. 2 (color index No. 60725).
According to one embodiment, the ends of the PROLENE.RTM. tape can
be sandwiched between two pieces of ETHISORB.RTM. Dura patch, with
the components being thermally bonded together. According to a preferred
embodiment, however, the VICRYL.RTM. and PDS components of ETHISORB.RTM.
Dura patch are used to make the fleece portion, as well as the same
dyed poly-p-dioxanone film. The separate components, the fleece
pad and the dyed poly-p-dioxanone film sheet, are placed on one
side of the PROLENE.RTM. tape and a second fleece pad and dyed poly-p-dioxanone
film sheet are placed on other side. The 5-piece assembly is then
placed into a thermal process to bond the components together. The
thermal process is controlled to maintain the temperature such that
it only will melt the PDS yarn and dyed poly-p-dioxanone film. Use
of the separate components provides a non-pressed fleece that facilitates
subsequent bonding of the two film sheets through the mesh, since
the two fluffy fleece layers integrate into the weave of the PROLENE.RTM.
mesh during pressing. After the thermal pressing process, the dyed
poly-p-dioxanone film sheets no longer exist, as they are melted
forming a plethora of bond points between the mesh and fleece layers.
The fleece component described above is made from absorbable materials,
but could conceivable be made from non-absorbable material or a
combination thereof. The process of making the fleece starts similar
to other textiles where relatively straight yarn is taken in a preferred
ratio, with the ratio of VICRYL.RTM. to PDS in the preferred embodiment
being approximately 8:1. The single yarn strands are spun together
using common textile techniques, and the new strand is woven into
a sock like structure that is approximately 1-2 inches in diameter
and of a continuous length. The sock or tube like structure is woven
so that the lead thread can be pulled to unravel the tube, which
kinks the otherwise relatively straight 8:1 strand.
The sock or tube is fed into a loom, and a loose scarf-like material
sheet is woven approximately 8 inches wide. Because the kinked 8:1
strand was used, the resulting scarf structure is fluffy. The scarf
is then cut into lengths of approximately 12-18 inches. The cut
length is then place on a non heated plate, and a heated plate then
dropped over the non-heated plate trapping the scarf between a defined
gap. As the temperature of the scarf increases to a predetermined
temperature that is below the PDS yarns melting point, small melting
points are generated that hold the shape of the new fluffy fleece
structure. As the individual PDS yarn strands shrink and melt slightly
they pull the VICRYL.RTM. yarn strands with it. Further, as the
original scarf shrinks, it gets both thicker and smaller as the
open weave of the scarf closes up. The resulting new material is
an exemplary "fleece like material" as referenced above.
Although one preferred embodiment is described above, it is recognized
that improvements can be made that are intended to be within the
scope of the present invention. For instance, one may alter the
compositional ratio of absorbable polymers making up the material.
That is, use more of the poly(L(-)-lactide-co-glycolide) component
and less of the poly(p-dioxanone) component, or vice versa. It is
also recognized that in the case of the lactide/glycolide copolymer,
one might alter the relative amounts of the co-monomers. Thus one
might slightly increase the lactide level in the copolymer to reduce
crystallinity and increase the rate at which the component is absorbed.
It is also recognized that the geometrical nature of the fibrous
components of the fleece can be altered to provide enhanced gripping
of the tissue surfaces. One may provide a more non-circular cross-section
of the fibrous components, such as a cross-section that is flatter.
A star-shaped cross-section might also be utilized to enhance gripping.
Further, other absorbable polymers might be utilized to advantage
in practicing the present invention. Of particular utility are the
absorbable or bioabsorbable polymers prepared from lactone monomers
selected from the group consisting of p-dioxanone, glycolide, L(-)-lactide,
D(+)-lactide, meso-lactide, .epsilon.-caprolactone and trimethylene
carbonate or combinations thereof. In those surgical cases in which
tissue repair is compromised, such as in diabetic or elderly patients,
the absorption profile of the fixation elements might be adjusted
accordingly. Thus, one might make use of a high-lactide (co)polymer,
such as 95/5 poly(L(-)-lactide-co-glycolide) to advantage.
Besides the absorbable polymers prepared from lactone monomers
described above, one might utilize oxidized regenerated cellulose,
also known as ORC. This material, especially in a non-neutralized
state, is known to adhere to bodily tissue. The extent of oxidation
and acidity could be adjusted to enhance the adherence and also
provide anti-bacterial activity.
In a further aspect of the invention, the absorbable polymers may
be combined with antimicrobial agents to provide an added benefit.
It is recognized that other active ingredients might be added to
provide enhanced characteristics, such as pain reduction agents,
etc. The agents may be added to the polymer prior to formation of
the final material, added to the final material once fabricated,
or added to the fixation elements once fabricated.
It would not be unreasonable to assume that there are certain surgical
situations in which a non-absorbable permanent fixation elements
would be preferred. In this case the fixation elements could be
fabricated from a variety of materials, including but not limited
to non-absorbable polymers, metals, or ceramics. Non-absorbable
polymers include the polyolefins, such as polyethylene or polypropylene;
polyurethanes; polyesters, such as polyethylene terephthalate or
polybutylene terephthalate; and polyamides, also known as nylons,
such as nylon-6, nylon-66, or nylon-12.
As shown in the embodiment of FIG. 3 and as described above, each
fixation element 16 may include a first top portion 18 and a second
bottom portion 20. The first portion 18 is attached to the top side
of the tape and the second portion 20 is attached to the bottom
side of the tape. The tape may extend along only a portion of the
length of the fixation element, or in alternate embodiments may
extend fully along the length or simply secured to the extreme ends
of the tape. The fixation element portions 18, 20 may alternatively
be attached to the tape 4 by other well-known methods, such as by
using bio-compatible adhesives or the like.
The polymer fixation elements 16 of the embodiment of FIGS. 1-3
include a central body portion 22 and a plurality of longitudinally
spaced apart finger portions 24 extending outward laterally in opposite
directions from the central body portion 22. Preferably, each finger
portion 24 is generally triangular in shape, with the polymer fixation
element 16 taking on a generally arrow configuration, with a broad
base 26 at one end and a triangular or arrowhead-shaped tip portion
28 at the other end. The plurality of triangular-shaped finger portions
24 extend laterally outwardly between the base 26 and triangular
tip portion 28.
The triangular-shaped finger portions 24 may be spaced apart longitudinally
from adjacent finger portions by about 3-5 millimeters, and the
fingers on either side of the center portion may be shifted to further
enhance adjustability. The width of each polymer fixation element
16 measured between the most lateral extent of transversely disposed
finger portions 24 is preferably about 11 millimeters, which is
the preferred width of the tape 4 and the implant 2 overall. In
an alternate embodiment, the fingers may be very closely spaced,
on the order of 0.02 to 1.0 millimeters, and may have any configuration
other than triangular, so as not to resemble visible fingers. The
implant may further include interruptions in the pitch between the
"fingers." For example, in one preferred embodiment, the
"fingers" are spaced apart longitudinally by approximately
0.05 mm, with every other one removed. Alternatively, an irregular
cut surface that has no defined spacing longitudinally along it
can be used on one or both sides.
The finger portions 24 can be sharp, but preferably are formed
with a radius of about 0.1 and 2 millimeter at their most laterally
outwardly extending part 30, and are formed with a radius of about
0.1 and 2 millimeter at their most inwardly extending part 30, i.e.,
the area in between adjacent laterally outwardly extending portions
30 thereof, and the triangular tip 28 of each fixation element 16
has a transverse width of about 11 millimeters and a longitudinal
length that can vary from 3-10 millimeters. Furthermore, the fixation
elements 16 may be trimmed or cut across their transverse width
if the physician needs to shorten the overall length of the implant
2.
With this particular shape, the polymer fixation elements 16 are
envisioned to adhere to and/or engage the surrounding tissue, minimizing
backward slippage or forward sliding after the implant 2 is surgically
implanted in the patient. It is preferred that each fixation element
16 have a stiffness that is greater than the stiffness of the mesh
tape portion 4 in order to provide some rigidity and maintain its
overall shape. This prevents or minimizes slippage with respect
to the surrounding tissue to which they adhere and maintains the
overall integrity of the fixation elements during surgical implantation.
Stiffness of the whole fixation area can be changed through choice
of manufacturing process.
Although the embodiment of FIGS. 1-3 incorporates the finger portions
described above, the fixation areas may also simply have a rectangular
configuration, as shown in FIG. 10, so long as the fixation areas
are comprised of a material having a suitable stiffness and/or tissue
adhesive properties to secure the tape in place, such as the material
described above. In the embodiment of FIG. 10, a lower edge 17 of
the fixation area 16 has a cross-sectional area (along line a-a)
that is slightly larger than that of the mesh to which it attaches.
This difference in cross-sectional area may also be increased during
implantation since typically the tension on the mesh causes the
mesh to assume a slightly reduced width as shown in FIG. 10a.
As shown in FIG. 9 in particular, each fixation element 16 may
further include one or more holes 34, openings, slits or the like
formed through the thickness thereof and longitudinally spaced apart
from each other. These holes 34 may cooperate with one embodiment
of an insertion tool 36 for properly positioning the free ends of
the implant 2 in the pelvic or obturator tissue of the patient.
Such an insertion tool 36 may include an elongated rod 38 which
may be bendable to a desired curvature by the physician and which
retains its configured shape during the surgical procedure. The
rod 38 includes a proximate end 40 for grasping by the physician,
and a distal end 42 opposite the proximate end 40 for insertion
through an incision made in the top vaginal wall of a patient. The
distal end portion 42 includes one or more prongs 44 extending radially
outwardly from the rod 38 and spaced apart from one another. Each
prong 44 has a diameter that is equal to or slightly less than the
diameter of the holes 34 formed in the fixation elements 16, and
adjacent prongs 44 are separated from one another a distance equal
to the spacing between adjacent holes 34 formed in the fixation
elements. Accordingly, the prongs 44 of the insertion tool 36 are
receivable by the holes 34 formed in the fixation elements 16 so
that each free end of the implant 2 may be selectively secured to
the distal end 42 of the insertion tool for proper placement within
the pelvic tissue of the patient. Once properly positioned, the
implant 2 may be separated from the insertion tool 36 by the physician
manipulating the proximate end in order to maneuver the distal end
42 of the insertion tool slightly away from the implant 2 so that
the prongs 44 are released from their respective holes 34 in the
fixation elements. Various other methods of insertion will also
be apparent to those skilled in the art, such as any variation of
a forcep used to position the fixation areas, or other insertion
tools having suitable means by which to grasp and/or position the
fixation areas of an implant. Another preferred embodiment of an
insertion device will be described in detail below.
A second reason for having such holes 34 formed through the thickness
of the fixation elements 16 is that they facilitate the in-growth
of tissue through the fixation elements to further adhere them to
the surrounding tissue.
As shown in FIG. 4 of the drawings, according to one embodiment,
the implant 2, and in particular the tape 4 is covered on its top
and bottom sides with a removable plastic sheath 46. Each sheath
46 may include a cut or perforation 48 extending at least partially
across its width at its midpoint that overlies the midpoint of the
implant 2 to facilitate its removal from the top and bottom sides
12, 14 of the tape 4. It may further include a line or other marking
50 running transversely across the middle of the sheath 46, with
such line or other marking 50 being positioned at the midpoint of
the implant 2 so as to indicate to the physician where the midpoint
of the tape resides during the surgical implantation procedure.
Forceps may be used to remove the sheath 46 from the top and bottom
sides 12, 14 of the tape 4 during the implantation procedure. The
sheaths 46 may prevent the tape 4 from catching on the surrounding
tissue during insertion and positioning of the implant 2 within
the patient's body. Each sheath 46 preferably extends slightly beyond
the width of the tape 4 to ensure that the top and bottom sides
12, 14 and the lateral edges of the tape 4 will not catch on the
surrounding tissue during the surgical procedure. A sheath may also
allow protection against contamination or damage.
Other forms of protective sheaths are illustrated by FIGS. 4A-4C.
More specifically, FIGS. 4A-4C illustrate protective sheaths for
the implant that are formed as wrappers that may be folded over
the implant to at least partially envelop the tape during implantation.
Turning initially to FIGS. 4A and 4B, the protective sheath 46'
includes a back piece 60, preferably formed of two segments 61 positioned
end-to-end. In relation to the tape, the two segments 61 meet in
preferably the middle of the tape and extend perpendicularly outwardly
from the outer surface of the back piece to define together a tab
62. Each segment 61 of the back piece 60 forming the tab 62 may
be grasped by the physician using forceps to remove the protective
sheath 46' from the implant 2 after it has been properly positioned
and implanted in the patient.
The protective sheath 46' further includes foldable lateral pieces
64 attached to and extending from opposite sides of the back piece
60 at least partially along the longitudinal length of the back
piece. As can be seen in FIG. 4B, the implant 2 and sheath 46' are
assembled such that the bottom side of the implant rests on the
inner surface of the back piece 62, and the lateral pieces 64 of
the sheath are folded over the top side of the implant. The lateral
pieces 64 of the sheath 46' may be dimensioned to meet each other
at their free edges along the longitudinal centerline of the implant,
or may be dimensioned so that one lateral piece extends partially
overlapping the other lateral piece.
Preferably, as shown in FIGS. 4A and 4B, the protective sheath
46' may further include axial end pieces 66 attached to and extending
from opposite axial sides of the back piece 60. Each axial end piece
66 is preferably dimensioned to have a width and length that conform
to the width and length of the central body portion 22 of each fixation
element 16 so that they cover only one side of the central body
portion 22, leaving the other side of the central body portion 22,
and both sides of the finger portions 24, exposed. In this way,
during implantation and with the protective sheath 46' affixed to
the implant 2, the exposed portions of the fixation elements 16
will contact and be able to adhere to the surrounding tissue of
the patient.
FIG. 4C illustrates another form of a protective sheath 46'' for
use with the implant of the present invention. This sheath 46''
is the same as that shown in FIGS. 4A and 4B, except that it is
formed in two longitudinally disposed, individually foldable halves,
i.e., the back piece 60 and opposite lateral pieces 64 are each
formed by two separable segments 68 positioned longitudinally to
each other in an end-to-end fashion. Each half portion segment 68
of the sheath 46'' may be removed separately in the same manner
as described previously, that is, by the physician grasping portions
of the sheath back piece forming the tab 62 with forceps, so that
one half segment 68 of the sheath 46'' may be removed, if desired,
during partial implantation of the implant, or both half segments
68 may be removed after both ends of the implant 2 have been properly
positioned and implanted in the patient.
Additionally, the tape 4 may have its top side 12 formed with one
marking, such as a first color, and its bottom side 14 formed with
another marking, such as a second color that is different from the
first marking or color. This will allow the physician to know whether
the tape 4 is or has twisted during the surgical implantation procedure.
In other words, one of the top and bottom sides 12, 14 of the implant
2 should be facing toward the urethra as it is looped partially
thereabout, and the other of the top and bottom sides 12, 14, having
a different color or other marking which is visible to the physician,
should be facing away from the urethra during its surgical implantation
in the patient. Of course, it is envisioned that the sheath 46,
46', 46'', instead of the implant 2, may be similarly colored or
include distinguishing markings.
In addition to the mentioned markings on the fixation ends, the
mesh or sheath may be marked to describe the center of the mesh
loop or a zone may be marked to help the physician symmetrically
locate the mesh loop relatively to the urethra during implantation.
FIGS. 7 and 8 illustrate one procedure for surgically implanting
an implant 2 of the present invention in a patient to treat stress
urinary incontinence (SUI). First, a small incision 52 is made in
the top vaginal wall 54. The physician attaches the distal end 42
of the insertion tool 36 to one fixation element 16 of the implant
2 by inserting the prongs 44 into their corresponding holes 34 formed
through the fixation element. The physician may bend the insertion
tool to whatever curvature he feels is necessary to aid in the implantation
procedure.
By manipulating the proximate end 40 of the insertion tool 36,
the physician directs the distal end 42 of the tool with one end
of the implant 2 attached thereto through the surgical incision
52 and into the soft tissue on one lateral side of the urethra 56
and behind the pubic bone 58. The transverse marking(s) 50 on the
sheath 46, 46', 46'' will indicate to the physician the midpoint
or mid-zone of the implant 2 so that the physician can judge the
extent of tissue penetration and whether further insertion is required.
Due to its inherent tendency to adhere to the surrounding tissue,
the fixation element 16 secures the free end of the implant 2 to
the surrounding tissue it contacts. The physician now manipulates
the insertion tool 36 such that it frees itself of the fixation
element 16 and is removed, leaving the first half of the implant
2 implanted in the patient.
With the described insertion concept, and after insertion of the
first fixation element, the physician may recognize that the implant
is too long by comparing the middle marking or mid-zone of the implant
with the position of the urethra. If necessary, the second fixation
element 16 of the described implant may be trimmed to compensate
for the difference in length. Once trimmed to length, the physician
then attaches the distal end 42 of the insertion tool to the fixation
element 16 at the other end of the implant 2, and directs the tool
again through the vaginal wall incision 52 and so as to pass through
the soft tissue on the other lateral side of the urethra 56 and
behind the pubic bone 58. The physician then separates the insertion
tool 36 from the fixation element 16 at this second end of the implant
2 and removes the tool, leaving the tape in place and partially
looped around preferably the middle of the urethra 56. The second
fixation area 16 adheres to the surrounding tissue it contacts and
holds the second half of the implant 2 in place. During this procedure,
the physician may check the color or other marking on the top and
bottom sides 12, 14 of the implant 2 or the sheaths 46, 46', 46''
to ensure that the tape is not twisted. If necessary, the physician
may trim one or both fixation elements 16 to adjust the length of
the implant.
The physician now uses forceps to separate and remove the plastic
sheaths 46, 46', 46'' that cover the top and bottom sides 12, 14
of the tape 4. The exposed tape is left implanted in the patient
so that, over time, fibroblasts will proliferate and grow into the
tape for securing the tape in the surrounding tissue. The fixation
elements 16 fulfill their purpose for temporarily securing the implant.
After absorption of the ETHISORB, the complete mesh length (including
the parts in between the fixation elements) will have in-growth
into surrounding tissue, leaving the implanted tape to provide support
for the urethra 56.
Referring once again to the embodiments of FIGS. 10, 10a and 14,
another embodiment of an inserter particularly suited for use with
the implants of the present disclosure is shown further in FIGS.
12-14. The inserter 100 preferably includes a first inserter device
102 having a contour or the like (see FIG. 13) that is particularly
suited to substantially follow the desired insertion path as will
be described further below. In the illustrated embodiment, the inserter
includes a distal end region 103 including a tissue penetrating
distal tip 104. The tissue penetrating distal tip preferably includes
a cutting edge as opposed to a blunt edge. The first inserter device
102 includes a substantially planar portion 108, and a proximal
end region 106 including a substantially curved portion 110. The
substantially planar portion preferably has a length 1.sub.1 of
approximately 1.2 inches, and a width of approximately 0.32 inches.
Further, the curved portion 110 preferably has a length l.sub.2
of approximately 1.5 inches over approximately 50 degrees. Preferably,
the substantially planar portion is tangent to the curved portion
110, and a substantially straight proximal portion 113 of the first
inserter device is position approximately 40 degrees to the tangent
of the curved portion 110.
In the illustrated embodiment, the inserter also includes a stiffening
element 116 that is coupled to and preferably has a substantially
complementary periphery to the substantially planar portion of the
first inserter device. The stiffening element provides additional
stiffness to the inserter in the area to which the implant is secured
as will be described in greater detail below. The stiffening element
preferably is spaced slightly apart from the first inserter device,
on the order of approximately 0.006 inches, by a plurality of small
protrusions 130 or the like on either the inserter device or the
stiffening element in order to enhance the efficiency and effectiveness
of gas sterilization procedures by allowing sterilization gases
to more freely flow between the parts. This stiffening element is
a thin hardened material having an outer cutting edge 105, and a
width w.sub.1 that is slightly greater than that of the first inserter
device 102, preferably on the order of 0.015 inches wider.
In the illustrated embodiment, the stiffening element also includes
a first pass through element 132 that preferably is a spring type
element. The first pass through element has a front portion 115
and a rear portion 117 (see FIGS. 13 and 14), both of which preferably
extend upward substantially perpendicularly from the stiffening
element. As will be described further below, when an implant is
secured to the inserter, the first pass through element extends
at least partially up through an aperture in the implant, so that
the front portion 115 prevents rearward movement of the implant
relative to the inserter and the rear portion 117 prevents forward
movement of the implant relative to the inserter. Further, when
an implant is secured to the inserter, the spring type nature of
the first pass through element biases it to return to a position
that is more flush with the inserter. Thus, when the implant holding
element 118 is retracted (as described below), the implant is more
easily released. Finally, the rear portion 117 preferably has a
length such that it fits within the thickness or profile of the
inserter after the implant is released so that is does not snag
or otherwise catch on tissue as the inserter is removed from the
body following placement of the implant.
The inserter 100 further includes an implant holding element 118
that is movably coupled to the inserter device in an area towards
the proximal end of the inserter device, such that it can be moved
relative to the first inserter device as indicated by the arrow
shown in FIG. 13. The purpose for this will become apparent from
the further description below. For example, in the illustrated embodiment,
the implant holding element 118 is comprised of single and double
wire sections, which are held in place at multiple points. In the
present embodiment, these multiple points include capture element
122, pass through elements 132, 114, and finger pad 140. Preferably,
the finger pad 140 includes a projection 190 that extends between
the two wires 191a, 191b, and acts as a stop against the portion
at which the two wires come together 192 to limit retraction of
the implant holding element.
The distal end 120 of the implant holding element is removably
coupled to the first inserter device, preferably by being received
by a capture element 122 at the distal end of the inserter. By manipulation
of the implant holding device by a user, however, the distal end
of the implant holding element can be subsequently released from
the capture element. In particular, movement of the implant holding
device in the direction of the arrow shown in FIG. 13 will move
the implant holding device to a second position shown in FIG. 12a
wherein the implant holding element does not extend through the
pass through element and is not received within the capture element.
In this second position it also will not extend through the implant,
thereby releasing the implant from the inserter device as will be
readily understood by the further description below.
In the illustrated embodiment, the capture element 122 projects
upwardly from a top surface of the stiffening element, and has an
aperture 124 therein dimensioned to receive the distal end of the
implant holding element. The capture element 122 also serves a second
function in that it provides a buffer for the implant as it is inserted.
Although this is a preferred embodiment, those skilled in the art
will readily recognize that various forms and configurations for
this capture element are possible so long as it serves the purpose
of removably receiving the distal end of the implant holding element.
The inserter also preferably includes one or more pass through
element (i.e., 132, 114) projecting upwardly from its top surface,
and including one or more openings (i.e., 134, 119) therethrough.
The openings may be of any configuration or shape so long as they
allow the implant holding element to pass therethrough as shown
best in FIG. 14. This feature at least partially maintains the position
of the implant holding element relative to the inserter. Although
the illustrated pass through elements are formed integral with the
inserter, any pass through element suitable for at least partially
maintaining the position of the capture element relative to the
inserter could be used, such as suture loops or the like.
As indicated, the presently described inserter is particularly
suited for use in conjunction with an implant similar in construction
to that described in connection with FIG. 10, but having fixation
elements 141 of the configuration shown in FIG. 14, which includes
either substantially flat side edges 195a, 195b, or rough cut side
edges as described above. In a preferred embodiment, the outermost
width w.sub.2 of the implant relative to the outermost width w.sub.1
of the inserter has a ratio of approximately 1.4:1. This ratio is
preferred to achieve a balance between insertion forces and user
control as the implant is inserted into the connective tissue as
described below. Lower and higher ratios offer different results
depending on surgical needs and/or the type of tissue being penetrated.
For example, lower ratios such as between 0.7 and 1.4 can increasingly
reduce the insertion force and decrease the frictional forces of
the implant on the surrounding tissue. These lower ratios, however,
may offer less user control. Higher ratios, such as between 1.4
and 2.8 can increasingly raise the insertion force if used in tough
tissue, but may not increase the insertion force in soft tissue.
Preferably, each of the fixation elements 140 are secured to the
distal end region of the inserter device via the implant holding
element 118 as shown. In the illustrated embodiment, the implant
holding element 118 extends along and substantially adjacent to
the top surface 119 of the first inserter device until it reaches
the substantially planar region. At some point along the substantially
planar region it begins to extend away from the first inserter device
so as to leave a space therebetween as shown in FIG. 13. While spaced
apart from the first inserter device, the implant holding device
passes through the aperture 134 in the first pass through element
132, with its distal end 120 subsequently being received within
the capture element 122. As shown in FIG. 14, to secure the implant
to the inserter, the implant holding element extends upwardly through
the implant before its distal end is received within the capture
element 122. Preferably, the implant includes one or more apertures
135 extending therethrough to facilitate extension of the implant
holding element through it, and to permit the pass through element
132 to extend upwardly through it as well.
According to one embodiment, the inserter 100 further includes
a gripping element or finger pad 140 or the like positioned in the
vicinity of the proximal end of the device. The gripping element
is fixedly secured to the first inserter device 102 and has any
configuration suitable to enhance gripping and manipulation of the
device. In the illustrated embodiment, the gripping element is configured
to receive a user's index finger. Additionally it has a tapered
distal end to allow easy entry as the inserter 100 is pushed into
the body. The finger pad 140 may also contains radio opaque material
commonly used in medical devices to aid in determining if a lost
or missing component has not been accidentally left in the patient.
The inserter also may include one or two protective covers (not
shown) over the cutting edge of the stiffening element to protect
against damage or injury from the cutting edge prior to insertion.
The inserter provides several distinct advantages when inserting
the implants described herein, as it allows the implant to be secured
to the insertion device in a manner that minimizes the profile of
the overall system. This is important in applications such as those
described above because it is desirable to minimize tissue trauma
other than that which is directly necessary to insert the implant.
This is also important for visualization when placing the implant,
as it is critical that the inserter minimize obstructing the surgeon's
view during implantation. Another important aspect of the presently
described inserter is that it provides a means by which to release
the implant following proper placement without further manipulation
of the implant. Further, the inserter 100 in combination with the
described implant allows for forward and reverse adjustment of the
implant before final release, and enables superior tactile feel
by the surgeon before release. This is a significant advantage in
that proper sling placement and tension can be achieved using the
inserter device, and once this proper placement is achieved the
implant is released without further movement. This is contrary to
presently existing sling implants, where the mesh is initially implanted,
then subsequently adjusted by pulling on the ends or center of the
sling. Finally, the inserter device is designed so that it is not
situated between the implant and the urethra (as compared to an
insertion device that might "sandwich" the mesh between
two opposing components) during placement of the implant, which
has advantages with regard to proper positioning of the implant
and visualization.
Another advantageous feature of the inserter of the present invention
is that at least the cross-section of the curved portion 110 of
the first inserter device has a substantially "v" shaped
configuration 151, as can best be seen in FIG. 15b. This "v"
shaped configuration enables the width w.sub.3 of the curved portion
to be reduced relative to the outermost width w.sub.1 of the inserter,
while still maintaining sufficient strength. It has been found that
the reduced width relieves pressure against the urethra during placement
of the implant. A larger width can place pressure against the urthra
and cause a false positive, resulting in incorrect mesh placement
after the inserters are removed. In a preferred embodiment the ratio
of widths w.sub.1 to w.sub.3 is 2:1
Preferred methods for using the insertion device of FIG. 12-14
will now be described in detail with reference to FIGS. 15a-c and
16. An implant 2 having fixation elements 16 is preferably provided
to a user with two inserters such as that described above, each
secured to one end of the implant as shown in FIG. 15b. The patient
is prepped for the procedure by draining the bladder, anesthetizing
using local, regional or general anesthesia, and subsequently being
placed in the lithotomy position. Using either forceps or an Allis
clamp, the vaginal wall is grasped at each side of the urethra.
A sagital incision about 1.5 cm long, starting approximately 1.0
cm from the external urethral meatus, is then made using a scalpel
or the like. The incision will cover the mid-urethral zone and will
allow for subsequent passage of the implant. Then, with a small
pair of blunt scissors, two small paraurethral dissections of approximately
1.0 cm are made.
The proximal end 106 of one of the inserters is then grasped using
any standard needle driver or holder 150 or the like, clamping over
the holding element 118. For the "U" placement the distal
end 108 of the inserter device is then oriented in approximately
the 11 o'clock position towards the ipsilateral shoulder. With an
index finger on the finger pad, the first 152 inserter and attached
implant is inserted through the vaginal incision and first pre-dissected
paraurethral dissection as shown in FIG. 15a, with the distal end
of the insert device remaining in close contact with the inferior-posterior
aspect of the pubic bone so that the implant is inserted into the
connective tissue of the urogenital diaphragm. Insertion should
stop when the insertion device is firmly in the connective tissue
(approximately 4 cm from the distal end of the fixation element)
at the lower edge 58a of the pubic bone 58 in the vicinity of the
pubic synthesis 59 as shown in FIG. 15a. The needle driver/holder
is then uncoupled from the first inserter and coupled with the second
inserter 154 in the same way. The process is then repeated on the
other side of the urethra 156, leaving the insertion devices/implants
as shown in FIG. 15b. The tape 4 should be placed tension free under
the mid-urethra. Adjustments can be made as needed by further insertion
or retraction with the first 152 or second 154 inserters. The implant
is then released from both the first 152 and second 154 insertion
devices by pulling on the respective implant holding elements 158,160
as shown in FIG. 15c, rather than the mesh as is the case with other
known devices. The insertion devices are removed and the incision
closed, thereby completing the procedure.
According to another preferred method, the implant can be placed
in a more lateral position as shown in FIG. 16, know to those skilled
in the art as the "hammock" position. The procedure is
substantially the same as that described above, except that the
first inserter 152 is oriented in approximately the 9 o'clock position
or parallel to the floor at an angle of approximately 45 degrees
from the midline, towards the ischiopubic ramus. The distal end
of the insertion device is inserted in close contact with the bone,
but towards the obturator internus muscle, within which it is firmly
secured. Adjustment is done with the inserter 100, not by pulling
on the mesh.
The implants described herein may be advantageously implanted in
a patient without the use of needles that pass through the whole
body and without the need to form incisions in the abdominal wall,
large pre-dissected tracts, or upper leg of the patient, and further
without the need for bone anchors of the like. Not only is the procedure
less emotionally traumatic to the patient than conventional procedures
employing elongated curved needles, or hooked device that are used
to snag and drag the mesh through the body, but also less invasive,
as no incisions to the abdominal wall or upper leg of the patient
are required. Because the actual implant of the present invention
is smaller than conventional implants, this can potentially result
in less surgical complications, less mesh rejections, and/or less
mesh infections, and a shortened surgical procedure.
With the "U" implant placement of the present invention,
the surgical implantation procedure may be performed on an outpatient
basis under local, regional, or general anesthesia. Also, the procedure
for implantation requires the use of a cystoscope, although the
passage has less risk, as with all surgical procedures that pass
near a structure there is always a risk of injury. The safety of
the patient is further improved during the surgical implantation
procedure, as there is less chance for complications due to the
fact that there is no need to direct the "U" implant placement
if done properly does not travel near the bladder or bowel or any
large vessels as devices minimally invasive placement is intended
to be at the lower edge of the pubic synthesis in the connective
tissue near the pubic bone.
The "hammock" placement may similarly be performed on
an outpatient basis under local, regional, or general anesthesia.
The safety of the patient is even further improved over the "U"
during the surgical implantation procedure, as there is no risk,
if done correctly, to the bladder or bowel or any large vessels
since the device path is not into the space of retzius. Additionally,
the present invention offers yet further safety to currently known
"hammock" type procedures that pass by or near the obturator
bundle, which contains the nerve and artery. The implant of the
present invention is preferably affixed into the internous muscle
and it is not large enough to pass near the obturator bundle.
As indicated previously, although the present invention has been
described in detail in relation to a sub-urethral tape, the invention
is not so limited. The fixation elements described above can be
incorporated to serve as fixation points for any type of mesh used
in surgical procedures, such as pelvic floor repair or hernia repair,
or plastic surgery, or restructuring of tissue. For example a mesh
70 such as shown in FIG. 11 (the shape is for illustrative purposes
only, as any shaped mesh can be used) can incorporate one or more
connection regions 72 to which fixation elements 16 can be secured.
In the case of pelvic floor repair, for example, the mesh could
be sized and shaped to treat a cystocele, with the mesh being secured
in place using the fixation elements in a manner similar to that
described above. For any and all plastic surgery used to change
tissue position, for example, the device may look similar to the
present invention and the insertion device shape, any width ratios
of the inserter to implant, use of a covering, connection method
and size may be altered to suit to th surgical application being
attempted.
Although illustrative embodiments of the present invention have
been described herein with reference to the accompanying drawings,
it is to be understood that the invention is not limited to those
precise embodiments and that various other changes and modifications
may be effected herein by one skilled in the art without departing
from the scope or spirit of the invention, as is limited only by
the appended claims. |