Note: Descriptions are shown in the official language in which they were submitted.
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DOUBLE-L~TC~ED PLASTIC LIGATIN~ CLIPS
BACKGROUND OF THE INVENTION
The present invention relates to hemostatic clips and clip
appliers, and, more particularly, to hemostatic clips
fabricated from absorbable or nonabsorbable polymeric
materials and to instruments for applying such clips to
blood vessels and the like.
Hemostatic clips are utiliæed in surgical procedures to
close severed blood vessels and other small fluid ducts.
In the past, hemostatic clips have been narrow U-shaped or
V-shaped strips formed of tantalum or stainless steel
which are capable of being deformed and possess sufficient
strength to retain the deformation when clamped about a
~ blood vessel. The clips are generally applied using a
forceps-type device having jaws channeled or otherwise
adapted to hold the open clip. Representative hemostatic
clips and appliers of the prior art are best illustrated
in U.S. Patents Nos. 3,867,944; 3,631,707; 3,439;523;
3,439,522; 3,363,628; 3,312,216; and 3,270,745.
It has been suggested in the prior art, as in u.l. Patent
~ 25 No. 3,439,523, for example, that hemostatic clips might be
! formed of inexpensive plastic or materialq w~hich are
slowly absorbable in the body. Unfortunately, convention-
al U- and V-shaped hemostatic clips do not possess the
required strength or deformability when constructed of
known plastic materials to be successfully clamped about a
blood vessel. Thus, although the need and desirability of
providing inexpensive plastic ligating clips of both
absorbable and nonabsorbable materials has been recogni~ed
for over ten years, there has been no practical way to
satisfy this need.
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U.S. 3,926,195 describes a small, plastic clip designed
for the temporary or permanent close of the oviduct and
vas deferens in humans. These clips preferably have a
clamping surface of from 6 to 10 mm in length and 3 to 6
mm in wid~h. The size of such clips are accordingly
considerably larger than is desirable for hemostatic
clips. Additionally, clips of U.S~ Patent No. 3,926,195
require the use of several complex tools to apply the
clips which are acceptable for the purposes described in
the reference but would be unacceptable in a surgical
procedure requiring the rapid placement of a large number
of hemostatic clips to stem the flow of blood from severed
vessels.
It is accordingly an object of the present invention to
provide a plastic ligating clip effective for clamping off
small blood vessels and other fluid ducts in the body. It
is a further object of this invention to provide plastic
ligating clips of b,oth absorbable and nonabsorbable
materials. It is yet a further object of this invention
to provide plastic ligating clips which are quickly and
easily applied to severed blood vessels and other fluid
ducts with a single forceps-type instrument as used in
applying meta-llic clips.
! 25
SUMMARY
.
The ligating clips of the present invention comprise two
hinged leg members which interlock at both ends when the
clip is closed. The ~irst leg is configured as an open
oval having an elongated vessel clamping portion termin-
ating at each end in a return bend. The second leg is
configured to conform to the interior of said oval. The
two leg members are conne~cted at one end by an integral
molded hinge extending from the end of the first leg
member to a point on the second leg member adjoining
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said end of first leg member when the clip is in a closed
configuration.
The sharp return bend at the distal or free end of the
first leg forms a defiectable hook member. The distal end
of the second leg is adapted to deflect and engage said
hook member when the clip is closed by pivoting the two
legs about the hinge point.
The proximal or hinged end of the first leg also forms a
hook member. The proximal end of the second leg is
adapted to rotate into and engage this hook member when
the clip is closed.
The clip is provided in an initially open configuration
with the axis of the legs at approximately right angles.
- The open clip is optionally provided with means for
maintaining the clip in an open position until the clip is
extentionally closed, such as a thin web extending from
the proximal end of t~le second leg to a near point on the
interior surface of the first leg, which web is readily
sheared when a closing force is applied to the cl`ip.
I
The open clip is positioned over the vessel to b ligated
with the vessel approximately centered in the oval of the
first leg. The second leg is thereupon pivoted about the
hinge point until the ends of the second leg are engaged
by the hook members of the first leg with the vessel
securely compressed between the two leg members. A
forceps-type ligating clip applier is useful for position-
ing and closing the clip.
The clip of the present invention is unique in that once
closed, the clip is mechanically locked on both ends, and
security of the clip does not depend on the integrity of
the hinge element which is the weakest part of the clip.
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The clips of the present invention are formed of any
suitable, biocompatible polymer by extrusion, injection
molding, or other conventional fabrication process. The
polymer may be an absorbable material such as homopolymers
or copolymers of lactide, blycolide, or p-dioxanone, or a
nonabsorbable material such as nylon or polypropylene.
According to a further broad aspect of the present inven-
tion there is provided a hemostatic clip comprising first
and second leg members. Each leg member has an elongated
vessel clamping portion in opposition to a vessel clamping
portion of the other leg member. The first leg member
terminates at each end in a return bend forming a hook
member portion. The second leg memher terminates at each
end in a configuration adapted Eor engagement by the hook
members of the first leg. One of the hook members of the
first leg member is an extension of one end of the second
leg mem~er and forms a resilient hinge therewith to perma-
nently join the first and second leg members. The first
and second leg members are pivoted about the hinge means
from an open posltion to a closed position with the end,s
of the second leg member being engaged by the corresponding
hook members of the first leg member as the leg members are
pivoted to a closed position.
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DESCRIPTION _F DRAWINGS
FIGURE 1 is a greatly enlarged view in perspective of a
surgical clip according to the present invention.
FIGURE 2 illustrates the clip of FIGURE 1 clamped about
a blood vess~l.
FIGUR~ 3 illustrates a forceps-type applier useful with
the clips of the present invention.
FIGURE 4 illustrates the open clip of FIGURE 1 retained
in the jaws of a forceps-type clip applier.
FIGURE 5 illustrates the clip of FIGURE 4 closed and
locked over a blood vessel in the jaws of the applier.
FIGURE 6 illustrates an open clip of a modified design
retained in the jaws of a forceps-type clip applier.
DESCRIPTION OF PREFERRED EMBODIME~T
Referring now to FIGURE 1, there is illustrated hemostatic
clip 10 constructed of two leg members 11 and 12 connected
at the proximal ends thereof by hinge section 13. Leg 11
terminates at the distal end thereof in a return bend
forming hook member 14 having inner face 15 substantially
parallel to inner face 16 of leg 11. Leg member 12
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terminates at the distal end in end face 19 which joins
inner face 18 o~ leg 12 through radial surface 17. End
face 19 extends to outer surface 20 which is substantially
parallel to surface 18. The :Length of surface 20 is sub-
stantially equal to the length of surface 15 to provide
secure latching of the clip as hereinafter described.
At the proximal or hinged end of the clip, leg 11 termin-
ates in a return bend forming hook member 21 having an
inner face 22 substantially parallel to inner face 16.
Leg 12 terminates in radial surface 23 extending to outer
surface 24 which is substantially parallel to inner sur-
face 18. Surfaces 22 and 24 are of substantially equal
lengths and are separated by cylindrical relief bore 25
defining hinge 13.
As illustrated in FIGURE 1, clip 10 includes web 26
extending from the proximal end of leg 12 to the nearest
point on surface 16 of leg 11 when legs 11 and 12 are at
- 20 substantially right angles. Web 26 is an optional
structure which functions to stabilize the clip in its
open configuration until the web is sheared by a closing
force deliberately applied to the clip.
I
The length and width of faces 16 and 18 are substantially
equal, and face 15 of haok 14 is spaced from face 16 of
leg 11 by a distance corresponding to the thickness of leg
12 between the plane of face 18 and surface 20. When legs
11 and 12 are pivoted about hinge 13 to bring faces 18 and
16 into opposition, hook 14 is deflected by surface 19 of
leg 12 until the distal end of leg 12 snaps under hook 14
and is thereby locked in place. Simultaneously, the
proximal end of leg 12 rotates about hinge 13 to engage
hook 21 of leg 11 with surfaces 22 and 24 in contact. Web
26, if present, is sheared during closure. The proximal
end of the clip is thereby mechanically secured by a hook
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and latch interaction comparable to that securing the
distal end of the clip. The end face of hook member 14 is
preferably beveled as illustrated in FIGURE 1 to facili-
tate deflection of the hook to allow passage of leg 12
during clip closure.
The configuration of the clip when closed over a tubular
vessel as illustrated in FIGURE 2 wherein surfaces 16 and
18 of the clip engage and compress vessel 32 to close the
lumen thereof. Surfaces 16 and 18 may be smooth as illus-
trated in F-IGURE 1, or may be provided with ridges or
grooves to increase vessel holding power. Hinge 13 is
seen to extend from the end of hook 21 to a point on leg
member 12 adjoining the end of hook 21 when the clip is in
a closed position.
~ Referring again to FIGURE 1, leg 12 is provided with
applier gripping means near the distal end thereof in the
form of channel 27 which forms ridges 28 and 29 extending
20 across the width of the clip. Leg 11 is similarly pro-
vided with applier gripping means in the form of ridges 30
and 31 near the distal end thereof. The function of these
structural features in positioning the clip in the applier
i ¦ and applying the clip to the vessel being ligated is more
25 fully described hereinafter in regard to FIGURES 4 and 5.
FIGUR~ 3 illustrates a forceps-type ligating clip applier
40 comprising two ring handle members 41 and 42 crossing
at hinge point 43 and maintained in a normally open
30 position by spring 46. Handle 41 extends beyond hinge 43
forming jaw member 44 while the extension of handle 42
forms jaw member 45. Pin 38 extends from handle 42 into a
blind slot 39 in handle 41 and limits the maximum opening
of jaws 44 and 45 to that required to accommodate the open
35 clip.
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FIGURE 4 illustrates the detail of the construction of
jaws 44 and 45 of applier 40 and the interaction of the
jaws with the clip of FIGURE 1. Jaws 44 and 45 are of
identical design and are provided respectively with
channels 47 and 48 extending rearwardly from the tips of
the jaws. The width of each channel is sufficient to
accommodate the width of the clip, and each channel is
provided with gear-like teeth 49 and 50 across the bottom
of the channel over an area extending rearward from the
tips of the jaws. The size and spacing of channel teeth
49 and 50 correspond to the size and spacing of the
corresponding ridges on the clip, and when the open clip
is held in the applier, the ridges of the clip mesh with
the teeth of the applier as illustrated in FIGURE 4.
Since the jaws of the applier have identical structure,
there is no need to orient the applier to the clip when
loading or using the applier.
Clip 10 is initially loaded in applier 40 in the normally
open position as illustrated in FIGURE 4. After moving
the jaws of the applier and the clip into position over
the vessel to be ligated, the jaws of the applier are
closed and the clip is locked in position over thle vessel
as illustrated in FIGURE 2. As the jaws~of thel applier
are closed, the legs of clip 10 rotate in the channels of
the jaws until the distal end of leg 12 is engaged by hook
member 14. Once the clip is fully closed and locked onto
the vessel as illustrated in FIGURE 5, the jaws of the
applier are opened and the applier withdrawn from the site
to be reloaded with another clip.
Referring now to FIGURE 6, there is illustrated another
embodiment of a clip and applier in accordance with the
present invention wherein legs 11 and 12 are each provided
with a channel 52 extending across the width of the clip
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near the distal end thereof. Jaws 44 and 45 of the
applier are provided with corresponding raised bosses 51
adapted to engage channels 52 when the open clip is
positioned between the jaws. The channel of jaw 45 is
additionally recessed at 53 to accommodate hook 14 of the
clip when the clip is closed between the jaws. As illus-
trated, the channel of jaw 44 is similarly recessed to
eliminate the necessity for orienting the applier to the
clip .
Although the illustrations and description have been
limited to certain specific embodiments of the ligating
clip of the present invention, many variations in clip
design will be apparent to those skilled in the art and
are contemplated in the scope of the present invention.
For example, the gripping means between the applier jaws
and the clip, i.e., the teeth and ridges of FIGURE 4 or
the boss and channels of FIGURE 6 are preferred but
optional and may be omitted. The clips may be fabricated
with a smooth outer surface and the jaws of the applier
may have smooth channels to accept the clip. Addition-
ally, the channels of the applier may be contoured to the
outer configuration of the clip in order to orient and
secure the clip between the jaws. These and other
modifications in the configuration of the clip may be
employed without departing from the spirit and scope of
the pr-esent invention.
The clips of the present invention may be constructed in
various sizes according to their intended function.
Hemostatic clips are typically less than 6 mm in length,
about 1.5 mm in width, and have a vessel clamping surface
about 3 mm in length. The dimensions of the clip may be
reduced by about 50 percent for certain applications in
microsurgery. Larger clips for special hemostatic
applications and other functions such as closure of
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oviducts or vas deferens may have dimensions of about
double those of a typical hemostatic clip. The various
sizes of clips are preferably matched with individual
appliers having jaws tailored to the size of the clip for
best performance.
The clips of the present invention are conveniently molded
of biologically acceptable plastic materials which may be
! absorbable or nonabsorbable. Preferred absorbable poly-
mers include homopolymers and copolymers of glycolide,
lactide, and ~-dioxanone. Preferred nonabsorbable poly-
mers include nylon, polyester and polypropylene. All
these materials have been demonstrated to be biologically
acceptable when used as sutures or other implantable
medical devices. The clips may also be cast or machined
from solid polymeric materials or from metals such as
aluminum, magnesium, stainless steel, tantalum, and
various alloys of these, some of which may also be absorb-
able in biological tissue.
