U.S. patent application number 10/365481 was filed with the patent office on 2003-07-24 for suture retention device.
Invention is credited to Cartier, Raymond, Paolitto, Anthony, Valentini, Valerio.
Application Number | 20030139776 10/365481 |
Document ID | / |
Family ID | 4162620 |
Filed Date | 2003-07-24 |
United States Patent
Application |
20030139776 |
Kind Code |
A1 |
Paolitto, Anthony ; et
al. |
July 24, 2003 |
Suture retention device
Abstract
The present invention provides a tissue retractor (2) for
displacing body tissue during surgery consisting of a tissue
piercing member such as a surgical needle (20), a wire-like
filament such as a suture line (23) affixed to the surgical needle
(20), a fixed element such as an anchoring port (90) being
associated with a stable surgical platform such as a sternum
retractor (1), and a movable element such as an anchoring plug (25)
cooperating with anchoring port (90) to engage a portion of suture
line (23) after the suture line (23) is threaded through the body
tissue with the surgical needle (20) and after the suture wire (20)
is tensioned to effect a predetermined displacement of the body
tissue. The predetermined displacement of body tissue is maintained
by retention of the engaged portion of suture line (23) by the
fixed anchoring port (90) and the movable anchoring plug (25).
Inventors: |
Paolitto, Anthony; (St.
Leonard, CA) ; Valentini, Valerio; (Montreal, CA)
; Cartier, Raymond; (Montreal, CA) |
Correspondence
Address: |
Anthony Paolitto
CORONEO Inc.
Suite 514
9250 Avenue du Parc
Montreal
QC
H2N 1Z2
CA
|
Family ID: |
4162620 |
Appl. No.: |
10/365481 |
Filed: |
February 13, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10365481 |
Feb 13, 2003 |
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09762437 |
Apr 10, 2001 |
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6547725 |
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09762437 |
Apr 10, 2001 |
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PCT/CA99/00740 |
Aug 10, 1999 |
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Current U.S.
Class: |
606/232 |
Current CPC
Class: |
A61B 2017/0496 20130101;
A61B 17/0293 20130101; A61B 2017/06052 20130101; A61B 17/0487
20130101; A61B 2017/045 20130101; A61B 2017/0243 20130101; A61B
17/06061 20130101; A61B 17/0206 20130101 |
Class at
Publication: |
606/232 |
International
Class: |
A61B 017/04 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 10, 1998 |
CA |
2,242,295 |
Claims
1. A suture retention device attachable to a surgical platform for
retracting a surgical incision, said suture retention device
comprising: a first member; a second member; said first member and
second members configured to create a retention slot for receiving
a surgical suture; wherein said first and second members cooperate
to frictionally retain said surgical suture relative to said
surgical platform when said surgical suture is placed within said
retention slot.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to the field of surgical
apparatus and more specifically, to a suture and associated
anchoring mechanism for applying tissue retraction during
surgery.
BACKGROUND OF THE INVENTION
[0002] Generally, surgery requires an incision through a patient's
skin, underlying muscle and tissue to expose the underlying body
organ or anatomical tissue which is in need of the particular
surgical intervention. In certain types of surgery such as cardiac
surgery for instance, the patient's bone structure may also be
incised and retracted. This is the case with a midline sternotomy
incision which incises the patient's sternum and retracts the
ribcage, or in situations where bone structure is spread apart
without incision thereof as with an intercostal thoracotomy
incision in which two adjacent patient ribs are spread apart in
order to expose the underlying body organ, namely the patient's
heart.
[0003] To obtain and maintain a surgical window or opening onto the
underlying body organ or tissue in relation to which the surgical
intervention will take place, abdominal or thoracic surgical
retractors are used subsequent to the initial incision to spread
the incised body tissue. Surgical retractors exist in many sizes
and shapes and have been present since the dawn of surgery. Most
known retractors have an elongate rack bar and two retracting arms,
namely a fixed retracting arm and a movable retracting arm. Both
arms typically extend in a direction normal to the rack bar. The
movable arm can be displaced along the rack bar, and relative to
the fixed arm, by using a crank to activate a pinion mechanism
which engages teeth on the rack bar. Two blades are provided,
usually disposed below the retractor arm and extending into the
surgical incision, to interface with the patient's skin and tissue
and to apply the retraction that creates the surgical window by
relative movement and an ensuing spacing apart of the two retractor
arms. The retractor blades may also engage with the patient's bone
structure during surgery that requires access to tissue or organs
contained within the patient's thorax. This is the case with
coronary artery bypass graft (CABG) surgery, where the patient's
skin and incised sternum are engaged with the blades of a surgical
retractor known as a sternum or sternal retractor. The basic
surgical approach and surgical retractor design for creating a
surgical window onto the underlying tissue and organs requiring the
surgical intervention, whereby the two or more spreader members or
retractor arms are moved apart to retract engaged tissue, have
remained relatively unchanged since the first introduction of
retractors to surgery, regardless of the type, size and shape of
the surgical retractor. The surgeon may at times place a sterile
drape, cloth, or other type of packing between the patient's
incised body tissue and the interfacing blades or other portion of
the surgical retractor.
[0004] Once the surgical window is created, the surgeon often times
will retract other internal body tissue which becomes accessible
through the surgical window, with a flexible wire-like filament
having a tissue-piercing member on one end of the wire-like
filament, such as a suture line with integral needle on one end of
the suture line. The suture line with the integral tissue piercing
needle at one end will be referred to herein as the "traditional
suture" or simply the "suture".
[0005] A standard technique for retraction of coronary tissue
during cardiac surgery has been the use of sutures, including
traction sutures and stay sutures. These sutures are well known in
the field of cardiac surgery and are available in a variety of
needle configurations, suture length and diameter thicknesses. The
sutures are generally available in kit form in disposable
sterilized packets containing a needle and a length of
filament.
[0006] Internal body tissue may be retracted for a number of
reasons during surgery, namely:
[0007] a) to improve access to the target body organ or target
organ tissue requiring the surgical intervention; this may be
accomplished by displacing or retracting surrounding internal body
tissue that may obstruct, restrict or impede surgical access, as
for instance when retracting fatty tissue;
[0008] b) to maintain access to the inside of an organ cavity or
body vessel subsequent to an incision of the organ or vessel; this
may be accomplished by retracting incised portions of organ tissue
or vessel tissue, as for instance when retracting incised portions
of the aorta to maintain access to the aortic valve;
[0009] c) to position or orient at least a portion of the body
organ; this may be accomplished through retraction of surrounding
tissue which is anatomically attached to the body organ or through
retraction of the body organ directly.
[0010] Tissue retraction is typically achieved by piercing the body
organ or body tissue with a needle at the end of a suture line,
threading a length of suture line through the pierced body tissue,
and pulling simultaneously on both resulting lengths of the suture
line; that is, the length between the pierced tissue and the free
end of the suture line, and the length between the pierced tissue
and the needle-bearing end of the suture line. Retraction loads are
imposed on the body tissue or body organ at the location where the
needle pierces and penetrates through the tissue or the organ.
[0011] In most surgical procedures, retraction is maintained by
securing the above mentioned two lengths of the suture line by
accomplishing one of the following techniques:
[0012] a) tying the free end and needle-bearing end of the suture
line to each other through another part of the patient's anatomy,
preferably remote to the location of body tissue where the surgical
intervention will take place;
[0013] b) simultaneously clamping these two lengths of suture line
to other body tissue or to the sterile cloth or packing inserted
between the surgical retractor and the patient's incised tissue
creating the surgical window;
[0014] c) clamping these two lengths to the surgical retractor with
a surgical clamp or tying the free end and the needle-bearing end
of these two lengths to each other and to a portion of the surgical
retractor;
[0015] d) clamping these two lengths with a surgical clamp and
wedging the tip or at least a portion of the surgical clamp between
the retractor and the patient's body or between the retractor and
the sterile cloth or packing placed along the surgical incision and
trapped between the retractor blades and patient's body.
[0016] The current methods described above of maintaining tissue
retraction may, in some instances:
[0017] a) be time consuming, since securing of the retraction load
through the manual tying of the suture line lengths is a multi-step
threading and knotting procedure;
[0018] b) be cumbersome due to poor access during the manual tie
down of the suture line lengths, especially in surgical
interventions when the surgical window is small;
[0019] c) not be conducive to readjustment of the magnitude of the
desired tensile retraction load on the organ or body tissue, or on
the direction of said load relative to the organ or body tissue
without having to untie and retie suture line lengths or without
having to cut the existing suture line having the undesired
retraction load and replacing it with a new suture that must again
pierce the organ or body tissue and be secured by way of one of the
methods listed above;
[0020] d) compromise the ergonomics of and the surgeon's access
into the surgical window, especially when a surgical clamp is used
to secure the two lengths of the suture line to the perimeter of
the surgical window or to a portion of the surgical retractor used
to create the surgical window, all the more when multiple suture
lines need to be secured to achieve the desired organ or body
tissue retraction;
[0021] e) hinder or restrict the readjustment of the surgical
window opening through the opening or closing of the surgical
retractor, if the lengths of the suture line are tied to the rack
bar of the surgical retractor, or hinder the deployment or
readjustment of peripheral surgical devices that are mounted or
need to be mounted on the spreader arms of the retractor.
[0022] Generally, adjustment of the desired tensile retraction by
cutting an existing suture line and repiercing a new suture line is
not desirable. First, the process of placing a suture requires
considerable manual dexterity, at times requiring the help of an
assistant. The process is therefore tedious and time consuming.
Second, a repiercing of the internal body tissue or body organ with
a subsequent suture tends to increase the likelihood of inducing
tissue trauma or tissue tearing which may have to be surgically
repaired.
[0023] More recently with the advent of minimally invasive surgical
techniques, laparoscopic approaches have been developed.
Consequently, the surgical access windows into the patient's
abdomen or thorax have become smaller. However, internal tissue
retraction through a suture (suture line with a tissue piercing
needle attached to at least one end) remains a requirement in
certain types of surgical interventions. This tissue retraction
with suture tends to generally be more difficult due to the smaller
access through a laparoscopic entry relative to the larger surgical
access window obtained through the traditional retracted incision
entry.
[0024] Although the principles of this invention may be applied to
many types of surgeries requiring tissue retraction by the
application and maintenance of a tensile load on a suture, the
examples will focus on cardiac surgery; and more specifically, on
CABG surgery performed on the beating heart. In addition, although
the examples will refer to retraction of internal body tissue, the
concepts and principles may also be extended to external body
tissue, as those skilled in this art will appreciate.
[0025] CABG surgery has been traditionally performed with the
support of the cardio-pulmonary machine, whereby the patient's
blood is oxygenated outside the body through extracorporeal
circulation (ECC). This allows the surgeon to manipulate and
operate on a perfectly still heart. During traditional CABG
surgery, the surgeon or assistant can manually position and orient
the arrested heart for best access to the target artery requiring
the bypass graft.
[0026] Recently, in an aim to render CABG surgery less invasive to
the patient, beating heart CABG surgery is being developed whereby
ECC, one of the most invasive aspects of cardiac surgery, is
eliminated and coronary artery revascularization is performed
directly on the beating heart. One of the challenges in performing
beating heart CABG surgery lies in positioning and orienting the
beating heart in order to obtain access to the inferior and
posterior artery beds, while tending to minimize physiologically
undesirable effects such as hemodynamic instability, arrhythmia, or
a precipitous drop in arterial pressure, that may occur as a result
of such manipulations. In traditional CABG surgery the heart is
arrested and therefore heart manipulations are well tolerated.
[0027] During CABG surgery or beating heart CABG surgery, the
pericardium, namely the membranous sac in which the heart and the
commencement of the major blood vessels connecting with the heart
are contained, is generally incised and unraveled to expose at
least a portion of the heart surface which is to receive the bypass
graft. The pericardium tissue, unlike the heart, is not beating and
can be separated from the heart surface except in some locations
where it is anatomically attached to the heart. Thus, it is
surgically possible to position or orient the heart by manipulating
the pericardium tissue to which it is attached. In beating heart
CABG surgery, it may be desirable to position and orient the
beating heart through retraction of the pericardium tissue to
obtain access to the inferior and posterior coronary artery beds.
The likelihood of inducing trauma to the beating heart tends to be
reduced, and the physiologically undesirable effects mentioned
above tend to be reduced, since direct contact with the beating
heart is avoided and the manipulations are achieved through
retraction of the pericardium tissue which, although incised
remains anatomically attached to the beating heart in certain
locations.
[0028] Based on the foregoing, it would, therefore be advantageous
to provide a suture with an integral anchoring member that may be
inserted into an anchoring port of a stable platform (such as a
surgical retractor) to tend to achieve and maintain the desired
tissue retraction load on the organ or body tissue of the patient
in a relatively quicker and more convenient fashion than some of
the prior art methods described above.
[0029] Alternatively, based on the foregoing, it would also be
advantageous to provide a surgical retractor configured with an
integral suture anchoring mechanism or add-on suture anchoring
mechanism capable of engaging a traditional suture (namely, as
explained above, a suture comprised of a suture line with tissue
piercing needle attached to at least one end) to tend to achieve
and maintain the desired tissue retraction load on the organ or
body tissue of the patient in a relatively quicker and more
convenient fashion than some of the current methods described
above.
[0030] Thus it is one of the objects of the present invention to
aim to reduce deployment times associated to the placement of
tissue retraction sutures and to facilitate the securement thereof
during surgery.
[0031] It is another object of the present invention to provide a
tissue retractor comprising a suture line allowing the retraction
of body tissue or body organs during the surgical intervention that
aims to eliminate the operation of manually tying suture line
lengths to one another through a multi-step threading and knotting
procedure in order to achieve the said retraction.
[0032] It is another object of the present invention to provide a
tissue retractor comprising a suture line allowing the retraction
of internal body tissue or body organs during the surgical
intervention which permits the readjustment of the retraction force
applied by said suture line to the internal body tissue, either in
magnitude or in direction, without requiring the severing or
disposal of said suture line and without the removal of said suture
line from internal body tissue.
[0033] These and other objects of the present invention will become
apparent from the description of the present invention and its
preferred embodiments which follows.
SUMMARY OF THE INVENTION
[0034] According to one broad aspect of the present invention,
there is provided a tissue retractor for displacing body tissue
during surgery, the tissue retractor comprising a surgical tissue
piercing member; a suture line affixed to the surgical tissue
piercing member; a fixed element, the fixed element being
associated with a stable surgical platform; a movable element, the
moveable element cooperating with the fixed element to engage a
portion-of the suture line after the suture line is threaded
through the body tissue with the surgical tissue piercing member
and after the threaded suture line is tensioned to effect a
predetermined displacement of said body tissue; and wherein said
perdetermined displacement of said body tissue is maintained by
retention of the engaged portion of the suture line by the movable
element and the fixed element.
[0035] In some surgical interventions, the foregoing features
contribute to attempt to position and orient the beating heart
through retraction of the incised pericardium tissue during beating
heart CABG, while tending to minimize the likelihood of inducing
physiologically adverse effects such as hemodynamic instability,
arrhythmia, or a precipitous drop in arterial pressure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0036] For better understanding of the present invention and to
show more clearly how it may be carried into effect, reference will
now be made by way of illustration and not of limitation to the
accompanying drawings, which show an apparatus according to
preferred embodiments of the present invention, and in which:
[0037] FIG. 1A is a perspective view illustrating a tissue
retractor comprising a suture and associated anchoring mechanism
according to a first embodiment of the present invention;
[0038] FIG. 1B is an exploded view of the suture and anchoring
mechanism illustrated in FIG. 1A;
[0039] FIG. 1C is a partially assembled view of the suture and
anchoring mechanism illustrated in FIG. 1B depicting a partially
anchored suture line;
[0040] FIG. 1D illustrates a variant of the disposition of the
suture line with reference to the first embodiment of FIGS. 1A to
1C;
[0041] FIGS. 2A to 2C illustrate several variants of anchoring
members of the anchoring mechanism with reference to the first
embodiment of FIGS. 1A to 1D;
[0042] FIGS. 3A to 3C illustrate several variants of an anchoring
member of the anchoring mechanism of the first embodiment of FIGS.
1A to 1D comprising an anchoring member handle;
[0043] FIGS. 4A and 4B illustrate variants of anchoring members of
the anchoring mechanism with reference to the first embodiment of
FIGS. 1A to 1D, comprising openings therein suitable for reception
of a suture line;
[0044] FIGS. 5A and 5B illustrate a tissue retractor comprising a
suture and associated anchoring mechanism according to a second
embodiment of the present invention,
[0045] FIGS. 5C and 5D illustrate several variants of anchoring
members of the anchoring mechanism with reference to the second
embodiment of FIGS. 5A and 5B;
[0046] FIG. 6A is a perspective view illustrating a tissue
retractor comprising a suture and associated anchoring mechanism
according to a third embodiment of the present invention;
[0047] FIG. 6B is an exploded view of the anchoring mechanism
according to the third embodiment of the present invention
illustrated in FIG. 6A comprising a pinch roller member and
traction roller member;
[0048] FIG. 7A is a perspective view of a tissue retractor
comprising a suture and associated anchoring mechanism according to
a fourth embodiment of the present invention;
[0049] FIG. 7B is a top view of the tissue suture and associated
anchoring mechanism of FIG. 7A comprising a pawl-shaped lever
member;
[0050] FIG. 8A is a perspective view of a tissue retractor
comprising a suture and associated anchoring mechanism according to
a fifth embodiment of the present invention;
[0051] FIG. 8B is a side elevational view of the suture and
associated anchoring mechanism of FIG. 8A comprising a screw member
and spring-loaded washer member;
[0052] FIG. 9A is a perspective view of a tissue retractor
comprising a suture and associated anchoring mechanism according to
a sixth embodiment of the present invention;
[0053] FIG. 9B is a side elevational view of the suture and
associated anchoring mechanism of FIG. 9A comprising a swing plate
lever member.
DETAILED DESCRIPTION OF THE INVENTION
[0054] The features and principles of this invention can be
applied, in whole or in part, to many types of surgical procedures
including those which rely on surgical retractors to create and
maintain a surgical window into the patient's incised skin for
access into the patient's abdomen or thorax, and those which rely
on laparoscopic entry ports into the patient's skin to gain such
access. The description of the preferred embodiments will be
illustrated with respect to sternum retractors used in cardiac
surgery, for instance those used to perform traditional CABG
surgery with ECC, beating heart CABG without ECC, or valve surgery
through a midline sternotomy incision. However, some of the
features and principles may also apply to other types of
retractors, such as abdominal retractors and thoracic retractors
used in other types of surgical procedures. Some of the features
and principles may even apply to other substantially stable
surgical platforms which can be configured with an anchoring port
or anchoring mechanism as described and illustrated in the
embodiments herein. Such surgical platforms would include: a
surgical table, a surgical bridge or truss member attached to a
surgical table and spanning the patient or set adjacent the
patient; a surgical attachment for fixturing an instrument used in
laparoscopic surgery to a surgical table, surgical bridge or truss,
or a surgical instrument as may be used in laparoscopic surgery, or
other like platforms.
[0055] In part, the embodiments of this invention may
advantageously be applied, if desired, to the retractor described
in copending Canadian patent application Serial No. 2,216,893 filed
on Sep. 30, 1997 in the names of Cartier and Paolitto and entitled
"Sternum Retractor for Performing Bypass Surgery on the Beating
Heart", and in copending Canadian patent application Serial No.
2,232,795 filed on May 22, 1998 in the names of Paolitto et al. and
entitled "Manipulation and Adjustment of Surgical Instruments", the
contents of each of which are incorporated herein by reference.
These existing applications have been assigned to CoroNo Inc., the
assignee of the present application.
[0056] By way of a general overview and with reference to FIG. 1A,
a surgical apparatus with which the invention may be used is
comprised of two main components, a tissue retractor 2 and a
sternum retractor 1. The sternum retractor 1 is provided with a
plurality of anchoring ports 90 to receive at least one said tissue
retractor 2 in at least one said anchoring port 90, in order to
effectuate the desired tissue retraction of internal body tissue
(labelled IBT). The tissue retractor 2 is illustrated after having
pierced internal body tissue IBT, prior to its intended engagement
with the sternum retractor 1 and more specifically with one of the
anchoring ports 90 thereof. The sternum retractor 1 is illustrated
in its deployed state, thereby creating and maintaining the
surgical window (labelled SW) that provides the surgeon with access
to the patient's internal coronary organs, which include the heart,
the pericardium tissue, the aorta and vena cava, the coronary
arteries and veins, the pleurae, the thymus, and other anatomical
features, all of which are collectively and schematically depicted
as internal body tissue IBT.
[0057] The sternum retractor 1 includes four major parts: (i) an
elongated rack bar 5, (ii) a first retractor spreader arm 3 being
preferably fixed to the rack bar 5, (iii) a second retractor
spreader arm 4 being preferably movable with respect to the rack
bar 5, and (iv) an actuator 6 for effecting movement of the
retractor spreader arm 4 relative to retractor spreader arm 3.
[0058] Retractor spreader arms 3 and 4 extend in a direction
substantially transversely with regard to the rack bar 5, generally
in the same direction therefrom and in a parallel orientation with
respect to one another. The movable arm 4 can be displaced along
the rack bar 5, and relative to the other arm 3, preferably through
the rotation of the actuator 6 activated by the surgeon. The
actuator 6 is operatively connected to the rack bar 5 and to the
other spreader arm 4, and is translatable along the length of the
rack bar 5. This is preferably achieved by the engagement of a
pinion mechanism (not shown) of actuator 6 with the rack teeth 52
on rack bar 5. Two retractor blades 7 (not wholly visible in FIG.
1A) and 8 are respectively provided with the retractor spreader
arms 3 and 4, preferably disposed below the rack bar 5 when the
sternum retractor 1 is deployed on a patient. The retractor blades
7 and 8 engage with and serve to retract a portion of the patient's
incised skin, the two halves of the patient's incised sternum and
the patient's ribcage thereby exposing the coronary organs to be
operated on through the resultant surgical window (labelled SW).
The left and right sides of the retracted surgical incision
(labelled LSI and RSI respectively) are schematically illustrated
in FIG. 1A. When viewing the resultant surgical window SW from
above the patient, the retractor arms 3 and 4 of the deployed
surgical retractor 1 each have a generally arcuate orientation.
[0059] The sternum retractor 1 advantageously comprises arcuate
rails 70 and 80 along the top of arcuate retractor spreader arms 3
and 4, respectively. The rails 70 and 80 configure an inverted
T-slot arcuate passage 71 and 81, respectively, preferably
centrally located within said rails, and preferably extending
throughout the entire arcuate length of said rails. A similar
linear longitudinal rail 50, may also be configured along the top
of rack bar 5. Longitudinal rail 50 is also configured with an
inverted T-slot longitudinal passage 51, preferably extending
throughout its entire longitudinal length. These said rails form a
mounting perimeter that can advantageously serve to engage a
positioning and articulation mechanism utilized to place a variety
of heart stabilizers during beating heart bypass surgery, for
instance, as described in previously mentioned Canadian application
Serial No. 2,216,893. Alternatively, the positioning and
articulation mechanism may also be utilized to set a coronary organ
contacting member used in cardiac surgery, such as a valve tissue
retractor for example. As well, these rails can also be utilized to
engage other surgical apparatus, that may need to be secured along
the perimeter of the sternum retractor 1 during cardiac
surgery.
[0060] A plurality of slit-like channels 72 and 82 are configured
along the arcuate arms 3 and 4 and cut through the arcuate rails 70
and 80, respectively. FIG. 1A illustrates three such slit-like
channels 72 on the retractor spreader arm 3 and three such
slit-like channels 82 on the retractor spreader arm 4. The
slit-like channels 72 and 82 extend downwards from the top of the
rails 70 and 80 to a depth preferably below the entire depth of the
inverted T-slot arcuate passages 71 and 81, preferably by an amount
equivalent to the width of said slit-like channel. Similar
slit-like channels were introduced in above mentioned Canadian
patent application Serial No. 2,232,795, in order to provide
passages for the placement of sutures serving to retract body
tissue, for example pericardium tissue. The slit-like channels in
the present invention and in Canadian application 2,232,795 are
configured so that a suture line or other like wire-like filament
will not restrict or otherwise hinder the functionality of the
positioning and articulation mechanism when such mechanism becomes
engaged in said passages 71 and 81 of said rails 70 and 80,
provided the suture line or other wire-like filament is placed in
the deepest position within said slit-like channel.
[0061] The sternum retractor 1 is configured with a plurality of
anchoring ports 90, preferably disposed laterally outward away from
the perimeter delineated by retractor arms 3 and 4, and
consequently laterally outward away from the surgical window SW, in
order to aim to maximize the access and visibility into the SW. For
instance, the plurality of anchoring ports 90 can be configured
laterally inward from the retractor arms 3 and 4, or configured as
material extensions to retractor blades 7 and 8, but this would
tend to compromise the ergonomics of the surgeon's workspace and
access into the surgical window SW even though the slit-like
channels 72 and 82 may be eliminated in this alternate
configuration. It is also preferable to have each anchoring port 90
in line with each of slit-like channel 72 or 82, so that said
anchoring port can conveniently serve to secure the tissue
retractor 2 when at least a portion of the said tissue retractor is
engaged in said slit-like channel.
[0062] The tissue retractor 2 is comprised of several main parts:
(i) a tissue-piercing member such as a curved needle 20, (ii) a
wire-like filament such as a suture line 23, (iii) an anchoring
member such as anchoring plug 25, and (iv) an anchoring port 90.
The curved needle is of a substantially circular cross-section
having a sharp tip 201 suitable for piercing and penetrating body
tissue, and a substantially blunt end 202 which is preferably
integrally attached to the suture line 23 at point A. The material
of both the suture line 23 and the curved needle 20 are as per
existing suture lines and needles customarily used in surgery. The
surgeon typically manipulates the needle 20 by grasping said needle
between the jaws of a surgical needle holder, surgical clamp, or
other surgical implement routinely used in surgery for manipulating
the needle portion of traditional sutures. The anchoring plug 25 is
also preferably integrally attached to the other end of suture line
23 at point F. Depending on the size of the surgical window SW
required for the surgical intervention, the suture line 23 is of a
suitable overall length, for instance between point A and F
thereof, to permit retraction of the desired internal body tissue
IBT by securing the tissue retractor 2 to the sternum retractor 1,
in a manner that will be described in more detail below. The
anchoring plug 25 further preferably incorporates a suture-locating
slot 251 at its free end, whose function will be described in
greater detail below. The longitudinal axis of the suture-locating
slot 251 is preferably perpendicular to the longitudinal centerline
axis of the anchoring plug 25.
[0063] In this first embodiment, as further illustrated in FIGS.
1B-1D, the anchoring port 90 is illustrated as being integral with
the retractor arms 3, such as a cast boss, a brazed-on boss or a
welded-on boss. Alternatively, the anchoring port. 90 may also be a
separate component that is mechanically fastened to the retractor
arm 3 (or 4) by a variety of conventional fastening methods, such
as bolting or riveting, in a manner that renders it fixed relative
to the sternum retractor arm 3 (or 4) on which it is assembled, at
least for the duration of the surgical intervention for which
tissue retraction is performed. The anchoring port 90 in this
embodiment is a substantially cantilevered fitting 901, disposed
laterally outwards from the arcuate curvature of retractor arm 3 or
4, its top face 904 preferably having a substantially horizontal
orientation when sternum retractor 1 is deployed in the patient. An
aperture 902, preferably a through hole, is configured in the
center of fitting 901, with the longitudinal axis of said aperture
being preferably substantially vertical and substantially
perpendicular to the laterally disposed, horizontally oriented
fitting 901. Relative to the arcuate rail 70 (or 80), the top face
904 of the fitting 901 is situated below the maximum depth of
slit-like channel 72.
[0064] The geometry of the aperture 902 can take on many variants
(cylindrical aperture, conical aperture, tapered aperture,
hexagonal cross section aperture, elliptical cross section
aperture, and other geometries that will be apparent to those
skilled in the art) but in all cases will depend on the geometry of
the cooperating anchoring plug 25 which must remain secure relative
to the anchoring port 90, and retractor arm 3 (or 4) on which said
anchoring port is disposed, after the engagement of the anchoring
plug 25 into the said port 90. A chamfer-like feature 903 is also
preferably configured on the top surface 904 of fitting 901, around
the perimeter of aperture 902, to ease the entry of anchoring plug
25 into aperture 902. In this embodiment, the anchoring plug 25 is
defined by a substantially conical surface 252, truncated at the
its narrower free end by the surface defining the suture-locating
slot 251. Preferably, the cross section of aperture 902 is
progressively smaller in area, from its maximum area at the top
surface 904 to a smaller area at its maximum depth in fitting 901,
in order to promote wedging with the plug outer surface 252 when
anchoring plug 25 is inserted and engaged into said aperture. The
maximum diameter of the anchoring plug 25 is at least as large as
the minimum diameter of aperture 902 so as to result in a
substantially tight fit when said plug is engaged in said aperture.
The maximum diameter of the anchoring plug 25 is preferably only
slightly larger than the maximum diameter of the aperture 902, such
that when said plug is fully engaged in said aperture, its top face
253 is located only slightly proud from fitting top face 904, with
the result that the suture line 23 which is in tension from the
retraction load it applies to the internal body tissue IBT is
resting at the maximum depth within slit-like channel 72 in order
not to interfere with the above mentioned positioning and
articulation mechanism, or other surgical apparatus, which may be
engaged or moved through the arcuate passage 71 (or 81).
[0065] FIG. 1C illustrates a partially engaged anchoring plug 25
within aperture 902. When the anchoring plug 25 will be fully
engaged in aperture 902, the top face 253 will be substantially
coincident with top face 904, thereby downwardly situating the
length of suture line 23 between points F and D thereof such that
the length of suture line 23 passing through the slit-like channel
72 will also come to rest at the maximum depth of said slit-like
channel. This tends to ensure that the tissue retractor 2, and more
specifically its suture line 23, is maintained in close proximity
to the sternum retractor surfaces thereby aiding to improve the
ergonomics of the surgical work site. When the anchoring plug 25 is
fully engaged within aperture 902, the narrower free end of the
anchoring plug and suture locating slot 251 extend below the
fitting 901. Disengagement of the anchoring plug 25 from the
anchoring port 90 is achieved by pressing upward on the suture
locating slot 251, in a direction substantially parallel to the
longitudinal axis of the aperture 902. The concavity of the suture
locating slot 251 provides a groove for the surgeon's finger
thereby tending to improve adherence while the disengagement load
is applied. This said concavity may also be advantageously engaged
with a surgical clamp, needle holder, or other surgical implement
which may be used to apply the disengagement load.
[0066] In all the descriptions of embodiments according to the
present invention, it is assumed that once the desired tissue
retraction load is applied to the internal body tissue IBT, the
tissue-piercing point of entry into the internal body tissue IBT
(substantially coincident with point D on FIG. 1A and
tissue-piercing point of exit out of internal body tissue IBT
(substantially coincident with point C on FIG. 1A are situated
below the plane formed across the top of arcuate rails 70 and 80 of
a deployed sternum retractor 1 by at least the depth of the
slit-like channels 72 and 82.
[0067] For purposes of illustrating the principles of the present
invention, points A to F have been defined along the length of
suture line 23. Point A is the extremity of suture line 23 attached
to curved needle 201. Point F is the opposite extremity of suture
line 23 attached to anchoring plug 25 or in some embodiments of the
invention is the free end of suture line 23. Point C is the point
along the length of suture line 23 located at the interface with
internal body tissue IBT where the needle 20 exited therefrom
during deployment of tissue retractor 2. Point D is the point along
the length of suture line 23 located at the interface with internal
body tissue IBT where the needle 20 pierced and entered into said
internal body tissue IBT during deployment of tissue retractor 2.
Point B is a point along the length of suture line 23 between point
A and C to be selected for engagement with anchoring plug 25, or in
later embodiments with a portion of other anchoring mechanisms.
Point E is a point along the length of suture line 23 between point
D and F to be selected for engagement with anchoring plug 25, or in
later embodiments with a portion of other anchoring mechanisms. The
relation of each points B, C, D, or E relative to each of points A
or F is variable and arbitrary, depending in part on: the length of
suture line 23 that is threaded through the internal body tissue
IBT in a specific deployment of the tissue retractor 2; the
thickness of internal body tissue IBT pierced by needle 20 that
will contain a length CD of suture line 23 within internal body
tissue IBT after threading of a length of suture line 23 occurs;
and the portion of entire length of suture line 23 that will be
selected for anchoring and securing tissue retractor 2 into
anchoring port 90. A length AC of suture line 23 means the length
of suture line between points A and C. A segment within length AC
will mean a portion of suture line 23 between point A and point C
substantially shorter than the total length between point A and
point C.
[0068] In broad terms, a typical example of the surgical procedure
for the set-up and deployment of the surgical apparatus relating to
the present invention consists of the surgeon:
[0069] a) Grasping the needle 20 with a surgical needle holder
close to the blunt end 202, pierce the internal body tissue IBT to
be retracted or displaced with the needle tip 201 at the point of
entry into said tissue;
[0070] b) Pushing said needle 20 through the internal body tissue
IBT in a manner that the needle tip 201 exits through the internal
body tissue IBT;
[0071] c) With the surgical needle holder, grasping the exposed
portion of the needle 20 between the needle tip 201 and its point
of exit from the internal body tissue IBT, and threading a length
of suture line 23 through the internal body tissue IBT, for example
a length between point A and point C on the suture line 23, also
referred to as the threaded length AC (FIGS. 1A-1B). A length
between point C and point D of suture line 23 remains contained
within the internal body tissue IBT, and will also be referred to
as the bearing length CD, and a length between point D and point F
of suture line 23 is not threaded through the internal body tissue
IBT, and will also be referred to as unthreaded length DF;
[0072] d) Pulling on the two lengths AC and DF simultaneously and
sufficiently to effectuate and maintain the desired internal body
tissue IBT retraction, or to effectuate and maintain the desired
displacement of the internal body tissue IBT from its anatomical
disposition, or to effectuate and maintain the desired displaced
position or displaced orientation of a body organ through the
retraction of internal body tissue IBT that is anatomically
attached to said body organ;
[0073] e) While maintaining the pulling loads on the two lengths AC
and DF for the desired internal body tissue IBT retraction (one
length in each hand), insert a segment within length AC of suture
line 23 into slit-like channel 72 (or 82) and over the opening of
aperture 902 of one of the anchoring ports 90 disposed on sternum
retractor 1, (point B of suture line 23 is at this point situated
over aperture 902--FIG. 1C);
[0074] f) While maintaining the pulling loads on the two lengths AC
and DF for the desired internal body tissue IBT retraction, bring
the suture-locating slot 251 of anchoring plug 25 in contact with
the segment of suture line 23 at point B over aperture 902, and
insert and engage the anchoring plug 25 into said aperture 902 with
a downward force thereby securing the desired internal body tissue
IBT retraction or displacement according to (d);
[0075] g) if required, readjust the magnitude of retraction applied
to the internal body tissue IBT or readjust the magnitude of
displacement exerted on the internal body tissue IBT by first
disengaging anchoring plug 25 from aperture 902 and reengage by
repeating steps (d) to (f) above, with a different pulling force to
effectuate and maintain the desired readjustment in internal body
tissue IBT retraction or displacement;
[0076] h) if required, readjust the direction of retraction load
applied to internal body tissue IBT or readjust the direction of
displacement exerted thereon by first disengaging anchoring plug 25
from existing aperture 902 and re-engage said anchoring plug into
another anchoring port 25 forming part of the plurality of such
anchoring ports, by repeating steps (d) to (f) above.
[0077] FIG. 1C illustrates one of the ways tissue retractor 2 can
be deployed, as outlined above in broad terms. FIG. 1C illustrates
the anchoring plug 25 in the partially inserted position with the
aperture 902. Only a segment within length AC of suture line 23 is
engaged, into slit-like channel 72 and another segment of suture
line 23 in the vicinity of point B is pressed through the opening
of aperture 902 by virtue of this latter segment's engagement
within suture-locating slot 251. The suture line 23 of tissue
retractor 2 is secured in a substantially fixed relation to the
anchoring port 90 by the action of sufficiently pressing down on
and wedging the anchoring plug 25 into aperture 902, in a manner to
pinch or trap the segment of suture line 23 that is engaged between
the outer surface 252 of plug 25 and surface of aperture 902,
thereby maintaining the desired internal body tissue IBT retraction
load or displacement. The deployment of tissue retractor 2 is now
complete. It is preferable in this method of deploying tissue
retractor 2 that each of the lengths AC and DF of suture line 23 is
held by a separate hand until the tissue retractor 2 is fully
engaged with the anchoring port 90, and its deployment complete.
With the suture line 23 in tension from the retraction load the
surgeon applies to the internal body tissue IBT, and with a segment
within length AC of suture line 23 engaged in slit-like channel 72,
a V-notch 905 in fitting 901 serves advantageously to align a
segment within length AC of suture line 23 over the opening of
aperture 902 poised to receive the suture-locating slot 251 of plug
25 when said plug is inserted in aperture 902 with another
hand.
[0078] FIG. 1D illustrates an alternate method of deployment of
tissue retractor 2 in anchoring port 90. The anchoring plug 25 is
shown prior to its insertion into aperture 902. Unlike the previous
method of deployment described above in reference to FIG. 1C, both
lengths AC and DF of suture line 23 are held by the surgeon in one
hand, preferably between point A and B on one length and between
point E and F on the other length, after the internal body tissue
IBT is pierced with needle 201 and a portion of suture line 23
denoted as length CD thereof is contained within internal body
tissue IBT. The surgeon pulls on both lengths AC and DF
simultaneously with one hand to apply and maintain the desired
retraction or displacement of the internal body tissue IBT, while
inserting a segment within length AC and a segment within length DF
in slit-like channel 72. Also by this action, a segment within
length AC in the vicinity of point B and a segment within length DF
in the vicinity of point E are disposed over aperture 902, ready to
receive suture-locating slot 251 of anchoring plug 25 as said plug
is inserted in aperture 902 and engaged with anchoring port 90 by
the action of the other hand. Like in the previous method of
deployment, the suture-locating slot 251 serves to locate the
portions of suture line 23 it contacts in a substantially diametric
orientation with respect to the free end of plug 25. The suture
line 23 of tissue retractor 2 is secured in the same manner as in
the first method of deployment described above, with the exception
that two segments of suture line 23 (one in the vicinity of point B
and the other in the vicinity of point E) will be pinched or
trapped between the outer surface 252 of plug 25 and the surface of
aperture 902, thereby maintaining the desired internal body tissue
IBT retraction load or displacement.
[0079] Adjustment of the magnitude of the retraction force exerted
on the internal body tissue IBT or the magnitude of displacement of
the internal body tissue IBT from its original position in the body
is accomplished by disengaging anchoring plug 25 from the anchoring
port 90, thereby freeing the trapped segment or segments of suture
line 23, and re-inserting and re-engaging said plug 25 into said
port 90 in such a manner as to trap or fix a different segment or
segments of suture line 23. Trapping or fixing a segment of suture
line 23, within length AC, that is closer to point C (or
simultaneously fixing a segment of suture line 23 within length AC
that is closer to point C and another segment within length FD that
is closer to point D) will result in an increase in displacement of
internal body tissue IBT from its original position within body,
and usually also result in an increase in the retraction load
applied to achieve such displacement.
[0080] Adjustment of the direction of the tissue retraction force
exerted by the suture line 23 on internal body tissue IBT is
accomplished by removing anchoring plug 25 from the anchoring port
90, thereby freeing the trapped segment or segments of suture line
23, and re-inserting the said plug 25 into another anchoring port
90 situated at a different location on the sternum retractor 1 in
such a manner as to trap a different segment or simultaneously
different segments of the suture line 23. This effectively changes
the orientation of the suture line 23 with respect to the internal
body tissue IBT, and consequently the direction of the retraction
force applied to the internal body tissue IBT. Adjustment of both
the magnitude and direction of the retraction force is possible by
simultaneously moving anchoring plug 25 and suture line 23 into
another anchoring port 90 and by varying the suture length BC and
DF (first method of deployment) or BC and DE (second method of
deployment) between the internal body tissue IBT and the anchoring
port 90.
[0081] In both methods of deployment of the tissue retractor 2
illustrated in FIGS. 1C and 1D, the desired retraction or
displacement of the internal body tissue IBT is accomplished
without the need to manually tie down suture lines in the manner
previously explained. In both said methods of deployment,
adjustment of the magnitude of retraction of displacement of the
internal body tissue IBT or adjustment of the direction of
retraction load applied on the internal body tissue IBT or its
direction of displacement may be accomplished without having to
dispose of existing suture and re-piercing the internal body tissue
IBT with a newly deployed suture.
[0082] As mentioned in the description of this first embodiment,
and as illustrated in FIGS. 1A-1D, the fitting 901 preferably
assumes a substantially horizontal orientation, and the
longitudinal axis of aperture 902 is preferably substantially
vertical. Alternatively, the fitting 901 can assume an orientation
that is other than horizontal, or the longitudinal axis of aperture
902 can assume a non-vertical orientation, or even both the fitting
901 orientation and aperture 902 orientation may be varied
simultaneously, while still maintaining the principles and
obtaining the desired results of the present invention as described
above.
[0083] In this first embodiment according to the present invention,
the anchoring port 90 and the anchoring plug 25 cooperate and
together serve as an anchoring mechanism. A variety of geometries
for the anchoring port 90 and anchoring plug 25 are possible which
serve the intended purpose of trapping, wedging, clamping,
pinching, or otherwise substantially fixing a segment of the suture
line 23 relative to a substantially stable surgical platform, such
as a sternum retractor 1. FIGS. 2A to 2C illustrate a few geometric
variations for the said anchoring plug. FIG. 2A illustrates a
tapered anchoring plug 26 with a multitude of substantially
circumferential ridges 261 spaced along plug outer surface 262. Two
adjacent ridges 261 serve to trap a segment of suture line 23
therebetween, and at least one of the said ridges serves to pinch
the two endpoints of said trapped segment between the surface of
ridge 261 and the surface of aperture 902, when anchoring plug 26
is fully engaged in anchoring port 90. FIG. 2B illustrates a
tapered anchoring plug 27 comprised of a series of progressive
conical wedges 271. FIG. 2C illustrates a tapered hexagonal
anchoring plug 28. For each of these variant anchoring plug
geometries, the corresponding aperture 902 geometry must cooperate
with these said plug geometries to achieve the intended use of
substantially fixing the segment of suture line 23 engaged within
aperture 902 relative to the sternum retractor 1, thereby
maintaining the tensile retraction load in the suture line 23 and
the desired internal body tissue IBT retraction. For example, the
said aperture cooperating with hexagonal anchoring plug 28 is also
preferably substantially hexagonal in cross section tending to
improve the fit between said cooperating components. The anchoring
plugs 25,26,27 and 28 shown in the preceding figures are preferably
manufactured in a polymer or substantially rubber-like compound in
order to tend to improve their conformance and adherence to the
mating geometry of cooperating aperture 902. The said anchoring
plugs may be at least partially elastic, partially malleable, or
partially compliant in the sense that at least those portions of
the anchoring plugs which contact the cooperating aperture will
exhibit the desired characteristics of elasticity, malleability, or
compliance. With such a construction, the said anchoring plugs are
typically not well-suited for conventional steam sterilization and
are typically disposable elements. In addition to having a geometry
to suit the said anchoring plug geometry of specific variants, the
surfaces of the said aperture can be manufactured or coated with a
surface texture to further enhance friction, fit, or adherence with
the engaged said anchoring plug.
[0084] In this first embodiment the components comprising the
tissue retractor 2, for instance is the curved needle 20, the
suture line 23, and the anchoring plug 25 form an integral
assembly, which can be advantageously packaged in sterilized
packets similar to standard suture packets. This integral essembly
would be a single use disposable implement as is the case with
existing sutures. The components comprising the anchoring port 90,
which may be either integral or mechanically assembled to a
surgical platform such as a preferably reusable sternum retractor
1, would also be preferably reusable. As explained below, the
tissue retractor 2 offered in disposable form and available in
ready-to-use sterilized packets also provides the possibility for
classifying some of the variables of the tissue retractor
configuration. For instance, the tissue retractor can be offered in
a variety of classified suture line 23 lengths, a variety of
classified suture line 23 materials, a variety of classified suture
line 23 widths, a variety of tissue-piercing needle 20
configurations, to name but a few examples. This allows the surgeon
to select the most suitable sterilized packet to perform the
specific tissue retraction operation, similar to the current
classification and selection practice that is followed with
traditional surgical sutures. In another variant, the suture line
23 with integral needle 20 is offered as traditional disposable
suture, and the anchoring plug is a separate reusable component,
manufactured in metal, and endowed with compliant properties by
virtue of its mechanical design in order to aim to enhance its fit
and cooperation with the aperture geometry. In another variant, the
needle 20 can be detachable from the suture line 23 at point A,
after the tissue retractor 2 is completely deployed, in order to
remove the risk of having a sharp tip 201 exposed during the
surgical intervention.
[0085] FIGS. 3A-3C illustrate further variants of tissue retractor
2 by replacing anchoring plug 25 with anchoring plugs 29, 30 or 31
that include handle members 291, 301 and 311, respectively. Handle
members 291, 301 and 311 tend to facilitate the manipulation of
said anchoring plugs 29, 30 and 31 especially with regards to
insertion and removal of said plugs from anchoring port 90, by
either a human hand or through the use of a surgical implement.
Suture line 23 is attached to said handle members at point A,
preferably along the central longitudinal axis defining said
anchoring plugs. The said handle members are preferably configured
with circular outer profiles 293, 303 and 313, but may also be
configured with other non-circular outer profiles suitable to
facilitate manipulation of said anchoring plugs. The handle members
291, 301, 311 are also preferably manufactured integral with the
anchoring plugs 29, 30, 31. FIG. 3A illustrates a basic disc shaped
handle member 291; FIG. 3B illustrates a disc shaped handle member
301 with integral traction ridges 302 tending to reduce slippage
during manual manipulations, especially with wet surgical gloves;
FIG. 3C illustrates an annular handle member 311 permitting the
insertion of either a human finger or surgical implement through
opening 312 to tend to facilitate disengagement of plug 31 from
anchoring port 90.
[0086] The said handle members may also advantageously serve to
allow the surgeon to apply a rotation, about the longitudinal axis
of the said anchoring plug, at some point during the insertion
procedure of said anchoring plug into anchoring port 90, before the
complete deployment of the tissue retractor is accomplished. This
enables an anchoring plug with a circular cross-sectional area (in
a plane perpendicular to its longitudinal axis) except for a local
raised dimple or longitudinal bulge along its outer surface, to be
easily inserted in one discrete orientation relative to the
anchoring port 90 by virtue of the aperture 902 having a volumetric
provision to accommodate said dimple or said bulge in said discrete
orientation relative to anchoring port 90. Rotation of the handle
member can serve to compress anchoring plug across its dimple or
bulge, as anchoring plug is forced to assume a new orientation
within anchoring port 90 whereby said volumetric provision in said
aperture opening is no longer engaged by the anchoring plug dimple
or bulge. This rotation thereby tends to secure the anchoring plug
within the anchoring port, and with a segment of suture line 23
pinched between said plug and said aperture, the intended purpose
of the invention is fulfilled.
[0087] FIG. 4A illustrates a further variant of tissue retractor 2
by replacing anchoring plug 25 with anchoring plug 32. Like the
previous embodiments, anchoring plug 32 preferably forms an
integral assembly with suture line 23 which originates from its top
face 323, and curved needle 20 attached to other end of suture line
23 (not shown). Anchoring plug 32 is advantageously manufactured
with a longitudinal slot 322 preferably extending along the entire
length of said plug. The outer surface 321 of plug 32, in its free
unconstrained state prior to its insertion and engagement with
anchoring port 90, defines a cross section (transversely to plug
longitudinal axis and neglecting cross section of slot 322) that is
substantially larger than the cooperating transverse cross section
in aperture 902. The material of the plug is substantially elastic
or substantially malleable such that when said plug 32 is inserted
and engaged in aperture 902, the outside surface 321 will be
compressed and constrained into assuming a smaller cross section,
due largely to the resulting narrowing of circumferential width of
slot 322. Consequently, a segment within length AC of suture line
23 (or a segment within length AC and segments within length DF of
suture line 23) engaged within slot 322 will be clamped by the
opposing surfaces defining slot 322. The suture line 23, loaded in
tension by the retraction load it applies to the internal body
tissue IBT, will thereby be fixed relative to the completely
engaged plug 32 in port 90, and thereby tending to maintain the
desired internal body tissue IBT retraction. This configuration of
anchoring plug 32 may be advantageous in tending to reduce slippage
and tending to increase the pinching or clamping force exerted on
the suture line 23 to keep the engaged length of said suture line
fixed or secured relative to the anchoring plug 32 and anchoring
port 90. Adjustment of the magnitude of the retraction force
exerted by the suture line 23 on the internal body tissue IBT or
the magnitude of displacement of the internal body tissue IBT from
its original position in the body is accomplished by disengaging
anchoring plug 32 from port 90 and displacing through slot 322 at
least one of the engaged segments of suture length 23 to thereby
engage a different segment of suture line 23. Adjustment of the
direction of the tissue retraction force exerted by the suture line
23 on the internal body tissue IBT is accomplished by disengaging
plug 32 and re-engaging said plug into another anchoring port 90
situated at a different location on the sternum retractor 1, in
such a manner as to clamp different segments of suture line 23 in
the manner described above. The inner surfaces of longitudinal slot
322 can be substantially smooth, as illustrated in FIG. 4A, or
alternatively can be textured, rough or serrated to tend to
increase the friction force exerted on engaged suture line 23 when
it is clamped between said surfaces during engagement of plug 32
into port 90. The slot 322 is illustrated in a substantially
longitudinal configuration relative to plug 32 but may
alternatively assume a substantially helical disposition about the
longitudinal axis of said plug 32.
[0088] FIG. 4B illustrates a further variant of tissue retractor 2
by replacing anchoring plug 25 with anchoring plug 33 and, like the
previous embodiments, preferably forms an integral assembly with
suture line 23 and curved needle 20 (not shown). Plug 33 is
configured with a suture-locating slot 331 substantially transverse
to the longitudinal axis of the plug 33. Relative to
suture-locating slot 251 of the first embodiment, slot 331 tends to
improve the cooperation of plug 33 with the engaged segment or
segments of suture line 23 during insertion and removal of said
plug into anchoring port 90. During insertion of plug 33 into
anchoring port 90, the engaged segment of suture line 23 is in
contact with concave surface 332 of said slot 331. During
disengagement of plug 33 from port 90, the engaged segment of
suture line 23 is in contact with concave surface 333 of said slot
331. Unlike the first embodiment illustrated in FIGS. 1A-1D, when
plug 33 is fully engaged in port 90, the engaged segment or
segments of suture line 23 located within slot 331 are contained
within the surfaces defining aperture 902, and said engaged segment
or segments are not exposed below the fitting 901 as is the case in
this first embodiment where suture locating slot 251 is configured
on the free end of plug 25. Alternatively, slot 331 may be replaced
by a substantially transverse hole. In this variant, after the
internal body tissue IBT tissue is pierced and a length AC of
suture line 23 threaded through said internal body tissue IBT, the
curved needle 20 is then inserted through said hole along with a
length AB of suture line 23 which is also threaded through said
hole prior to insertion and engagement of anchoring plug in
anchoring port 90.
[0089] In the remaining embodiments, the portion of the internal
body tissue IBT that is pierced by needle 20 and threaded by suture
line 23 is not illustrated. However, if illustrated the internal
body tissue IBT would contain and shield length CD of suture line
23, also previously defined as the bearing length CD. Point C is
the point along the length of suture line 23, of a fully deployed
tissue retractor 2, that lies at the point of exit of said suture
line 23 from the retracted internal body tissue IBT. Point D is the
point along the length of suture line 23, of a fully deployed
tissue retractor 2, that lies at the point of entry of said suture
line 23 into the retracted internal body tissue IBT.
[0090] FIG. 5A illustrates a second embodiment according to the
present invention. The tissue retractor 12 is comprised of a
tissue-piercing member such as a curved needle 20, a wire-like
filament such as a suture line 23, an anchoring member such as
anchoring plug 34, and an anchoring port 91. Unlike the first
embodiment, the anchoring plug 34 in this second embodiment is not
rigidly attached to the suture line 23 at a fixed location along
its length, but is slidingly engaged to said suture line 23 and
thereby capable of assuming any location along the entire length AF
of suture line 23. Anchoring plug 34 is substantially
diamond-shaped with substantially planar faces 341, 342, 343, and
344 forming the suture-contacting perimeter of said diamond shape.
A suture guide passage 346 extends through anchoring plug 34, and
is of a suitable width dimension to allow insertion of suture line
34 through said passage 346. The longitudinal axis of passage 346
substantially bisects the wedge angle formed by face 341 and 344,
and also by face 342 and 343. Preferably, the assembly fit that
results between the inserted portion of suture line 23 and passage
346 is not loose, and the force required to slide the anchoring
plug 34 along at least a length of suture line 23 may be easily
overcome by the manual force applied by surgeon. Once the anchoring
plug 34 is inserted on the suture line 23, the width of the suture
line 23 at its free end 349 is preferably enlarged to prevent plug
34 from disengaging suture line 23 during subsequent manipulations
or deployment of tissue retractor 12. This may be achieved either
through the formation of a knot placed in suture line 23 in the
vicinity of its free end 349, or alternatively during the
manufacturing process of tissue retractor 12 when an end fitting,
such as a spherical end cap (not shown) of larger width dimension
than suture line 23 can be permanently mounted to the said free end
349. Cooperating with anchoring plug 34 to accomplish the desired
internal body tissue IBT retraction is anchoring port 91. FIG. 5B
schematically illustrates a substantially rigid and substantially
stable platform 11, for instance at a location on the sternum
retractor 1, onto which is disposed anchoring port 91. FIG. 5B also
schematically represents a top view of a sectioned anchoring port
91. Port 91 is configured with a narrow slit-like channel 912,
which may also be an extension of slit-like channel 72 in outward
direction from surgical window SW. In moving outwardly relative to
surgical window SW, the faces defining the width of slit-like
channel 912 diverge to form a wedge shaped aperture 914 defined by
two diverging faces 911. Surface 913 forms the bottom face of
slit-like channel 912 and the bottom face of wedge aperture 914,
thereby also serving as a location datum for lateral faces 345 of
anchoring plug 34, when said plug is engaged in said port. The
geometry of the wedge aperture 914 and the geometry of diamond
shape anchoring plug 34 substantially coincide to properly
cooperate during the deployment of the tissue retractor 12.
[0091] FIG. 5B illustrates a fully engaged tissue retractor 12
within wedge shaped aperture 914, according to a first preferred
method of deployment. As previously explained, the anchoring plug
34 may be manufactured in a material or design that makes it at
least partially malleable or partially elastic to tend to improve
its conformity to cooperating faces 911 and its compliance around
the engaged suture line that it will pinch against faces 911 In
broad terms, this preferred method deployment for this second
embodiment according to the present invention, consists of:
[0092] (a) piercing the internal body tissue IBT with needle 20 and
threading a length AC of suture line 23 through said internal body
tissue IBT;
[0093] (b) retracting pierced internal body tissue IBT by
simultaneously pulling on both lengths AC and DF of suture line
23;
[0094] (c) selecting the most convenient anchoring port 91 from the
plurality disposed around sternum retractor 1, estimating the
required location of anchoring plug 34 along suture line 23 to be
able to secure the desired internal body tissue IBT retraction by
engagement of anchoring plug 34 into the selected anchoring port
91;
[0095] (d) sliding the anchoring plug 34 along suture line 23 to
the said required location;
[0096] (e) in length DF of suture line 23 (between internal body
tissue IBT and free end 349), rotating the diamond shape anchoring
plug 34 such that point E1 on suture line 34 comes in contact with
face 342, and point E2 comes in contact with face 343;
[0097] (f) bringing length AC of suture line 23 (between internal
body tissue IBT and needle 20) in contact with anchoring plug 34
such that point B comes in contact with face 343;
[0098] (g) while holding anchoring plug 34 in the relationship
described in (f) above, simultaneously pulling on both lengths of
suture line 23, preferably between point B and C on one length and
point D and E1 on the other length, to exert the desired internal
body tissue IBT retraction;
[0099] (h) while maintaining the desired internal body tissue IBT
retraction, inserting simultaneously a portion of each length BC
and DE1 in slit-like channel 912, and also inserting anchoring plug
34, with the above said relationship to suture line, in wedge
aperture 914 (lengths E2F and AB of suture line 23 extending beyond
port 91 preferably in outwardly direction from surgical window
SW);
[0100] (i) releasing anchoring plug 34;
[0101] j) if required, readjusting the magnitude of retraction load
exerted on internal body tissue IBT by first pulling simultaneously
on lengths BC and DE1 of suture line 23, in a manner to increase
retraction load slightly thereby loosening wedging action between
plug 34 and port 91. Secondly disengaging plug 34 from port 91 and
repeating steps (b) to (h) above;
[0102] (k) if required, readjusting the direction of retraction
load applied to internal body tissue IBT or readjusting the
direction of displacement exerted on internal body tissue IBT by
performing step (j) above but only re-engaging anchor 34 into
another port 91 located along the perimeter of sternum retractor
1.
[0103] In this preferred method of deployment, the tensile load in
length BC and DE1 of suture line 23, due to the retraction exerted
on internal body tissue IBT, tends to wedge diamond faces 343 and
342 into wedge faces 911 of port 91 thereby pinching or clamping
suture line engaged between 911 and said wedge diamond faces. In
addition, this said tensile load in length BC and DE1 tends to
impart a moment on anchoring plug 34 and rotate it in a clockwise
direction as it is illustrated in FIG. 5B, within wedge aperture
914. This tends to increase the pinching action by anchoring plug
34 on engaged suture line 23, especially at corner locations 347
and 348. Suture-contacting perimeter faces 341, 342, 343, or 344
may be textured, rough or serrated to tend to increase the friction
force exerted on engaged suture line 23 when it is clamped between
some of the said perimeter faces and faces 911 of wedge aperture
914, which may also be textured.
[0104] A second alternate method of deployment (not illustrated),
in broad terms, consists of eliminating step (e), that is,
eliminating the rotation of diamond plug 34 so that E1 is in
contact with 342 and E2 is in contact with 343. In this second
method, point B is in contact with perimeter face 341 but length DF
passes directly through passage 346 without being wrapped around
any of the perimeter faces 341, 342, 343, or 344. In this method of
deployment, it is preferable to have an anchoring plug 34
configured with a longitudinal slit through one of the side faces
345, preferably in communication with the entire length of passage
346. This configuration attempts to augment the clamping force on
the length of suture line 23 engaged in passage 346 by virtue of
the wedging action on faces 343 and 342 transmitting a closing
force across this said longitudinal slit. Therefore, in this method
of deployment length AC is pinched or clamped at location B between
face 341 and wedge face 911 of aperture 914 and the other length DF
is clamped over the engaged length contained in passage 346, that
falls between points E1 and E2.
[0105] In this second embodiment according to the present
invention, the anchoring port 91 and the anchoring plug 34
cooperate and together serve as an anchoring mechanism. Other
geometric variations of the anchoring plug 34 and the cooperating
anchoring port 91 are possible without departing from the spirit of
this second embodiment. FIGS. 5C and 5D illustrate two such
variations; a rectangular-shaped plug 35 is shown in FIG. 5C while
a triangular wedge-shaped plug 36 is shown in FIG. 5D. Other
geometric variations for the anchoring plug may include an
elliptical-shaped anchoring plug. All these variants may be
deployed in at least one of the methods of deployment described
above.
[0106] FIG. 6A illustrates the third embodiment according to the
present invention. Internal body tissue IBT retraction will be
effectuated with a traditional suture 13, comprised of a curved
suture needle 20 and a suture line 23, that becomes engaged with
anchoring mechanism 92 disposed on sternum retractor 1, in a
plurality of locations similar to the disposition of anchoring
ports 90 of the first embodiment. FIG. 6A illustrates only the most
remote portion relative to rack bar 5 of retractor spreader arm 3,
with one anchoring mechanism 92 disposed laterally outward on said
arm 3.
[0107] Anchoring mechanism 92 is comprised of the following
components: a housing 922, a pinch roller 934, a traction roller
93, a retention pin 928, and a shoulder bolt 932. The housing 922
may be either an integral extension of retractor arm 3 (or 4) or
may be mechanically fastened to said retractor arm to form a rigid
assembly during at least the duration of the surgical intervention
requiring tissue retraction.
[0108] Housing 922, serving to retain or to partially house the
cooperating components of anchoring mechanism 92, is defined by: a
base platform 921 which disposes threaded hole 927 for engagement
of shoulder bolt 932 and hole 926 for engagement of retention pin
928 (FIG. 6B); a wall member 925 (FIG. 6B) which is configured with
traction surface 923 over at least a portion of its entire surface;
and a top plate 924. A substantially tubular pinch roller 934 is
mechanically assembled to the base platform 921 by shoulder bolt
932, whose thread 933 engages with threaded hole 927 (FIG. 6B),
said shoulder bolt rigidly engaged to base platform 921 after
assembly. Axial movement of pinch roller 934 is limited in one
direction by the shoulder 935 and in the other direction by
platform 921. Lateral movement of pinch roller 934 (i.e.
perpendicular to its centerline) is limited by the clearance
between the outer diameter of shank 936 and inner diameter 937 of
pinch roller 934. This said clearance is preferably minimized but
sufficient to allow pinch roller 934 to rotate freely about its
centerline relative to shoulder bolt 932. Cylindrical traction
roller 93, with traction ridges 931 configured on its
circumferential surface, is subsequently inserted into the slot
created by top plate 924 and base platform 921. A cylindrical
retention pin 928 is subsequently inserted into hole 926 (FIG. 6B),
and preferably permanently fixed in said hole, either by a staked
mechanical press fit, brazing, welding, or riveting for instance,
in order to permanently trap traction roller 93 within anchoring
mechanism 92. In the same manner, threaded shoulder pin 932 may be
replaced by a stepped shoulder pin that is also permanently fixed
to housing 922 after having been inserted through pinch roller 934,
in order to permanently trap pinch roller 934 to housing 922. This
open configuration of anchoring mechanism 92 as illustrated in FIG.
6A tends to facilitate sterilization and cleaning of this surgical
apparatus if the anchoring mechanism is manufactured with reusable
materials and components.
[0109] Within the anchoring mechanism 92 mechanical assembly,
traction roller 93 is capable of limited lateral translation
(perpendicular to its centerline) in a plane substantially parallel
to base platform 921. Lateral translation of the traction roller 93
is limited by the pinch roller 934, the retention pin 928, and
traction surface 923. Within these limits the traction roller 93 is
free to rotate about its centerline, unless it is engaged with
suture line 23 and anchoring mechanism 92 assumes its fully
deployed configuration. Axial translation of traction roller 93
(along its centerline) is limited by the base platform 921 and top
plate 924 Top plate 924 extends sufficiently over the faces of
traction roller 93 to prevent it from exiting the fully assembled
anchoring mechanism 92, while still allowing the insertion of
retention pin 928 and shoulder bolt 932 into base platform 921. The
location of pinch roller 934 on base platform 921., relative to
slit-like channel 72, is such that a suture line 23 inserted in
said channel 72 and pulled taut laterally outward through the
anchoring mechanism 92 and parallel to said channel 72 would
contact pinch roller 93 in a substantially tangent orientation.
Substantially planar base platform 921 is preferably parallel to
the top surface of arcuate rail 71, and preferably offset to a
depth at least below the maximum depth of slit-like channel 72, so
that a suture line 23 engaged in anchoring mechanism 92 is capable
of assuming the deepest position within slit-like channel 72 to
tend to minimize its obstruction in arcuate passage 71.
[0110] In broad terms, the method of deployment for this third
embodiment according to the present invention, consists of:
[0111] (a) piercing the internal body tissue IBT with needle 20 and
threading a length AC of suture line 23 through said internal body
tissue IBT;
[0112] (b) simultaneously inserting both lengths AC and DF of
suture line 23 firstly in slit-like channel 72 and secondly in
between pinch roller 934 and traction roller 93;
[0113] (c) grasping both lengths AC and DF of suture line 23, in
the vicinity of point A and point F, and retracting pierced
internal body tissue IBT by pulling simultaneously both said
lengths longitudinally outward through slit-like channel 72 while
all the time maintaining suture-line lengths in contact with pinch
roller 934 by laterally loading said suture lines against said
pinch roller during the said pulling action;
[0114] (d) once the desired internal body tissue IBT retraction or
internal body tissue IBT displacement is obtained, displace the
grasped suture lines 23 laterally away from pinch roller 934
towards traction roller 93, such that at least a segment of suture
line 23 between point A and point B and at least a segment of
suture line 23 between point E and point F engages and exerts a
force towards the center of traction roller 93, thereby bringing
traction surface 931 into contact with traction surface 923 by
virtue of the lateral translation of traction roller 93;
[0115] (e) while maintaining both lengths of suture line 23
laterally forced against traction roller 93, gradually and slightly
reduce the retraction force on the grasped lengths of suture line
23, causing both said lengths to be slightly retrieved
longitudinally inward through slit-like channel 72 and entraining
traction roller 93 to roll on traction surface 923 towards pinch
roller 934;
[0116] (f) simultaneously releasing grasped lengths AC and DF of
suture line 23 when traction roller 93 is only separated from pinch
roller 934 by the width of suture line 23 trapped between said
rollers at point B and point E of suture line 23.
[0117] During step (c) of the method of deployment described above,
the lateral loading of suture lines 23 against pinch roller 934
generates a force radially inward towards the centerline of pinch
roller 934, which entrains a rotation of pinch roller 934 about its
centerline if the friction between contacting suture line 23 and
the outer diameter of pinch roller 934 is sufficient to overcome
the friction between pinch roller 934 and shoulder bolt 932.
[0118] During step (d) of the method of deployment described above,
the resultant friction force between suture line 23 and traction
ridges 931 when suture lines are laterally forced against traction
roller 93, entrains said traction roller to roll towards pinch
roller 934, by virtue of the engagement or substantial meshing
between ridges 931 and traction surface 923. Once the grasped
lengths AC and DF of suture line 23 are released, with suture line
pinched between traction roller 93 and pinch roller 934, the
friction between traction roller surface 931 and suture line 23,
along with the tensile load applied on suture lines 23 from the
resistance of the internal body tissue IBT to imposed retraction,
will try to entrain traction roller 93 to roll even closer to pinch
roller 934 by virtue of its continued engagement with traction
surface 923, and thereby tend to increase the pinching load on
suture line 23 between traction roller 93 and pinch roller 934.
[0119] Disengagement is accomplished by grasping the lengths AC and
DF of suture line 23 in the vicinity of point A and point F, and
simultaneously pulling on said lengths to increase the retraction
load on the internal body tissue IBT beyond the load currently
delivered through the traditional suture 13 being engaged in the
fully deployed anchoring mechanism 92. This action relieves the
internal body tissue IBT retraction force from the surgical
apparatus back to the surgeon's hand, and entrains traction roller
to roll away from pinch roller thereby releasing the pinching or
wedging effect between 931 and 934 responsible for securing or
fixing suture line relative to the anchoring mechanism.
Readjustment of the magnitude of internal body tissue IBT
retraction or internal body tissue IBT displacement may at this
point be accomplished by repeating steps (c) to (f) above.
Readjustment for the direction of the applied internal body tissue
IBT retraction load or for the direction of exerted displacement on
the internal body tissue IBT may be accomplished by disengaging the
suture line 23 in manner described above, and repeating steps (c)
to (f) above but engaging anchoring mechanism 92 located in another
position on sternum retractor 1.
[0120] To facilitate the insertion of suture line 23 between the
pinch roller 934 and the traction roller 93, the pinch roller 934
is configured with a dome shaped shoulder 935 and the traction
roller 93 is configured with a beveled edge 938. Alternatively, the
height of pinch roller 934 or shoulder bolt 932 may extend above
the plane of top plate 924 to facilitate insertion of suture line
23 between said pinch and traction rollers. In both cases, height
of pinch roller 934 is preferably at least equal to the height of
traction roller 93.
[0121] The traction ridges 931 on the traction roller 93 are
preferably substantially V-shaped longitudinal ridges, and the
traction surface 923 on wall 925 is preferably configured with
longitudinal substantially V-shaped grooves extending from the base
platform 921 to the top plate 924 of housing 922. A variety of
other cooperating surface textures or cooperating surface profiles
configured on the cylindrical surface of traction roller 93 and the
textured portion of wall 925, may also be used to provide a
substantial meshing between said components or substantially slip
free rolling of traction roller 93 on traction surface 923 when
said roller is loaded against said traction surface during the
deployment of tissue retractor 13, in manner described above.
[0122] FIGS. 7A-7B illustrate a fourth embodiment according to the
present invention. Internal body tissue IBT retraction will be
effectuated with a traditional suture 13, comprised of a curved
suture needle 20 and a suture line 23, that becomes engaged with
anchoring mechanism 94 disposed on sternum retractor 1, in a
plurality of locations similar to the disposition of anchoring
ports 90 of the first embodiment. FIG. 7A illustrates only the most
remote portion relative to rack bar 5 of retractor spreader arm 3,
with one anchoring mechanism 94 disposed laterally outward on said
arm 3.
[0123] Anchoring mechanism 94 is comprised of a fitting 943, and
two pawl-shaped levers: an anvil-like pawl 941 and a wedge-like
pawl 942. Fitting 943 may be either an integral extension of
retractor arm 3 (or 4) or may be mechanically fastened to said
retractor arm to form a rigid assembly during at least the duration
of the surgical intervention requiring tissue retraction. Fitting
943 is preferably disposed below the depth of slit-like channel 72.
Anvil-like pawl 941 and wedge-like pawl 942 are preferably
rotatingly engaged with fitting 943 by pivot pins 944 and 947,
respectively, which are inserted through cylindrical bores in said
pawls (not shown). Pivot pins 944 and 947 are rigidly mounted to
fitting 943 through a variety of ways, such as: a threaded
interface, by riveting, by brazing, or other like ways, in order to
keep the components comprising the anchoring mechanism 94 as an
integral mechanical assembly. The centerlines of the pivot pins 944
and 947 are parallel to each other. Anvil-like pawl 941 is
configured with a jaw 945 which comprises a planar face portion,
and wedge-like pawl 942 is configured with a jaw 946 which
comprises a sharp wedge, said jaws cooperating together and capable
of providing a concentrated clamping load to a suture line 23 which
becomes engaged between said jaws, as illustrated in FIG. 7B. Also
disposed between pivot pin 944 and cylindrical bore of anvil-like
pawl 941 is a torsion spring (not shown), engaging between pawl 941
and pivot pin 944, or alternatively between pawl 941 and fitting
943. Similarly, disposed between pivot pin 947 and cylindrical bore
of wedge-like pawl 942 is another torsion spring, engaging between
pawl 942 and pivot pin 947, or alternatively between pawl 942 and
fitting 943. The said torsion springs serve to rotate pawls 941 and
942, in opposing directions, until their respective jaws 945 and
946 come and remain in contact. The angular rotation of at least
one of the pawls 941 or 942, about its respective pivot pin 944 or
947, preferably anvil-like pawl 941, is contained within a range of
angular positions thereby ensuring that the sharp wedge portion of
jaw 946 will only contact the flat face portion of cooperating jaw
945 (when the suture is not engaged) by the action of the said
torsion springs. The angular rotation of at least one of the pawls
941 or 942 may be contained within the desired range of angular
positions by limit stops or limit pins (not shown), for example,
disposed on the top face of fitting 943 and capable of contacting
at least a portion of the affected pawl at the limit position of
the said range of angular positions. Alternatively, an external
circumferential notch on pivot pin 944 or 947, that is contacted by
a narrower protrusion on pawl 941 or 942 respectively that extends
into the cylindrical bore of said pawl 941 or 942, may serve to
limit the desired angular range of position for the affected
pawl.
[0124] By virtue of said torsion springs, jaws 945 and 946 are
capable of applying a spring-induced clamping force to a suture
line 23 which becomes inserted between said jaws. The magnitude of
this spring-induced clamping force may be increased by increasing
the spring stiffness of said torsion springs. The topmost portion
of jaws 945 and 946 may be chamfered or profiled (not shown) to
facilitate insertion of suture line 23 between spring loaded pawls
941 and 942.
[0125] In broad terms, the method of deployment for this fourth
embodiment according to the present invention, consists of:
[0126] (a) piercing the internal body tissue IBT with needle 20 and
threading a length AC of suture line 23 through said internal body
tissue IBT;
[0127] (b) simultaneously inserting both lengths AC and DF of
suture line 23 firstly in slit-like channel 72 and secondly in
between jaw 945 of anvil-like pawl 941 and jaw 956 of wedge-like
pawl 942;
[0128] (c) grasping both lengths AC and DF of suture line 23, in
the vicinity of point A and point F, and retracting pierced
internal body tissue IBT by pulling simultaneously both said
lengths longitudinally outward through slit-like channel 72 and
through jaws 945 and 946, sufficiently to obtain the desired
internal body tissue IBT retraction or displacement;
[0129] (d) simultaneously releasing both lengths AC and DF of
suture line 23, jaws 945 and 946 being in contact with the suture
line 23 at point B and point E of said suture line;
[0130] (e) if required, readjusting to increase the magnitude of
internal body tissue IBT retraction or displacement, by
simultaneously grasping suture line 23 between lengths AB and EF,
and pulling simultaneously both said lengths in manner described in
step (c) above;
[0131] (f) if required, readjusting to decrease the magnitude of
internal body tissue IBT retraction or displacement, by: (i)
simultaneously grasping suture line 23 between lengths AB and EF,
and pulling simultaneously both said lengths upward away from
fitting 943, in a pulling direction substantially parallel to
centerline of pivot pins 944 and 947, to disengage suture line 23
from contact with jaws 945 and 946 of pawls 941 and 942,
respectively, (ii) relieving internal body tissue IBT retraction
load by applying no pulling force on said grasped suture line 23,
(iii) re-engaging suture line 23 with jaws 945 and 946 to secure
desired internal body tissue IBT retraction or displacement by
repeating steps (c) and (d) described above;
[0132] (g) if required, readjusting the direction of retraction
load applied to internal body tissue IBT or readjusting the
direction of displacement exerted on internal body tissue IBT by
disengaging suture line 23 from existing anchoring mechanism 94 and
re-engaging suture line 23 in another anchoring mechanism 94
disposed in an alternate location on sternum retractor 1, by
repeating steps (c) to (f) described above.
[0133] Alternatively, steps (b) and (c) of the method of deployment
described above may be reversed by first pulling simultaneously and
sufficiently both lengths AC and DF longitudinally outward from
surgical window SW to obtain the desired internal body tissue IBT
retraction or displacement, and subsequently inserting
simultaneously both said lengths of suture line 23 firstly in
slit-like channel 72 and secondly in between jaws 945 and jaw 946
of anchoring mechanism 94.
[0134] During step (b) of the first method of deployment described
above, a spring-induced clamping force is applied to the portions
of suture line 23 inserted between jaws 945 and 946, by virtue of
the torsion spring acting between pawl 941 and pivot pin 944 and
the torsion spring acting between pawl 942 and pivot pin 947. There
is no tension in suture line 23 since the internal body tissue IBT
is not yet retracted. In the alternate method of deployment, only
the spring-induced clamping force acts on the portions of suture
line 23 inserted between jaws 945 and 946 as long as the tension in
lengths AC and DF of suture line 23 resulting from the imposed
retraction on internal body tissue IBT, or from the displacement
exerted on internal body tissue IBT, is reacted by the surgeon's
hand and not the anchoring mechanism 94.
[0135] During step (d) of the first method of deployment described
above, the resulting tension in lengths AC and DF of suture line 23
from the imposed retraction on internal body tissue IBT, or from
the displacement exerted on the internal body tissue IBT, is
reacted by anchoring mechanism 94. When tension is applied to the
suture line 23 simultaneously at point C and point D by the
retracted internal body tissue IBT, the friction force between the
suture line 23 (at points B and E) and each of jaws 945 and 946
will cause the pawls 941 and 942 to rotate in opposition, beyond
the point of rotation of said pawls when only the action of the
torsion springs places said jaws of said pawls in contact with the
portion of inserted suture line 23. Consequently, the normal force
on the suture line 23 at point B and point E will be increased
beyond the spring-induced clamping force. The distance between the
axis of pivot pin 947 and jaw 946 is only slightly larger than half
the distance between the axis of pivot pin 944 and the axis of
pivot pin 947, and similarly the distance between the axis of pivot
pin 944 and jaw 945 is only slightly larger than half the distance
between the axis of pivot pin 944 and the axis of pivot pin 947
such that the increase in normal force on point B and point E of
suture line 23 caused by tension applied to the said suture line
simultaneously at point C and point D will always result in a
clamping friction force which is greater than the tension applied
to the suture line 23, where the said clamping friction force is
equivalent to the normal force on the suture line 23 at point B and
point E multiplied by the coefficient of friction between each of
the said jaws and the suture line 23 at point B and point E. With
the said clamping friction force greater than the tension on the
suture line 23, the suture line 23 is fully engaged in anchoring
mechanism 94, and the suture line 23 should not slip through the
jaws 945 and 946 of pawls 941 and 942 thereby securing the desired
internal body tissue IBT retraction or internal body tissue IBT
displacement.
[0136] The disengagement of suture line 23 according to step (f) in
above description of the method of deployment may be facilitated by
applying a compression force between extension 948 and extension
949 of pawls 941 and 942, respectively. This compression force
causes pawls 941 and 942 to rotate in opposition thereby releasing
portion of suture line 23 inserted or engaged between their
respective jaws 945 and 946.
[0137] In this fourth embodiment as illustrated in FIGS. 7A-7B, the
line of contact that results between jaw 945 which comprises a
planar face portion and jaw 946 which comprises a sharp wedge
portion, when said jaws come into contact by the rotation of pawls
941 and 942 about their respective pivot pin 944 and 947, is
preferably parallel to the centerline of said pivot pins. As
illustrated, the line of contact is preferably configured over the
entire height of jaws 945 and 946, but may also be reduced provided
at least a portion remains available for engagement of suture line
23 between said jaws.
[0138] Other variants for the line of contact are also possible
without departing from the spirit of this embodiment of the present
invention. For example, a grooved recess may be configured across
the planar face portion of jaw 945 (said grooved recess
substantially perpendicular to the centerline of pivot pin 944)
serving to locate a portion of suture line 23 therein. The
cooperating sharp wedge portion of jaw 946 will be configured with
a protruding wedge profile that conforms to grooved recess profile,
such that the distance between the axis of pivot pin 947 and
protruding wedge profile of jaw 946 is only slightly larger than
half the distance between the axis of pivot pin 944 and the axis of
pivot pin 947, and similarly the distance between the axis of pivot
pin 944 and grooved recess of jaw 945 is only slightly larger than
half the distance between the axis of pivot pin 944 and the axis of
pivot pin 947.
[0139] Alternatively, without departing from the spirit of this
fourth embodiment, those skilled in this act will appreciate that
pawls 941 and 942 may provide opposed cam-like surfaces which serve
as engaging jaws for the suture line. Alternatively, without
departing from the spirit of this fourth embodiment, one of the
pawls 941 or 942, preferably anvil-like pawl 941 may be rigidly
fixed relative to the fitting 943 and thereby act as a rigid
engagement surface for cooperation with wedge-like pawl 942 which
is rotatingly engaged to fitting 943 as previously described.
[0140] FIGS. 7A-7B illustrate a reusable anchoring mechanism 94,
integral with sternum retractor 1. Alternatively, a disposable
anchoring mechanism 94 assembly may be designed and mechanically
attached to a reusable sternum retractor 1 and replaced after every
surgical intervention. Alternatively, if a disposable sternum
retractor 1 is designed, the members comprising anchoring mechanism
94 may also be disposable and fabricated in single-use plastic or
polymeric materials, for instance.
[0141] An alternate design and configuration for incorporating
anchoring mechanism 94 with sternum retractor 1 consists of
embedding said anchoring mechanism within arcuate arm 3 (or 4)
below the surfaces defining arcuate passage 71, and deepening
slit-like channel 72 accordingly. As a result, the positioning and
articulation mechanism previously described may be inserted in
arcuate passage 71, positioned along arcuate passage 71, and
engaged with arcuate rail 70 even in a position over the location
of embedded anchoring mechanism 94, without any resulting
obstruction to said positioning and articulation mechanism from a
suture line secured relative to anchoring mechanism 94.
[0142] FIGS. 5A-8B illustrate a fifth embodiment according to the
present invention, one that allows the possibility of adjusting the
magnitude of the clamping load on suture line 23. Internal body
tissue IBT retraction will be effectuated with a traditional suture
13, comprised of a curved suture needle 20 and a suture line 23,
that becomes engaged with anchoring mechanism 95 disposed on
sternum retractor 1, in a plurality of locations similar to the
disposition of anchoring ports 90 of the first embodiment. FIG. 8A
illustrates only the most remote portion relative to rack bar 5 of
retractor spreader arm 3, with one anchoring mechanism 95 disposed
laterally outward on said arm 3.
[0143] Anchoring mechanism 95 is comprised of a fitting 951, a
profiled washer 953, a helical spring 954, and a screw 952. Fitting
951 may be either an integral extension of retractor arm 3 (or 4)
or may be mechanically fastened to said retractor arm to form a
rigid assembly during at least the duration of the surgical
intervention requiring tissue retraction. Fitting 951 is preferably
disposed below the depth of slit-like channel 72. Screw 952 is
comprised of a knob 958, a shoulder 957, and a threaded shaft 962.
Helical spring 954 is first inserted over threaded shaft 962,
placed in contact with the shoulder 957 of screw 952, said shoulder
having a diameter greater than diameter of helical spring 954, and
preferably a groove on face of said shoulder to house first winding
of said helical spring. Profiled washer 953 is next inserted over
threaded shaft 962. Screw 952 is then engaged with fitting 951, by
virtue of threaded shaft 962 inserted into fitting threaded hole
(not shown), in order to configure the mechanical assembly of
components defining the anchoring mechanism 95. The fitting
threaded hole is preferably a through hole, such that screw 952 may
be threaded sufficiently into threaded fitting hole to extend below
fitting 951. The exposed portion of threaded shaft 962 may, at this
point, be: (i) mechanically flared outwards, or (ii) engaged with a
transverse retention pin fitted through a hole in said threaded
shaft, or (iii) engaged with a circular clip fitted into an annular
groove in said threaded shaft, or (iv) engaged with a nut threaded
member threaded on extreme-most portion of said threaded shaft, or
(v) be engaged with other similar mechanical member preventing said
threaded shaft from being withdraw from said fitting threaded hole
without first disengaging mechanical member. This prevents
inadvertent disassembly of the anchoring mechanism 95 during the
surgical intervention, that may result by sufficiently unthreading
and disengaging threaded shaft 962 from fitting threaded hole.
Profiled-washer 953 is designed with both its outer perimeter 955
and inner perimeter 956 bent significantly away from bottom face
960 of profiled washer 953 to create firstly, a socket 964 on the
top face of profiled washer 953 to locate helical spring 954 and
secondly, a beveled outside edge between outer perimeter 955 and
bottom face 960 of said profiled washer serving as a guide to
facilitate the insertion of suture line 23 between said bottom face
960 and top face 959 of fitting 951.
[0144] When anchoring mechanism 95 is mechanically assembled, the
helical spring 954 is axially trapped between shoulder 957 of screw
952 and socket 964 of profiled washer 953, but also free to rotate
about its centerline. Helical spring 954 is also free to rotate
relative to screw 952 and free to rotate relative to washer 953.
Turning knob 958 of screw 952 such that it decreases the distance
between shoulder 957 and fitting face 959 will increase the
mechanical force that helical spring 954 applies on profiled washer
953. Conversely, if knob 958 is unscrewed sufficiently, the
increase in distance between shoulder 957 and fitting face 959 will
unload the helical spring 954 entirely, and rendering the insertion
of the portion of suture line 23 between face 960 of profiled
washer 953 and face 959 of fitting 951. To increase the clamping
load on the portion of suture line 23 between said faces 959 and
960, knob 958 is turned until the load applied by the helical
spring 954 on profiled washer 953 is sufficiently great to prevent
suture line 23 from slipping out between said faces 959 and 960
given a specific internal body tissue IBT retraction load.
[0145] In broad terms, the method of deployment for this fifth
embodiment according to the present invention, consists of:
[0146] (a) piercing the internal body tissue IBT with needle 20 and
threading a length AC of suture line 23 through said internal body
tissue IBT;
[0147] (b) simultaneously inserting both lengths AC and DF of
suture line 23 firstly in slit-like channel 72 and secondly in
between bottom face 960 of profiled washer 953 and face 959 of
fitting 951;
[0148] (c) grasping both lengths AC and DF of suture line 23, in
the vicinity of point A and point F thereof, and retracting pierced
internal body tissue IBT by pulling simultaneously both said
lengths longitudinally outward through slit-like channel 72 and
through in between face 960 and face 959, sufficiently to obtain
the desired internal body tissue IBT retraction or
displacement;
[0149] (d) screwing knob 958 sufficiently such that the clamping
load on profiled washer 953, and consequently on the suture line 23
at point B and point E, is sufficient to react the required
retraction load for desired internal body tissue IBT retraction or
displacement;
[0150] (e) simultaneously releasing both lengths AC and DF of
suture line 23, profiled washer 953 being in contact with the
suture line 23 at point B and point E of said suture line;
[0151] (f) if required, readjusting the magnitude of internal body
tissue IBT retraction or displacement, by simultaneously grasping
suture line 23 between lengths AB and EF, unscrewing knob 958 and
pulling simultaneously both said lengths in manner described in
step (c) above;
[0152] (g) if required, readjusting the direction of retraction
load applied to the internal body tissue IBT or readjusting the
direction of displacement exerted on the internal body tissue IBT
by disengaging suture line 23 from existing anchoring mechanism 95,
and re-engaging suture line 23 in another anchoring mechanism 95
disposed in an alternate location on sternum retractor 1, by
repeating steps (c) to (e) described above.
[0153] This fifth embodiment offers advantages in that the clamping
load on traditional suture 13 may be tailored to a specific
surgical intervention, or to the specific internal body tissue that
will be retracted or displaced. For example, if the risk of
applying an exceedingly high load during a surgical intervention on
the retracted internal body tissue IBT will result in unwanted
tearing of body tissue, the maximum clamping load that can be
exerted on the suture line 23 may be set to a prescribed value by
turning knob 958 a specific amount that will preload helical spring
954 such that surgical loads applied to the internal body tissue
IBT higher than this prescribed value will result in the suture
line 23 being released from anchoring mechanism 95, rather than
resulting in unwanted tearing of body tissue or unwanted tissue
trauma. In this manner, the components of the anchoring mechanism
95 cooperate to provide a failsafe feature.
[0154] FIG. 8B illustrates suture line 23 inserted in anchoring
mechanism 95, during step (b) of the method of deployment described
above, with screw 952 sufficiently unscrewed to relieve profiled
washer 953 and portion of suture line 23 inserted in anchoring
mechanism 95 free of any clamping load from helical spring 954.
[0155] If it is desired to ensure that profiled washer 953 will not
rotate relative to screw 952 when turning knob 958, a guide pin
(not shown) may be inserted into top face 959 of fitting 951, said
pin standing sufficiently proud above said surface 959 that it is
capable of engaging a hole, eccentrically located relative to the
centerline of profiled washer 953, thereby fixing the angular
rotational position of profiled washer 953 relative to fitting
951.
[0156] Alternatively, this fifth embodiment may be modified to
provide clamping of a portion of suture line 23 without the
failsafe feature described above, and without a controllable
application of clamping load on said portion of suture line. Spring
954 and profiled washer 953 may be eliminated and the portion of
suture line 23 clamped between shoulder 957 of screw 952 and face
959 of fitting 951. As a result, only two substantially discrete
clamping load settings are obtained, either zero clamping or
fully-engaged-thread clamping load for a specific thread 962 size.
Alternatively, other variants to this fifth embodiment are possible
such as those which may incorporate a Belleville washer, wave
spring, helical spring washer, or other like washers, known in the
field of mechanical design and available in a variety of sizes and
shapes.
[0157] FIGS. 9A-9B illustrate a sixth embodiment according to the
present invention, one that tends to be energized by the very
tension it is intended to react in suture line of tissue retractor.
Internal body tissue IBT retraction will be effectuated with a
traditional suture 13, comprised of a curved suture needle 20 and a
suture line 23, that becomes engaged with anchoring mechanism 97
disposed on sternum retractor 1, in a plurality of locations
similar to the disposition of anchoring ports 90 of the first
embodiment. FIG. 9A illustrates only the most remote portion
relative to rack bar 5 of retractor spreader arm 3, with one
anchoring mechanism 97 disposed laterally outward on said arm
3.
[0158] Anchoring mechanism 97 is comprised of a fitting 971, a
carriage 972, a swing plate 977, a pinch arm 974, and an energizing
arm 975. Fitting 971 may be either an integral extension of
retractor arm 3 (or 4) or may be mechanically fastened to said
retractor arm to form a rigid assembly during at least the duration
of the surgical intervention requiring tissue retraction.
[0159] Swing plate 977 is rotatingly engaged with carriage 972 by
pivot pin 973, which is firstly slidingly inserted through a
cylindrical bore (not shown) in carriage 972, and secondly rigidly
engaged into an opening on swing plate 977, by a variety of ways
similar to the rigid engagement of pins in previously described
embodiments. Swing plate 977 is free to rotate about the centerline
axis of pivot pin 973, which axially retains said swing plate 977
relative to carriage 972. Swing plate 977 is comprised of two
substantially cylindrical cantilevered shafts, a pinch arm 974 and
an energizing arm 975, both of which are preferably rigidly
attached to swing plate 977, and both of which have their
longitudinal axes preferably perpendicular to plate 977. Pinch arm
974 is positioned on plate 977 such that substantially cylindrical
surface 979 of pinch arm 974 opposes carriage surface 980 when said
swing plate 977 rotates to clamp across a portion of suture line 23
inserted and engaged between said surfaces 979 and 980. The axis of
pivot pin 973, longitudinal axis of pinch arm 974, the longitudinal
axis of energizing arm 975, and the longitudinal axis of carriage
surface 980 are all parallel to each other.
[0160] In broad terms, the method of deployment for this sixth
embodiment according to the present invention, consists of:
[0161] (a) piercing the internal body tissue IBT with needle 20 and
threading a length AC of suture line 23 through said internal body
tissue IBT;
[0162] (b) simultaneously inserting both lengths AC and DF of
suture line 23 between energizing arm 975 and pinch arm 974 by
winding said both lengths firstly around the energizing arm 975 and
secondly around the pinch arm 974 as illustrated in FIG. 7A;
[0163] (c) grasping both lengths AC and DF of suture line 23, in
the vicinity of point A and point F, and retracting pierced
internal body tissue IBT by pulling simultaneously both said
lengths longitudinally outward through anchoring mechanism 97 (in
direction perpendicular to axis of pivot pin 973), sufficiently to
obtain the desired internal body tissue IBT retraction or
displacement;
[0164] (d) simultaneously releasing both lengths AC and DF of
suture line 23, resulting in point B and point E of said suture
line being engaged between cylindrical surface 979 and carriage
surface 980;
[0165] (e) if required, readjusting the magnitude of internal body
tissue IBT retraction or displacement, by simultaneously grasping
both lengths AB and EF of suture line 23, and pulling
simultaneously both said lengths in manner described in step (d)
above;
[0166] (f) if required, readjusting the direction of retraction
load applied to internal body tissue IBT or readjusting the
direction of displacement exerted on the internal body tissue IBT
by disengaging suture line 23 from existing anchoring mechanism 97,
and re-engaging suture line 23 in another anchoring mechanism 97
disposed in an alternate location on sternum retractor 1, by
repeating steps (c) to (e) described above.
[0167] When a tension load is applied to suture line 23 at point C
and D, and when said suture line is in tension and deflected around
energizing arm 975 as illustrated in FIG. 7A, the normal force
between cylindrical surface 979 and carriage surface 980 is
amplified relative to both the tension acting on suture line 23 and
the closing force acting on energizing arm 975, by virtue of the
leverage effect imparted by swing plate 977. The distance between
longitudinal axis of pinch arm 974 to the centerline of pivot pin
973 is inferior to the distance between longitudinal axis of
energizing arm 975 to the centerline of pivot pin 973, preferably
by 30 to 70 percent, such that the resultant clamping force
generated by the amplified normal force between cylindrical surface
979, carriage surface 980, and the portion of suture line 23
engaged therebetween will always be greater than the tension
applied in suture line 23 at point C and D. The said resultant
clamping force being greater than the said tension results in the
suture line 23 being secured relative to anchoring mechanism
97.
[0168] Tension applied to suture line 23 at point A and point F
opposes and reduces the resultant clamping force on suture line 23
at point B and point E engaged between cylindrical surface 979 and
carriage surface 980. Tension applied to suture line 23 at point A
and point F can be applied to such an extent as to completely
overcome the said resultant clamping force, thus allowing suture
line 23 to be pulled, as desired, to slide through the cooperating
surfaces 979 and 980 of anchoring mechanism 97 in the direction of
application of said tension. Guide knob 987 on pinch arm 974 and
guide knob 988 on energizing arm 975 serve to discourage
disengagement of suture line 23 from said arms 974 and 975 should
there be any significant misalignment between either of length AC
or length DF of suture line 23 and a plane perpendicular to the
longitudinal axes of arms 974 and 975.
[0169] FIGS. 9A-9B illustrates this sixth embodiment according to
the present invention with the engaged suture line 23 extending
above both the arcuate rail 70 and arcuate passage 71.
Alternatively, similar to the previous embodiments, the fitting 971
and carriage 972 may be configured at a lower depth on sternum
retractor 1, and slit-like passages 72 included in arcuate arm 3
such that the engaged suture line 23 will rest at the maximum depth
of slit-like channel 72 thereby providing an unobstructed access to
arcuate passage 71 for the positioning and articulation mechanism
described above.
[0170] The embodiments of the present invention may be used in
beating heart coronary artery bypass graft (CABG) surgery to
position and orient the beating heart within the retracted chest
cavity of the patient by applying a tissue retraction load to the
pericardium tissue. The pericardium tissue is typically incised to
expose at least a portion of the heart surface where the bypass
graft will be performed, but remains anatomically attached to the
beating heart. For example, the pericardium tissue may be engaged
by a number of tissue retractors secured to either anchoring ports
or anchoring mechanisms, according to the present invention, in
order to place the longitudinal axis of the of beating heart in a
substantially vertical orientation to facilitate grafting of the
posterior arteries. A number of tissue retractors comprising a
curved needle 20 and a suture line 23 may pierce the pericardium
tissue close to the base of the heart (or close to the pericardial
reflection): one tissue retractor placed between the superior and
inferior pulmonary vein, a second tissue retractor below the
inferior pulmonary vein, a third one midway between the apex of the
heart and the inferior pulmonary vein, and a fourth one towards the
diaphragmatic face near the inferior vena cava. Retraction loads
are subsequently applied to these tissue retractors, and said
tissue retractors each secured to an anchoring mechanism disposed
on sternum retractor 1 thereby maintaining the desired tissue
retraction, in one of the manners described above, according to the
present invention.
[0171] The above descriptions of the preferred embodiments should
not be interpreted in any limiting manner since variations and
refinements are possible without departing from the spirit of the
invention. For example, the tissue-piercing needle 20 may be either
solid throughout or of a hollow cross-section, the curvature of the
needle may be of any number of variants from almost straight to
slightly curved to curved, cross section can be circular or
elliptical or have a local flat spot, along the curved length of
the needle, to improve the stability of the clamped needle within
the mating jaws of a surgical clamp used while piercing tissue or
some other manipulation with the tissue retractor. The wire-like
filament 23 may be of various lengths, diameters, material, braided
or multi-stranded fabrication, or even made from a silastic
material. As well, the suture contacting surfaces of the components
of the anchoring mechanism which cooperate to clamp, pinch, or
retain the portion of suture line 23 may be textured or otherwise
treated to tend to improve the friction between said suture line
and said suture contacting surfaces.
* * * * *