Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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TITLE: SURGICAL RETRACTOR ELEMENTS ANr~ ASSEMBI,Y
This invention relates to surgical devices and more particularly to
surgical retractor paddles and associated elements used to hold an incision
5 open and to hold back (retract~ adjacent tissues (e. g.: bowel) allowing
exposure of organ(s) requiring surgery,
Over the years numerous types o~ surgical retractors have been
developed to hold an incision open during the surgical operation by holding
uninvolved tissue (including skin, fat, muscle, nerves and organs~ behind
1 o various types of blades or paddles; a cavity being produced in which a
surgical procedure can be executed with the required good vision for precise
technique. Retractors are also used to hold the border of the incision
stable .
Many of the retractors have included a ring or circular element.
1 5 Several angularly positioned paddle shaped retractor elements mount to the
ring element and project into the incision to hold the incision open and to
barricade the invasion of uninvolved tissues into the surgical cavity.
Several retractor arms have been constructed that allow adjustment of
the opening of the incision. Such arms may be adjusted by tightening or
;~0 loosening some type of screw or clamp elements that are fixed to the ring
portion. Examples of such retractors are illustrated in U . S . Patents
2,623,517, granted to I.O. Barlow et al on December 30, 195~; 2,893,378,
granted to R.L. Cooper on ~uly 7, 1959; 3,040,739, granted to H.R.
Grieshaber on June 26, 1962; and 3,384,078, granted to W . K . Gauthier on
May 21, 1968. Several of the surgical retractors have been of the
self-retaining type. Included is a paddle or hook with a lip that extends
outward underneath the body tissues. The paddle maintains the retractor in
position and prevents the retractor ~rom migrating during the surgical
process . Examples of such paddle elements are illustrated in U . S . Patents
2,623,517 (mentioned above) aad 3,394,700, granted to Hideo Yamamoto July
30, 1968.
The typical retractor paddle is formed of a stainless steel or reinforced
plastic material that has a curved surface for engaging the body tissues.
An example of such a blade or paddle is illustrated in U . S . Patent 3,384,078
3 5 (above mentioned) .
The devices described above have been known to press upon nerves,
producing damage and paralysis. Additionally, the surgeon must be careful,
when expanding the incision to not trap bowel or body organs beneath the
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edges of the paddles or hooks. Otherwise the tissue might be damaged.
Additionall~v, the paddles are rig~id and unforgiving, placing substantial
stress concentration on the body tissues. The potential for trauma is
thereby increased and may increase the recovery time for the patient. In
the l~nited States millions of surgeries are performed each year utilizing
surgical retractors. A savings of one day of recovery time would represent
a very significant decrease in the cost of hospitalization and patient
discomfort .
Additionally, absorbent cotton materials (called sponges) are generally
used in conjunction with surgical retractors to pack away uninvolved tissues
so as to not impede the progress of the operation. Sponges can contribute
to tissue dehydration. Sponges are occasionally left in the ~bdomen after
the surgery is completed and the incision closed. Sponge retention often
causes severe complications . Furthermore ~ sponges are carriers of a
variable degree of lint. Lint alone, when retained in the abdominal cavity
can cause irritation, inlqnmm~tion, and adhesions which may result in
prolonged discomfort, or severe complications.
One of the principal objects of this invention is to provide surgical
retractor elements that are capable of engaging and holding back the
;~ O uninvolved body tissues from the site or locus of the operation while
min;mi~ing stress concentrations on the abdominal wall and materially
reducing the potential for trauma tQ tissues held out of the surgical cavity
by the retractor paddle.
A further object of this invention is to provide stable surgical retractor
2 5 elements that are capable of being readily manipulated and adjusted by the
surgeon or an assistant.
A further object of this invention is to provide versatile surgical
retractor elements which permit a reduction in members of the surgical team.
Additionally, fewer assistants may be required which reduces the surgical
3 0 costs .
A further object of this invention is to provide surgical retractor
elements that are capable of significantly reducing body tissue trauma and
thereby reduce recovery and hospitalization time.
A further advantage of this invention is to provide surgical retractor
3 5 elements that are highly adjustable, enabling the system to be utilized on a
wide variety of patients having a wide diversity in flesh thickness and body
cavity depth.
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A still further object of this invention is to provide surgical retractor
elemen ts that reduce the need or sponges .
These and other objects and advantages of this invention will become
apparent upon reading the i'ollowing detailed description.
The present invention is illustrated in the accompanying drawings, in
which:
Fig. 1 is a pictorial view of a paddle for mounting to an existing form
of retractor;
Fig. 2 is a side elevation of the paddle shown in Fig. 1 mounted to an
existing form of hand-held retractor;
Fig. 3 is a rear view of the paddle and retractor shown in Fig. 2;
Fig. 4 is a side view of' a hand-held form of the retractor assembly;
Fig. 5 is a cross-sectional fragmentary detail view of a portion of the
assembly taken along line 5-5 in Fig. 4;
Fig. 6 is a top plan view of the assembly shown in Fig. 4;
Fig. 7 is a plan view of a self-retaining surgical retractor showing
present retractor elements and a retractor assembly utilized in conjunction
with abdominal surgery on a patient;
Fig. 8 is a vertical cross--sectional schematic view taken along line 8-8
;~0 in Fig. 7 illustrating a lateral paddle assembly;
Fig. 9 is a vertical cross-sectional schematic view taken along line 9-9
in Fig. 7 illustrating a polar paddle assembly;
Fig. 10 is a vertical cross-sectional schematic view taken along line
10-10 in Fig. 7 illustrating a lap paddle assembly;
Fig. 11 is a vertical cross-sectional view taken along line 11-11 in Fig.
7 illustrating a one-directional adjustment locking mechRni~m;
Fig. 12 is a view similar to Fig. 11 showing the release of the locking
mechanism;
Fig. 13 is a vertical cross-sectional view taken along line 13-13 in Fig.
3 0 9 illustrating a vertical adjustment mechanism for adjusting the paddles with
respect to the patient;
Fig. 14 is an isometric view of a lateral paddle member illustrated in
Fig. 8,
~ig. 15 is a horizontal cross-sectional view taken along line 15--15 in
3 5 Fig- 14;
Fig. 16 is an isometric view of a polar paddle member illustrated in Fig.
9;
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Fig. 17 is a horizontal cross-sectional view taken along line 17-17 in
Fig. 16;
Fig. 18 is an isometric view of a lap paddle member illustrated in Fig.
10; and
Fig. 19 is a cross-sectional view taken along line 19-19 in Fig. 18.
Several forms of the present surgical retractor elements and assembly
are shown in the accompanying drawings. Specifically, Figs. 1 through 3
show one form of the present retractor pad~le that is adapted to be mounted
on a conventional hand-held retractor. Figs~ 4 through 6 show a form of
the present hand-held retractor assembly, including a hand-held frame and
paddle. A form of the present assembly is also shown in conjunction with a
self-retaining retractor assembly in Figs. 7 through 19.
All forms of the present retractor elements and assemblies are intended
for surgical use on an animal or human body 13 ( Figs . 4, 7, and 8 through
10) to hold a surgical incision open. The primary object of the retractor
elements and assemblies is to hold the incision open, allowing a surgeon to
effectively and efficiently perform a surgical procedure within a surgical area
14. As shown in Fig. 7, the incision is made in the abdominal area of the
body 13. The present retractor elements and assemblies operate to hold
;~ O back body "tissues" adjacent the incision . For purposes of this disclosure,
the purposely generalized term "tissues" will be taken to include body wall
flesh 16 (including skin, fat, muscle, and nerve tissues) and the body
viscera 18.
One form of a retractor paddle element of the present invention is
shown particularly in Figs 1 through 3 at 10. This particular element of the
present invention is adapted for mounting to conventional hand-held
retractors such as that shown at 20 in Fig. ~.
Conventional hand-held retractors 20 ma~y be formed either of an
integral handle 21 and blade 23 as shown, or can include a solid cast handle
and a stiff wire blade (not shown). In surgery, the "blade" is inserted into
an incision and is positioned adjacent tissues desired to be held away from
the surgical area 14. The task of holding the blade in place and providing
sufficient force against the blade to hold the uninvolved tissues away from
the area 14 is typically assigned to an assistant. Often several such
3 5 retractors are used, along with an equal number of assistants . Also, such
hand-held retractors are commonly used in conjunction with self-retaining
retractors for specific, localized applications within the surgical area.
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The illustrated paddle 10 includes a body 2~ forrrled entirely of a soft,
resilient, non-metallic, non-absorbent rnaterial such as ureth~ne, vinyl,
rubber or other appropriate material. The material is scissile, allowing the
surgeon to quickly and easily cut the paddle into any size or configuration
5 desired.
The material used for the paddle 10 and for the other paddle forms
shown and described below is soft and flexible with an operable flexural
modulus of elasticity range between 1,000 psi and 75,000 psi. Preferably,
however, the range is between 2,000 psi and 20,000 psi . The operable
l o "softness" durometer range of the material is softer than D-69 Shore but
harder than A-20 Shore. The preferable range, however, is softer than
A-99 Shore and harder than A-60 Shore.
The material is thus sufficiently soft and resilient to allow the paddle
body 2~ to bend into an arc, evenly distributing forces to the eng~ged
1 5 tissue without producing stress concentrations that would otherwise be likely
to damage or traumatize the affected tissues.
The paddle body 24 includes a front face 25 that is adapted to engage
body tissues including the body wall flesh 16 and viscera 18. The body 24
also has a back face 26 that is adapted to face inwardly toward the surgic~l
;~0 area 14. The faces 25 and 26 extend to peripheral side edges 27. The
edges 27 are preferably upright and joined by a peripheral top edge 28 and
an opposed bottom edge 29.
The paddle body 24 includes a thickness dimension between the front
and back faces that decreases from the central portion toward side edges 27.
25 The thickness dimension preferably decreases toward the bottom edge 29.
The decreasing paddle thickness feature, coupled with the material
characteristics described above, allow the body 24 to deflect resiliently into
two dimensional arcs between edges 27 and edges 28 and 29 in response to
forces applied thereto.
The body 24 includes one or more thick central sections 30 and thin
peripheral skirt sections 31 leading to the edges 27 and 29. The thin
peripheral sections are scissile, allowing the surgeon to cut the paddle to
any desired shape or size according to need.
The thick central sections 30 include means at 32 along the back face of
3 5 the body adapted to mount a retractor frame, such as the retractor blade 23
of Fig. 2. A vertical slot 34 is formed lengthwise through the thick central
sections 30 of a shape that is complementary to the cross-sectional
configuration of the blade 23. The blade 23 is thus slidably received
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through the aligned slots 34. The resilient material conforms intimately to
the curvature of the blade with the peripheral sections 31 ~t the sides
projecting laterally of the blade sides and the skirt section 3 L at the bottom
projecting downwardly beyond the p~ddle end. The blade end is received in
a bottom closed pocket 35 of the means 32. The centr~l portions 30 of the
paddle will conform to and are reinforced by the blade 23. The peripheral
sections 31, however, are allowed to flex resiliently about the retractor
blade. The thin sections 31 are able to bend sharply about short radii and
at angles approaching 90 to the norrnal planar orientation of the faces.
This flexural "give" eliminates stress concentrations that would otherwise
occur at the rigid edges of the conventional blade 23.
It is understood that the retractor 20 shown herein is merely one of
many conventional forms currently in use. It should be understood,
however, that the present paddle structure is sufficiently resilient and
pliable to fit over many blade configurations. Furthermore, the paddle 10
can also be produced with varying shape and size slots 34 to conform to
virtually any retractor blade structure.
Figs. 4 through 19 show modified forms of the paddle described above
for use as an element of (1) a no~el hand-held retractor assembly 40 (Figs.
;~0 4 through 6) and (2) a novel self-retaining retractor assembly 100 (Figs. 7
through 19). In such embodiments, the paddles are preferably included as
elements of retractor assemblies 40 or 100. The paddles 10 themselves,
however, are adjustably mounted to respective mounting means for vertical
adjustment as will be described below.
The hand-held retractor assembly 40 basically includes an integral
paddle mounting arm 41 and hand grip handle 42. Assembly 40 allows a
surgical assistant to comfortably hold an incision open for extended periods
of time without the usual accompanying fatigue so often associated with
conventional hand-held retractors.
The paddle 39 of this embodiment is nearly identical with the ~orm
shown in Figs. 1 through 3 with the exception that a single elongated
central thickened section 43 may be provided in place of the several sections
30 of the Fig. 1 through 3 version.
The mounting arm 41 (Fig. 4) includes a horizontal section 45 and an
3 5 upright section 46 for mounting the paddle 39 . The two sections are shown
at right angles. However, it is understood that other ang~lar relationships
(acute or obtuse) might be utilized as well.
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The upright section 46 may include an adjwstal~le mo~ tirlg means (not
shown) that is sirnilar to that shown in detail by Fig. 13 and described below
for the self-retaining retractor 100. Section 46 mounts the paddle 39 to the
mounting arm 41 for vertical adjustment thereon. Effective penetration of
5 the p~ddle into the body cavity can thus be varied according to need. More
detailed description of a similar adjusting means will be given in conjunction
with the description of the self-retaining retractor lQ0 below.
The hand grip handle 42 includes a first handle section 48 leading up
and outwardly from the arm 41. A second handle section 49 projects
10 downward from the section 48. It is preferable that the first handle section
48 form an obtuse angle with the horizontal section 45 of paddle mounting
arm 41. It is also preferable that the second handle section 49 be
substantially perpendicular to the first section 48.
The first handle section 48 provides a hand grip surface 50. ~he
15 surface 50 facilitates a comfortable grip by one of an assistant's hands. The second handle member likewise has a hand grip surface 51 grasped by the
other of the assistant's hands. The perpendicular relationship of the grip
surfaces to each other and to the arm 41 allows orjentation for superior
mechanical advantages of the assistant's hands to assure a firm grip on the
;~0 retractor and to lessen fatigue.
A hand stop 52 is provided between the first and second handle
sections 48, 49 to abut with the hand gripping the ~irst section. The stop
52 is shaped along the surface 53, facing section ~8, to conform to the side
of a user's hand. Fig. 5 shows the enlarged area of the abutment surface
25 53'
A side of stop 52 opposite surface 53 includes a thumb brace surface
54. The thumb brace surface 54 faces the second section 49 to provide a
surface against which a userls thumb may comfortably rest. The surface 54
is preferably concave to conform to the surface of the thumb (Fig. 6~.
Opposite the thumb brace surface 54 and at a remote end of the handle
is another hand stop 56 (Fig. 4) . The side of the user's other hand bears
against the stop 56. The stop 56 effectively prevents the hand from
slipping off the handle surface 51. Consequently, the assistant's hand
against the surface S1 may be rather relaxed. The stop 56 is hook shaped
35 and extends down and inward to engage the side of the user's hand.
The self-retaining form of the surgical retractor assembly 100
(Figs. 7-12) includes a circumscribing or annular frame or ring member 120
that is made of a rather rigid material for circumscribing the surgicfll area
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14. The frame preferably has a modulus of elasticity greater tllan 300,000
psi .
The retractor 100 further includes a plurality of paddle assemblies 122
that are operably mounted to the ring member 120. The assemblies 122 are
angularly spaced about the surgical area 14 for engaging uninvolved tissues.
The paddle assemblies 122 serve to maintain the incision open without the aid
of an assistant and to facilitate surgical operations without interference from
uninvolved tissues.
Preferably, the ring mernber 120 is made as a unitary member with an
upper ring plate 124 (Figs. 8-12) and a lower ring plate 125 vertically
separated by angularly spaced ribs 127 shown by dotted line in Fig. 7. The
ribs 127 are preferably quite narrow so that an annular slot 129 (Figs. 8-10)
of substantially 360 is formed between the upper plate 124 and the lower
plate 125. The ribs 127 provide rigid support between the plates 124 and
1 5 125. The annular slot 129 extends from an inner face 135 (Figs. 8-10) ofthe ring member 12n to an outer face 136. The annular slot 129 is capable of
receiving a plurality of paddle assemblies 122.
Each of the paddle assemblies 122 includes an arm frame member 140
and a paddle 142 (Fig. 7-10), The arm frame member 140 includes a
;~0 horizontal section 144 that extends radially through the annular slot 129 in a
close sliding fit between the top and bottom ring members 124, 125. In a
preferred embodiment, the horizontal section 144 has a substantially
rectangular cross section so that the paddle assemblies 122 will not rotate
about the horizontal section 144.
Each horizontal section 144 extends from an outer end 145 to an inner
end 146. The inner end 146 forms part of a bend that is integral with an
upright section 148. The section 148 extends downward to a terminal lower
end 150 (Figs 8-10 and 13). The bend illustrated forms an acute angle
between the horizontal section 144 and the upright section 148. Preferably
the acute angle is between 75 and 85 so the paddle 142 will extend
downward and outward with respect to the surgical area 14. It is noted that
though the above angular range is preferred, in some operations other
angles are envisioned, including obtuse angles.
A preferred retractor 100 has three general types of paddles. Such
paddles 142 include lateral paddle members 152 (Figs. 7, 8, 14 and 15) that
are positioned laterally from the axis of the incision or at the 90 and 270
positions with respect to the axis of the body when abdominal surgery is
being performed as illustrated in Fig. 7. The paddles 142 may include polar
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paddle members 155 (Figs, 7, 9, 16 and 17) that may be positioned
perpendicularly to the lateral paddle members LS2. Additionall~J, paddles 142
may include lap paddle members 154 (Figs. 7, 10, 18 and 19) that are
interposed between the lateral members 1~2 and the polar mernbers 155
depending upon the type of operation. When a rather large incision is made
in the abdominal area the lap paddle members 154 may be positioned
intermediate the lateral members 152 and the polar members 155 at the 45
position, the 135 position, and the 315 position. It should be noted that
when all of the paddle members 152, 154 and 155 are utiliz~d, ~ substantially
1 o 360 enclosure is formed which may be referred to as a "coffer dam" to
minimize the intrusion of body viscera 18 into the surgical area.
Consequently, the need for sponges is greatly reduced and possibly
eliminated .
It is preferred that each of the paddles 142, liXe paddles 10 and 39,
1 5 are formed of a non-metallic soft, resilient material that is scissile and
capable of being deformed or flexed to conform to the tissues about the
periphery of the incision. The paddles 142 are preferably interchangeable
with the paddle members 39 shown in Figs. 4-6. The paddles 10, 39 and 142
have the same physical material properties. The paddle members will thus
;~ O conform and flexibly deflect in response to the contours and tensions of the
body tissues. The paddle material will conform in response to the reactive
forces placed upon the paddles as the paddle assemblies 122 are moved
radially outward to spread the incision open and to maintain the surgical
area unobstructed.
Each of the paddles 142 includes a body 157 (Figs. 7, 8-10, 14, 16 and
18) having a front face 156 that is adapted to engage the body wall flesh 16
and viscera 18. The body 157 has a back face 158 that faces the surgical
area 14. The front face 156 and the back face 158 extend outwardly to
peripheral side edges 160, a peripheral top edge 161 and a peripheral bottom
edge 162.
The paddle members 142 have a decreasing thickness from the central
portion toward the side edges 160. The paddle members 142 will thus deflect
in a curved arc in response to the reactive forces placed on the front face
156. During use the front face 156 forms a substantial arc between the
3 5 peripheral side edges 160 with the pressures being distributed over the
front face 156 to minimize stress concentrations. The peripheral side edges
160 are rather thin and quite pliable to enable the edges 160 to
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progressively bend in arcs having small radii of curvnture to minimize and
prevent stress concentrates along the peripheral edges 160.
The back face 158 includes an enlarged section 164 that has a vertical
slot 165 formed therein for slidably receiving the vertical section 148 of the
arm member 140,
Each of the lateral paddle members 152 includes a rather thick central
section 166 and thin peripheral sections 167 leading to the peripheral side
edges 16~.
The lateral paddle members 152 include a retaining projection 168 that
extends outward from the front face 156 terminating in a leading edge 170.
1~ The retaining projections 168 include side edges 172 and 173 that extend
rearward from the leading edge to the central section 166. The retaining
projection 168 has a top surface 174 and a bottom surface 175. The
retaining projection 168 is designed to extend outward from the incision into
the body cavity intermediate the body wall flesh 18 and the body viscera 18.
The top surface 174 is intended to engage the body wall flesh 16. The
retaining projection 168 holds the retractor 1û within the incision and
prevents the retractor 10 from being ejected or dislodged from the incision.
The lateral paddle 152 includes a very minimal skirt 176 that extends
downward a slight distance from the retaining pro~ection 168.
~ The lateral paddle members 152 are principally designed to maintain theinr~ ion in an open position against the tension OI the body wall flesh with
the retaining projection 168 securing the retractor 100 within the incision.
In response to the tension of the tissues the front face 156 of the lateral
member 152 forms an arc against the body wall fle.sh 16 as illustrated in Fig.
2 5 7 to eliminate points of stress concentration . The degree of arc is
dependent upon the width of retraction relative to incision length.
Frequently, the lateral paddle members of conventional retractors press
against nerve elements such as the femoral cutaneous nerves and it is very
important that undue stress concentrations be minimized to prevent nerve
damage. The lateral member 152 illustrated in Fig. 14 has a radius 178
between the central section 166 and the peripheral section 167 so that the
peripheral side sections 167 may readily bend in arcs to prevent sharp
stress concentrations adjacent the edges and thus avoid nerve damage or
damage to other adjacent tissues.
The polar paddle members 155 (Figs. 16 and 17) include a central
section 180 with a peripheral section 181 extending outward to the peripheral
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side edges 160 and the peripheral bottom edge 162 as illustrated in Figs . 16
and 17.
The polar paddle members 155 include a retaining projection 182 that
extends outward from the central section 180 to a leading edge 184.
Preferably, the retaining proiection 182 is considerably shorter than the
re~aining projection 168. The retaining projection 182 has side edges 186
and 187 extending rearward from the leading edge to the central section 180
forming a top surface 188 and a bottom surface 189. The top surfaee 188 is
intended to fit immediately underneath the body wall flesh 10 as illustrated
in Fig. 9.
The polar paddle members 155 each include a skirt section 190 (Figs. 9
and 16) that extends downwardly a substantial distance from the projection
182 for bearing against the body viscera to hold the organs from the
surgical area 14. As illustrated in Figs. 16 and 17, the polar paddle
members 155 each have a radius 191 formed in the front face 156 between the
1 5 central section 180 and the peripheral section 181. The radius 191
substantially decreases the thickness of the polar paddle members 155
adjacent the peripheral side edges 160 and the bottom edges 162. It should
be noted that the peripheral sections 181 adjacent the bottom edges 162 are
capable oE bending at least 90 without breaking so that the bottom edges
162 do not press dangerously against any nerve, vein, artery, ureter, or
other body tissue elements. This feature is very important in preventing
nerve and tissue damage, blood clots, arterial occlusion, or kidney
obstruction via the ureteral drainage conduit.
Each of the lap paddle members 154~ illustrated in ~igs. 18 and 1g.
includes a central section 192 and a peripheral section 193 extending outward
from the central section to the peripheral side edges 160 and bottom edge
162, Preferably the lap paddle members 154 are without any retaining
projections and are principally designed to interlace between the lateral
paddle members 152 and the polar paddle members 155 to engage and
3 maintain the body viscera 18 ~rom the surgical area 14. ~ach member 154
has a skirt 195 that extends downward a substantial distance into the body
cavity to provide a barrier to the body viscera. A radius 194 is formed on
the back face 158 of each lap paddle member 154 so that the peripheral side
edges 160 thereof may overlap the adjacent peripheral side edges of the
adjacent lateral paddle member 152 and polar paddle member 155 as
illustrated in Fig. 7. The peripheral sections 167, 181 and 193 substantially
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overlap and form a sliding seal to reduce the exposecl tissue surface area
and resulting dehydration.
It should be noted that not all operations will require the use of the lap
paddle members 154. However, they are quite useful, as are the other
5 paddle forms, particularly as a substitute for sponges. They help prevent
the loss of sponges within the body cavity and complications from lint
deposition. Additionally, the paddles do not absorb body liquids (as do
sponges), but leave the tissues in a more natural state with less
dehydration. Such attributes p~ovide for quicker patient recovery.
1 0 Each OI the paddle assemblies 122 (&nd the hand-held retractor 40
described above) includes a vertical adjusting means 196, (Fig. 13) for
vertically adjusting the paddle members l42 with respect to the arm members
140. Such a feature is illustrated in Fig. 13. The vertical adjusting means
196 includes rigid detent projections 198 formed on side edges of the vertical
1 5 arm sections 148. Complementary series of recesses 200, formed in the
vertical slots 165, enable the detent projections 198 to be received therein.
Together they secure the paddle members 142 at a variety of desired
elevations with respect to the horizontal arm sections 144. As illustrated in
Fig. 13, the detent projections 198 extend below the enlarged sections 164
;~0 when the paddle member is located in uppermost position. The paddle
assemblies 122, being two separate pieces, 142 and 140, allow the use of
different length paddle members 1~2 providing additional vertical adjustment.
Each of the paddle assemblies 122 further includes radial adjustment
means 202 (Figs. 1:L and 12) for enabling the paddle assemblies 122 to be
quickly and easily radially adjusted with respect to the ring member 120.
Preferably the radial adjustment means 202 includes a releasable
one-directional locking means 204 that operatively interconnects the
horizontal section 144 of the arm member 140 and the ring member 120. The
locking means 204 preferably includes a series of ratchet teeth 206 formed in
the upper surface of the horizontal section 144 adjacent to the outer end
145. Each of the ratchet teeth 206 includes an abutment surface 207 that is
preferably inclined inward toward the inner end 146, forming an acute angle
of approximately 85 with the horizontal section 144 of the arm member 140
and an inclined or ramp surface 2û9 that faces outward towards the outer
end 145. A wide groove 210 is formed between the teeth 206. The wide
groove 210 sllows pivotal movement of the arm assemblies 122. The grooves
210 and the teeth 206 are preferably formed in arcs with respect to the
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center of the ring member 120 so that the arm members may slide
circumferentially without releasinK the locking means 204.
The locking means 204 further includes a plurality of biased pawls 212
(Figs. 7, 11 and 12) that are positioned about the outer face 136 of the ring
5 memberl20. The biased pawls 212 are adjacent to each other and
interconnected to the main portion of the upper ring plate 124 through a
flexible web section 213. The web section 213 biases the pawls 212
downwardly to engage the teeth 206. The pawls 212 and the teeth 206 are
designed so that the paddle assemblies 122 may be moved outwardly very
10 easily by merely applying a radial force on the paddle assemblies 122 causingthe horizontal section 144 to slide outward in the annular slot 129. The
pawls 212 ride up the inclined surfaces 209 and then fall downwardly into
the grooves 210 immediately adjacent the abutment surfaces 2~7. The pawls
212 have contact surfaces 208 that engage the abutment surface 207.
1 5 Contact surfaces 208 are formed at acute angles of approximately 85 in
relation to the lower surface of the upper ring plate 124. Such angled faces
208 mate with the angled abutment faces 207, enhancing the security of the
locking means 204. When the desired position is reached the pawls engage
themselves and the mating surfaces prevent the paddle assemblies 122 from
moving radi~lly inward unless the locking means 204 is intentionally released.
It should be noted that the biased pawls 212 are sufficiently close to
each other to enable an arm 140 to be moved circumferentially about the
center of the ring member 120 from one pawl 212 to an adjacent one without
releasing the arm 140 or enabling the arm 140 to move inwardly. Such a
25 feature provides a great deal of versatility and enables a surgeon or his
assistant to readily adapt the angular positions of the paddle assemblies 122
to a particular circumstance and portion of the body. This can be done
without having to first release the paddle assembly 122, move the paddle
assemblies and then reset the locking means.
It should be particularly noted with respect to Fig . 7 that the paddle
members 142 form a substantially uniform arc and curvature with the front
faces 156 of paddles 142 minimi~ing or preventing the formation of stress
concentrations at the edges 160 of the paddle 142.
Experimental evidence indicates that the present retractor elements and
3 5 assemblies described above substantially reduce body tissue trauma and
minimi2e the damage to nerves which may cause paralysis. It appears that
the recovery rate of patients enjoyin~ the experimental use of the present
invention is enhanced. Experimental evidence also shows that the present
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retractor elemerlts and assemblîes, compared to conventional instruments,
greatly aid the surgeon in significantly decreasing the amount of time and
the number of assistants required for surgery, particularly on very obese
patients .
It should be understood that the above description is simply illustrative
of the principles of this invention and that numerous other embodiments or
modifications thereof may be devised that fall within the scope of the
invention set forth by the following claims.
What is claimed is:
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