Minimally invasive retractor for internal mammary artery harvesting

An intermammary harvesting retractor comprised of a retractor frame having a fixed or stationary arm on one end of a crossbar and a movable arm mounted on the crossbar by a crank mechanism. The crank mechanism allows the movable arm to be adjusted toward or away from the stationary arm. A support tower is mounted on the free end of the retractor crossbar to allow the angle of the retractor to be adjusted after placement in an incision. The angular adjustment allows the upper portion of a patient's ribcage to be lifted to provide improved access and visualization to the intermammary artery. Adjustable lifter blades are provided on the movable arm to also adjust the lift angle of the upper ribcage. One embodiment has an adjustable lifter blade that can be adjusted after placement in the incision and adjustment of the angle of the retractor crossarm. Another embodiment employs a self-adjusting blade that is pivotally mounted in hangers provided on a lifter blade receiver coupling fitting on the end of the movable arm. The construction and arrangement of the invention allows the placement of the retractor and adjustment of the angle of the retractor by the support tower to lift and retract a patient's upper ribcage to allow improved visualization of the intermammary artery to harvest the intermammary artery for use in heart bypass procedures.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to retractors for use in heart surgical procedures 
and more particularly relates to retractor for harvesting an internal 
mammary artery for use in heart bypass surgery. 
2. Background Information 
Surgical retractors are used in variety of surgical procedures such as open 
heart surgery for performing heart bypass operations. Doing these 
operations a suitable replacement for a clogged artery is needed. Often 
these arteries are taken from various parts of the human body but one 
commonly used artery is the internal mammary artery. 
The internal mammary artery is found in the tissue beneath the ribcage 
immediately above and adjacent to the heart. A few centimeters in length 
is usually removed to be grafted to a clogged artery in the heart. Since 
this artery is embedded in the soft tissue beneath the ribcage, it is 
sometimes difficult to remove the graft. 
To perform this procedure an incision must be made between ribs of the 
ribcage and the upper portion of the ribcage lifted to provide access to 
the internal mammary artery. However since the internal mammary artery 
traverses the soft tissue in the ribcage it is difficult to see. Presently 
available retractors do not allow a clear view or ready access to the 
internal mammary artery. 
It is therefore one option of the present invention to provide a 
cardiovascular retractor for internal mammary artery harvesting. 
Still another object of the present invention is to provide a 
cardiovascular retractor having a versatile design to accommodate patient 
anatomies and surgeon's techniques. 
Still another object of the present invention is to provide a chest 
retractor having a support tower or stand that allows an improved angle of 
retraction for internal mammary artery visualization. 
Still another object of the present invention is to provide chest retractor 
for internal mammary artery harvesting having a self-adjusting blade for 
lifting the ribcage. 
Yet another object of the present invention is to provide a chest retractor 
for internal mammary artery harvesting having an adjustable lifter blade 
to adjust the angle of retraction for internal mammary artery 
visualization. 
BRIEF DESCRIPTION OF THE INVENTION 
The purpose of the prevent invention is to provide an improved chest 
retractor for use in internal mammary artery harvesting that provides an 
improved angle of retraction to allow internal mammary artery access and 
visualization. 
The improved chest retractor is comprised of a slide retractor frame having 
a cross bar with a stationary or fixed arm at one end and a movable arm 
adjustable by a crank mechanism to read the spacing between the arms and 
the amount of retraction. The retractor frame is comprised of the cross 
bar having a rack gear and a stationary or fixed retractor arm at one end. 
A second movable retractor arm is adjustably attached to the cross bar and 
has a crank mechanism for moving the arm toward or away from the fixed arm 
to vary the spacing. The crank mechanism is disclosed and described in the 
U.S. Pat. No. 5,167,223 issued Dec. 1, 1992 to T. Koros et al and is 
incorporated herein by reference. Each arm has an end constructed for 
receiving a coupling on a blade for removably mounting a variety of 
retractor blades. 
The fixed arm has a pair of flanges adapted to fit a slot in the coupling 
on a standard retractor blade. The coupling on the standard blade is 
formed with a flange having a socket for receiving the flanges on the free 
end of the fixed or stationary arm. The movable arm is also constructed 
with a pair of flanges that fit a lifter receiver coupling or for mounting 
a variety of retractor lifter blades. The lifter receiver or coupling also 
has a pair of curved hangers. A swinging, self-adjusting lifter blade is 
constructed with pins that fit the hangers to mount the self-adjusting 
blade on the lifter blade receiver which is mounted on the end of the 
movable arm. A screw clamps the blade mounting lifter blade receiver on 
the end of the movable arm. 
The blade mounting lifter blade receiver has a configuration on the hangers 
for receiving the flange on an adjustable lifter blade. The mounting 
flange on the adjustable lifter blade hooks around the center portion of 
the blade mounting coupling between the hangers which assist in 
positioning the adjustable lifter blade. 
The pins on the self-adjusting blade engage the hangers allowing the blade 
to swing freely so that the blade self adjusts when the tilt angle of the 
retractor is varied as will be described hereinafter. 
In an optional but preferred embodiment an adjustable lifter blade assembly 
is provided in which a hinged swinging deep retractor lifter blade has a 
mechanism for manually adjusting the angle of the blade. The adjustable 
lifter blade assembly is comprised of the blade mounting coupling having a 
configuration for receiving a blade mounting flange on the adjustable 
lifter blade. The blade mounting flange fits between the hangers and wraps 
around the center portion of the lifter blade mounting coupling. The 
adjustable blade is hingedly mounted on the end of a flange plate on the 
blade mounting flange. The adjustable lifter blade is mounted by a pin 
passing through a pair of ears on the blade which passes through a bore in 
the end of the flange plate. 
An extension on the adjustable lifter blade forms a ledge beneath flange 
plate. A screw mounted on the ledge extends through the flange plate. A 
wing nut on the screw adjusts the spacing between the ledge and the flange 
plate to adjust the angle of the swinging or hingedly mounted adjustable 
lifter blade. 
The hingedly mounted adjustable lifter blade has a curved portion extending 
to a tapered tongue constructed to fit beneath the ribcage of a patient. 
One side of the tapered tongue is cut at an oblique angle to align with 
the intermammary artery. This oblique angle of the tapered tongue allows 
the surgeon to place the blade along the intermammary artery but without 
interfering with the surgical procedure to harvest the artery. 
A tower or stand is provided to adjust the angle of the retractor when 
placed in an incision to allow the upper portion of the chest to be lifted 
so that a surgeon may see the intermammary artery in the tissue beneath 
the ribcage. The tower is comprised of a support bar mounted on the free 
end of the retractor cross bar opposite the stationary or fixed arm and a 
support shaft or tower adjustably connected to the support bar with a 
connecting clamp. A footpad on the end of the support tower rests on the 
surface of the patient's chest when the intermammary artery harvesting 
retractor is placed in the incision. Adjustment of the height of the tower 
allows the angle of the retractor to vary. Raising the tower lifts the 
free end of the cross bar adjusting the angle of the retractor allowing 
the upper ribcage to be lifted for improved access and visualization of 
the intermammary artery. The self-adjusting lifter blade connected to the 
lifter blade receiver coupling swivels or pivots in its mounting to self 
adjust to the angle of the retractor. 
More flexibility in adjusting the angle of the retractor visualization of 
the intermammary artery is provided with the combination of the adjustable 
tower and an adjustable lifter blade. The tower may be adjusted to adjust 
the angle of the retractor to lift the upper ribcage to provide access and 
visualization to the intermammary artery. The adjustable lifter blade can 
then also be adjusted to lift the ribcage. The tower and the adjustable 
lifter blade can be alternately adjusted until the proper angle of access 
and visualization is provided to the surgeon for harvesting an 
intermammary artery. 
The retractor is placed in an incision with the arms substantially closed 
and a standard blade mounted on the stationary fixed arm and the 
self-adjusting swinging lifter blade or adjustable lifter blade mounted on 
the movable arm. The crank mechanism is then operated to spread the 
incision sufficiently to provide access to the intermammary artery. The 
tower may then be adjusted to increase the angle of the retractor to lift 
the upper ribcage of the patient providing improved visualization and 
access to the intermammary artery. If the adjustable lifter blade is used 
it may then be adjusted with the thumbscrew to improve the angle of 
access. 
The above and other novel features of the invention will be more fully 
understood from the following detailed description and the accompanying 
drawings, in which:

DETAILED DESCRIPTION OF THE INVENTION 
A retractor for placement in incision for harvesting an intermammary artery 
is shown generally in the isometric view of FIG. 1. Intermammary 
harvesting retractor 10 is comprised of cross bar 12 having a rack gear 
14, a stationary or fixed arm 16 for mounting a standard blade 15 and 
movable arm 18. Stationary arm 16 is provided with an offset 20 to 
accommodate adjustable lifter blades attached to the end of movable arm 18 
as will be described hereinafter. 
The position of movable arm 18 relative to stationary or fixed arm 18 is 
adjusted by means of a crank mechanism 22. Crank mechanism includes a gear 
(not shown) engaging gear rack 14 that is operated by crank handle 24 as 
is disclosed and described in U.S. Pat. No. 5,167,223 issued Dec. 1, 1992 
to T. Koros et al and incorporated herein by reference. A quick release 
locking mechanism 26 locks the movable arm 18 in an adjusted position and 
allows the arms to be quickly closed prior to placement in an incision. By 
closing the handles of quick release locking mechanism 26 the gear is 
released from rack gear 14 allowing movable arm 18 to be quickly moved 
along crossbar 12 toward fixed arm 16. When released the gear is then 
again engaged on rack gear 14 for adjustment by rotation of crank 24. 
A very important function of the retractor of the present invention is to 
provide improved access and visualization for harvesting intermammary 
artery used in heart bypass surgery. A section of the intermammary artery 
is removed and then used for bypassing a blockage of an artery supplying 
blood to the heart. This allows the surgeon to perform heart bypass 
surgery with one operation and through a single incision rather than other 
methods where arteries are taken from other parts of the body requiring 
two or more separate surgical procedures. However the intermammary artery 
is not easily accessible because if is in the tissue just beneath the 
ribcage. Presently harvesting this intermammary artery is a difficult and 
time-consuming task which is disadvantageous because it is important that 
surgical procedures be completed efficiently and as quickly as possible to 
minimize trauma to the patient. Therefore the retractor of the present 
invention has been created to provide improved access and visualization of 
the intermammary artery. 
To achieve this result the retractor of the present invention provides a 
construction that allows the upper ribcage to be lifted providing an 
improved access and view to the tissue just beneath the ribcage. This 
improved access is provided by a retractor having adjustable blade 
assembly 28 and an adjustable tower or stand 30 which will be described in 
greater detail hereinafter. Adjustable lifter blade assembly 28 is 
comprised of a lifter blade receiver coupling 32 fitting on flanges 34 on 
the end of movable arm 18. Adjustable lifter blade coupling 32 has a 
clamping screw 36, a pair of hangers 38, and a center portion 40 for 
receiving adjustable lifter blade mounting flange 42. 
Adjustable lifting blade mounting flange 42 has flange plate 44 for 
hingedly mounting adjustable lifter blade 46 by pin 48 fitting through 
ears 50 and an aperture in the end of flange plate 44 allowing lifter 
blade 46 to freely swing about the axis of pin 48. Hingedly mounted 
adjustable lifter blade 46 has a curved portion 52 and a tapered blade 
portion 54 that will be described in greater detail hereinafter. 
Adjustable lifter blade extension 56 provides a ledge for mounting 
adjusting screw 58 which receives a wing nut 60. Adjustment of wing nut 68 
on screw 58 varies the spacing between ledge 56 and flange plate 44 to 
adjust the angle of adjustable lifter blade 46 as will be described in 
greater detail hereinafter. 
To lift the upper ribcage the angle of retractor 10 must be adjusted. The 
angle of retractor 10 is adjusted by lifting free end 62 of crossbar 12 
which in turn lifts the upper portion 64 of a patient's ribcage allowing 
the surgeon improved access and a better visibility of the tissue beneath 
ribcage. Adjustment of the free end 62 of crossbar 12 is provided by 
support tower assembly 30 comprised of support bar 64 mounted on free end 
62 of crossbar 12 by clamp 66 and support tower or stand 68 mounted on 
support bar 64 by clamp 70 clamped by thumbscrew 72. Support stand or 
tower 68 has a footpad 74 that rests on the patient's chest. The length 
and position of support tower or stand 68 is adjusted by loosening 
thumbscrew 72 and lifting free end 62 of crossbar 12 to lift upper ribcage 
64 and is then reclamped by tightening thumbscrew 72 as will be described 
in greater detail hereinafter. 
The construction of adjustable lifter blade and its operation is 
illustrated in FIG. 2. Swinging adjustable lifter blade 28 has a flange 42 
forming a groove 44 that fits around center portion 40 of lifter blade 
receiver coupling 32 that slides on flange end 34 of movable arm 18 and is 
clamped by screw 36. Adjustable lifter blade flange 42 has a plate 44 
having a slot 45 for receiving screw thread 58 mounted on ledge 56 
provided by an extension of swinging adjustable lifter blade 46. Wingnut 
60 allows the spacing between ledge 56 and flange plate 44 to be varied to 
vary the angle of hinged adjustable lifter blade 46 as is illustrated in 
FIG. 3. 
With retractor 10 placed in an incision, lifter blades to lift the upper 
chest to provide access to intermammary artery 65 that is in tissue just 
beneath ribcage 64. As shown in FIG. 3, adjustable lifter blade 46 fits in 
incision beneath upper ribcage 64. As the tilt angle of the retractor is 
increased adjustable lifter blade 46 may be adjusted by rotating wingnut 
60 on threaded screw 58 varying the space between ledge 56 and flange 
plate 44 to increase the angle of the upper ribcage 64 providing improved 
access and visualization of the intermammary artery 65. 
In some cases it may be suitable to provide a self-adjusting lifter blade 
76 that is attached to movable arm 18 by pins 78 that engage hangers 38 on 
lifter blade receiver coupling 32. This arrangement allows self-adjusting 
blade 76 to swing freely on lifter blade receiver coupling 32 to self 
adjust according to the angle of the retractor and thus movable arm 18. As 
the free end 62 (FIG. 1) of retractor 10 is lifted, self-adjusting lifter 
blade 76 adjusts to lift the upper portion of ribcage 64 providing 
improved access to intermammary artery 65 allowing the surgeon to more 
easily and readily harvest a section of the artery. 
The unique feature of each of the adjustable lifter blade 46 and 
self-adjusting blade 76 is the provision of a tongue on the blades that 
allow precise alignment with the intermammary artery. As shown in FIG. 3, 
tongue 54 on adjustable lifter blade 46 is tapered and has the left side 
55 cut at an oblique angle to be aligned with intermammary artery 65. 
Likewise self-adjusting lifter blade 76 has a tongue 78 having the left 
side 75 cut at an oblique angle also to be aligned with intermammary 
artery 65. This precise oblique angle allows the intermammary harvesting 
retractor to be placed properly with minimum interference and improve 
access to the intermammary artery. 
The assembly of the intermammary artery harvesting retractor is illustrated 
in an exploded view of FIG. 5. Crossbar 12 and fixed arm 16 form a frame 
for retractor 10. Movable arm 18 is mounted on crossbar 12 by engaging 
slot 19 in crank mechanism 22 so that gear 14 engages gear (not shown) in 
gear mechanism 22. Release of lock 26 allows movable arm 18 to slide 
freely on crossbar 12 toward stationary or fixed arm 16. Release of lock 
mechanism 26 engages gear in gear rack 14 for adjustment by crank arm 24. 
Rotation of crank arm 24 moves movable arm 18 away from stationary arm 16 
which remains locked in the adjusted position. A standard blade 15 is 
mounted on end 11 of fixed arm 16 by engaging a C-shaped socket in 
coupling 13. Leaf spring 17 in coupling 13 firmly holds standard blade 15 
on fixed arm 16. The ends of fixed arm 16 and movable arm are found with 
inverted T-shaped tongues 11 and 34 that engage C-shaped grooves or 
sockets on blade 15 or blade mounting coupling 32. 
Adjustable lifter blades are mounted on movable arm 18 by lifter blade 
receiving C-shaped socket in coupling 32 that engages flange end or 
inverted T-shaped tongue 34 of movable arm 18 and is locked in place by 
screw 36. Adjustable lifter blade 46 is then fitted around the center 
portion 40 of lifter blade receiver coupling 32 with groove 44 of blade 
mounting flange 42 fitting around center portion 40 between hangers 38 
which properly position blade mounting flange of adjustable lifter blade 
46. Wingnut 60 is then mounted on threaded screw 58 for adjusting the 
position of adjustable lifter blade 46 by varying the spacing between 
ledge 56 formed by an extension on adjustable lifter blade 46 and flange 
plate 44. 
Adjustable tower assembly 30 is assembled by clamp 66 fitted on end 62 of 
crossbar 12 with a tab engaging a slot 63. This securely locks support bar 
64 on retractor 10. Support tower or stand shaft 68 is then attached to 
support arm 64 by clamp 70 having holes 71 and 73 for receiving ends of 
support bar 64 and tower shaft 68 respectively. Screws 77 in the ends of 
support bar 64 and tower shaft 68 prevent clamp 70 from slipping off the 
respective shafts. Thumbscrew 72 securely clamps tower shaft 68 on support 
bar 64 and allows an adjustment of the position and length. Loosening of 
thumbscrew 72 allows horizontal adjustment along support bar 64 and 
vertical adjustment of tower shaft 68. 
The placement of the intermammary harvesting retractor and adjustments are 
illustrated in FIGS. 6 and 7. Intermammary harvesting retractor 10 is 
assembled as shown in FIG. 5 and movable arm 18 released by closing 
locking mechanism 26 to allow movable arm 18 to slide to a fully closed 
position adjacent stationary of fixed arm 16 illustrated in phantom in 
FIG. 6. Standard blade 15 and adjustable lifter blade 46 are then placed 
in the incision and crank arm 24 rotated to operate crank mechanism 22 to 
move movable arm 18 away from stationary arm to retract the ribcage and 
tissue to spread incision 90 as shown in FIG. 1. Tower assembly is then 
adjusted by loosening thumbscrew 72 allowing support tower 68 to be moved 
horizontally along support bar 64 as well as vertically in clamp 70. Free 
end 62 of retractor 10 is lifted to lift upper ribcage 64 and support 
tower 68 adjusted vertically and horizontally to hold the retractor frame 
at the precise adjusted angle. Support tower assembly 30 is then securely 
clamped by tightening thumbscrew 72. Adjustments of support tower assembly 
30 are illustrated in FIG. 7. Support tower can be adjusted horizontally 
along support bar 64 vertically in support clamp 70 or an angular 
adjustment may be made by rotating clamp 70 on support bar 64 as shown in 
the two positions illustrated in phantom. This permits wide variety of 
adjustments of retractor 10 to improve access and visualization of the 
intermammary artery beneath ribcage 64. 
Adjustable lifter blade 46 may now be adjusted by rotating wingnut 60 on 
threaded shaft 58 to vary the spacing between flange plate 44 and ledge 56 
extending from adjustable lifter blade 46. Support tower assembly 30 and 
adjustable lifter blade assembly 28 may be alternately adjusted until 
optimum position of retractor 10 is achieved and in the best possible 
access to the intermammary artery 65 beneath upper portion of ribcage 64 
is achieved. 
In some cases self-adjusting lifter blade 76 may be substituted for 
adjusted lifter blade 46. Self-adjusting lifter blade 76 will be mounted 
on movable arm 78 by pins 78 that engage hangers 38 allowing 
self-adjusting lifter blade 76 to pivot freely on movable arm 18. As the 
angle of free end 62 of retractor 10 is increased by adjustment of tower 
assembly 30 self-adjusting lifter blade will reposition itself by pivoting 
on hangers 38. 
Thus there has been disclosed an intermammary harvesting retractor that 
provides retractor adjustments allowing optimum access and visualization 
of the intermammary artery. The retractor is comprised of a fixed arm and 
a movable arm which has an adjustable lifter blade to lift the upper 
ribcage to view the intermammary artery. A support tower assembly on the 
free end of the retractor crossbar allows the tilt angle of the retractor 
to be adjusted to lift the upper ribcage to view the underside tissue 
providing improved access to the intermammary artery. The support tower 
has a support shaft whose length and position can be varied as necessary 
that cooperates with an adjustable lifter blade to lift and displace the 
upper portion of the ribcage to view the underside of the tissue 
containing the intermammary artery. In one embodiment an adjustable lifter 
blade is mounted on the movable arm. In a second embodiment a 
self-adjusting lifter blade is pivotally mounted on the movable arm. 
Obviously many modifications and variations of the invention are possible 
in light of the above teachings. It is therefore understood that the full 
scope of the invention is not limited to the details disclosed herein but 
only by the claims appended hereto and may be practiced otherwise as 
specifically described.