Basic Principles Of Local Flap In Plastic Surgery
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Transcript of Basic Principles Of Local Flap In Plastic Surgery
PRINCIPLES OF LOCAL FLAPS IN PLASTIC SURGERY
PRESENTED BY : DR. DEEPAK KRISHNA DR. SHAMENDRA ANAND SAHU DEPARTMENT OF BURNS , PLASTIC AND MAXILLOFACIAL
SURGERY VARDHAMAN MAHAVIR MEDICAL COLLEGE &
SAFDARJUNG HOSPITAL ,NEW DELHI
Definition :
A flap is a unit of tissue that is transferred from donor site to recipient site while maintaining its own blood supply.
Term “Flap” :
Originated from the 16th century Dutch word “FLAPPE” which means “anything that hung broad and loose, fastened only by one side”.
Timeline of the development of flap surgery
600 BC Sushruta Samhita Pedicle flaps in the face and forehead for nasal reconstruction 1597 Tagliacozzi Nasal reconstruction by tubed pedicle flap from arm; described
“delay” of pedicle flap 1896 Tansini Latissimus dorsi musculocutaneous flap for breast reconstruction (post- mastectomy) 1920 Gillies Tubed pedicle flap 1946 Stark1 Muscle flaps for osteomyelitis 1955 Owens Compound neck flap 1963 McGregor Temporalis flap 1965 Bakamjian Deltopectoral flap 1971 Ger11 Lower extremity musculocutaneous flap 1972 McGregor and JacksonGroin flap 1972 Orticochea1 Musculocutaneous flaps 1977 McCraw et al Musculocutaneous territories 1981Mathes and Nahai Classification of muscle flaps based on vascular anatomy 1981Ponten described fasciocutaneous flap
BASED ON LOCATION OF DONOR SITE
LOCAL FLAP: Flap transferred from an area adjacent to the defect.
DISTANT FLAP : Flap transferred from an
noncontiguous anatomic site.
CLASSIFICATION OF FLAP
LOCAL FLAP
BLOOD SUPPLY
METHOD OF MOVEMENT
COMPOSITION
LOCAL FLAPS
Local flaps can be classified based on their blood supply
Random flaps Axial flaps
• Based on the rich sub -dermal vascular plexus of the skin.
• Most of the local flap are random flaps.
• Maximum length : breadth ratio of 1 : 1 in the lower extremity.
• length : breadth ratio of up to 3 : 1 in the face.
• Derive their blood supply from a direct cutaneous artery or named blood vessel .
• Examples :Nasolabial flap (angular artery) , Forehead flap(supratrochlear artery).
• The surviving length of an axial pattern flap is entirely related to the length of the included artery.
Random flaps Axial flaps
CLASSIFIACATION OF LOCAL FLAP BASED
ON THE METHOD OF MOVEMENT
ADVANCEMENT FLAP PIVOT FLAP INTERPOLATION FLAP
CLASSIFICATION OF LOCAL FLAPS ON THE BASIS OF COMPOSITION
• Local flaps can also be categorized based on composition .
• The composition of the defect to be reconstructed should dictate the correct composition of the flap used for reconstruction.
• It includes : 1.Cutaneous 2.Fasciocutaneous 3.Musculocutaneous
HISTORY : CUTANEOUS CIRCULATION
Carl Manchot (1889 )
Performed the first examination of the vascular supply of the human integument.
Defined about 40 cutaneous territories on the basis of dissection of human integument.
His work “ Die Hautarterien des menschlichen Körpers “ [The Cutaneous Arteries of the Human Body], was initially published in German and later translated to English by Milton.
Spalteholz (1893)
Published paper on the origin, course and distribution of the cutaneous perforators in adult and neonatal cadavers.
He performed arterial injections of gelatin and various pigments. The soft tissues were fixed in alcohol and subtracted in xylol and the resulting vascular network was embedded in Canada Balsam.
Salmon (1930)
French anatomist and surgeon charted more than 80 cutaneous territories encompassing the entire body .
Salmon dissected 15 human cadavers and took radiographs of integument which enabled him to demonstrate much smaller vessel than Manchot.
Manchot 40 cutaneous territories Salmon 80 cutaneous territories
• The blood reaching the skin originates from deep vessels.
• DANIEL AND WILLIAMS(1973) defined that the deep vessels supplying skin are fundamentally two type of arteries i.e. either musculocutaneous or direct cutaneous arteries.
• Originally described as Direct cutaneous arteries , are now called as septocutaneous arteries.
• Both these type of vessels are present throughout the body but there exists appreciable difference between them which is tabulated as following :
Musculocutaneous arteries Septocutaneous arteries
Origin : Major vessel supplying muscle
Origin : segmental or muscular vessel
Travel perpendicularly through underlying muscle bellies into the overlying cutaneous circulation of the skin.
Arise originally from either segmental or musculocutaneous vessels, pass directly within intermuscular fascial septae to supply the overlying skin.
They are most prevalent in the supply of skin covering the broad, flat muscles of the torso.
This arrangement is most common between the longer, thinner muscles of the extremities.
Example : latissimus dorsi flap, rectus abdominis flap
Example : Radial forearm flap, Dorsalis pedis flap
WHY ?
DEEP FASCIA
TORSOWELL DEVELOPED DEEP FASCIA
COVERING THE BROAD MUSCLES WHICH IS ELASTIC PERMITING EXPANSION OF
ABDOMINAL MUSCLES .
LIMBSDEEP FASCIA IS MORE RIGID , NOT
ONLY COVERING THE MUSCLES BUT ALSO FORMS
INTERCOMPARTMENTAL FASCIAL SEPTA BETWEEN MUSCLES
PROVIDING ANCHORAGE TO THE VESSELS.
MUSCULOCUTANEOUS /SEPTOCUTANEOUS
ARTERIES
CUTANEOUS CIRCULATION
skin
subcutaneous fat
fascia
DIVIDED INTO 3 LEVELS
At the above said three anatomic levels 6 recognizable vascular plexus exists as shown in figure :
Fascial plexus : divided into1) Subfascial plexus : plexus lying on the under surface of the
fascia . relatively minor plexus . incapable of sustaining a fascial flap .
2) Prefascial plexus : dominant distribution system .
Subcutaneous Plexus• Network of vessels which divide subcutaneous fat
into deep (loose) and superficial (dense) layers.
• More developed in torso than in extremities.
• Supplied by both septocutaneous and musculocutaneous arteries.
Sub dermal Plexus :• Primary blood supply to the skin.
• Vessels have a continuous arterial muscular wall.
• Primarily distributor function.
• Located at junction between reticular dermis and subcutaneous fat.
• Corresponds with “dermal bleeding” at the edge of the flap.
• Arterioles run upwards to the overlying dermal plexus and others run downwards to supply adipose tissue and various glands .
Dermal Plexus• Present at lower limits of dermal papillary ridge.
• The Vessel in the plexus are arterioles and wall contains isolated muscular elements .
• Primarily thermoregulatory function.
Sub epidermal Plexus• Located at dermoepidermal junction.
• Consists mostly of capillaries having no muscle in their wall.
• Therefore they serve to have primarily nutritive function.
FLAP MODIFICATION
Modifications and refinements in both technique and design of flaps have been used for the optimal result in reconstructive surgery. Important modifications are :
1. Flap delay.2. Tissue expansion.
1. DELAY PHENOMENON
It can be defined as “ preliminary surgical intervention wherein a portion of the vascular supply to a flap is divided before definitive elevation and transfer of the flap”.
Delay procedure has been used for several hundred years.
16th century : Tagliacozzi delayed his upper arm flaps by making parallel incisions through the skin and subcutaneous tissue overlying the biceps muscle.
It was not until the early 1900s that the concept was recognized.
1921 :Blair introduced the term “DELAYED TRANSFER “ .
1965 : Milton using the pig model, investigated the effectiveness of four different methods of delaying a flap .
MECHANISM OF INCREASED BLOOD FLOW IN FLAP DELAY
1. Increased axiality of blood flow: Removal of blood flow from periphery of a random flap promotes development of axial flow. 2. Opening of choke vessels.
3. Tolerance to ischemia : adaptive metabolic changes at a cellular level within the tissue. 4.Sympathectomy vasodilation theory :
leading to vasodilation.
FLAP DELAY
Surgical flap delay is accomplished in two ways: 1.STANDARD DELAY : (A) with an incision at the periphery of the cutaneous territory. (B) partial flap elevation.
2. STRATEGIC DELAY :
involves division of selected pedicles to the flap to enhance perfusion through the remaining pedicle or pedicles .
2. TISSUE EXPANSION
1957 : Neumann is credited with the first modern report of this technique.
1976 : Radovan further described the use of this technique for breast reconstruction.
Advantages : 1. Reconstruction with tissue of a similar colour and texture to
that of the donor defect. 2. Reconstruction with sensate skin containing skin appendages.3. Limited donor-site deformity.
Planning and design of local flap
• Facial defects most common– Trauma– Skin malignancies
• Treatment– secondary healing– skin graft– local flaps
• History Peripheral vascular disease/Coronary artery disease Collagen vascular disease Diabetes mellitis Prior radiotherapy
Social habits cigarettes?• Medications ASA, anticoagulants• Cause of defect recurrence?
Physical Exam
• Defect size, placement • Surrounding skin lesions, laxity, color match, scars• Facial structures functional concerns, lip, lid• Incision placement Resting skin tension lines
Planning
• Template• Draw options/Measure• Planning in reverse• Incise• undermine• Rotate vs. advance vs. transpose• Key stitches• Close
Advancement Flaps
• First employed by Celsus in ancient Rome, popularized by French surgeons in the first half of 19th century
• Was called as “sliding flaps”
• Moves directly forwards into the defect without any lateral movement
Advancement Flaps
• Execution is facilitated by presence of excess skin
• More feasible in elderly or when skin elasticity is more like in very young
• Usually rectangular, perpendicular to the lines of minimal tension
• Uses – forehead , brow
Procedures devised to facilitate advancement• Excision of Burrow’s
triangle• Counterincision at the
flap base• Triangular design of the
flap• Curvilinear design of the
flap• Z-plasty at the base
Advancement Flaps
Burrow’s triangle at the base of the flap
V-Y Advancement flap Bilateral advancement flaps
V-Y Advancement Flap
Design• Advancement should be
directed over the shortest diameter of the defect• The size of the V base
should match the size of the largest diameter of the lesion • The V must be long enough
to allow tension-free suture of the Y
V-Y Advancement Flap•Advancement flap involves movement in two planes- vertical and horizontal•Pivot point on vertical plane which actually acts as a pivot plane•Pivot plane is the base of the flap at which the flap is attached to the body
V-Y Advancement Flap
• α angle is determined by– Location of defect – Elasticity of the surrounding tissues– Recommended to range between 20°-40°
• For leg defects, small angle is recommended as there is less elasticity
• Gluteal region- large angle is planned
Bipedicle Advancement Flap
Multiple Y-V advancement
W Plasty or Zigzag plasty
• Used to break up a single linear scar
• For scars that do not require lengthening
• It redistributes tension along the length of the scar
M-Plasty
• A useful technique to preserve healthy tissue in scar revision
• lessen the chance of standing cone (ie, dog-ear) deformity
• The M-plasty, by creating 2 separate 30° angles instead of one
Pivot Flaps
• Derives its name from the pivot point at the base
• The arc of rotation is under maximum tension• 2 types– Transposition flaps– Rotation flaps
Transposition Flap
• Usually rectangular or square flap• Transferred in a direction at right angles to
that of the blood supply• Additional length- Back Cut• Donor site
– Skin graft– Another flap
Transposition Flap- DESIGN
• Recipient defect is triangulated– Right angle triangle– Hypotenuse- near
border of the flap– The right angle
assumes a position opposite the flap
– In scalp defects, apex should direct towards the periphery of the scalp
• Pivot point D- across the base of the flap, parallel and equal to AB • From D, a line is drawn parallel to BC• With point D as axis, an arc is drawn from A and it intersects the line
at E• CB is extended to meet the arc at F• CFED is the marked flap• Flap transposed and donor area is grafted• In lower extremity length : breadth should be 1:1
Rhomboid flap described by Limberg in 1963
Dufourmentel Flap• Designed by a French
Surgeon, Claude Dufourmental in 1962
• The defect is tailored in the shape of a rhombus (with all sides equal)
• The short diagonal (BD) and one of the adjacent side (CD) are extended
Dufourmentel Flap
•Angle HDP is bisected•Line DE equals the side of the rhombus•EF is drawn parallel to AC and equal to side of the rhombus
Dufourmentel Flap
For square defect, both diagonals are equal, eight flaps can be designed
Bilateral Rhombic flap
Triple Rhombic flap
• Circular cutaneous defect conceptualized as hexagon.
• Sides of hexagon are equal to radius (r) of circle.
• First side of flap created by direct extension equal in
length to radius at alternative corners to prevent sharing
• of common sides.• Second side of flap designed
parallel to adjacent side of hexagon.
Bilobed Flap• Consists of two lobes of skin and subcutaneous tissue
based on a common pedicle• Design– Primary flap is smaller than the defect– Secondary flap is more triangular in shape• Optimal angle between the two flaps is 90°, can vary between
45° and 180°; greater the angle, larger the resultant dog-ear
• Zitelli's modification (1989), the primary flap is oriented 45° from the axis of the defect, and the secondary flap is oriented 90° from the axis of the defect; eliminate dog ears
• Convert the defect to a "tear drop" shape by the excision of a triangle on the side of pedicle base
• Use a caliper as a protractor, with one tip placed at the apex of the wound, to mark out two semicircles
• Outer semicircle defines the necessary length of the two lobes
• Inner semicircle bisects the center of the original wound and continues across the donor skin, defines the limit of the common pedicle of the two lobes
• Two lines are drawn from the apex of the wound– First line is placed 45° from the axis of the wound– Second line is placed 90° from the axis of the wound– These two lines mark the central axes of the two lobes of
the flap• Draw the flap with each lobe beginning and ending at the
inner semicircle and extending to the outer semicircle at the point where it crosses its central axis
Z Plasty
• Involves transposition of two interdigitating triangular flaps
• Effects– Gain in length along the direction of the common
limb of the Z– Direction of the common limb is changed
• Uses– Prevention and treatment of contracted scars– Scar revision
• In 1856, Denonvilliers first described the Z-plasty technique as a surgical treatment for lower lid ectropion.
• The first reference to this technique in American literature was in 1913, by McCurdy, as treatment for contracture at the oral commissure.
• Limberg, in 1929, provided a more detailed geometric description.
• Numerical data showing optimal angles and length relationships of Z-plasty limbs are credited to Davis (1946).
• Release of contracture– The central limb is placed along the line of
contracture- contractural diagonal– 60° angle taken on each side and limbs of Z drawn, all
equal in size– Longer diagonal is the transverse diagonal
•The contractural diagonal is under tension and springs up when flaps are raised•Causes change in shape of the parallelogram•Contractural diagonal lengthens
• Mechanism of lengthening by Z plasty– Length of contractural diagonal less than transverse
diagonal before release– Contractural diagonal lengthens at the expense of
transverse diagonal– Thus need for transverse skin laxity for contracture
lengthening– Variables in construction of Z Plasty• Angle size• Limb length
• Angle size– Length increases with in angle
ANGLE (°) INCREASE IN LENGTH (%)
30 25
45 50
60 75
• Angle size
– Increasing the angle beyond 60° will increase lengthening but also cause increased amount of transverse shortening
– Tension produced in the surrounding tissues tend to be so great that the flaps can not readily be brought in to their transposed position
• Limb length– With almost fixed angle, length provides the major
variable– Amount of tissue available determines the limb
length– More is the amount of tissue, larger the length
and vice versa
• Way of reducing the amount of transverse shortening without significantly reducing the amount of lengthening
• Also distributes the lateral tension over various limbs of multiple Zs
• In place of one large Z plasty, a series of multiple small Z-plasties are constructed
Multiple Z Plasty
Planning of Z-plasty for contracture release
• Narrow contractures with lax surrounding skin eg. Bowstring contracture
• Draw an equilateral triangle on each side of the contracture and select the more suitable of the two sets of limbs– Better blood supply; avoid a flap with scar at base– Resultant scar falling into a cosmetically
favourable line
• Flap of scarred skin should be designed a little longer initially than its fellow of the normal skin
• Two angles can be of unequal sizes also, lengthening will be equal to the average of the two angles
• Straight line scar– Break the continuity of a straight line scar, thus
rendering them more conspicuous • Bridle scar- scar crossing a hollow• Curving scar
Use in scar revision
Planning• Scar is outlined and the final postoperative
common limb (which preferably lies in a line of election) is drawn out
• The length of the intended common limb, which determines the size of the Z-plasty, is measured out on the line of the scar, proportioned approximately evenly on each side of the selected line and drawn out as the post-operative common limb
• From each end, a line of equal length is marked out to meet the line drawn out
• Thus Z-plasty flaps are outlined• This ensures that transposition of the flaps will
bring the common limb into the desired line as planned
• Unacceptable scar- lies >30° off the RSTLS– Z-plasty breaks the line of scar and changes its
direction
• Trapdoor scars• Significant subcutaneous scarring producing
contracture beneath the entire area of trapdoor
• Z-plasty lengthens the marginal scar and breaks up the subcutaneous scarring
Curving Scar
Four-Flap Z-plasty
The 5 – Flap plasty or “Jumping Man” flap.
Rotation –advancement Flap
• Semicircular flap which rotates around a pivot point
• Located along tension lines• Flap designed quite large than the defect to
ensure primary closure of the donor site• skin graft or another flap are alternatives for
the donor site
• Tissue can move into an adjacent defect in 2 directions.
• It can advance in a straight line (ie, advancement flap), or the tissue can rotate into the defect (ie, rotation flap).
• The distinction between the two is not always clear, and one type of motion blends into the other .
• Furthermore, a single flap can have both straight (advancement) movement and rotational (rotation) movement.
•Triangulation of the defect• Isoceles triangle• Apex towards flap
pedicle• Apex angle <30° to
avoid buckling of the skin
•PIVOT POINT D- on a projection of line AC, atleast CD>2AC•E is located midway between AD•An arc is drawn from B to D
•CBD constitutes the flap
Local flap template• ABC is the triangulated
defect• P is marked; AB=CP and
AB parallel to CP• P as center and AP as
radius, arc is drawn• Skin triangle ABD is
excised• CDE is the local flap
template for ABC
• Conventional rotation flap- geometrically pure rotation design where the triangulated defect is a sector of the semicircle
• Movement is diametrically opposite of the defect conflicting the fact that a skin flap rotated about a pivot point will become shorter in effective length the further it is rotated
• Hence conventional rotation flap are successful only in places where lax skin is present or a back cut is needed
• Flap template employs tissue just adjacent to the triangulated defect thus ensures coverage of the defect and closure of the donor site
Mustarde lateral rotation flap
Double rotation o-to-z
Postoperative Care
• Pain reliever• Wound care• antibiotic ointment• Sutures removed at 5-7 days• Revision if required - 6 months
Complications
• Infection• Dehiscence• Vascular insufficiency due to
• Mechanical tension• Kinking• compression
• Hematoma/seroma
• Failure/necrosis
FLAP NECROSIS
RANDOM PATTERN FLAP
Presents clinically as : congested , cyanosed ,blanching momentarily on pressure initially but with time becomes less and less until there is no circulation.
This process is acute .
settled one way or the other in 1-2 day, clearly defining area of necrosis.
FLAP NECROSIS
AXIAL PATTERN FLAP
The sequence is different with clinical events not fully understood .
Necrosis takes several days to develop.
Generally compromised flap is only slight cyanosed with no other gross signs .
The process is slow during which time the margin gets revascularised from surrounding tissues, due to which the area of final necrosis instead of being the entire distal flap , is an island in its centre.
• Length:Width increased width of base
would increase surviving length but feeding vessels have same perfusion pressure
• Perfusion pressure
PREVENTION OF FLAP NECROSIS
Important steps to prevent necrosis :
1.Avoiding tension by prior establishing pivot point or using planning in reverse if local flap is jumping over intact skin .
2. Planning the flap with a margin of reserve is an additional way in which tension can be avoided.
3.Avoding kinking particularly at the base of the flap.
4.In random flap proper length: breadth ratio should be maintained .
PREVENTION OF FLAP NECROSIS
5.In axial flap , length does not extend recognized safe length.
6.Proper plane for flap elevation for raising flap.
7. No compression at pedicle
8.Using delay principal when it was considered inadequate .
9.Avoiding infection : prevention of hematoma and avoidance of raw area .
PLANE FOR FLAP ELEVATION
Proper plane for flap elevation is of prime importance for preventing necrosis :
Trunk Between deep fascia and underlying muscle /aponeurosis
Limbs Immediately superficial or deep to investing layer of fascia .
Face At the level of fat just deep to dermis .
Scalp Between glea and pericranium.
Forehead Standard : superficial to pericranium.For smaller flap :between skin and frontalis muscle .
THINNING OF FLAP
Thinning of a flap is required for :1. To match the thickness of defect.2. To allow it to be set without tension.
The amount of thinning which flap tolerate safely varies greatly , such as :
Face Smaller flap can be thinned
out considerably due to well developed sub dermal plexus
Scalp Thinning not possible as flap is raised at subgleal level
THINNING OF FLAP
Limbs Thinning is seldom done because :
1.Fasciocutaneous flap : investing layer of fascia forming deep surface contains blood vessel crucial for survival.
2.Skin flaps : subcutaneous layer of fat is too thin to warrant thinning
Trunk Males : thinning is often not required in chest & upper abdomen.Female : Thinning is often required
What to Do if the Flap Becomes Swollen and BluishWithin Hours after the Operation
• A swollen, bluish flap indicates a problem with circulation into or out of the flap.
• Usually it is a venous (i.e., outflow) problem.• Make sure that the patient is positioned properly
and that nothing is compressing or pulling on the pedicle.
• Loosen surrounding dressings and tape. • Sometimes it is helpful to remove a few stitches to
ensure that the flap is not under too much tension.
• Be sure that no fluid has collected under the flap.
• Any collection of fluid requires drainage.
• Ensure adequate pain control. Pain stimulates the sympathetic nervous system, which decreases blood flow through the pedicle.
What to Do If Part of the Flap Dies
• If a part of the flap has become purplish• it indicates inadequate circulation• the tissue may eventually die.• If there is no evidence of infection, you may simply
leave the flap alone.• With time, this tissue will demarcate and die and
then separate or you may have to cut off the dead tissue.
• While this process is occurring, the underlying tissues will heal.
THANK YOU