Download Muscle Flaps - Medical Student LC

Muscle Flaps
Trefor Nodwell MD CM
Dr. D. Lalonde, FRCSC
Dr. W. Parkhill, FRCSC
Outline

Review
Basic Anatomical and Physiologic Review
 Reconstructive Goals & Principles
 Classification Schemes with examples
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
Muscle Flaps Only

Common Examples
Type/Pattern of Circulation
 Applications
 Anatomy and Elevation

Outline

Precautions/Pitfalls

Brief overview of Less Common (but
applicable) flaps

Discussion
The Basics - Anatomy


Motor nerves are always accompanied by
vascular pedicles
Pedicles
Dominant – can sustain entire muscle on its own
 Minor – maintains only a portion of the muscle
 Segmental –nourishes small segment of the muscle


Allows for a classification scheme
The Basics- Physiology

Arc of Rotation
Standard – extent of reach of the muscle based on
its dominant pedicle
 Reverse (distally based) – restricted by secondary
pedicles

The Basics- Physiology

Choke arteries

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Oscillating veins

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Small caliber vessels allowing bidirectional flow
No valves, allows reversal of flow
Perforators
Vessels pass through muscle to supply overlying skin
 Identified preoperatively

The Basics


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Balance reconstructive needs and sacrifice of
normal function
Reconstructive Ladder versus Triangle
Defect analysis
Location
 Size
 Physical Components

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Environment –host factors
The basics – Goals & Principles

Safety - successful wound coverage
Identify and protect pedicle
 Conservative skin territories
 Tension- at pedicle or inset site


Form- normal shape or contour
Restoration at defect
 Preservation at donor site

The basics – Goals & Principles

Function – stability of closure, specialized
functions.
Hair growth
 Sensibility
 Skeletal Support
 Locomotion (or animation)

Classification
Classification

According to mode of innervation (Taylor)
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Type I – single unbranched nerve enters muscle.
Type II- Single nerve, branches prior to entering.
Type III – Multiple branches from same nerve trunk.
Type IV – Multiple branches from different nerve trunks.
Affects suitability for functioning muscle transfer
Classification
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Vascular Supply (Mathes and Nahai, PRS, 1981)
Type I – Single vascular pedicle
Type II – Dominant pedicle, minor pedicle(s)
Type III – Dual dominant pedicles
Type IV – Segmental Pedicles
Type V – Dominant pedicle with secondary segmental pedicles
Examples – Type I

Single Vascular Pedicle

Tensor fascia Lata
Gastrocnemius
Genioglossus
Stylogossus
Anconeus
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First Dorsal Interosseus
Abductor Digiti Minimi
(hand)
Abductor Pollicis Brevis
Vastus Lateralis
Examples – Type II

Dominant Vascular
Pedicle and Minor
Pedicles

Gracilis
Trapezius
Soleus
Rectus femoris
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Coracobrachialis
Biceps Femoris
Triceps
SCM
Platysma
Brachioradialis
Abductor digiti minimi
(foot)
Examples – Type III

Two Dominant Pedicles

Gluteus Maximus
Rectus abdominus
Serratus
Temporalis
Pectoralis Minor

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Intercostal
Orbicularis oris
Examples – Type IV
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Segmental Pedicles
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Sartorius
Tibialis Anterior
External Oblique
Extensor Hallucis Longus
Flexor digitorum longus
Flexor hallucis longus
Examples – Type V

Single Dominant and
secondary segmental
pedicles.
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Latissimus Dorsi
Fibula
Pectoralis Major
Internal oblique
Common Examples

Each reviewed in terms of
Applications
 Features – Location, size, origin, insertion
 Classification
 Nerve supply – motor and sensory
 Function
 Anatomy – vascular
 Arc of rotation
 Elevation

Tensor Fascia Lata
Tensor Fascia Lata - Type I

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Applications- Coverage of lower abdominal
wall, perineum, ischium and sacrum. Free flap.
Small thin, flat. 5X15cm.
Origin – ASIS and crest. Behind sartorius
Insertion – Iliotibial tract of Fascia Lata.
Innervation
Superior Gluteal
 T12 and lateral femoral cutaneous

Tensor Fascia Lata - Type I


Function - flexes and abducts the thigh
Vascular Anatomy
Ascending branch lateral circumflex femoral (off
Profunda femoris)
 Pedicle: length – 7cm, Diameter 2-3mm


Arc of Rotation
Anterior – abdominal wall, groin, perineum
 Posterior – greater trochanter, ischium, perineum,
sacrum.

Tensor Fascia Lata - Type I


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Musculocutaneous
V-Y advancement
Fasciocutaneous
Precautions
Distal end less reliable (consider delay)
 Donor site closure – possible thigh compartment
syndrome
 Donor site often requires grafting

Gastrocnemius - Type I
Gastrocnemius - Type I
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
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Applications – coverage of inferior thigh, knee,
contralateral leg.
Location – superficial posterior calf. Medial and
lateral heads. 20X 8 cm.
Origins – medial and lateral femoral condyles
Insertion – calcaneus via Achilles tendon
Gastrocnemius - Type I

Pedicles
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Innervation
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Major - Medial and
Lateral sural arteries
Minor – paired
anastomotic sural vessels\
Tibial nerve
Saphenous (medial), Sural
(lateral)
Function – plantar
flexion of the foot.
Gastrocnemius - Type I


Vascular Anatomy - medial and lateral muscles
Arc of rotation - Medial
Standard - suprapatellar thigh, knee, upper 1/3 tibia.
 Extended – by 5-8cm
 Distally based – middle third of leg.
 V- Y advancement to Achilles

Gastrocnemius - Type I

Skin territories – Vertical and transverse islands.


10 X 23 cm
Elevation
Supine or lateral decubitus position.
 Stocking seam incision
 Pedicles in popliteal fossa entering deep surface, near
origins superior to popliteal crease
 Popliteal vein and tibial nerve – superficial to
popliteal artery

Gastrocnemius - Type I

Precautions
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Preserve soleus
Tourniquet recommended – avoid nerve injury
Standard flap leaves better scar
Preoperative angiography
Relative contraindication – recent DVT
Gracilis – Type II
Gracilis – Type II


Applications – groin, perineum, abdomen,
ischium. Vaginal reconstruction. Facial
reanimation.
Location – medial thigh. Pubis to medial knee
Thin, flat 6X24 cm.
 Adductor longus and sartorius anteriorly
 Semimembranosus posteriorly.
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Origin – Pubic symphysis
Insertion – Medial Tibial condyle
Gracilis – Type II

Innervation
Motor – anterior branch of obturator
 Sensory – anterior femoral cutaneous (L2-3).
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Function – thigh adductor.
Gracilis – Type II
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Vascular Anatomy
Dominant
Ascending branch of medial circumflex femoral.
 Length – 6 cm, Diameter – 1.6 mm.

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Minor
one or two branches of superficial femoral
 Length – 2 cm, Diameter – 0.5 mm

Gracilis – Type II

Arc of Rotation
Standard – groin perineum vagina, anus and ischium
 Distal – requires delay, arc to knee.


Skin territory
Pubis to junction of middle and lower third between
rectus anteriorly and biceps posteriorly.
 16X18cm

Gracilis – Type II

Flap Elevation
Draw line from Symphysis to medial femoral
condyle – cut 3cm posterior to this.
 Pedicle location – 10cm inferior to pubic tubercle.
Retract the adductor longus to expose.
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Muscle
superficial to adductor magnus
 Medial to adductor longus
 Anterior to semimembranosus

Gracilis – Type II

Precautions
Selective arteriography if prior vascular surgery
 Confirm skin island position often

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Special case
Functional muscle transplant
Mark muscle resting length with sutures prior to
disinsertion
 Dissect out obturator nerve
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Vaginal reconstruction – paired flaps
Trapezius – Type II
Trapezius – Type II
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Applications – Skull, head and neck, Oral cavity,
posterior trunk and shoulder. Mandible facial
reanimation.
Location – large, flat, triangular. Superficial. 34 X 18 cm
Origin – external occipital protuberance, medial third
of sup. nuchal line, ligamentum nuchae, spinous
processes of C7 to T12
Insertion – lateral third of clavicle, spine of scapula,
acromion.
Trapezius – Type II
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
Vascular anatomy
Dominant
Transverse cervical artery
 Length 4 cm, diameter 1.8 mm


Minor
Branch of Occipital artery
 Length 3 cm, diameter 1mm
 Dorsal Scapular artery
 Length 4 cm, diameter 1.6mm.

Trapezius – Type II

Innervation
Motor – CN XI (spinal accessory)
 Sensory - #rd and 4th cervical nerves, intercostals

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Function

Rotates scapula, elevates shoulder during abduction
and flexion of arms
Trapezius – Type II

Arc of Rotation
Standard – Posterior skull, cervical and thoracic
vertebral column, midface and neck.
 Reverse – midline of trunk

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Skin territory

20 X 8 cm.
Trapezius – Type II

Elevation
Mark midline, scapular border, midportion of
scapula. Midpoint between scapular tip and PSIS
 Position prone or lateral decubitus
 Pedicle –

Vertical flap - vertical component TCA. Deep surface of
middle fibers, over superior rhomboid
 Lateral flap – ascending branch of TCA identified in
posterior neck

Trapezius – Type II
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Vertical Flap
Trapezius – Type II

Precautions
Preserve superior fibers
 Selective ateriography if radiated or radical neck
dissection.
 Use Doppler to identify segmental vessels in reverse
flap
 Shoulder immobilization post op to avoid tension on
closure.
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Soleus – Type II
Soleus – Type II
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Applications – coverage of middle third +/- lower
third of leg
Location
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Origin
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large, broad, bipennate, deep to gastroc. Medial and lateral
bellies. Fused proximally.
8X28 cm (Flap dimensions 7-12 cm)
Lateral posterior head and body of fibula
Medial middle third of medial border of tibia
Insertion

Calcaneus via Achilles tendon
Soleus – Type II
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Innervation
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Motor – posterior tibial and medial popliteal nerves
Function- plantar flexion of the foot
Soleus – Type II
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Vascular Anatomy
Dominant
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Proximal two branches of popliteal artery (Length 0.5-1 cm,
diameter 1-1.5mm)
Proximal two branches of posterior tibial artery (Length 1-2
cm, diameter 1-2 mm) medial belly
Proximal two branches of peroneal artery (Length 1-2 cm,
diameter 1-2 mm) lateral belly
Minor

3-4 segmental branches of posterior tibial (L 1-1.5 cm, D 0.5
1mm)
Soleus – Type II
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Arc of rotation
Standard – middle third of tibia
Distal – distal third of tibia, based on minor
pedicles. (Distal hemisoleus, more reliable)
Soleus – Type II
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
Elevation
Landmarks – medial border of tibia, fibula
laterally. Extends below gastrocs and plantaris.
Pedicle
Deep surface (Post tib medial, peroneal laterally)
 Minor segmentals – distal medial border

Soleus – Type II
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Standard Flap
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Medial incision, transposed laterally.
Lateral approach
Hemisoleus – medial and lateral.
Pedicle length cannot be extended
Soleus – Type II

Precautions
Congenital adhesions
 Distally based lateral hemisoleus has less reach than
medial.
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Gluteus Maximus – Type III
Gluteus Maximus – Type III
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Applications – Sacrum , Ischium, Trochanter,
breast reconstruction.
Location – large, quadrilateral, most superficial.
24X24 cm
Origin – gluteal line of ilium and sacrum
Insertion – Greater tuberosity of femur,
iliotibial band.
Gluteus Maximus – Type III
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Vascular Anatomy
Dominant
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Superior gluteal artery (Length 3 cm, diameter 2.5 mm)
Inferior Gluteal artery (Length 3 cm, diameter 2.5 mm)
Minor

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First perforator of Profunda femoris (L 5 cm, D 1.5mm)
Intermuscular branches of lateral circumflex femoral (length
1 cm, diameter, 0,6 mm)
Gluteus Maximus – Type III

Innervation
Motor – inferior gluteal nerve (L5 to S1-2) via sciatic
foramen at level of piriformis
 Sensory – Posterior divisions of L1-3 laterally, S1-3
medially)

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Function
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Extends and laterally rotates the thigh
Gluteus Maximus – Type III
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Arc of Rotation
Standard
Axis edge of sacrum
 Covers sacrum and ipsilateral ischium
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Reverse (Inferior half)
Divide origin and inferior pedicle
 To posterior lateral thigh
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Segmental transposition
Gluteus Maximus – Type III
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Elevation
Easily identified
Standard flap
Superior half –cover sacrum
Inferior half – cover ischium
Gluteus Maximus – Type III
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Donor closure


Recommended, V-Y advancement may facilitate this.
Precautions
Not expendable
 Denervation atrophy
 Piriformis – key to division of midportion
 Sciatic nerve – inferior flap

Rectus Abdominus – Type III
Rectus Abdominus – Type III
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Applications – Thorax, abdomen, perineum,
Breast, head and neck upper and lower
extremities.
Location –vertical, costal margin to pubis, long
flat, three tendinous intersections.. Length 25X6
cm.
Origin – crest of pubis, symphysis
Insertion – 5th to 7th ribs
Rectus Abdominus – Type III

Innervation
Motor – segmental 7th to 12th intercostal nerves
 Sensory – 7th to 12th intercostal nerves

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Function

Flexes vertebral column, tenses abdominal wall.
Rectus Abdominus – Type III
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
Vascular anatomy
Dominant
Superior epigastric (L 2cm, D 1.8 mm)
 Inferior epigastric (L 5 cm, D 2.5 mm)


Minor

Subcostal and 6-7 intercostal arteries
Rectus Abdominus – Type III
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
Arc of rotation
Standard – two
Superior epigastric – Anterior thorax
 Inferior epigastric – Groin Perineum and inferior
trunk


Skin territory
Vertical standard or island
 Transverse ipsilateral or TRAM

Rectus Abdominus – Type III


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Elevation
Landmarks – costal margins to pubic ramus
Easily palpable
Leg raising maneuver
Standard muscle flap – numerous modifications
Donor closure
Critical to prevent herniation
 Avoid tension on pedicle base

Rectus Abdominus – Type III

Precautions
Previous abdominal surgery - Kocher, Pfannenstiel
 Prior LIMA/RIMA surgery
 Segmental flap elevation may not preserve function
 Marlex mesh reinforcement
 Direct donor site closure preferred.

Serratus Anterior –Type III
Serratus Anterior –Type III




Applications – head and neck, Thorax, axilla,
posterior trunk, breast reconstruction and free
tissue transfer
Thin, broad, multidigitated. 15X20cm.
Origin – outer surface upper nine ribs
Insertion – ventral surface of medial border of
scapula.
Serratus Anterior –Type III

Innervation
Motor – Long thoracic N. (C5-7 roots)
 Sensory – T2-4 segmental intercostals


Function – pulls medial border of scapula
anteriorly. Prevents winging.
Serratus Anterior –Type III


Vascular anatomy
Dominant
Lateral thoracic (L 6-8 cm, D 2-2.5 mm)
 Branches of Thoracodorsal (L 6-8 cm, D 2-2.5 mm)
– enters posterior to Lat. Thoracic.

Serratus Anterior –Type III




Arc of rotation
Standard - chest wall, shoulder, axilla, back.
Extended – divide one of the two pedicles.
Combined Serratus-Latissimus dorsi flap.
Serratus Anterior –Type III


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Elevation - Standard
Mark Lat. dorsi and Pec. major
Scapular tip
Elevate skin flaps anteriorly and posteriorly
Pedicles
Lateral Thoracic – upper 3-5 slips, deep to pec
 Thoracodorsal – 6 cm lateral and below LT pedicle

Serratus Anterior –Type III


Identify lower 3-4 slips (on TD pedicle)
Identify Nerves
Lateral thoracic – superficially, at 6th rib with TD
pedicle
 Long Thoracic



Divide vessels to latissimus.
Donor site closed primarily.
Serratus Anterior –Type III

Precautions
Identify thoracodorsal pedicle early to speed
dissection
 Prevent winging – 3-4 segments, prevent
denervation.
 Tunneling – potential for vascular compromise.

Latissimus Dorsi – Type V
Latissimus Dorsi – Type V




Applications – among the most varied
Location – large flat, triangular, postero-inferior
trunk. Deep to trapezius. 25X35cm.
Origin – aponeurosis to thoraco lumbar fascia,
T7-12 spinous processes, sacrum, post iliac crest
Insertion – scapular tip. Intertubercular groove
of humerous.
Latissimus Dorsi – Type V


Vascular anatomy
Dominant


Thoraco dorsal artery (L 8 cm, D 2.5mm)
Secondary Segmental
Lateral Row (L2-3cm, D 2.5 mm)
 Medial Row (L 1-2 cm, D 0.5 mm)

Latissimus Dorsi – Type V

Innervation
Motor – Thoracodorsal (C6-8) – enters with
dominant pedicle
 Sensory – Lateral intercostal cutaneous nerves
(divided)


Function – adducts, extends and rotates the
humorous
Latissimus Dorsi – Type V


Arc of Rotation
Standard
Axis at posterior axilla
 Posterior – neck, occiput, parietal skull.
 Anterior – hemi thorax, sternum, mid face, upper
abdomen.


Extended


5-10 cm more
Reverse – off segmentals
Latissimus Dorsi – Type V






Elevation -Standard muscle flap
Posterior axillary incision 5-10cm
Pedicle – in posterior axilla deep to muscle. 1015 cm below insertion.
Proceed from inferior/medial to superior/lateral
Divide insertion only after pedicle is isolated
Donor site closure – direct 5-7cm.
Latissimus Dorsi – Type V

Precautions
Relative contraindication contra-lateral shoulder
girdle is paralyzed
 Denervated muscle is difficult to dissect
 Do not divide branch to serratus until subscapularthoracodorsal system is identified.
 Adhesions with serratus
 Identify segmental vessels prior to reverse
transposition.

Pectoralis Major – Type V
Pectoralis Major – Type V




Applications Coverage, Reconstruction,
Functional transfer, Free flap.
Location – flat, fan shaped. 15X23 cm.
Origin – Medial clavicle, anterior sternum, upper
seven costal cartilages, ext. oblique aponeurosis.
Insertion – Lateral lip of bicipital groove.
Pectoralis Major – Type V


Vascular Anatomy
Dominant


Minor


Pectoral branch of Thoracoacromial artery (L 4cm. D 2-2.5
mm)
Pectoral branch of lateral thoracic (L 3-4 cm, D 1-2 mm)
Minor Segmental


Internal mammary perforators (L 1-2 cm, D 1-2mm)
Intercostal perforators, 5-7th (L 1-2 cm, D <0.5mm)
Pectoralis Major – Type V


Innervation
Motor
Lateral (Superior) Pectoral nerve – deep surface near
dominant pedicle.
 Medial (Inferior) Pectoral nerve – via pec minor to
posterolateral pec major.


Sensory


2-7th intercostal nerves
Function – arm adduction and medial rotation.
Pectoralis Major – Type V


Arc of rotation
Standard


Extended


Head and neck, sternal defects
3-5 cm – Inferior orbital rim, intrathoracic cavity
Reverse (turn over)

Sternum and mediastinum
Pectoralis Major – Type V

Elevation


Standard (Thoraco acromial pedicle)
Midline incision – elevate skin flaps then muscle
Identify pedicle – deep surface, junction of middle
and lateral thirds of clavicle.
 Minor pedicles cauterized.


Incise origin – island muscle flap
Pectoralis Major – Type V

Precautions
Less reliable as vascularized bone flap (5th-6th rib)
 Bulky in head and neck reconstruction
 Donor deformity (loss of axillary fold) – minimized
with segmental transpositions.
