Muscle Flaps - Medical Student LC
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Transcript 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
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
Oscillating veins
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
Balance reconstructive needs and sacrifice of
normal function
Reconstructive Ladder versus Triangle
Defect analysis
Location
Size
Physical Components
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)
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
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
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
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
Intercostal
Orbicularis oris
Examples – Type IV
Segmental Pedicles
Sartorius
Tibialis Anterior
External Oblique
Extensor Hallucis Longus
Flexor digitorum longus
Flexor hallucis longus
Examples – Type V
Single Dominant and
secondary segmental
pedicles.
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
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
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
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
Innervation
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
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.
Origin – Pubic symphysis
Insertion – Medial Tibial condyle
Gracilis – Type II
Innervation
Motor – anterior branch of obturator
Sensory – anterior femoral cutaneous (L2-3).
Function – thigh adductor.
Gracilis – Type II
Vascular Anatomy
Dominant
Ascending branch of medial circumflex femoral.
Length – 6 cm, Diameter – 1.6 mm.
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.
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
Special case
Functional muscle transplant
Mark muscle resting length with sutures prior to
disinsertion
Dissect out obturator nerve
Vaginal reconstruction – paired flaps
Trapezius – Type II
Trapezius – Type II
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
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
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
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
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.
Soleus – Type II
Soleus – Type II
Applications – coverage of middle third +/- lower
third of leg
Location
Origin
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
Innervation
Motor – posterior tibial and medial popliteal nerves
Function- plantar flexion of the foot
Soleus – Type II
Vascular Anatomy
Dominant
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
Arc of rotation
Standard – middle third of tibia
Distal – distal third of tibia, based on minor
pedicles. (Distal hemisoleus, more reliable)
Soleus – Type II
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
Standard Flap
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.
Gluteus Maximus – Type III
Gluteus Maximus – Type III
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
Vascular Anatomy
Dominant
Superior gluteal artery (Length 3 cm, diameter 2.5 mm)
Inferior Gluteal artery (Length 3 cm, diameter 2.5 mm)
Minor
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)
Function
Extends and laterally rotates the thigh
Gluteus Maximus – Type III
Arc of Rotation
Standard
Axis edge of sacrum
Covers sacrum and ipsilateral ischium
Reverse (Inferior half)
Divide origin and inferior pedicle
To posterior lateral thigh
Segmental transposition
Gluteus Maximus – Type III
Elevation
Easily identified
Standard flap
Superior half –cover sacrum
Inferior half – cover ischium
Gluteus Maximus – Type III
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
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
Function
Flexes vertebral column, tenses abdominal wall.
Rectus Abdominus – Type III
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
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
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
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.