Reconstruction Principles and flaps

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Head and Neck Reconstruction
Broad aims
1) ablative cure
2) restoration of function;
3) reconstruction of form.
Multidisciplinary team
 head and neck surgeon
 plastic surgeon
 radiation oncologist
 medical oncologist
 maxillofacial prosthodontist,
 dentist
 radiologist
 pathologist,
 speech and occupational therapists
 dietician
 psychologist, and social worker.
functional objectives in oropharyngeal reconstruction are to
 restore sensation
 maintain oral continence
 facilitate swallowing (deglutition)
o requires a structurally sound upper digestive tract to move the food bolus
from the mouth to the stomach.
o Ensure tongue mobility – not tethered
o Avoid redundant pouches
o Restore dentition
 prevent aspiration
 preserve speech
 protect vital structures
 achieve primary wound healing
 obtain cosmesis
SSG
 used in defects of the maxillary area, alveolar ridge, anterior buccal mucosa,
dorsal surface of the tongue, and posterior esophageal wall.
 Does not mucosalise
Local random flaps
Tongue flap
 posteriorly based pedicled tongue flap
 blood supply of the flap is via the lingual artery, which enters the undersurface of
the tongue near its posterior aspect.
 As much as 20% to 40% of the lateral tongue is usually elevated
 base of the tongue and floor of the mouth are not violated, and the donor defect is
closed primarily without impairment of speech or swallowing.
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particular benefit in lesions of the tongue,
tonsillar region, retromolar trigone, and palate.
bring pliable, well-vascularized local tissue and
do not restrict mandibular excursion
venous drainage, in order of decreasing
diameter of the vein and size of its drainage
area:
1. accompanying vein of the hypoglossal nerve
2. epiglottic valleculate vein
3. accompanying vein of the lingual nerve
4. lingual root vein
5. accompanying vein of the lingual artery.
Nasolabial flap
 extends from approximately 5 mm below the medial canthus to the level of the
oral commissure and is tunneled through the cheek mucosa to resurface the
excisional defect
Axial Flaps
1. Forehead (Temporal) Flap
2. Superficial Temporal Artery Fascial Flap
3. Temporalis Muscle Flap
4. Deltopectoral Flap
5. Facial Artery Musculomucosal Flap
6. Buccinator Flap
7. Submental Flap
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Although technically easy and clinically reliable, axial flaps often suffer from
extensive donor site deformity.
The transfer of axial flaps is usually accomplished in two operative stages, which
frequently results in salivary fistulas until the flap pedicle can be divided
Forehead flap
 one-half to two-thirds of the forehead
 based on the superficial temporal vessels.
 folded and tunneled through the cheek to enter the oral cavity just below the level
of the zygomatic arch; at a second stage the pedicle was divided and returned to
the forehead.
 folded and tunneled
 through the cheek to enter the oral cavity just below the level of the zygomatic
arch; at a second stage the pedicle was divided and returned to the forehead.
 Careful beveling of incisions at the brow and hairline to minimize donor site
morbidity.
 The reach and length of the flap are thus increased, but a delay procedure is
mandatory.
 5% to 15% incidence of distal tip necrosis.
 To minimize the donor site defect, integra + SGG camy be used for the donor site
Temporalis flap
 TPF flap can be used to cover the parotid bed
 Temporalis muscle may be used for soft tissue fill
 Zygomatic arch may need to be temporarily removed
so that it can comfortably reach the tonsillar fossa or
posterior floor of the mouth.
Deltopectoral flap
 Bakamjian states the externally transferred flap will
reach the orbit and zygoma and the nasopharynx
internally.
 3 sources of blood supply
1. first four perforating branches of IMA (mainly 2nd
and 3rd)
2. upper midportion – thoracoacromial axis
3. deltoid perforators
 flap may be transferred without a delay procedure so long as the skin paddle in the
deltoid portion distal to the cephalic groove does not exceed a 1:1 length:width
ratio.
 15% major flap loss and 15% minor flap loss rates
 In defects of the palate and above, expect 40% to 50% complication rates
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angiosome concept provides a framework for describing delay procedures that are
used to increase the reliability of the deltoid skin.
o To capture the blood supply of that territory, it is important to reverse the
direction of blood flow in the adjacent thoracoacromial angiosome and the
third angiosome in line overlying the deltoid region.
o The delay procedure must interrupt the direct cutaneous branch of the
thoracoacromial trunk and the more distal musculocutaneous branches of
the deltoid muscle.
o This is accomplished by raising the tip of the flap lateral to the D of the
deltopectoral groove
Facial artery musculomucosal (FAMM) flap (Pribaz 1992)
 Contains mucosa, submucosa, buccinator muscle, buccal fat, and facial artery
(flap is 8-10mm thick)
 can be based either superiorly or inferiorly
o superiorly based- may be used for defects of the hard palate, alveolus,
maxillary antrum, nose, upper lip, and orbit.
o inferiorly based - used for defects of the hard and soft palate, tonsillar
fossa, alveolus, floor of the mouth, and lower lip.
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width of the flap averages 1.5 to 2 cm and is well anterior to Stenson's duct
rich venous drainage occurs by means of a plexus draining posteriorly to the
pterygoid plexus and internal maxillary vein and anteriorly to the facial vein
facial vein cannot be reliably included in the flap pedicle as it is often separated
from the artery at this level
buccinators has dual; blood supply from buccal artery (from maxillary) and facial
artery
Course of facial artery in face
o enters the face by hooking around the lower border of the mandible at the
anterior edge of the masseter muscle
o lies deep to the risorius, zygomaticus major muscle, and superficial lamina
of the orbicularis oris muscle.
o lies superficial to the buccinator, the levator anguli oris muscle, and the
lateral edge of the deep lamina of the orbicularis oris muscle, and it has a
variable relationship to the levator labii superioris muscle (artery usually
deep)
Usually marked by Doppler intraoperatively
Axis: from the retromolar trigone to the level of the labial sulcus (ipsilateral) near
the alar margin.
Buccinator Musculomucosal Flap (Bozola 1989)
 supplies the posterior half of the muscle and is the principal arterial pedicle to the
buccinator.
 blood supply and orientation of the pedicle of the buccinator flap are different
from those of the FAMM flap
posterior buccal branch (Pb), inferior buccal branches (Ib), and anterior buccal
branches (Ab) of the facial artery (Fa). Anastomotic network (An) between all these
branches to the buccinator is located below the parotid duct
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mean dimensions are 3.5 cm width and 7 cm length.
5 to 8 mm inferior to the parotid opening is set as the upper margin of the flap
Axis - 1.0 cm anterior to the pterygomandibular raphe in an anterior direction to
the buccal commissure
primarily indicated for reconstruction of the anterior and lateral floor of the
mouth.
To ensure reliability of the flap, the facial artery should be preserved during neck
dissection and the ipsilateral molar teeth must be extracted. Bite block often
required
Diagrammatic representation of the Buccal and FAMM flaps. The Buccal flap
is supplied by the buccal artery (Ba) of the internal maxillary artery and the
posterior buccal branch (Pb) of the facial artery. The FAMM flap is supplied
by the distal portion of the facial artery (Fa) through the anterior buccal
branches (Ab) of the facial artery.
Submental artery flap(Martin PRS 1993)
 Large skin paddles (up to 7 x 18 cm) can be raised to cover the ipsilateral
oral cavity and face while hiding the scar under the mandible.
 Branch arises after the facial artery exits from the submandibular gland. It
runs on top of the mylohyoid muscle below the mandible.
 In 70%, the submental artery passes deep to the anterior belly digastric
muscle. Ipsilateral muscle should be raised with the flap, especially for
flaps extending beyond the midline (Martin et al. raised the flap without
inclusion of the anterior belly of the digastric muscle with no flap failure.)
 usually two major perforators, with one coming off proximal to the
digastric muscle and the other distal. Minor perforators come directly
through the anterior belly of the digastric
 can be dissected to the facial artery and can be based superiorly or
inferiorly, thereby extending the length of the pedicle and hence the reach
of this flap
 facial vein provides venous drainage.
 upper incision of the flap (1.5cm below the mandible) should be made first
with identification and careful preservation of the mandibular branch of
the facial nerve.
 Subplastysmal dissection
 Advantages:
o Makes use of redundancy in older patients
o Hair bearing skin ideal for beard reconstruction
 Less ideal for nasal reconstruction than forehead flap
o Poorer donor site
o thicker than the forehead flap, and the geometry of a pedicled
submental flap makes it much more difficult to fold and shape to
adequately reconstruct the lower part of the nose, nostrils, and
columella.
MUSCULOCUTANEOUS FLAPS
1. Pectoralis Major Flap
2. Latissimus Dorsi Flap
3. Sternocleidomastoid Flap
4. Platysma Flap
5. Infrahyoid Flap
6. Trapezius Flap
7. Serratus Anterior Flap
Neck flaps have disadvantage of
1. potential involvement with metastatic spread of tumor
2. risk of circulatory interruption by the excisional surgery
3. damage inflicted by any preoperative irradiation
Pectoralis Major flap
 Type V
 Major pedicle = thoracoacromium
 Minor = medial rows of IMA perforators (1-6)
 Minor = more lateral row of perforators from anterior intercostals
 Sternal head origin
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1. manubrium
2. body of sternum
3. aponeurosis of external oblique over the attachment of rectus abdominis
4. upper 6 costal cartilages
Clavicular head origin
1. medial half of anterior surface of clavicle
Insertion: lateral lip of bicipital groove
Action
1. adduction (sternocostal head)
2. internal rotation
3. flexion (clavicular head)
Nerve supply
 medial pectoral nerves (C7,8,T1) – sternal head
 lateral pectoral nerves (C5,6) – clavicular head
pectoral branch of the thoracoacromial artery – exits the subclavian artery at the
midportion of the clavicle – courses medial to the insertion of the pectoralis
minor tendon.
Axis – perpendicular line from midine of clavicle to intersect line from acromium
to xiphisternum
Disadvantages:
1. the donor site defect is disfiguring, particularly in women
2. the skin paddle is sometimes hair-bearing in men
3. the paddle is excessively bulky, especially in certain patients who require
tubing of the skin to reconstruct the pharyngoesophagus or in whom
oropharyngeal reconstruction may interfere with tongue function
4. the arc of flap rotation is limited
5. the muscle pedicle bulges in the neck
6. shoulder dysfunction is not uncommon
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Modifications in women
1. Ariyan recommend placing the skin under the breast to benefit from the
network of vessels in the fascial extensions from the muscle
2. Sharzer prefer a vertically oriented parasternal paddle that incorporates
the skin medial to the nipple as far as the opposite internal mammary
perforators. During transfer only the sternocostal muscle is divided. Breast
distortion is said to be minimal
Modifications to reduce bulk of skin component
1. Some have left muscle surface raw in oral cavity - noting that within 1
month it was covered with squamous epithelium. The flap remained
healthy and reepithelialized even in the face of radiotherapy. May risk
contracture
2. vertically oriented parasternal skin paddle (thinner)
3. skin graft (prelaminated described)
Modifications to increase arc of rotation
1. place the skin paddle lower
2. divide medial half of the clavicle, adds 2.5–3 cm in length to the flap.
Modifications to reduce muscle bulk in neck
1. transect the medial and lateral pectoral nerves;
2. exteriorize the muscle and later resect it after the skin paddle has
revascularized
Modifications to reduce shoulder dysfunction
1. raise sternocostal portion only – preserve clavicular portion and the medial
pectoral nerve (lies medial to thoracoacromial axis)
Can be raised with 5th rib
o problem is that the pectoralis major muscle inserts onto costal cartilage
and not rib.
o Tenuous blood supply- limits manipulation and contouring of the
transferred bone
o inadequate for dental rehabilitation
o placement of the bone is limited by the arc of rotation of the muscle
o limited mobility of the soft-tissue component relative to the bone
o excessive bulk of the flap
o long-term bone resorption
o risk of pneumothorax.
Higher risk of complications in smokers and women (thicker adipose tissue
between the muscle and the skin)
overall complication rate was 58%. The partial flap loss rate was 36% and the
fistula rate was also 36%.
Latissimus dorsi
 Origins
1. spinous processes and supraspinous ligaments of T7-S5
2. fuses with lumbar fascia – inserting on medial 1/3rd of posterior iliac crest
3. 4 slips from lower 4 ribs interdigitating with external oblique
4. tip of scapular
 Insertion
1. floor of bicipital groove
 Action
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4. internal rotation
5. adduction
three angiosomes
1. the proximal portion of the muscle, which is supplied by the thoracodorsal
pedicle
2. the mid and medial portion, which is supplied by the posterior intercostals
3. the most caudal portion which is nourished by the lumbar vessels.
Thus caudal portion least reliable - vascularity diminishes when the “tertiary”
territory is harvested by crossing the second set of choke vessels.
skin islands placed over the upper two-thirds of the muscle consistently survive
whereas the distal flap apparently depends on proximal skin for its blood supply.
Sternocleidomastoid flap
 Ariyan states that the sternocleidomastoid musculocutaneous flap is “the most
tenuous of all the musculocutaneous flaps used for head and neck reconstruction.”
 50% have at least partial flap loss
 flap is most reliable when based on the occipital artery while retaining the
 skin bridge. This reliably supplies only the superior third of the muscle.
 main limitations of the flap are an arc of rotation that is determined by the course
of the spinal accessory nerve within the muscle, and risk of transecting the
occipital artery if an upper neck dissection is performed
 leaving the superior thyroid artery and vein intact increases its reliability but
reduces its arc
 Disadvantages:
1. loss of protection of great vessels
2. contraindicated ipsilateral flap in clinically positive neck
3. contour deformity
4. unreliable distal skin paddle
Platysmal flap
 2 basic designs
1. based medially – pivot on mandibular symphysis
2. based laterally – pivot on mandibular angle
 intact facial artery is not crucial for survival of the platysma musculocutaneous
flap.
 Blood supply
1. superior thyroidal artery - midportion
2. submental branch of the facial artery - anterosuperior
3. cutaneous branches to the sternocleidomastoid muscle of the occipital artery –
posterosuperior
4. transverse cervical artery- inferoposterior
5. branches of the supraclavicular artery -inferoanterior
 Venous drainage was to the external jugular and anterior medial jugular veins
 Previous chemotherapy, radiotherapy, or neck dissections are reported to cause
high rates (18% to 45%) of complications of platysma flaps. Total or partial
necrosis of the skin island or the flap, fistula, hematoma, and cellulitis are the
most common complications.
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flap should not be used for patients who had undergone neck dissection or surgical
procedures on the neck, those with positive lymph nodes or large defects, and
those who had recently undergone radiotherapy.
Sacrifice of the external jugular vein during neck dissection causes serious venous
drainage problems on the flap
Trapezius flap
 Type II
 Blood supply
1. occipital artery - upper part
2. superficial cervical artery (superficial
branch of the transverse cervical artery)
– middle and lateral part
3. dorsal scapular artery (deep branch of
the transverse cervical artery) and
segmental 3rd to 6th posterior intercostal
perforators – lower part
 Anatomy of transverse cervical and dorsal
scapular shows considerable variation
 transverse cervical artery typically arises
from thyrocervical trunk at 1st part of
subclavian artery but may arise
separately from the 2nd part
 transverse cervical may arise in the third
part where it gives off the superficial
cervical and dorsal scapular (deep branch) arteries
 dorsal scapular artery
o may arise separately from 3rd part of
subclavian or as deep branch of transverse
cervical artery
o runs deep to the levator scapulae and minor
rhomboid muscles.
o follows the medial border of the scapula
much more laterally than the superficial
cervical artery
o A branch penetrates between the minor
and major rhomboid muscles at the level
of the spine of the scapula and continues
under the surface of the trapezius muscle
close to the medial border of the scapula.
o At the level of the cranial border of the
major rhomboid muscle there was always a
descending branch running deep to this
muscle, which has to be divided for flap
elevation.
o In all cases the dorsal scapular nerve
accompanied the dorsal scapular artery
 superficial cervical artery (superficial branch of
the transverse cervical artery)
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o always runs superficial to the levator scapulae and rhomboid muscles,
reaching the trapezius muscle and dividing more medially into a short
ascending and a longer descending branch to the scapular spine.
o lies in the middle between the medial border of the scapula and the vertebral
column.
o The vessel was accompanied by branches of the accessory nerve.
One-third of the skin island must be over the trapezius muscle closer to the
vertebral spine to ensure musculocutaneous blood supply and should not be
extended more than 10 cm distal to the inferior angle of the scapula.
minor rhomboid muscle can be divided and flap tunneled under levator scapulae
to widen the arc of rotation if necessary.
Action
o Retract the scapula
o Rotate the scapula upwards
3 flaps may be raised
1. upper third – based on occipital artery
2. middle third – cervicohumeral flap, based on ascending branch of superficial
cervical artery
3. lower third – dorsal scapular artery
Potential problems in use of this flap stem from the variable origin of the
superficial branch of the artery and an even more undependable venous drainage.
In the event of a previous neck dissection, it is important to ensure that the
transverse cervical artery is intact before embarking on a reconstruction with this
flap.
Serratus Anterior Flap
 Type III muscle
 Action: protract the scapula
 based on a fasciocutaneous extension anteriorly and inferiorly from the 6th to the
8th slips
 long (15 - 20 cm) pedicle, skin paddle up to 10cm wide with direct closure
 vascularised rib may be used (Poole)
 lat dorsi can be harvested as a second flap on the same pedicle
Radial forearm flap
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Type C fasciocutaneous flap, ie, a flap supported by multiple small perforators
along its length, which reach it from a deep artery by passing along a fascial
septum between muscles.
The advantage of the radial forearm being a Type C flap is that it can be used as a
conduit for blood to a second flap.
When raised with bone, a small portion of the FPL muscle is required.
o Bevel bone cut, and remove only 1/3rd of radial diameter
o Harvested between insertion of brachioradialis and pronator teres
May be raised with brachioradialis for muscle bulk
Innervated flap using lateral cutaneous nerve of forearm
Raised with Palmaris longus for lip resuspension
Main criticism - problems with the donor site.
o When the skin island is designed distally over the wrist and a skin graft is
used to cover the donor site, the graft fails to take completely in
approximately 33% of patients, exposing the wrist tendons.
o To avoid this:
1. take skin island proximally
2. ulnar transposition flap to cover defect
3. turnover muscle flaps of the FPL and FDS to cover the FCR tendon.
4. using a skin-grafted fascial forearm flap with no skin from the donor
site
5. preserving the deep fascia overlying the muscles.
6. applying a full-thickness skin graft to the donor site
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