Chapter 11.

Principle of Muscle & MC flap

CLASSIFICATION OF MUSCLE FLAPS

PREDICTION OF ARC OF ROTATION

PREDICTION OF SKIN TERRITORY

DESIGN OF DISTALLY BASED FLAPS

REFINEMENTS IN MUSCLE AND MUSCULOCUTANEOUS FLAPS

SELECTION OF SPECIFIC MUSCLE AND MUSCULOCUTANEOUS FLAPS

REGIONAL APPLICATION OF MUSCLE AND MUSCULOCUTANTOUS FLAPS

Head and Neck

Breast

Mediastinum

Chest Wall and Pulmonary Cavity

Abdomen

Groin and Perineum

Lower Extremity

Foot

Pressure Sores

MANAGEMENT OF THE PATIENT

COMPLICATIONS

□ flap surgery의 successful outcome을 결정하는 3 most important factors

① coverage : with reliable & durable tissue

② form : must strive to restore form at the recipient site & simulaneously avoid donor site defomity

③ function : in transposing of transplanting a muscle from one site to another must realize the effect on function

CLASSIFICATION OF MUSCLE FLAPS

1. Classification system of muscle by Mathes & Nahai

2. Muscle의 5 different vascular pattern

PREDICTION OF ARC OF ROTATION

1. arc of rotation의 결정요소, vascular pedicle 수와의 관계

2. □reverse arc of rotation"

PREDICTION OF SKIN TERRITORY

1. Cutaneous vascular system은 3가지 pattern을 가짐

① direct cutaneous vessels

② musculocutaneous perforator

③ fasciocutaneous vessels

2. the major blood supply to skin is subject to regional variation

① overlying the broad, flat muscle(eg. LD) - 주로 MC perforator에 의존

② overlying the thin, narrow muscle(eg. gracilis) - 주로 FC perfortor에 의존

3. 각 superficial muscle은 바로 위 skin에 blood supply 가능

: muscle border에서 3 ~ 4cm 까지 확장할 수 있음

4. skin island flap을 작도하기 좋은 muscle

① type V(also type III) muscle : 가장 유용

- skin island가 prox, dominant pedicle혹은 2o segmental pedicle 모두 가능.

② type I muscle : especially useful in that of the blood supply generally supports all the overlying skin

cf) type II, IV : flap elevation시 minor or segmental pedicle의 division이 필요하며, 이때 이들에 의해 supply받는 skin territory가 necrosis 될 수도 있다.

DESIGN OF DISTALLY BASED FLAPS

Distally based flaps : minor or segmental vessel based로 flap 거상이 가능

1. 그러나 lesser pedicle의 크기와 위치에 변동이 많다 → not entirely redliable

2. prior delay of muscle by selective division of the dominant pedicle

--> may improve the chance of flap survival

3. minor pedicle에 해당하는 m. 부위를 transposition하는 것이 안전.

REFINEMENTS IN MUSCLE AND MUSCULOCUTANEOUS FLAPS

1. technique in splitting the muscle to preserve tissue & function

① LD : for lining & skin coverage in esophageal reconstruction

② PM : for chest wall & neck reconstruction

2. preservation of function	: without completely disrrupting origin & insertion

--> ambulatory환자의 sacral sore제건시 sup. half of GM만 사용

3. technique of combination flaps : useful in extensive defect

① LD + scapular flap( MC + FC or MC + axial pattern )

② gluteal thigh flap : inf, gluteal MC flap + post. FC extension

□ advantage

ⓐ bulk와 length추가 가능

ⓑ defect에 맞춰 더 섬세한 재건이 가능

4. specialized tissue flap : restore sensation & motor function & bony str.

ADVANTAGES AND DISADVANTAGES OF

MUSCLE AND MUSCULOCUTANEOUS FLAPS

1. Advantage

① 확실한 pedicle과 풍부한 blood supply

② vascular pedicle이 surgical defect외부에 위치

③ deep extensive defect & exposed vital str.에 muscle bulk로 protection

④ muscle이 malleable → 원하는 모양, volume으로 manipulation

⑤ well-vascularized m. →  bacterial inosculation, infection에 저항

⑥ muscle or MC flap사용한 reconstruction → 보통 1 stage procedure로 가능

⑦ function(motor/sensory) restoration이 가능

⑧ 특정 defect의 choice method가 부적절할 때 좋은 alternative means

2. Disadvantages

① donor defect → loss some degree of function

② donor defect → esthetic unacceptable to patient

③ excessive bulk → esthetically unacceptable

④ m. or MC flap의 atrophy → adequate coverage의 fail

⑤ m. or MC flap loss → larger deformity

SELECTION OF SPECIFIC MUSCLE & MUSCULOCUTANEOUS FLAPS

□ 8 factors can assist the selecation of muscle

① muscle ideally should be adjacent to the defect

② defect를 cover하는데 적당한 size와 bulk

③ muscle should be expendable

④ vascular pedicle의 status를 술전 알아야

⑤ donor defect를 고려

⑥ cutaneous territory가 sufficient size와 acceptable texture

⑦ sensation, motor function이 필요할 경우 적절한 flap 선택(ex, TFL)

⑧ vascularized bone이 필요한 defect에는 osteomusculocutaneous flap

REGIONAL APPLICATION OF MUSCLE AND MUSCULOCUTANEOUS FLAPS

Head & Neck

□	Local	: temporalis, SCM, platysma

Distant : pectoralis major, trapezius, LD, microvascular transfer

1. the primary application of the muscle or MC flap in head & neck

① provision of tissue bulk for a significant defect

② protective coverage for vital structure

③ provision of skin for intraoral lining & coverage

④ provision of skin for skull, facial & neck defects

2. Temporalis m. (type III)

① fan-shaped, bipenniform m.

② Ix : turn-over flap for orbit, superior maxilla, ear

3. SCM(type II)

① least reliable flap : 20% failure rate, 30% Cx rate

② Ix : intraoral & pharyngeal reconstruction

③ carrier for vascularized clavicle → mandibular reconstruction

4. Platysma m.(type II)

① use as MC island flap,

② Ix : intraoral, lip, lower midface, ant. neck reconstruction

③ 장점: thinness, pliability, regionality, skin texture, color match, capability of providing sensation & animation

5. pectoralis major(type V)

① more valuable than deltopectoral flap

: for thin defect of middle & lower 3rd of face & neck

② most common application in the head & neck reconstruction

ⓐ external resurfacing of the skin of the face & neck

ⓑ intraoral & pharyngeal lining

ⓒ carrying vascularized rib & skin in mandibular reconstr.

ⓓ esophageal reconstruction

③ one of the most versatile flaps in head & neck reconstruction

④ mediastinal coverage

6. trapezius(type II)

① lower facial reconstr. esp, ear & parotid region

② lat. upper face & scalp repair

③ ant & post neck reconstr.

④ orbital reconstr. using an extended flap

⑤ pharyngo-esophageal reconstr.

⑥ mandibular reconstr. by the incorporated vascularized bone

- clavicle 특히 lateral aspect, scapular spine

7. latissimus dorsi m.(type V)

① originally as a superior based flap

② PM 만큼 versatile하지 못함

: but, hair-free skin, hidden donor site scar등이 장점

③ the most common uses in head & neck

ⓐ reconstr. defects of the post neck, shoulder, ant neck,

lower face, occipital scalp, intraoral & pharyng-esophagus

ⓑ in the restoration of facial function & contour

cf) split LD : skin coverage & intraoral lining

Breast

□	Local : pectoralis major, serratus ant, pectoralis minor

Distant : LD, rectus abdominis, microvascular transplantation

1. pectoralis major(V) : most common reconstr. technique for breast

: within an intact PM & adequate overlying skin

→ the submuscular placement of a prosthetic implant

□ submuscular placement의 장점

ⓐ softer,

ⓑ more natural contour

ⓒ lower risk of implant exposure & extrusion

ⓓ smaller incidence of capsular contracture

2. latissimus dorsi(V)

□ 단점 : 일반적으로 얇아 projection을 위해 prosthetic implant가 필요하다

3. Rectus abdominis(III)

① play a vital role

ⓐ flexing the vertebral column

ⓑ supporting the abdominal wall

ⓒ also assist defication, urination

② post. sheath

ⓐ arcuate line 위 : ant. rectus sheath만큼 강함

ⓑ arcuate line아래 : transversalis fascia만으로 구성

4. TRAM flap(transverse rectus abdominis myocutaneous flap)

① Indication for the TRAM flap in breast reconstruction

ⓐ 많은 양 lower abdominal tissue지닌 사람에서 skin, soft tissue필요시

ⓑ prosthetic implant없이 autologous tissue reconstr. 원하는 경우

ⓒ back scar 보다 abdominal scar가 더 낫다고 생각하는 경우

ⓓ 다른 방법으로 좋지 못하였던 경우

② TRAM flap의 relative contraindication

ⓐ thin patient(lower abdominal tissue가 적은)

ⓑ child bearing years 동안의 nullipara

ⓒ abdominal wall hernia histoy

ⓓ extremely obese patient

ⓔ heavy smoker

ⓕ chest wall에 irradiation을 받은 history(int. mammary a.의 경로 따라)

ⓖ lower abdominal scar를 가진 patient

③ TRAM flap의 장점

ⓐ provide sufficient bulk

ⓑ horizontal scar가 esthetically acceptable

ⓒ flap의 transposition이 single operation으로 가능

ⓓ skin의 quality가 LD보다 좋음

ⓔ abdominoplasty를 동시에

④ major disadvantage of TRAM flap : risk of abdominal hernia formation

⑤ Hernia방지를 위한 방법

ⓐ direct anatomic multilayered closure(most important)

ⓑ centralizing the remaining abdominal muscle

ⓒ linea alba, linea semilunaris 보존

ⓓ ant. sheath의 med. & lat. margin을 모두 보존 → ant. sheath repair

ⓔ 반대편 ant. sheath로 turn over flap

ⓕ muscle sparing technique사용

ⓖ relaxing incision으로 local tissue를 옮겨 closure

ⓗ autogenous graft: de-epithelized skin, upper ant. rectus fascia

□ prolene mesh

⑥ vertical rectus abdo.의 단점(LD에 비하여) : depressed, paramedian abdominal scar at donor site

5. microvascular composite tissue transplantation

① donor: groin, LD, TFL, GM

ⓑ the microvascular anastomosis of the inf. pedicle of the TRAM flap to the appropriate recipient vessels in the axilla when the circulation of the TRAM flap via the sup. pedicle is in question.

Mediastinum

Local : pectoralis major :	transposition(thoracodorsal a. pedicle)

turn over(int. mammary a.)

Distant

① rectus abdominis: inf. mediastinal

② LD

ⓐ indication : absent or damaged pectoralis major m. by previous incision or RT

ⓑ 장점 : pedicle & donor site are outside the infected area

ⓒ 단점 : back에서 얻어야 함.

thin --> extensive, deep defect에 부적절

③ Omentum

Chest Wall & Pulmonary Cavity

Local

① PM : lower neck과 upper 3rd of sternum의 defect에 choice

② LD

ⓐ preferred for wound of ant. chest wall that require removal of 2 ~ 3 ribs & resection of less than 8 cm of skin.

ⓑ other chest wall defect : Poland's syndrome, spina bifida defect diaphragmatic hernia

③ SA(III)

Distant : RA(III)

Abdomen

Local

① RA

ⓐ flap of choice for unilateral abdominal defect

ⓑ extended DIEA flap consists of an inf. based RA MC flap with a sup-lat. FC extension --> groin, thigh까지 cover가능

② ext. oblique : small full thickness upper abdominal wall defect

Distant

① LD : sup-lat. abdominal wall defect

② rectus femoris

③ TFL : one of choice for lower abdominal wall & groin defect

unique quality

ⓐ relatively generous amount of vascularized fascia & skin

ⓑ low donor site morbidity

Groin & Perineum

Local : sartorius(IV)

① limited arc of rotation

--> division of 1-2 of the most proximal pedicle

ⓑ 용도 : for coverage of exposed femoral vessel & prosthetic vascular graft

Distant

① gracilis(II)

ⓐ both ant. & post arc of rotation

ⓑ 용도

㉠ groin & perineal reconstr

㉡ vagina, penis, scrotum, anal sphincter

② TFL

ⓐ choice for coverage of the groin

ⓑ 용도 : vulva & recurrent inguinal hernia reconstr.

③ rectus femoris

④ RA

⑤ GM : for pelvic & perineal defect & rectal sphincter reconstr

□ gluteal thigh flap = inf. part of GM + post thigh skin(inf. gluteal a.)

→ 특히 deep perineal & pelvic defect의 재건에 유용

□ fascia보다 muscle로 cover하는 것이 좋은 경우

: exposed prosthetic vascular graft

→ sartorius, RF, RA, vastus lateralis

Lower Extremity

Local

① gastrocnemius(I):

ⓐ wide arc of rotation

□ 용도

㉠ coverge of knee

㉡ upper 1/3 of leg의 bone exposure(middle 1/3도 가능)

② soleus(II)

ⓐ choice of middle 1/3 of leg(lower 1/3 of leg에도 가능)

ⓑ Gc M이 compensation하므로 기능상 문제 없음

ⓒ prime ankle plantar flexor & stabilize ankle

→ muscle splitting해야

Distant

① microvascular transplantation: LD, gracilis, SA, RA...

② cross leg flap

Foot

Local

① FDB(II)

ⓐ island flap based on lat. plantar a.

→ cover malleolus & heel pad(post-sup)

ⓑ retrograde lat. plantar a. flap based on distal retrograde flow for med. & lat. metatarsal head defect

ⓒ calcaneal defect시에 choice

cf) lateral plantar a. division시 dorsalis pedis & post. tibial a. 의 patency를 확인해야한다.

: DPA or PTA가 막힌 환자는 lat. plantaris a가 collateral flow의 vital conduit

② abductor hallucis(II) : med. plantar a.

for defect just inf. to the med. malleolus

for defect of prox. med. aspect of foot dorsum

③ abductor digiti minimi(II) : lat. plantar a.의 br.

for defect adjacent to the lat. malleolus

□ the procedure of choice for extensive foot defect

① microvascular transplantation

② from ; gracilis, SA, LD

Pressure Sore

Local

① GM(III)

ⓐ deep sacral & ischial pressure sore의 choice

ⓑ ambulatory pt: function preserved technique

→ bilat. advancement flap(sup half of GM)

ⓒ sliding flap : small sacral defect

transposition flap : larger defect

gluteal thigh flap : extensive pressure sore

Distant

①TFL(I)

ⓐ flap of choice for constructing trochanteric sores

a reliable alternative flap for ischial defect

ⓑ 장점

㉠ donor morbidity ↓

㉡ vascularized durable fascia

㉢ sensibility(lat. femoral cutaneous n; L2-L3)

ⓒ 단점 : relatively thinness → 해결 : sandwich modified flap

② gracilis(II) : ischial defect

③ hamstring

ⓐ 구성

㉠ biceps femoris	㉡ semimembranous

㉢ semitendinosus

ⓑ post. thigh의 muscle group

common origin : ischial tuberosity

ⓒ ischial pressure sore에 유용

MANAGEMENT OF THE PATIENT

* management of the patient

COMPLICATIONS

□ complication : 3 factors of error

① judgement

ⓐ inadequate preparation

ⓑ inadequate flap design

ⓒ inadequate knowledge of anatomy

② surgical technique

③ patient management

□ 환자 management의 common error

ⓐ underlying medical problem 무시

ⓑ intravascular valve 상태 파악 부족

ⓒ flap viability, perfusion 파악 부족

□* surgical complication, 특히 spasm, kinking, shearing, twisting방지를 위한 방법

① muscle과 fascia를 skin에 temporary suture --> vessel shearing방지

② 필수적이 아니면 vessel의 skeletonization은 피할 것

→ spasm과 injury를 피하기 위해

③ skin bridge 아래의 tunnel을 통한 flap에서 constrictive skin bridge에의한 tourniquet effect 피할 것