Chapter 65 - Skin Grafts, Local Flaps

Question 1

Advantage of orienting wound closure parallel to relaxed skin tension lines

Answer 1

camouflage scar
limit tension
optimal aesthetic

Question 2

advantage/dis of FTSG

Answer 2

limit contraction
improved texture and color match
DIS: reduced survival rate, longer heaing

Question 3

Ideal direction of tension vector

Answer 3

away from distortable structures i.e. lower lid

Question 4

How big arc of rotation should be

Answer 4

4x diameter of defect

Question 5

Layers of skin

Answer 5

Epidermis (keratinizing stratified squamous)
Basement membrane
papillary (thin) dermis
reticular dermis

Question 6

Reconstructive ladder

Answer 6

secondary intention/granuloma
primary close
STSG
FTSG
local flap
regional flap
free flap

Question 7

how to harvest FTSG

Answer 7

deep to dermis, within superficial subcutaneous plane

Question 8

Factors affecting skin graft viability

Answer 8

recipient/graft vascularity
contact between graft and recipient site
systemic illness
worse if irradiated tissue, exposed bone/cartilage, infected, bleeding

Question 9

Phases of skin graft survival

Answer 9

plasma imbibition- diffusion of nutrition from serum
inosculation- blood flow reestablished between graft and recipient capillaries betweem day 3-7
revascularization- by day 4, new vessels grow into graft

Question 10

ADV/DIS of STSG

Answer 10

increased viability (more capillary exposure on undersurface)…greater nutrient absorption
quicker revascularization
poor texture/color match

Question 11

How long to leave dressing in place after skin graft

Answer 11

5-7 days to enable graft adherence, prevent desiccation

xeroform/petroleum gauze bolsters

Question 12

How to manage donor site

Answer 12

FTSG- close primarily
STSG: occlusive dressing
Moist, clean

Question 13

4 mechanisms of graft failure

Answer 13

inadequate recipient vascularity
shearing forces separating graft/site
hematoma/seroma preventing contact
infection

Question 14

orientation of RSTL to underlying facial mimetic muscles

Answer 14

perpendicular

Question 15

undermining

Answer 15

skin and some SQ fat released from underlying fascia
lysis, release of vertical attachments between dermis, SQ tissue
Skin slides more freely, DEC tension

Question 16

How to use facial aesthetic units when planning flap

Answer 16

forehead, eyelids, cheeks, nose, lips, mentum, auricules
design flaps within same aesthetic region
orient incisions along borders of aesthetic units

Question 17

Random vs axial flap

Answer 17

Random- based on subdermal plexus, no named vessel

axial- dominant/named vessel

Question 18

Advancement vs pivotal flap

Answer 18

Adv: linear, advanced into defect, requires stretching, so best if significant laxity
Piv: pivoting tissue around fixed point…ie rotation/transposition/interpolated

Question 19

Transposition vs interpolated flap

Answer 19

T: rotate over segment of normal skin. i.e. rhombic, bilobed
I: base not contiguous with defect…pedicle crosses over intervening tissue. Second stage later to divide/inset pedicle. Ex is PMFF

Question 20

How does a Z-plasty change a scar?

Answer 20

interrupt linearity, lengthen, change orientation

Question 21

Increase in scar length with 45/60 z-plasty

Answer 21

45: 50%
60: 75%